Nico Dauphine on Trial (Day 3)

27 Oct 2011•In the News, Legal Issues

Testimony wrapped up Wednesday afternoon in Nico Dauphine’s attempted animal cruelty trial. Among the witnesses for the Defense: Peter Marra, Dauphine’s advisor at the Smithsonian’s Migratory Bird Center—who’s previously described TNR as “essentially cat hoarding without walls.” [1] Dauphine took the stand as well, and, as I understand it, did herself no favors career-wise (even in the event she’s found not guilty).

Wednesday evening, Fox 5 News released the surveillance video at the heart of the Washington Humane Society’s investigation. In it, Dauphine is seen attending to some mysterious task—picking up the cat food that was left out by a neighbor, according to the Defense; adding rat poison to it, according to the Prosecution—before entering the building.

A decision is expected Monday afternoon.

Literature Cited
1. Lepczyk, C.A., et al., “What Conservation Biologists Can Do to Counter Trap-Neuter-Return: Response to Longcore et al.” Conservation Biology. 2010. 24(2): p. 627–629. www.abcbirds.org/abcprograms/policy/cats/pdf/Lepczyk-2010-Conservation%2520Biology.pdf

National Feral Cat Day 2011

12 Oct 2011•In the News

As many of you are no doubt aware, Sunday is National Feral Cat Day, a holiday created 10 years ago by Alley Cat Allies “to raise awareness about feral cats, promote Trap-Neuter-Return, and recognize the millions of compassionate Americans who care for them.” This year, there are more than 320 events planned across all 50 states.

Even so, I’ll bet there are a number of scientists, journalists, and others who—despite devoting a great deal of attention to the topic the rest of the year—have allowed the holiday to sneak up on them, and therefore haven’t made plans. Here, then, are some suggestions for how some of these folks (listed in no particular order) might mark the 10th annual National Feral Cat Day.

Christopher Lepczyk, Assistant Professor in the University of Hawaii’s Department of Natural Resources and Environmental Management, who, along with Tom Will (see below) will be organizing the Informing Local Scale Feral Cat Trap-Neuter-Release Decisions workshop at The Wildlife Society’s annual conference in November: Revisit your PhD work and see if you can actually get the predation “estimates” to add up. (Too late to address the flawed methods involved.)
Tom Will, USFWS biologist: Launch a detailed survey to account for the 150 million cats you claim are (1) roaming the U.S., and (2) responsible for declining songbird populations.
Michael Hutchins, TWS Executive Director/CEO: Fact-check your feral cat/TNR “fact sheets.”
Steve Holmer, senior policy analyst, American Bird Conservancy: visit the CDC website, where you can review actual rabies exposure data.
Anne Morkill, Wildlife Refuge Manager, Florida Keys National Wildlife Refuges Complex: Resign.
Timothy O’Hara, reporter for the Key West Citizen: Apply for a job in the USFWS PR office (no need to change what you write, of course).
Nico Dauphine, who is scheduled to appear in court on the 24th of this month: Meet with a career counselor to discuss potential second acts.
Peter Marra, research scientist with the Smithsonian’s Migratory Bird Center (and Dauphine’s adviser): Return any public funding used to support the Center’s domestic cat research.
Frank Gill, author of Ornithology and former chief scientist for the National Audubon Society: Issue a formal retraction of the sections describing predation by cats in both the second and third editions of Ornithology.
Christine Stracey, author of “Resolving the urban nest predator paradox: The role of alternative foods for nest predators”: Redistribute your nest cameras to locations where there are predators other than cats.
Nohra Mateus-Pinilla, wildlife veterinary epidemiologist at the University of Illinois Prairie Research Institute: Apologize to graduate student Shannon Fredebaugh, whose extensive fieldwork was rendered largely useless because of an insufficient literature review and flawed analysis techniques (mistakes that should be prevented/corrected by her committee chair).
Kiera Butler, articles editor, Mother Jones magazine: Visit the San Francisco SPCA, where you might actually learn something about TNR.
SF Weekly reporter Matt Smith: Coordinate SF SPCA visit with Kiera Butler. You two ought to have plenty to talk about.
New York Times science writer Elisabeth Rosenthal: Update your contact list, removing Peter Marra and anybody from the American Bird Conservancy as reliable sources.

• • •

Thank you to all those who—whether one day a year or year-round—raise awareness about, and care for, abandoned, stray, and feral cats, and promote TNR.

Jake and Lily

19 Sep 2011•In the News, Legal Issues

Letter from young child who loved Jake the cat

Over the past few months, I’ve heard from several people familiar with Nico Dauphine’s cat-trapping activities in and around Athens, GA, during her days as a PhD student at the Warnell School of Forestry and Natural Resources. Three years ago, in Athens-Clarke County Magistrate Court, Dauphine referred to her roundups as “community service.”:

“Oh, I do it basically as a community service, because I volunteered at Athens-Clarke County Animal Control for many years, and they’ve told me that one of their big problems that there’s no public service to pick up cats, but a lot of people have concerns about stray cats around.”

I recently heard from a former neighbor of Dauphine’s, whose family, like the defendant in the 2008 court case, was a victim of her “community service.” He agreed to share with me a letter he wrote—along with one written by one of his children (pictured above)—describing their experience:

“For more than six years my family has been consistently harassed by our neighbor Nico Dauphine… My wife and our children are fond of our pet cat. We have never owned more than two at a time, however we have been twice charged with a violation of the Athens leash law for our cat wandering into Nico’s yard. It was peculiar that when I requested to be shown the legal violation, that Patrick [Rives], Nico’s boyfriend, and head of animal control, handed a copy of the dog leash law with the word “dog” crossed out and “cat” hand-written in. This indicates to me that there is no specific violation concerning wandering licensed pet cats. Regardless, this household was fined twice, $80 on one occasion in 2008 or 09… and once for $50 in 2010… Additional circumstances involved in these cases would in most circumstances be considered legal entrapment, as Nico baited traps in her backyard with very aromatic bait to attract cats, then would take the cats away and drop them where they would be killed in traffic, as the local shelter would no longer accept cats.

On no occasion did Nico ever inform me that she had caught my cat. As a good neighbor I, on several occasions, asked Nico to alert us when our pet had wandered into her yard. I even suggested that she spray them with a garden hose to encourage them to stay away from her yard. Our children, who were six and eight years old at the time, had to give up their pet, which they had cared for since it was a very small kitten, as he (Jake) would get out and hide in the overgrown brush lot that is Nico’s yard. The children were heartbroken and have as a result learned to hate Nico, which is a behavior we try to minimize in our children.

My pet Siamese, who I had owned for more than six years, was a trained companion animal, as I am totally blind. My cat Lily was trained to pick up dropped items for me, warn me of obstacles in my path in the house, and alert me to people at the door. Nico trapped Lily once in a trap, without any water, on a weekend when Nico had been away in Florida for at least three days. I rescued Lily on that occasion, and threw the trap cage back across the fence into Nico’s yard. In the spring of 2010, Lily got out of my house. As she is chipped, I began calling all the shelters after she was missing for a full day. It was later reported back to me that Nico had told some neighbors that she had gotten rid of that cat. The distress and emotional drain of that incident continue to be costly to me. I had to withdraw from my PhD program as a result, where I was at the point of beginning data collection.

An additional factor about maintaining total control of our pet cat, which is nowhere in the U.S. required, as far as my research has revealed, is that… my wife has [cerebral palsy] and cannot walk adequately to chase down an active animal once it has escaped the house. The cruelty to these pets and to the owners—frequently young children—as a result, is beyond levels that decent society will normally tolerate.”

Isn’t this the same Nico Dauphine whose attorney, following her arrest in May, told the press that Dauphine’s “whole life is devoted to the care and welfare of animals”? The same Nico Dauphine who landed a prestigious position with the Smithsonian Migratory Bird Center (part of the National Zoo), working alongside Peter Marra, conducting research “on [citizen participants’] free-roaming pet domestic cats”? And the same Nico Dauphine who was invited earlier this year by The Wildlife Professional to contribute to a special section of their Spring issue, “The Impacts of Free-roaming Cats” (in which Dauphine gives readers the ultimatum: “Pick One: Outdoor Cats or Conservation”)?

Of course. It’s also the same Nico Daupine who’s scheduled to appear in court October 24th, charged with attempted animal cruelty related to the poisoning of cats in her Washington, DC neighborhood.

Note: Patrick Rives did not respond to my e-mail request for comments about this story.

MoJo Losing Its Mojo

1 Jul 2011•In the News, The Cat Debate

Mother Jones, according to its Website, “is a nonprofit news organization that specializes in investigative, political, and social justice reporting.”

“…smart, fearless journalism” keeps people informed—“informed” being pretty much indispensable to a democracy that actually works. Because we’ve been ahead of the curve time and again. Because this is journalism not funded by or beholden to corporations. Because we bust bullshit and get results. Because we’re expanding our investigative coverage while the rest of the media are contracting. Because you can count on us to take no prisoners, cleave to no dogma, and tell it like it is. Plus we’re pretty damn fun.

Right up my alley. Until now.

With “Faster, Pussycat! Kill! Kill!,” published in the July/August issue, articles editor Kiera Butler fails rather magnificently all the way around.

(The article isn’t available directly from MotherJones.com yet, but you can read it (print it, too) simply by signing up for the magazine’s e-mail updates. Enter your e-mail address and click “Sign Up.” In the next window, click on “ACCESS THE ISSUE NOW”—the full issue will then open automatically in Zinio, a digital magazine reader. “Faster, Pussycat! Kill! Kill!” begins on p. 72.)

Cover Art: "Faster, Pussycat! Kill! Kill!"

The title, by the way, comes from a 1965 cult classic in which “Three strippers seeking thrills encounter a young couple in the desert.” Sadly, the film is a better reflection of reality than the information in Butler’s article is.

Population of Cats
The most obvious blunder: Citing what seems to be the same data set (“the US feline population has tripled over the last four decades”) I referred to in my “Spoiler Alert” post, Butler arrives not at 90 million or so, as indicated in the original source [1], or even the bogus 150 million figure the U.S. Fish and Wildlife Service’s Tom Will tried to sell last year to the Bird Conservation Alliance.

No—according to Butler, there were 600 million cats in this country in 2007.

At that time, the human population was 301.3 million. For the sake of easy math, then, let’s call it two cats for every human (talk about “hip-deep in cats”!). This, I believe, sets a new record for absurd population claims—far surpassing the previous record held by Steve Holmer, senior policy advisor for the American Bird Conservancy.

And from here, it only gets worse. While her grossly inflated population figure might be attributed a simple mistake. These things happen (though, of course, one expects such things to be caught by somebody on the editorial staff). However, the misinformation, misrepresentations, and missteps that make up the bulk of “Faster, Pussycat!” betray either willful ignorance or glaring bias. Or both.

Smart, fearless journalism it is not.

One Billion Birds
Butler’s litany of complaints against feral cats is all too familiar: wildlife impacts (birds, in particular), public health threats, the “failures” of TNR, the powerful feral cat lobby, and the emotional/irrational nature of feral cat advocates (i.e., the classic “crazy cat lady” label). Her sources, too, include all the usual suspects; though few are cited, many others are obvious.

Sources of Mortality
Butler claims that domestic cats (“officially considered an invasive species”) top the list of mortality sources, killing perhaps one billion birds annually in the U.S. (Her tabulated comparison of seven mortality sources bears the familiar title “Apocalypse Meow.”)

The source of Butler’s “highest reliable estimates” is the U.S. Fish and Wildlife Service, though the one-billion-birds claim has been made by others, including Nico Dauphine and Robert Cooper, [2, 3] and Rich Stallcup. [4] (In fact, Dauphine refers specifically to Stallcup’s wild-ass guess back-of-the-envelope calculation in her infamous “Apocalypse Meow” presentation.)

Yet even ABC, never one to go easy on cats—or to let science get in the way of their message—ranks building collisions ahead of cats. (Interestingly, neither USFWS nor ABC mentions the most direct human-caused source of bird mortality—hunting—which may account for 120 million avian deaths annually in the U.S. [5])

The one-billion-birds claim hinges upon an inflated estimate of outdoor cats (Dauphine and Cooper, for example, ignore published survey results [6–8], in effect doubling the number of pet cats allowed outdoors) and inflated predation rates (typically extrapolated from small, flawed studies). Multiplying one by the other, the result is impressive (hence, it’s “stickiness”).

Unfortunately, it’s also meaningless.

Still, such aggregate figures are useful for providing a scientific veneer to what is, at its core, little more than a witch-hunt. All of which makes it an easier sell to the media and the general public.

But sound bites ignore the importance of context. Aggregate predation rates, for example, fail to differentiate across vastly different habitats (e.g., islands, forests, coastlines, etc.), species (e.g., songbirds, seabirds, etc.), conditions (e.g., sick and healthy, young and old, etc.), and levels of vulnerability (e.g., ground-nesting and cavity-nesting species, rare and common species, etc.).

Predators—cats included—catch what’s easy. Indeed, at least two studies [9, 10] have found that cat-killed birds tend to be less healthy than those killed in non-predatory events (e.g., the other six mortality sources shown in Butler’s table).

Island Extinctions
In asserting that cats are “responsible for at least 33 avian extinctions worldwide,” Butler overlooks or ignores a critical detail: those extinctions involve primarily—perhaps exclusively—island species, with “insular endemic landbirds [being] most frequently driven to extinction” [11] And even this point is a matter of some debate. “Birds (both landbirds and seabirds) have been affected most by the introduction of cats to islands,” writes Mike Fitzgerald, one of the world’s foremost experts on the subject, “but the impact is rarely well documented.” [12]

“In many cases the bird populations were not well described before the cats were established and the possible role of other factors in changes in the bird populations are treated inadequately.” [12]

So what’s the impact of cats on continents?

In 2000, Fitzgerald and co-author Dennis Turner published a review of 61 predation studies, concluding unambiguously: “there are few, if any studies apart from island ones that actually demonstrate that cats have reduced bird populations.” [13]

Catbird Mortalities
Referring to research conducted by the Smithsonian Migratory Bird Center’s Peter Marra, Butler contends that “cats caused 79 percent of deaths of juvenile catbirds in the suburbs of Washington, DC.” In fact, Marra and his colleagues documented just six deaths attributable to cats, of 42 overall (then justified another three on dubious grounds). [14]

That 79 percent figure comes from dividing the number of deaths attributed to all sources of predation (33) by the total number of deaths documented over the course of the study (42). Butler’s misreading overstates predation by cats by more than 500 percent.

Public Health Threats
“Feral cats,” writes Butler, “can carry some heinous people diseases, including rabies, hookworm, and toxoplasmosis, and infection known to cause miscarriages and birth defects.” Her omission of infection rates—remarkably low in light of the frequent contact between humans and cats—suggests an interest more in fear-mongering than anything else.

Hookworms
A hookworm outbreak in the Miami Beach area in late 2010 made headlines, prompting officials to create a “cat poop map” (cats can pass hookworm eggs in their feces).

Meanwhile, Floridians were dying of influenza or pneumonia by the hundreds. In fact, according to the Florida Department of Health, 100–140 or so die each week during the winter months. (Actually, that figure accounts for only 24 of the state’s 67 counties, so the total is likely much higher.)

My point is not to dismiss the risk of “heinous people diseases” (or the suffering of those who become infected) but to put that risk into perspective. (In terms of public health, we’re better off focusing on frequent hand washing, sneezing into our sleeves, and, in the case of hookworms on the beach, wearing flip-flops—as opposed to, say, exterminating this country’s most popular companion animal by the millions.)

Toxoplasmosis
According to the Centers for Disease Control and Prevention’s Website, “Although cats can carry diseases and pass them to people, you are not likely to get sick from touching or owning a cat.” And, notes the CDC, “People are probably more likely to get toxoplasmosis from gardening or eating raw meat than from having a pet cat.”

(The same is true of feeding feral cats, by the way. While it’s true that their infection rates tend to be higher, [15] our frequent, close contact with pet cats more than offsets these differences.)

TNR
“In theory,” writes Butler, “TNR sounds great. If cats can’t reproduce, their population will decline gradually. Unfortunately, it doesn’t work. To put a dent in the total number of cats, at least 71 percent of them must be fixed, and they are notoriously hard to catch.”

In Los Angeles, adds Butler, “it failed miserably in the past.”

Contrary to Butler’s claims, however, there are numerous well-documented examples of TNR programs reducing colony size.

Perhaps the best-known TNR success story in this country is ORCAT. As of 2004, ORCAT, run by the Ocean Reef Community Association, had reduced its “overall population from approximately 2,000 cats to 500 cats.” [16] According to the ORCAT Website, the population today is approximately 350, of which only about 250 are free-roaming.

Other examples include a TNR program on the campus of the University of Florida University of Central Florida,
Orlando, in which caretakers found homes for more than 47 percent of the campus’ socialized cats and kittens, helping them reduce the campus cat population more than 66 percent, from 68 to 23. [17]

In North Carolina, researchers observed a 36 percent average decrease among six sterilized colonies in the first two years (even in the absence of adoptions), while three unsterilized colonies experienced an average 47 percent increase. [18] Four- and seven-year follow-up censuses revealed further reductions among sterilized colonies. [19]

A survey of caretakers in Rome revealed a 22 percent decrease overall in the number of cats through TNR, despite a 21 percent rate of “cat immigration.” [20]

And in South Africa, researchers recommended that “a suitable and ongoing sterilization programme, which is run in conjunction with a feral cat feeding programme, needs to be implemented” [21] on the campus of the University of KwaZulu-Natal’s Howard College—despite its proximity to “conservation-sensitive natural bush habitat and a nature reserve on the northern border.” [22]

The Cost of TNR
“Cash-strapped cities,” argues Butler, “can’t afford to chase down, trap, and sterilize every stray—a process that costs $100 per kitty.” So, can these cities afford to round up and kill the cats?

Mark Kumpf, past president of the National Animal Control Association doesn’t think so. “There’s no department that I’m aware of,” says Kumpf, “that has enough money in their budget to simply practice the old capture-and-euthanize policy; nature just keeps having more kittens.” Traditional control methods, he says, are akin to “bailing the ocean with a thimble.” [23]

The Cat Lobby
If TNR is so ineffective, why is it becoming the feral cat management approach of choice across the country (adopted in “at least 10 major cities,” according to Butler)? It must be the powerful cat lobby.

Alley Cat Allies, “whose budget was $5.3 million last year,” writes Butler, “has enjoyed generous grants from cat-food venders like PetSmart and Petco.”

It’s a play straight out of Dauphine’s playbook: paint the avian-industrial complex TNR opponents as victims of the powerful cat lobby. (In The Wildlife Professional’s recent special issue, “The Impact of Free Ranging Cats,” Dauphine complains: “The promotion of TNR is big business, with such large amounts of money in play that conservation scientists opposing TNR can’t begin to compete.” [24])

Alley Cat Allies
How generous were these grants, exactly? According to ACA’s 2010 Annual Report (PDF):

“Alley Cat Allies received more than $5.2 million in support between August 1, 2009 and July 31, 2010: more than 69,000 individuals contributed $4.8 million, including over $1 million in bequests. An additional $245,000 came from Workplace Campaigns, and over $14,000 came from foundation grants.”

Roughly 0.2 percent of their “total public support” came from all foundations combined. In 2009, grants and foundations accounted for 1.7 percent; in 2008, 1.0 percent. (Maybe Butler never got the memo re: MoJo’s commitment to bullshit-busting.)

New Jersey Audubon
Another of Dauphine’s complaints that found its way into “Faster, Pussycat!”:

“Pro-feral groups—there are 250 or so in the United States—have used their financial might to woo wildlife groups. Audubon’s New Jersey chapter backed off on its opposition to TNR in 2005, around the same time major foundations gave the chapter grants to partner with pro-TNR groups.”

What Butler (like Dauphine before her) fails to acknowledge is the important role NJAS plays in the New Jersey Feral Cat & Wildlife Coalition, which has developed a set of model protocols and ordinances designed to help municipal TNR programs in ensuring the protection of any vulnerable native wildlife (DOC).

This is exactly the kind of collaborative effort that should be supported.

For what it’s worth: it’s not clear that NJAS was easily wooed with grant funding. A quick visit to Guidestar.com reveals that NJAS brought in $6.8 million in 2008, and had $25.6 million in “net assets or fund balances” on its books. (I’ve been unable to determine the amount of grant funding NJAS received for “this important initiative,” as CEO and VP of Conservation and Stewardship Eric Stiles described it in a 2008 newsletter. [25])

Mental Health
Butler frames the TNR debate using what’s come to be standard form: rationale scientists on one side; on the other, cat advocates fueled by emotion. And mental illness, too, apparently: “There’s also speculation that [toxoplasmosis] can trigger schizophrenia and even the desire to be around cats—some researchers blame the crazy-cat-lady phenomenon on toxo.”

A Heated Debate
It’s a dangerous combination, according to Butler.

“Many of the biologists I spoke with say they’ve been harassed and even physically threatened when they’ve presented research about the effect cats have on wildlife.”

Is it really so one-sided?

Why didn’t Butler mention the case of Jim Stevenson, the Galveston birder who, in 2006, shot and killed (though not immediately) a feral cat within earshot of the cat’s caretaker? [26]

Or, more recently, the charges of attempted animal cruelty filed by the Washington Humane Society against Dauphine? (Or, for that matter, the stream of toxic comments almost guaranteed to accompany nearly any online story about feral cats or TNR.)

Clearly, the “cat people” don’t have a monopoly on emotional—even violent—responses to the issue.

Sustaining a Killer
When Butler tells an ecologist she knows that she’s feeding a feral cat, she’s told: “Basically, you’re sustaining a killer.” Which is essentially Butler’s intended take-away:

“Until they do [invent a single-dose sterilization drug], biologists recommend a combination of strategies. For starters, quit feeding ferals: Beyond sustaining strays, the practice often leads to delinquent pet owners to abandon their cats outdoors, assuming they will be well cared for.”

Are we to believe that abandonment is reduced or eliminated where the feeding of feral cats is prohibited? Owners (delinquent, I agree) interested in dumping their cats can, unfortunately, do so easily.

The far greater incentive for dumping comes from local shelters, most of which euthanize kill the majority of cats brought in. Many require a surrender fee.

I’m just about the last person to defend the dumping of cats, but shouldn’t we acknowledge the aspects of “animal control” policy that contribute to it?

But back to this idea that “no food” means “no ferals.” It sounds reasonable enough, but doesn’t hold up very well to scrutiny. For one thing, where there are humans, there’s food to be found. In fact, even where there are no people, cats don’t starve.

On Marion Island—barren and uninhabited—it took 19 years to eradicate approximately 2,200 cats. Their only human provision: “the carcasses of 12,000 day-old chickens” each injected with the poison sodium monofluoroacetate. [27] (The rest—the vast majority—were killed through the introduction of feline distemper, intensive hunting and trapping, and dogs. [28, 27])

Is Butler suggesting that the cats in her neighborhood would have it tougher than the Marion Island cats? Even setting aside the cruelty involved, we’re not likely to starve our way out of the “feral cat problem.” Unlike TNR, such an approach only drives the cats (and their caretakers) underground.

This, of course, is roughly the same approach that’s proved ineffective failed so spectacularly at addressing so many other complex issues, including drug enforcement, immigration policy, gays in the military, and so forth.

• • •

Since I launched Vox Felina last year, I’ve been critical of articles appearing in any number of publications: scientific journals (e.g., Conservation Biology), major newspapers (e.g., The Washington Post and The New York Times), an alt-weekly, and more.

None of which bothered me in the least, as I feel no particular connection to any of them. This is not to say that I don’t value, admire, and respect much of the work found, for instance, in the Times—only that I’ve no affinity for, or loyalty to, the paper itself.

But Mother Jones is different. Maybe it’s that whole bullshit-busting, take-no-prisoners, tell-it-like-it-is business—I’d like to think that’s something we share in common.

This time around, though, the magazine served up bullshit by the shovelful, swallowed in one gulp the misinformation churned out by ABC, The Wildlife Society, and other TNR opponents, and… well, told it like it isn’t.

With the publication of “Faster, Pussycat!,” Mother Jones failed miserably in its promise to readers. Which, I have to think, isn’t a lot of fun.

2. Dauphine, N. and Cooper, R.J., Impacts of Free-ranging Domestic Cats (Felis catus) on birds in the United States: A review of recent research with conservation and management recommendations, in Fourth International Partners in Flight Conference: Tundra to Tropics. 2009. p. 205–219. http://www.pwrc.usgs.gov/pif/pubs/McAllenProc/articles/PIF09_Anthropogenic%20Impacts/Dauphine_1_PIF09.pdf

3. Dauphine, N. and Cooper, R.J., “Pick One: Outdoor Cats or Conservation.” The Wildlife Professional. 2011. 5(1): p. 50–56.

4. Stallcup, R., “A reversible catastrophe.” Observer 91. 1991(Spring/Summer): p. 8–9. http://www.prbo.org/cms/print.php?mid=530

http://www.prbo.org/cms/docs/observer/focus/focus29cats1991.pdf

5. Klem, D., “Glass: A Deadly Conservation Issue for Birds.” Bird Observer. 2006. 2. p. 73–81. http://www.massbird.org/BirdObserver/index.htm

6. Clancy, E.A., Moore, A.S., and Bertone, E.R., “Evaluation of cat and owner characteristics and their relationships to outdoor access of owned cats.” Journal of the American Veterinary Medical Association. 2003. 222(11): p. 1541-1545. http://avmajournals.avma.org/doi/abs/10.2460/javma.2003.222.1541

7. Lord, L.K., “Attitudes toward and perceptions of free-roaming cats among individuals living in Ohio.” Journal of the American Veterinary Medical Association. 2008. 232(8): p. 1159-1167. http://www.avma.org/avmacollections/feral_cats/javma_232_8_1159.pdf

8. APPA, 2009–2010 APPA National Pet Owners Survey. 2009, American Pet Products Association: Greenwich, CT. http://www.americanpetproducts.org/pubs_survey.asp

9. Møller, A.P. and Erritzøe, J., “Predation against birds with low immunocompetence.” Oecologia. 2000. 122(4): p. 500–504. http://www.springerlink.com/content/ghnny9mcv016ljd8/

10. Baker, P.J., et al., “Cats about town: Is predation by free-ranging pet cats Felis catus likely to affect urban bird populations?“ Ibis. 2008. 150: p. 86–99. http://www.ingentaconnect.com/content/bsc/ibi/2008/00000150/A00101s1/art00008

11. Nogales, M., et al., “A Review of Feral Cat Eradication on Islands.” Conservation Biology. 2004. 18(2): p. 310–319. http://onlinelibrary.wiley.com/doi/10.1111/j.1523-1739.2004.00442.x/abstract

12. Fitzgerald, B.M., Diet of domestic cats and their impact on prey populations, in The Domestic cat: The biology of its behaviour, D.C. Turner and P.P.G. Bateson, Editors. 1988, Cambridge University Press: Cambridge; New York. p. 123–147.

13. Fitzgerald, B.M. and Turner, D.C., Hunting Behaviour of domestic cats and their impact on prey populations, in The Domestic Cat: The biology of its behaviour, D.C. Turner and P.P.G. Bateson, Editors. 2000, Cambridge University Press: Cambridge, U.K.; New York. p. 151–175.

14. Balogh, A., Ryder, T., and Marra, P., “Population demography of Gray Catbirds in the suburban matrix: sources, sinks and domestic cats.” Journal of Ornithology. 2011: p. 1-10. http://dx.doi.org/10.1007/s10336-011-0648-7

http://nationalzoo.si.edu/scbi/migratorybirds/science_article/pdfs/55.pdf

15. Dubey, J.P. and Jones, J.L., “Toxoplasma gondii infection in humans and animals in the United States.” International Journal for Parasitology. 2008. 38(11): p. 1257–1278. http://www.sciencedirect.com/science/article/B6T7F-4S85DPK-1/2/2a1f9e590e7c7ec35d1072e06b2fa99d

16. Levy, J.K. and Crawford, P.C., “Humane strategies for controlling feral cat populations.” Journal of the American Veterinary Medical Association. 2004. 225(9): p. 1354–1360. http://www.avma.org/avmacollections/feral_cats/default.asp

http://www.avma.org/avmacollections/feral_cats/javma_225_9_1354.pdf

17. Levy, J.K., Gale, D.W., and Gale, L.A., “Evaluation of the effect of a long-term trap-neuter-return and adoption program on a free-roaming cat population.” Journal of the American Veterinary Medical Association. 2003. 222(1): p. 42-46. http://avmajournals.avma.org/doi/abs/10.2460/javma.2003.222.42

18. Stoskopf, M.K. and Nutter, F.B., “Analyzing approaches to feral cat management—one size does not fit all.” Journal of the American Veterinary Medical Association. 2004. 225(9): p. 1361–1364. http://www.ncbi.nlm.nih.gov/pubmed/15552309

www.avma.org/avmacollections/feral_cats/javma_225_9_1361.pdf

19. Nutter, F.B., Evaluation of a Trap-Neuter-Return Management Program for Feral Cat Colonies: Population Dynamics, Home Ranges, and Potentially Zoonotic Diseases, in Comparative Biomedical Department. 2005, North Carolina State University: Raleigh, NC. p. 224. http://www.carnivoreconservation.org/files/thesis/nutter_2005_phd.pdf

20. Natoli, E., et al., “Management of feral domestic cats in the urban environment of Rome (Italy).” Preventive Veterinary Medicine. 2006. 77(3-4): p. 180–185. http://www.sciencedirect.com/science/article/B6TBK-4M33VSW-1/2/0abfc80f245ab50e602f93060f88e6f9

www.kiccc.org.au/pics/FeralCatsRome2006.pdf

21. Tennent, J., Downs, C.T., and Bodasing, M., “Management Recommendations for Feral Cat (Felis catus) Populations Within an Urban Conservancy in KwaZulu-Natal, South Africa.” South African Journal of Wildlife Research. 2009. 39(2): p. 137–142. http://dx.doi.org/10.3957/056.039.0211

22. Tennent, J. and Downs, C.T., “Abundance and home ranges of feral cats in an urban conservancy where there is supplemental feeding: A case study from South Africa.” African Zoology. 2008. 2: p. 218–229. http://login.ezproxy1.lib.asu.edu/login?url=http://search.ebscohost.com/login.aspx?direct=true&db=eih&AN=47391224&site=ehost-live

23. Hettinger, J., “Taking a Broader View of Cats in the Community.” Animal Sheltering. 2008. September/October. p. 8–9. http://www.animalsheltering.org/resource_library/magazine_articles/sep_oct_2008/taking_a_broader_view_of_cats.html

http://www.animalsheltering.org/resource_library/magazine_articles/sep_oct_2008/broader_view_of_cats.pdf

24. Dauphine, N., “Follow the Money: The Economics of TNR Advocacy.” The Wildlife Professional. 2011. 5(1): p. 54.

25. Stiles, E., NJAS Works with Coalition to Reduce Bird Mortality from Outdoor Cats. 2008, New Jersey Audubon Society. http://www.njaudubon.org/Portals/10/Conservation/PDF/ConsReportSpring08.pdf

26. Barcott, B. (2007, December 2, 2007). Kill the Cat That Kills the Bird? New York Times, from http://www.nytimes.com/2007/12/02/magazine/02cats-v–birds-t.html

27. Bester, M.N., et al., “A review of the successful eradication of feral cats from sub-Antarctic Marion Island, Southern Indian Ocean.” South African Journal of Wildlife Research. 2002. 32(1): p. 65–73.

http://www.ceru.up.ac.za/downloads/A_review_successful_eradication_feralcats.pdf

28. Bloomer, J.P. and Bester, M.N., “Control of feral cats on sub-Antarctic Marion Island, Indian Ocean.” Biological Conservation. 1992. 60(3): p. 211-219. http://www.sciencedirect.com/science/article/B6V5X-48XKBM6-T0/2/06492dd3a022e4a4f9e437a943dd1d8b

Spoiler Alert

6 Jun 2011•In the News, Legal Issues, Policy Issues, Threats to Wildlife

Coming up this Wednesday: “Impacts of Free Roaming Cats on Native Wildlife,” a Webinar sponsored by the U.S. Fish and Wildlife Service. Registration, from what I can tell, appears to be open to the public—though I’m still awaiting a confirmation e-mail (which will include, I hope, some clarification re: time zone for this “2:00–3:00 pm” event).

The USFWS Website lists the agency’s own Tom Will as the scheduled speaker, and includes the following description:

A rapidly growing feral and unrestrained domestic cat population kills an average of at least 1.5 million birds in the U.S. every day—and even greater numbers of small mammals and herptiles. Every small songbird species is vulnerable at some stage of its life cycle. Despite ample peer-reviewed science documenting the failure of trap-neuter-release (TNR) programs to reduce cat populations or address wildlife depredation, TNR and outdoor cat feeding colonies continue to be marketed to city councils, county boards, and state legislatures as a viable option. As a result, TNR feeding colonies are proliferating across the landscape at such an alarming rate that wildlife conservation programs intended to create source habitat are being rendered ineffectual in many areas. In this presentation, I briefly review the science on the effects of outdoor cats on wildlife and the ineffectiveness of TNR programs. Then, examples of the decision making process leading to community endorsement of TNR provide some insight into the roadblocks to effective conservation action. Finally, I offer a suite of strategic conservation actions at national agency, community, and home scales whereby the Service and its partners might work effectively to reduce the negative effects of irresponsible civic TNR decisions on wildlife trust resources.

I expect, given Will’s apparent interest in the science surrounding this issue, that he’ll shed some light on the origins of that 1.5 million birds/day predation rate—which, translated to an annual figure, is pretty close to what the American Bird Conservancy uses in The American Bird Conservancy Guide to Bird Conservation: “532 million birds killed annually by outdoor cats.” [1]

This Webinar, then, could be our chance to see the science behind the number. Or not—if this week’s presentation is anything like the one Will gave in 2010 to the Bird Conservation Alliance (which, according to its Website, is “facilitated by” ABC). Last year’s show, “What Can Federal Agencies Do? Policy Options to Address Cat Impacts to Birds and Their Habitats,” available (downloadable PDF) via the Animal Liberation Front Website, was short on science and long on rhetoric (and plenty of misinformation, too).

Now, I’ve no way of knowing what Will is going to present this week. So, although these things tend to be remarkably predictable, I’ll reserve judgment.

That said, it seems like a good time for a quick look at his 2010 material.

Birds of a Feather
As it happens, Tom Will is among those Nico Dauphine thanks “for helpful information, advice, ideas, and discussion in researching this subject” in her 2009 Partners In Flight conference paper. [2] And much of the material Will used last year was shown a year earlier by Dauphine, in her infamous “Apocalypse Meow” presentation. (The similarities are uncanny, actually: identical background color, many of the same images, etc.)

Death by (Faulty) Statistics
Like Dauphine, Will includes the graph (shown below) from the second edition of Frank Gill’s Ornithology, suggesting, apparently, that predation by cats far exceeds all other sources of mortality combined (a claim Dauphine made in her 2008 letter to the editor of the St. Petersburg Times).

Figure 24-4--Human-related causes of mortality (Gill's Ornithology)

But, as I’ve explained previously, Gill’s cat “data” aren’t data at all, but the indefensible (in terms of its lack of scientific merit, but also its almost palpable bias) guesswork of Rich Stallcup, co-founder of the Point Reyes Bird Observatory.

All of which raises serious doubts about USFWS’s commitment “to using sound science in its decision-making and to providing the American public with information of the highest quality possible.”

Counting Cats
The more intriguing visual, though, in Will’s 2010 presentation (shown below) is meant (it seems) to illustrate the relationship between the increasing population of cats and the decreasing populations of bird species over the past 40 years or so.

But, of course, correlation is not the same as causation. I’ll bet that, like cat ownership, membership in the National Audubon Society has risen steadily over the past 40 years—but somehow, I don’t imagine anybody suggesting that bird populations decline as NAS membership climbs.

What first caught my eye was not the the implied relationship between cat numbers and bird numbers, however, but the red dots themselves. The same data were plotted (as shown below) in “What Conservation Biologists Can Do to Counter Trap-Neuter-Return: Response to Longcore et al.,” [3] published last year in Conservation Biology, (among the paper’s 10 co-authors, by the way: Nico Dauphine and Peter Marra).

What Conservation Biologists Can Do--Chart_590px

Look closely at the two graphs, and you’ll see that Will has gotten creative here. His data points (which, I believe, come primarily from the U.S. Census and APPA) are identical to those used in the letter to Conservation Biology, but the vertical scale’s been changed. In Will’s version, the upper right portion of the graph has jumped from 90 million to 150 million cats! (His horizontal axis is shifted slightly, but the impact is nothing by comparison.)

Apparently, Will is combining population data for pet cats with data for feral cats. Trouble is, his “data” for feral cats doesn’t exist. It looks as if Will simply borrowed from Dauphine, who borrowed from David Jessup—whose “estimate” is unattributed.

So much for “using sound science” and “providing the American public with information of the highest quality possible.”

Roaming Charges May Apply
What if Will stuck to what the data actually show? It seems the message is pretty clear: since 1971, the number of pet cats in the U.S. has nearly tripled.

OK, but what does that mean for the nation’s wildlife? Keep in mind: the country’s human population swelled by 43 percent over the same period, taking an enormous toll on wildlife—either directly (e.g., loss of habitat via development, birds colliding with buildings, etc.) or indirectly (e.g., increased pollution and pesticide use).

Let’s set all that aside for the moment, though, and get back to pet cats. Even if the graphs accurately reflect the upward trend of cat ownership in the U.S. (and I’m not sure they do), they grossly misrepresent the threat to wildlife—which, presumably, is the point.

Simply put, there are not three times as many pet cats outdoors today.

The data I have, from the American Pet Products Association, [4] go back only to 1998. At that time, 56 percent of cat owners responding to APPA’s National Pet Owners Survey indicated that their cats were indoors-only; in 2008, that figured had climbed to 64 percent.

With an estimated 89.6 million pets cats in the U.S. in 2010, then, that means that about 32.4 million cats are outdoors for at least some part of the day (and approximately half of those are outside for less than three hours each day [5, 6]).

What was the proportion in 1971? Unfortunately, I’ve been unable to find any survey results from the 1970s or 1980s. All we can do it guess.

Let’s say that in 1971 just one-third of pet cats were kept indoors exclusively (the very situation Dauphine would have us believe we’re facing today). That means 21.5 million cats were free-roaming for at least some part of the day.

Again, this is a guess—not an unreasonable one, but a guess anyhow. Still, the implications are significant. While it’s true that the number of pet cats has tripled over the past 40 years, the number that are free-roaming has probably increased by only 50 percent or so.

Prosecution or Persecution?
Finally, I’m curious to see if Will’s “suite of strategic conservation actions” will include, as his 2010 presentation suggests, threatening those who conduct or officially endorse TNR with prosecution under the Endangered Species Act (ESA) and the Migratory Bird Treaty Act (MBTA).

This has become a common tactic in recent years (see, for example, the Florida Keys National Wildlife Refuges Complex Integrated Predator Management Plan/Draft Environmental Assessment, released earlier this year), though it goes back to at least 2003, when Pamela Jo Hatley, then a law student, suggested the possibility.

(One wonders if USFWS, the agency responsible for drafting the Keys Predator Management Plan, could be prosecuted under the ESA and MBTA in the event—not unlikely—that a large-scale round-up of feral cats resulted in a population explosion of rats, which in turn decimate the very species the Plan claims to protect.)

• • •

As a say, I’m not going to critique Will’s presentation until he’s had the chance to give it. Indeed, he may very well deliver on the science review, policy insights, conservation actions, etc. If what he provided the BCA is any indication, though, the man’s got his work cut out for him.

Literature Cited
1. Lebbin, D.J., Parr, M.J., and Fenwick, G.H., The American Bird Conservancy Guide to Bird Conservation. 2010, London: University of Chicago Press.

3. Lepczyk, C.A., et al., “What Conservation Biologists Can Do to Counter Trap-Neuter-Return: Response to Longcore et al.” Conservation Biology. 2010. 24(2): p. 627–629. www.abcbirds.org/abcprograms/policy/cats/pdf/Lepczyk-2010-Conservation%2520Biology.pdf

4. APPA, 2009–2010 APPA National Pet Owners Survey. 2009, American Pet Products Association: Greenwich, CT. http://www.americanpetproducts.org/pubs_survey.asp

5. Clancy, E.A., Moore, A.S., and Bertone, E.R., “Evaluation of cat and owner characteristics and their relationships to outdoor access of owned cats.” Journal of the American Veterinary Medical Association. 2003. 222(11): p. 1541-1545. http://avmajournals.avma.org/doi/abs/10.2460/javma.2003.222.1541

6. Lord, L.K., “Attitudes toward and perceptions of free-roaming cats among individuals living in Ohio.” Journal of the American Veterinary Medical Association. 2008. 232(8): p. 1159-1167. http://www.avma.org/avmacollections/feral_cats/javma_232_8_1159.pdf

Perfectly Comfortable? I’m Not.

31 May 2011•Uncategorized

As many of you know, the National Zoo has shown no signs of suspending Nico Dauphine, despite her recent arrest on charges of attempted animal cruelty. As a result, at least two petitions are being circulated—one by Alley Cat Rescue, and another by Alley Cat Allies.

I encourage readers to sign both petitions, and also to send letters (an online form is available here). Below is my letter to National Zoo director Dennis Kelly:

Dear Dennis Kelly,

As you know, the National Zoo’s mission emphasizes leadership—in animal care, science, and education—as well as “the highest quality animal care.” But recent events indicate that Zoo management has lost sight of this noble mission.

Indeed, allowing Dr. Nico Dauphine—recently charged with attempted animal cruelty in connection with the poisoning of cats in her neighborhood—to continue her work for the Zoo’s Migratory Bird Center demonstrates a profound lack of leadership, and suggests a remarkably narrow view of “animal care.”

Comments made last week by the Zoo’s associate director of communications, Pamela Baker-Masson, only made matters worse—suggesting that Zoo management isn’t even aware of the research Dauphine is conducting. Baker-Masson told ABC News:

“We know what she’s doing would in no way jeopardize our animal collection at the National Zoo or jeopardize wildlife, so we feel perfectly comfortable that she continue her research.”

But, according to the Migratory Bird Center’s Website, Dauphine’s “current project examines predator-prey dynamics in an urban matrix in collaboration with citizen scientists at Neighborhood Nestwatch.”

The predators in this case are, of course, house cats. And, according to an online application form she’s been using to recruit field assistants (the form was recently removed from the Migratory Bird Center’s Website), Dauphine is asking participating citizen scientists to put cameras on their cats.

And still, the National Zoo feels “perfectly comfortable that she continue her research.” What kind of message does this send to the local community, and to the nation as a whole?

The Smithsonian’s 2009 Annual Report indicates that 75 percent of the organization’s revenue comes from “federal appropriations” (63 percent) and “government grants and contracts” (12 percent). One way or another, these are tax dollars. In standing by Dauphine, then, the National Zoo is violating the trust of its primary funding source: the American people (among whom, 38.9 million households own cats).

Finally, the National Zoo should use the current crisis as an opportunity to review its hiring practices. I think it’s safe to say that Dauphine’s reputation preceded her when she joined your organization. Her extreme position against TNR—and free-roaming cats in general—is well documented. As is her habit of misrepresenting the science surrounding the issue.

In her February 10, 2008, letter to the editor of the St. Petersburg Times, for example, Dauphine—who identifies herself as “a scientist who has studied this issue”—makes an outlandish claim:

“In North America, cats may be the single biggest direct cause of bird mortality, far outnumbering all other causes (including human hunters) put together!”

Not even the American Bird Conservancy—which has, for the past 15 years, taken every opportunity to demonize free-roaming cats—goes this far.

And yet, the National Zoo has Dauphine, together with Dr. Peter Marra (who, in a letter co-authored with Dr. Dauphine, has called TNR “cat hoarding without walls.”), [1] researching the hunting habits of house cats. All of which raises questions about the rigor and validity of the research being conducted—not to mention the integrity of those involved.

As the National Zoo’s director, you have the responsibility to address these issues. I am, therefore, asking you to start by suspending Dr. Dauphine until the charges of attempted animal cruelty are dropped, proven to be unfounded, or in some other way resolved.

Respectfully,

Peter J. Wolf
Independent Researcher/Analyst
Vox Felina

Nico Dauphine Update

25 May 2011•Cats and Birds, In the News, Legal Issues

Photo from an online application form Nico Dauphine was (until Tuesday) using to hire field assistants, whose duties include “assist[ing] citizen participants in deploying miniature collar-mounted cameras on their free-roaming pet domestic cats.”

Tuesday, while animal welfare organizations across the country were issuing statements condemning the alleged cruelty and urging justice in the case, Nico Dauphine’s employer was expressing a rather remarkable lack of concern.

Scott Giacoppo, Vice President External Affairs & Chief Programs Officer for the Washington Humane Society, questioned whether Dauphine should remain employed by the National Zoo in the event she’s convicted.

“If she did do this,” Giacoppo told ABC News, “then we naturally would be concerned about her being around all animals. Whoever would do such a thing is a threat to all animals. It is a slow and painful death. It was callous and complete disregard for animals’ well being.”

According to ABC News, evidence in the case is the result of WHS’s “month-long investigation monitoring video surveillance and matching card swipes in and out of an apartment complex near the scene of the alleged crime.”

The Humane Society of the United States [not affiliated with WHS] issued a statement “applaud[ing] the Washington Humane Society for its investigation” and “urg[ing] full prosecution by the U.S. Attorney’s Office if warranted.”

Alley Cat Allies president Becky Robinson called the story “troubling.” “Intentionally killing cats is illegal and cruel. Criminal charges in this case are appropriate and necessary.”

“Alley Cat Rescue vehemently disagrees with keeping Dauphine in her current position at the National Zoo,” reads a statement posted on the organization’s blog . “[ACR] believes she should be removed until an investigation into these allegations of animal cruelty has been completed.” ACR has started a petition aimed at getting Dauphine removed.

Meanwhile, a spokesperson for the National Zoo, which oversees the Smithsonian’s Migratory Bird Center—where Dauphine works with her advisor, Peter Marra—was trying to play down the fact that one of its researchers is charged with attempted animal cruelty.

Pamela Baker-Masson, associate director of communications , told ABC News: “We know what she’s doing would in no way jeopardize our animal collection at the National Zoo or jeopardize wildlife, so we feel perfectly comfortable that she continue her research.”

Which begs the question: Does Baker-Masson actually know what Dauphine’s research is?

As I indicated Monday, when this story broke, Dauphine’s “current project examines predator-prey dynamics in an urban matrix in collaboration with citizen scientists at Neighborhood Nestwatch.”

The predators, in this case, are (not surprisingly) house cats. And, according to an online application form (which mysteriously disappeared from the Smithsonian’s Website Tuesday) she’s been using to recruit field assistants, Dauphine is asking participants to put cameras on their cats—thus allowing her team to monitor the cats’ every move.

Granted, Dauphine’s yet to have her day in court, but still—at this point, who in their right mind would allow their cat to participate in any study sponsored by the Migratory Bird Center.

It’s Not the Media, It’s the Message

19 Mar 2011•In the News, The Cat Debate, Threats to Wildlife

To hear The Wildlife Society’s staunch opponents of TNR tell it, the media’s just not interested in stories about “the impacts of free-ranging and feral cats on wildlife.”

“This January when thousands of blackbirds fell from the sky in Arkansas, articles about mass extinctions and bird conservation were a dime-a-dozen. When the Deepwater Horizon oil spill killed 6,000 birds between April to October 2010, news organizations ran ‘Breaking News’ about the negative impacts on the environment. Meanwhile it is estimated that one million birds are killed everyday by cats, and the only news organizations covering it are small, local branches. The bigger problem is being shuffled to the backburner for more sensational news.”

According to The Wildlife Society (TWS), however, “the bigger problem” is “greater than almost any other single-issue.”

In their effort to get the issue on the front burner, TWS has “gathered the facts about these cats, and published them in the Spring Issue of The Wildlife Professional in a special section called ‘The Impact of Free Ranging Cats.’” (available free via issuu.com)

Thus armed, readers are expected to, as it says on the cover, “Pick One: Outdoor Cats or Conservation”

Back Burner or Hot Topic?
Before we get to the “facts,” it’s worth looking back over the past 15 months to see just how neglectful the media have been re: “the bigger problem.”

January 9, 2010: Travis Longcore, science director for the Urban Wildlands Group, tells Southern California Public Radio: “Feral cats are documented predators of native wildlife. We do not support release of this non-native predator into our open spaces and neighborhoods, where they kill birds and other wildlife.”

January 17, 2010 Longcore, whose Urban Wildlands Group was lead plaintiff in a lawsuit aimed to put an end to publicly supported TNR in Los Angeles, tells the L.A. Times: “It’s ugly; it’s gotten very vicious. It’s not like we’ve got a vendetta here. This is a real environmental issue, a real public health issue.” In the same story, American Bird Conservancy’s Senior Policy Advisor, Steve Holmer, tells the Times: “The latest estimates are that there are about . . . 160 million feral cats [nationwide]… It’s conservatively estimated that they kill about 500 million birds a year.”

May 8, 2010: Austin American-Statesman writer Mike Leggett devoted his column to the defense of his cat-killing neighbor. According to Leggett, the man’s killed more than 20 feral cats—he “just cannot tolerate what cats do to wild birds.” And, offers Leggett, “none of us should.”

June 17, 2010: An Associated Press story about a proposed feeding ban in Barre, VT, (subsequently picked up by MSNBC) includes multiple quotes from ABC’s Cats Indoors! campaign.

September 10, 2010: Jonathan Franzen, winner of the 2001 National Book Award and a Pulitzer Prize finalist the following year—also an ABC board member—tells Studio 360 host Kurt Andersen that housecats kill a million songbirds a day, just as Franzen depicts in his latest novel Freedom. “Minimum, minimum,” insists Franzen. “Cats should be indoors.”

September 30, 2010: “Scientists are quietly raging about the effects that cats, both owned and stray, are having on bird populations,” claims Washington Post columnist Adrian Higgins. “It’s not an issue that has received much attention, but with an estimated 90 million pet cats in the United States, two-thirds of them allowed outdoors, the cumulative effect on birds is significant, according to experts.” Higgins’ story is riddled with misinformation, courtesy of the American Bird Conservancy (ABC), The Wildlife Society, and Dauphine and Cooper’s 2009 Partners in Flight paper.

October 2010: The Smithsonian Migratory Bird Center posts “Baby Catbird Survival” on its Website (the page is currently “under renovation”), claiming that cats were responsible for “alarmingly high rates of nest predation and fledging [sic] mortality.”The evidence? It seems “several guilty-looking cats were found in close proximity to dead birds. Our guess is that closer examination would have revealed feathers in their whiskers.”

December 20, 2010: Feral cats are included among “The World’s Worst Invasive Mammals,” as determined by the Smithsonian (which, by the way, has yet to approve my comment). The article’s misinformation is as sensational as its headline: “In addition to carrying rabies, 62 to 82 percent of cats in a recent study tested positive for toxoplasmosis.”

December 2010: “Feral Cats and Their Management” is picked up by numerous media outlets, many of which mistake it for actual research.

January 17, 2011: Toronto Star reporters do the dirty work for TNR opponent David Bird (“The more cats, the fewer birds”) and Maureen Palmer, director of the recently released documentary Cat Crazed:

“Palmer said one of the most ‘heartbreaking’ scenes during filming was at a volunteer spay-neuter clinic in Los Angeles that sterilized 80 ferals a day. She said most of the cats had infections that never healed, as well as broken bones, large abscesses around their teeth and mange.” (A claim easily discredited, if only the reporters had bothered to check.)

January 2011: Utah Representative Curtis Oda sponsors HB 210, which would permit “the humane shooting of an animal in an unincorporated area of a county, where hunting is not prohibited, if the person doing the shooting has a reasonable belief that the animal is a feral animal.”

March 7, 2011: Once again, the Smithsonian is promoting Peter Marra’s gray catbird research. Among the first to pick it up is Discovery News. Two days later, the story is featured on Science at the Smithsonian, “a new Website from the Smithsonian Office of Public Affairs.”

Yet, the folks at TWS would have us believe that “the only news organizations covering [the cat-bird issue] are small, local branches.” As is often the case, their story doesn’t hold up well alongside the facts.

Indeed, other than when Higgins got Executive Director/CEO Michael Hutchins’ name wrong, it’s hard to see what TWS has to complain about.

The Art of Selling Science
“After years of arguments,” laments Nico Dauphine and Robert Cooper, recalling last year’s decision by Athens, GA, to adopt TNR, “the vote was cast: 9–1 in favor of the ordinance, with an additional 7–3 vote establishing a $10,000 annual budget to support the TNR program.”

“How could this happen in a progressive community like Athens, Georgia, home to one of the nation’s finest university programs in wildlife science? The answer is a complex mix of money, politics, intense emotions, and deeply divergent perspectives on animal welfare… If we’re going to win the battle to save wildlife from cats, then we’ll need to be smarter about how we communicate the science.” [1]

Something tells me this “smarter” communication doesn’t allow for much in the way of honesty and transparency—attributes already in short supply.

Old Habits
“The Impact of Free Ranging Cats” has given its contributors the opportunity to revive and reinforce a range of dubious claims, including the ever-popular exaggerations about the number of free-roaming cats in the environment.

According to Dauphine and Cooper, “The number of outdoor pet cats, strays, and feral cats in the U.S. alone now totals approximately 117 to 157 million,” [1] an estimate rooted in their earlier creative accounting. Colin Gillin, president of the American Association of Wildlife Veterinarians, who penned this issue’s “Leadership Letter” (more on that later), follows suit, claiming “60 million or more pet cats are allowed outdoors to roam free.” [2]

The American Pet Products Association 2008 National Pet Owners Survey, though, indicates that 64 percent of pet cats are indoor-only during the daytime, and 69 percent are kept in at night [3]. Of those that are allowed outdoors, approximately half are outside for less than three hours each day. [4, 5]

This information is widely available—and has been for years—yet many TNR opponents continue to inflate by a factor of two the number of free-roaming pet cats.

And it only gets worse from here.

Dense and Denser
Not content to inflate absolute cat numbers, Dauphine and Cooper go on to misrepresent research into population demographics as well. “Local densities can be extremely high,” they write, “reaching up to 1,580 cats per square kilometer in urban areas.” [1] In fact, the very paper they cite paints a rather different picture. For one thing, there’s quite a range involved: 132–1,579 cats per square kilometer (a point recognized by Yolanda van Heezik, another contributor to the special issue [6].)

Also, this is a highly skewed distribution—there are lots of instances of low/medium density, while high densities are far less common. As a result, the median (417) is used “as a measure of central tendency” [7] rather than the mean (856). So, although densities “reaching up to 1,580 cats per square kilometer in urban areas” were observed, more than half fell between 132 and 417 cats per square kilometer (or 51–161 cats per square mile).

Even more interesting, however, are what Sims et al. learned when they compared bird density and cat density: in many cases, there were more birds in the very areas where there were more cats—even species considered especially vulnerable to predation by cats. It may be, suggest Sims et al., that, because high cat density corresponds closely to high housing density, this measure is also an indication of those areas “where humans provide more supplementary food for birds.” [7]

Another explanation: “consistently high cat densities in our study areas… and thus uniformly high impacts of cat populations on urban avian assemblages.” [7] (Interestingly, the authors never consider that they might be observing uniformly low impacts.)

The bottom line? It’s difficult enough to show a direct link between observed predation and population impacts; suggesting a causal connection between high cat densities and declining bird populations is misleading and irresponsible. (Not that Dauphine and Cooper are the only ones to attempt it; recall that no predation data from Coleman and Temple’s “Wisconsin Study” were ever published, despite numerous news stories in which Temple referred to their existence in some detail [8–10].)

Predation Pressure
Dauphine and Cooper make a similar leap when, to buttress their claim that “TNR does not reduce predation pressure on native wildlife,” [1] they cite a study not about predation, but about the home ranges of 27 feral cats on Catalina Island.

While it’s true that the researchers found “no significant differences… in home-range areas or overlap between sterilized and intact cats,” [11] this has as much due to their tiny sample size as anything else. And the difference in range size between the four intact males and the four sterilized males was—while not statistically significant—revealing.

The range of intact males was 33–116 percent larger during the non-breeding season, and 68–80 percent larger during the breeding season. In his study of “house-bound” cats, Liberg, too, found differences: “breeding males had ranges of 350–380 hectares; ranges of subordinate, non-breeding males were around 80 hectares, or not much larger than those of females.” [12]

All of which suggests smaller ranges for males that are part of TNR programs. What any of this has to do with “predation pressure on native wildlife,” however, remains an open question.

On the other hand, Castillo and Clarke (whose paper Dauphine and Cooper cite) actually documented remarkably little predation among the TNR colonies they studied. In fact, over the course of approximately 300 hours of observation (this, in addition to “several months identifying, describing, and photographing each of the cats living in the colonies” [13] prior to beginning their research), Castillo and Clarke “saw cats kill a juvenile common yellowthroat and a blue jay. Cats also caught and ate green anoles, bark anoles, and brown anoles. In addition, we found the carcasses of a gray catbird and a juvenile opossum in the feeding area” [13].

Another of Dauphine and Cooper’s “facts”—that “TNR does not typically reduce feral cat populations”—is contradicted by another one of the studies they cite. Contrary to what the authors suggest, Felicia Nutter’s PhD thesis work showed that “colonies managed by trap-neuter-return were stable in composition and declining in size throughout the seven year follow-up period.” [14]

Indeed, Nutter observed a mean decrease of 36 percent (range: 30–89 percent) in the six TNR colonies they studied over two years. By contrast, the three control colonies increased in size an average of 47 percent. [15]

Additional TNR success stories Dauphine and Cooper fail to acknowledge:

Natoli et al. reported a 16–32 percent decrease in population size over a 10-year period across 103 colonies in Rome—despite a 21 percent rate of “cat immigration.” [16]

As of 2004, ORCAT, run by the Ocean Reef Community Association (in the Florida Keys), had reduced its “overall population from approximately 2,000 cats to 500 cats.” [17] According to the ORCAT Website, the population today is approximately 350, of which only about 250 are free-roaming.

Toxoplasma gondii
In recent years, Toxoplasma gondii has been linked to the illness and death of marine life, primarily sea otters [18], prompting investigation into the possible role of free-roaming (both owned and feral) cats. [19, 20] But if, as the authors claim, “the science points to cats,” then it does so rather obliquely, an acknowledgement Jessup and Miller make begrudgingly:

“Based on proximity and sheer numbers, outdoor pet and feral domestic cats may be the most important source of T. gondii oocysts in near-shore marine waters. Mountain lions and bobcats rarely dwell near the ocean or in areas of high human population density, where sea otter infections are more common.” [21, emphasis mine]

Correlation, however, is not the same as causation. And not all T. gondii is the same.

In a study of southern sea otters from coastal California, conducted between 1998 and 2004, a team of researches—including Jessup and Miller—found that 36 of 50 otters were infected with the Type X strain of T. gondii, one of at least four known strains. [22] Jessup and Miller were also among 14 co-authors of a 2008 paper (referenced in their contribution to “The Impact of Free Ranging Cats”) in which the Type X strain was linked not to domestic cats, but to wild felids:

“Three of the Type X-infected carnivores were wild felids (two mountain lions and a bobcat), but no domestic cats were Type X-positive. Examination of larger samples of wild and domestic felids will help clarify these initial findings. If Type X strains are detected more commonly from wild felids in subsequent studies, this could suggest that these animals are more important land-based sources of T. gondii for marine wildlife than are domestic cats.” [20, emphasis mine]

Combining the results of the two studies, then, nearly three-quarters of the sea otters examined as part of the 1998–2004 study were infected with a strain of T. gondii that hasn’t been traced to domestic cats. (I found this to be such surprising news that, months ago, I tried to contact Miller about it. Was I missing something? What studies were being conducted that might confirm or refute these finings? Etc. I never received a reply.)

As Miller et al. note, “subsequent studies” are in order. And it’s important to keep in mind their sample size was quite small: three bobcats, 26 mountain lions, and seven domestic cats (although the authors suggest at one point that only five domestic cats were included).

Still, a recently published study from Germany seems to support the hypothesis that the Type X strain isn’t found in domestic cats. Herrmann et al. analyzed 68 T. gondii-positive fecal samples (all from pet cats) and found no Type X strain. [23] (It’s interesting to note, too, that only 0.25 percent of the 18,259 samples tested positive for T. gondii.)

This is not to say that there’s no connection between domestic cats and Toxoplasmosis in sea otters, but that any “trickle-down effect,” as Jessup and Miller describe it, is not nearly as well understood as they imply. There’s too much we simply don’t know.

Money and Politics
I agree with Dauphine and Cooper that science is only part of the TNR debate—that it also involves “a complex mix of money, politics, intense emotions, and deeply divergent perspectives on animal welfare.” And I agree with their assessment of the progress being made by TNR supporters:

“Advocates of TNR have gained tremendous political strength in the U.S. in recent years. With millions of dollars in donor funding, they are influencing legislation and the policies of major animal-oriented nonprofit organizations.” [1]

What I find puzzling is Dauphine’s rather David-and-Goliath portrayal of the “cat lobby” (my term, not hers) they’re up against—in particular, her complaint, “promotion of TNR is big business, with such large amounts of money in play that conservation scientists opposing TNR can’t begin to compete.” [24]

The Cat Lobby
In “Follow the Money: The Economics of TNR Advocacy,” she notes that Best Friends Animal Society, “one of the largest organizations promoting TNR, took in over $40 million in revenue in 2009.” [24] Fair enough, but this needs to be weighed against expenses of $35.6 million—of which $15.5 million was spent on “animal care activities.”

But Dauphine’s got it wrong when she claims that Best Friends “spent more than $11 million on cat advocacy campaigns that year.” [24] Their financials—spelled out in the same document Dauphine cites—are unambiguous: $11.7 million in expenditures went to all “campaigns and other national outreach.” Indeed, there is no breakdown for “cat advocacy campaigns.”

Dauphine does a better job describing Alley Cat Allies’ 2010 financials: of the $5.2 million they took in, $3.3 million was spent in public outreach. But she’s overreaching in suggesting that their “Every Kitty, Every City” campaign is nationwide. For now, at least, it’s up and running in just “five major U.S. cities.”

Echoing Dauphine’s concerns, Florida attorney Pamela Jo Hatley decries ORCAT’s resources: “At a meeting hosted by the Ocean Reef Resort in June 2004,” recalls Hatley, “I learned that the ORCAT colony then had about 500 free-ranging cats, several paid employees, and an annual operating budget of some $100,000.” [25]

What Hatley fails to mention is how those resources have been used to make ORCAT a model for the rest of the country—using private donations. Hatley doesn’t seem to object to the U.S. Fish and Wildlife Service shelling out $50,000—of tax dollars—in 2007 to round up fewer than 20 cats (some of which were clearly not feral) along with 81 raccoons (53 of which were released alive) in the Florida Keys. [26, 27]

Following the Money
According to their 2008 Form 990, ORCAT took in about $278,000 in revenue, compared to $310,000 in expenses. How does that compare to some of the organizations opposing TNR? A quick visit to Guidestar.com helps put things in perspective.

In 2009, ABC took in just under $6 million, slightly more than their expenses.

TWS had $2.3 million in revenue in 2009, which was more than offset by expenses of $2.5 million.

Friends of the National Zoo, which oversees the Smithsonian Migratory Bird Center, showed $15 million in revenue, just exceeding their 2009 expenses of $14.7 million. (The Smithsonian Institute topped $1 billion in both the revenue and expense categories.)

And the National Audubon Society took in $61.6 million in 2008 (the most recent year for which information is available). And, despite expenses in excess of $86 million, finished the year with more than $255 million in net assets.

These numbers clearly don’t reflect the funding each organization dedicates to opposing TNR—but neither do they offer any evidence that, as Dauphine argues, “conservation scientists opposing TNR can’t begin to compete.”

Intense Emotions
Nobody familiar with the TNR debate would suggest that it’s not highly emotional. How can it be otherwise? Indeed, the very idea of decoupling our emotions from such important discourse is rather absurd.

Having an emotional investment in the debate does not, however, make one irrational or stupid.

“On the surface,” suggest Dauphine and Cooper, their tone unmistakably condescending, “TNR may sound reasonable, even logical.” [1] Gillin, for his part, bemoans the way the TNR debate “quickly shifts from statistics to politics to emotional arguments.” [2]

What’s particularly fascinating about all of this—the way TNR supporters are made out to be irrational (if not mentally ill—as in a letter to Conservation Biology last year, when several TNR opponents, including four contributors to “The Impact of Free Ranging Cats,” compared TNR to hoarding [28])—is just how emotionally charged the appeal of TNR opponents is.

Witness the “gruesome gallery of images,” for example, in which “one cat lies dead with a broken leg, one lies dying in a coat of maggots, and another suffers as ticks and ear mites plague its face.” [1] The idea, of course, is that these cats would have been better off if they’d been rounded up and killed “humanely.” A preemptive strike against the inevitability of “short, brutal lives.” (This phrase, which I first saw used by Jessup, [28] has become remarkably popular among TNR opponents.)

But is it that simple? Applying the same logic (if that’s what it is) to pelicans covered in oil, for instance, would we suggest that these birds should either be in captivity or “humanely euthanized”? Obviously not.

Divergent Perspectives on Animal Welfare
While I disagree that “the debate is predominately about whether cats should be allowed to run wild across the landscape and, if not, how to effectively and humanely manage them,” [29] I tend to agree with Lepczyk et al. when they write:

“It’s much more about human views and perceptions than science—a classic case where understanding the human dimensions of an issue is the key to mitigating the problem.” [29]

But, like Dauphine and Cooper, Lepczyk et al. seem more interested in broadcasting their message—loudly, ad nauseam—than in listening. “We need to understand whether people are even aware,” they write, “of the cumulative impact that their actions—choosing to let cats outdoors—can have on wildlife populations.” [29]

Although it’s packaged somewhat “softly,” we’re back to the same old speculative connections between predation and population impacts (familiar terrain for Lepczyk, who tried to connect these same dots in his PhD research). But how much of a connection is there, really? In their review of 61 predation studies, Mike Fitzgerald and Dennis Turner are unambiguous:

“We consider that we do not have enough information yet to attempt to estimate on average how many birds a cat kills each year. And there are few, if any studies apart from island ones that actually demonstrate that cats have reduced bird populations.” [30]

While the tone used by Lepczyk et al. is very much “we’re all in this together,” their prescription for “moving forward” suggests little common ground. (They actually cite that 2010 letter to Conservation Biology [28]—not much of an olive branch.)

“One approach is exemplified in Hawaii,” explain the authors, “where we’ve become part of a large coalition of stakeholders working together with the shared goal of reducing and eventually removing feral cats from the landscape.” [29] So, who’s involved?

“Our diverse group includes individuals from the Humane Society of the United States, the Hawaiian Humane Society, the U.S. Fish and Wildlife Service, the National Park Service, Hawaii’s Department of Land and Natural Resources, and the University of Hawaii. Our team also regularly interacts with other groups around the nation such as regional Audubon Societies and the American Bird Conservancy. Several stakeholders in the group have differing views, such as on whether or not euthanasia or culling is appropriate, or whether people should feed feral cats.” [29]

Other than the Humane Society organizations (whose position on TNR I don’t take for granted, considering they were early supporters of ABC’s Cats Indoors! campaign [31]), I don’t see a real diversity of views in this coalition.

I suppose it’s easy to make room at the table when you’re offering so few seats.

For Dauphine, though, any such collaboration approaches treason. Or selling out, at least.

“In some cases,” she explains, “conservation groups accept funding to join in efforts promoting TNR. The New Jersey Audubon Society, for example, had previously rejected TNR but began supporting it in 2005, acknowledging funding from the Frankenberg and Dodge Foundations for collaboration with TNR groups.” [24]

Dauphine doesn’t go into detail about the amount of funding, and it’s not clear what, if any, role it played in the decision by NJAS (which took in $6.8 million in 2008) to participate in the New Jersey Feral Cat-Wildlife Coalition—the kind of collaborative effort that should be encouraged, not derided:

“From 2002 to 2005, NJAS had actively opposed the practice of TNR in New Jersey. Despite this opposition, municipalities continued to adopt TNR ordinances. In 2005, NJAS, American Bird Conservancy, Neighborhood Cats and Burlington Feral Cat Initiative began exploratory dialogue about implementing standards to protect rare wildlife vulnerable to cat predation in towns which have already adopted TNR programs.” [32]

Message Received, Loud and Clear
Rather than wringing their hands over how to “better communicate the science” [1] or how to better facilitate “legal or policy changes, incentives, and increased education,” [29] TNR opponents might want to reconsider the message itself.

What they are proposing is the killing—on an unprecedented scale—of this country’s most popular pet.

I don’t imagine this tests well with focus groups and donors, of course, but there it is.

These people seem perplexed by a community’s willingness to adopt TNR (“In the end,” lament Lepczyk et al., referring to the decision in Athens, GA, “the professional opinion of wildlife biologists counted no more than that of any other citizen, a major reason for the defeat.” [29]) but fail to recognize how profoundly unpalatable their alternative is.

And, unworkable, too.

Which may explain why it’s virtually impossible to get them to discuss their “plan” in any detail. (I was unsuccessful, for example, in pinning down Travis Longcore during our back-and-forth on the Audubon magazine’s blog and couldn’t get Jessup or Hutchins to bite when I asked the same question during an online discussion of public health risks.)

In light of what’s involved with “successful” eradication programs, I’m not surprised by their eagerness to change the subject.

On Marion Island, it took 19 years to eradicate something like 2,200 cats—using disease (feline distemper), poisoning, intensive hunting and trapping, and dogs. This on an island that’s only 115 square miles in total area, barren, and uninhabited. [33, 34] The cost, I’m sure, was astronomical.

On the sparsely populated (fewer than 1,000, according to Wikipedia) Ascension Island (less than 34 total square miles), a 2003 eradication effort cost nearly $950,000 (adjusted to 2009 dollars). [35]

A 2000 effort on Tuhua (essentially uninhabited, and just 4.9 square miles) ran $78,591 (again, adjusted to 2009 dollars). [35]

Efforts on Macquarie Island (also small—47.3 square miles—and essentially uninhabited) proved particularly costly: $2.7 million in U.S. (2009) dollars. And still counting. The resulting rebound in rabbit and rodent numbers prompted “Federal and State governments in Australia [to commit] AU$24 million for an integrated rabbit, rat and mouse eradication programme.” [36] (To put this into context, Macquarie Island is about one-third the size of the Florida Keys.)

These examples represent, in many ways, low-hanging fruit. By contrast, “the presence of non-target species and the need to safely mitigate for possible harmful effects, along with substantial environmental compliance requirements raised the cost of the eradication.” [37] Eradicating rodents from Anacapa Island, “a small [1.2-square-mile] island just 80 miles from Los Angeles International Airport, cost about $2 million.” [38]

Now—setting aside the horrors involved—how exactly do TNR opponents propose to rid the U.S. of it’s millions of feral cats? [cue the sound track of crickets chirping]

I think the general public is starting to catch on. Even if they fall for the outlandish claims about predation, wildlife impacts, and all the rest—they don’t see anything in the way of a real solution. As Mark Kumpf, former president of the National Animal Control Association, put it in an interview with Animal Sheltering magazine, “the traditional methods that many communities use… are not necessarily the ones that communities are looking for today.” [39]

“Traditional” approaches to feral cat management (i.e., trap-and-kill) are, says Kumpf, akin to “bailing the ocean with a thimble.” [39]

For all their apparent interest—22 pages in the current issue of The Wildlife Professional alone—TWS might as well be handing out thimbles to its members. Although Gillin’s “Leadership Letter” invites “dialogue among all stakeholders,” it offers nothing substantive to advance the discussion:

“If removal and euthanasia of unadoptable feral cats is not acceptable to TNR proponents, then they need to offer the conservation community a logical, science-based proposal that will solve the problem of this invasive species and its effect on wildlife and the environment.” [2]

So much for leadership.

Literature Cited
1. Dauphine, N. and Cooper, R.J., “Pick One: Outdoor Cats or Conservation.” The Wildlife Professional. 2011. 5(1): p. 50–56.

2. Gillin, C., “The Cat Conundrum.” The Wildlife Professional. 2011. 5(1): p. 10, 12.

3. APPA, 2009–2010 APPA National Pet Owners Survey. 2009, American Pet Products Association: Greenwich, CT. http://www.americanpetproducts.org/pubs_survey.asp

4. Lord, L.K., “Attitudes toward and perceptions of free-roaming cats among individuals living in Ohio.” Journal of the American Veterinary Medical Association. 2008. 232(8): p. 1159-1167. http://www.avma.org/avmacollections/feral_cats/javma_232_8_1159.pdf

6. van Heezik, Y., “A New Zealand Perspective.” The Wildlife Professional. 2011. 5(1): p. 70.

7. Sims, V., et al., “Avian assemblage structure and domestic cat densities in urban environments.” Diversity and Distributions. 2008. 14(2): p. 387–399. http://dx.doi.org/10.1111/j.1472-4642.2007.00444.x

8. Wilson, M. (1997). Cats Roaming Free Take a Toll on Songbirds. Boston Globe, p. 11.

9. Seppa, N. (1993, July 22). Millions of Songbirds, Rabbits Disappearing. Wisconsin State Journal, p. 1A.

10. Wozniak, M.D. (1993, August 3). Feline felons: Barn cats are just murder on songbirds. The Milwaukee Journal, p. A1.

11. Guttilla, D.A. and Stapp, P., “Effects of sterilization on movements of feral cats at a wildland-urban interface.”Journal of Mammalogy. 2010. 91(2): p. 482–489. http://dx.doi.org/10.1644/09-MAMM-A-111.1

12. Liberg, O. and Sandell, M., Spatial organisation and reproductive tactics in the domestic cat and other felids, in The Domestic cat: The biology of its behaviour, D.C. Turner and P.P.G. Bateson, Editors. 1988, Cambridge University Press: Cambridge; New York. p. 83–98.

13. Castillo, D. and Clarke, A.L., “Trap/Neuter/Release Methods Ineffective in Controlling Domestic Cat “Colonies” on Public Lands.” Natural Areas Journal. 2003. 23: p. 247–253.

14. Nutter, F.B., Evaluation of a Trap-Neuter-Return Management Program for Feral Cat Colonies: Population Dynamics, Home Ranges, and Potentially Zoonotic Diseases, in Comparative Biomedical Department. 2005, North Carolina State University: Raleigh, NC. p. 224.

15. Stoskopf, M.K. and Nutter, F.B., “Analyzing approaches to feral cat management—one size does not fit all.”Journal of the American Veterinary Medical Association. 2004. 225(9): p. 1361–1364. http://www.ncbi.nlm.nih.gov/pubmed/15552309

www.avma.org/avmacollections/feral_cats/javma_225_9_1361.pdf

16. Natoli, E., et al., “Management of feral domestic cats in the urban environment of Rome (Italy).” Preventive Veterinary Medicine. 2006. 77(3-4): p. 180-185. http://www.sciencedirect.com/science/article/B6TBK-4M33VSW-1/2/0abfc80f245ab50e602f93060f88e6f9

www.kiccc.org.au/pics/FeralCatsRome2006.pdf

17. Levy, J.K. and Crawford, P.C., “Humane strategies for controlling feral cat populations.” Journal of the American Veterinary Medical Association. 2004. 225(9): p. 1354–1360. http://www.avma.org/avmacollections/feral_cats/default.asp

http://www.avma.org/avmacollections/feral_cats/javma_225_9_1354.pdf

18. Jones, J.L. and Dubey, J.P., “Waterborne toxoplasmosis – Recent developments.” Experimental Parasitology. 124(1): p. 10-25. http://www.sciencedirect.com/science/article/B6WFH-4VXB8YT-2/2/8f9562f64497fe1a30513ba3f000c8dc

19. Dabritz, H.A., et al., “Outdoor fecal deposition by free-roaming cats and attitudes of cat owners and nonowners toward stray pets, wildlife, and water pollution.” Journal of the American Veterinary Medical Association. 2006. 229(1): p. 74-81. http://www.avma.org/avmacollections/feral_cats/javma_229_1_74.pdf

20. Miller, M.A., et al., “Type X Toxoplasma gondii in a wild mussel and terrestrial carnivores from coastal California: New linkages between terrestrial mammals, runoff and toxoplasmosis of sea otters.” International Journal for Parasitology. 2008. 38(11): p. 1319-1328. http://www.sciencedirect.com/science/article/B6T7F-4RXJYTT-2/2/32d387fa3048882d7bd91083e7566117

21. Jessup, D.A. and Miller, M.A., “The Trickle-Down Effect.” The Wildlife Professional. 2011. 5(1): p. 62–64.

22. Conrad, P.A., et al., “Transmission of Toxoplasma: Clues from the study of sea otters as sentinels of Toxoplasma gondii flow into the marine environment.” International Journal for Parasitology. 2005. 35(11-12): p. 1155-1168. http://www.sciencedirect.com/science/article/B6T7F-4GWC8KV-2/2/2845abdbb0fd82c37b952f18ce9d0a5f

23. Herrmann, D.C., et al., “Atypical Toxoplasma gondii genotypes identified in oocysts shed by cats in Germany.”International Journal for Parasitology. 2010. 40(3): p. 285–292. http://www.sciencedirect.com/science/article/B6T7F-4X1J771-2/2/dc32f5bba34a6cce28041d144acf1e7c

24. Dauphine, N., “Follow the Money: The Economics of TNR Advocacy.” The Wildlife Professional. 2011. 5(1): p. 54.

25. Hatley, P.J., “Incompatible Neighbors in the Florida Keys.” The Wildlife Professional. 2011. 5(1): p. 52–53.

26. O’Hara, T. (2007, April 3). Fish & Wildlife Service to begin removing cats from Keys refuges. The Key West Citizen, from http://keysnews.com/archives

27. n.a., Lower Florida Keys National Wildlife Refuges Comprehensive Conservation Plan. 2009, U.S. Department of the Interior, Fish and Wildlife Service: Atlanta, GA. http://www.fws.gov/nationalkeydeer/

http://www.fws.gov/southeast/planning/PDFdocuments/Florida%20Keys%20FINAL/TheKeysFinalCCPFormatted.pdf

28. Jessup, D.A., “The welfare of feral cats and wildlife.” Journal of the American Veterinary Medical Association. 2004. 225(9): p. 1377-1383. http://www.ncbi.nlm.nih.gov/pubmed/15552312

http://www.avma.org/avmacollections/feral_cats/javma_225_9_1377.pdf

29. Lepczyk, C.A., van Heezik, Y., and Cooper, R.J., “An Issue with All-Too-Human Dimensions.” The Wildlife Professional. 2011. 5(1): p. 68–70.

30. Fitzgerald, B.M. and Turner, D.C., Hunting Behaviour of domestic cats and their impact on prey populations, in The Domestic Cat: The biology of its behaviour, D.C. Turner and P.P.G. Bateson, Editors. 2000, Cambridge University Press: Cambridge, U.K.; New York. p. 151–175.

31. Berkeley, E.P., TNR Past present and future: A history of the trap-neuter-return movement. 2004, Bethesda, MD: Alley Cat Allies.

32. Stiles, E., NJAS Works with Coalition to Reduce Bird Mortality from Outdoor Cats. 2008, New Jersey Audubon Society. http://www.njaudubon.org/Portals/10/Conservation/PDF/ConsReportSpring08.pdf

33. Bester, M.N., et al., “A review of the successful eradication of feral cats from sub-Antarctic Marion Island, Southern Indian Ocean.” South African Journal of Wildlife Research. 2002. 32(1): p. 65–73.

http://www.ceru.up.ac.za/downloads/A_review_successful_eradication_feralcats.pdf

34. Bloomer, J.P. and Bester, M.N., “Control of feral cats on sub-Antarctic Marion Island, Indian Ocean.” Biological Conservation. 1992. 60(3): p. 211-219. http://www.sciencedirect.com/science/article/B6V5X-48XKBM6-T0/2/06492dd3a022e4a4f9e437a943dd1d8b

35. Martins, T.L.F., et al., “Costing eradications of alien mammals from islands.” Animal Conservation. 2006. 9(4): p. 439–444. http://onlinelibrary.wiley.com/doi/10.1111/j.1469-1795.2006.00058.x/abstract

http://i3n.iabin.net/documents/pdf/Costingeradicationsofalienmammalsfromislands.pdf

36. Bergstrom, D.M., et al., “Indirect effects of invasive species removal devastate World Heritage Island.” Journal of Applied Ecology. 2009. 46(1): p. 73-81. http://onlinelibrary.wiley.com/doi/10.1111/j.1365-2664.2008.01601.x/abstract

http://eprints.utas.edu.au/8384/4/JAppEcol_Bergstrom_etal_journal.pdf

37. Donlan, C.J. and Heneman, B., Maximizing Return on Investments for Island Restoration with a Focus on Seabird Conservation. 2007, Advanced Conservation Strategies: Santa Cruz, CA. http://www.advancedconservation.org/roi/ACS_Seabird_ROI_Report.pdf

38. Donlan, C.J. and Wilcox, C., Complexities of costing eradications, in Animal Conservation. 2007, Wiley-Blackwell. p. 154–156. http://onlinelibrary.wiley.com/doi/10.1111/j.1469-1795.2007.00101.x/abstract

http://www.advancedconservation.org/library/donlan_&_wilcox_2007a.pdf

39. Hettinger, J., Taking a Broader View of Cats in the Community, in Animal Sheltering. 2008. p. 8–9. http://www.animalsheltering.org/resource_library/magazine_articles/sep_oct_2008/taking_a_broader_view_of_cats.html

http://www.animalsheltering.org/resource_library/magazine_articles/sep_oct_2008/broader_view_of_cats.pdf

Catbirds, Cats, and Scapegoats

5 Mar 2011•Cats and Birds, In the News

A Gray Catbird in Madison, Wisconsin, USA. Photo courtesy Wikimedia Commons and John Benson.

Once again, the Smithsonian has apparently put marketing (and perhaps politics, too) ahead of science, reviving a story first posted on the Smithsonian Migratory Bird Center’s (SMBC) Website in October of last year (which has since been removed).

“Alarming number of fledgling, suburban catbirds fall prey to domestic cats, study finds,” reads the headline of the most recent version—posted not on the SMBC site, but as a feature story on Science at the Smithsonian, “a new Website from the Smithsonian Office of Public Affairs.” So what’s changed in the four months since I first commented on the story? Only the publication of the research involved: “Population demography of Gray Catbirds in the suburban matrix: Sources, sinks and domestic cats” by Anne L. Balogh, Thomas B. Ryder, and Peter P. Marra (all of whom are affiliated with the Migratory Bird Center) appeared in the January issue of the Journal of Ornithology.

Whoever wrote the piece for the Smithsonian, though, doesn’t seem to have read the paper.

Indeed, it seems the people responsible for its publication are far more interested in making scapegoats out of the cats than they are in science, or science journalism.

Predation: Real and Imagined
According to the Smithsonian, “Nearly half (47 percent) of the [juvenile catbird] deaths were attributed to domestic cats in Opal Daniels and Spring Park.”

In “Population demography of Gray Catbirds,” the authors report that the Opal Daniels and Spring Park sites accounted for 34 of 42 total juvenile mortalities. [1] The presumption, then, is that 16 (47 percent) are due to cats. However, cats accounted for—at most—just nine of the 42 total mortalities (no breakdown regarding cat kills/site is provided in the paper).

Something doesn’t add up here—and I suspect it’s no accident.

But attributing even nine kills to cats is highly questionable; only six were actually observed. The researchers then attributed three additional kills to cats, claiming: “we are unaware of any other native or non-native predator that regularly decapitates birds while leaving the body uneaten.” [1]

As I’ve pointed out previously, though, a survey of several credible sources [2–5] turns up no supporting evidence. Anderson, describing “predation and its identification,” goes into some detail:

“Domestic cats rarely prey on anything larger than a duck, pheasant, or rabbit. Einarsen (1956) noted their messy feeding behavior. Portions of their prey are often strewn over several hundred square feet in open areas. The meaty portions of large birds are almost entirely consumed leaving loose skin with feathers attached. Small birds are generally consumed, with only the wings, and scattered feathers remaining. Cats usually leave teeth marks on every exposed bone of their prey.” [6]

Raccoons, writes Anderson, are also known to “prey on birds and their eggs. The heads of adult birds are usually bitten off and left some distance from the body (Anon. 1936).” [6]

And it seems to be common knowledge within the birding community that certain species of birds decapitate their prey:

“In urban and suburban settings grackles are the most likely culprits, although jays, magpies, and crows will decapitate small birds, too. Screech-owls and pygmy-owls also decapitate their prey, but, intending to eat them later, they usually cache their victims out of sight.” [7]

“There is little you can do to discourage screech-owls if only because they do their killing under cover of darkness. However, you can recognize their handiwork by looking for partially plucked carcasses of songbirds with the heads missing… Corvids—crows, ravens, jays, and magpies—are well known for their raids on birds’ nests to take eggs and nestlings.” [8] (Interestingly, the author, David M. Bird, was among Marra’s nine co-authors on “What Conservation Biologists Can Do.”)

Balogh, Ryder, and Marra also point out that another “potential nest predator,” the gray squirrel, was more common at the Opal Daniels and Spring Park sites than at the Bethesda site. [1] And roughly three to five times as abundant as cats, based on researcher sightings. Yet the squirrels aren’t mentioned at all in the Smithsonian story.

Populations and Ecological Traps
In addition, Marra’s suggestion that “these suburban areas [are] ecological traps for nesting birds” is contradicted by the results of bird surveys in Maryland.

The Atlas of the Breeding Birds of Maryland and the District of Columbia, for example reports: “during the Atlas period [1983–87], gray catbirds were found throughout the state, including the most heavily urbanized blocks.” The Atlas goes on to note the bird’s “high tolerance for human activity,” concluding that “the gray catbird’s future in Maryland seems secure.” [9]

Data from the Atlas indicate that Maryland’s gray catbird population declined perhaps 7 percent between 1966–1989, a period during which the state’s human population grew approximately 35 percent. (Note: In my previous post on this topic, I mistakenly suggested that the Atlas used Breeding Bird Survey (BBS) data, which is not the case.)

The North American Breeding Bird Survey indicates that Maryland’s gray catbird population has increased about 9 percent between 1966–2009, a period during which the state’s human population grew approximately 57 percent. And data from BBS Route 46110, the nearest to the research sites, also trend upward in recent years. (Note: It’s important to point out that “the survey produces an index of relative abundance rather than a complete count of breeding bird populations.”)

Caption: BBS Data: Gray Catbird Counts Across Maryland, 1966–2007

The Migratory Bird Center’s Website , too, suggests the outlook for the catbird population is quite good:

“To thrive in these [fragmented] habitats birds must have special adaptations such as the ability to respond to frequent nest predation and parasitism and to forage on a wide variety of seasonally available foods. Armed with these adaptations, catbirds are well prepared for the disturbed habitats of the 21st century’s fragmented landscape.”

• • •

Marra revealed his position on free-roaming cats last year in that letter to Conservation Biology opposing TNR. Among the “highlights” were the authors’ assertion that “trap-neuter-return is essentially cat hoarding without walls,” and a demand for “legal action against colonies and colony managers.” The authors also call on conservation biologists to “begin speaking out” against TNR “at local meetings, through the news media, and at outreach events” (a message Marra has obviously taken to heart).

In the past couple of months, the Smithsonian has raised questions about its own stance on free-roaming cats, first with its World’s Most Invasive Mammals story, and now this. In both cases, their reporting has been either careless or intentionally misleading.

According to its Website, the Smithsonian Migratory Bird Center is a “national and international leader in the biology and conservation of migratory birds.” In this case, though, it seems the SMBC—and, by extension, Science at the Smithsonian—have abdicated any leadership role in order to participate in the shameful witch hunt against free-roaming cats.

The Institution’s supporters—and the public at large—expect and deserve better.

Literature Cited

1. Balogh, A., Ryder, T., and Marra, P., “Population demography of Gray Catbirds in the suburban matrix: sources, sinks and domestic cats.” Journal of Ornithology. 2011: p. 1-10. http://dx.doi.org/10.1007/s10336-011-0648-7

http://nationalzoo.si.edu/scbi/migratorybirds/science_article/pdfs/55.pdf

2. Tabor, R., Cats—The Rise of the Cat. 1991, London: BBC Books.

3. Leyhausen, P., Cat behavior: The predatory and social behavior of domestic and wild cats. Garland series in ethology. 1979, New York: Garland STPM Press. xv, 340 p.

4. Fitzgerald, B.M. and Turner, D.C., Hunting Behaviour of domestic cats and their impact on prey populations, in The Domestic Cat: The biology of its behaviour, D.C. Turner and P.P.G. Bateson, Editors. 2000, Cambridge University Press: Cambridge, U.K.; New York. p. 151–175.

5. Turner, D.C. and Meister, O., Hunting Behaviour of the Domestic Cat, in The Domestic Cat: The Biology of Its Behaviour, D.C. Turner and P.P.G. Bateson, Editors. 1988, Cambridge University Press: Cambridge. p. 222.

6. Anderson, T.E., Identifying, evaluating and controlling wildlife damage, in Wildlife Management Techniques. 1969, Wildlife Society: Washington. p. 497–520.

7. Thompson, B., The Backyard Bird Watcher’s Answer Guide. 2008: Bird Watcher’s Digest.

8. Bird, D.M., Crouching Raptor, Hidden Danger, in The Backyard Birds Newsletter. 2010, Bird Watcher’s Digest.

9. Robbins, C.S. and Blom, E.A.T., Atlas of the breeding birds of Maryland and the District of Columbia. Pitt series in nature and natural history. 1996, Pittsburgh, PA: University of Pittsburgh Press. xx, 479 p.

Freedom of the Press (Release)

25 Jan 2011•In the News, The Cat Debate

Among the many news stories, research studies, and government reports brought to my attention last week was an article in Monday’s Toronto Star (thanks, once again, to the good folks at Alley Cat Rescue, who routinely put Google Alerts to shame!). What I find compelling about the article is not its central story (another community struggles with their “feral cat problem”), but the way it illustrates so much of what’s wrong with the free-roaming/feral cat/TNR debate.

In a nutshell, the story is about the town of Oakville changing its bylaws so that cats are no longer allowed to roam free. Wrong-headed policy, in my opinion—but more problematic is the case being made for this policy: what’s being said, how it’s being said, and by whom.

Déjà Vu
One doesn’t have to read further than the first line—“Sylvester and Tweety almost got it right”—to know that this is one of those stories. The kind of story that uses corny references to downplay the implications of a large-scale witch hunt. The kind of story that, frankly, makes it tough to feel much sympathy for a newspaper industry struggling for survival.

“In their cartoon world, the brainy yellow bird always outsmarts the puddy tat. In the real world, the cat kills the canary—and as many as one million birds daily in North America. This is causing a growing, sometimes violent, rift between animal lovers.”

Where that one-million-birds-per-day rate comes from is anybody’s guess, though it sounds awfully familiar—more than likely, one of American Bird Conservancy’s talking points. As for the “violent rift” reporters Mary Ormsby and Jim Wilkes refer to, that comes later.

“The crucial question: Should cats, which are natural hunters, be allowed to freely to roam the streets?”

It’s a fair question, but it’s not as if cats are the only natural hunters found in urban areas. In Chicago, for example, more than 60 coyotes are “roaming parks, alleys, yards and thoroughfares.” (The NPR story claims that coyotes kill area dogs and cats only “every so often,” but in light of Judith Webster’s 2007 paper “Missing Cats, Stray Coyotes: One Citizen’s Perspective,” I’m quite skeptical of such assertions.)

And then, of course, there are the raptors—birds of prey (which are attracted by, among other things, bird feeders—but I’ll get to that shortly).

All Sticks, No Carrots
Progressive animal service organizations have figured out that charging people to house their stray animals (i.e., the “traditional” approach) only hurts the animals and the community at large. Like mandatory spay-neuter laws, it’s great on paper but disastrous in practice.

Yet, this is precisely the direction (read: backwards) Oakville is taking.

“Owners whose loose cats repeatedly end up at the Oakville shelter can be fined $105, plus a $30 town surcharge, a return fee of $25 and $15 for each day the cat stays at the shelter.”

Such a policy virtually guarantees a dramatic increase in intakes—and killing.

“Johanne Golder, executive director of the Oakville and Milton Humane Society, which is contracted by Oakville to provide animal control services… said the mentality that cats are “disposable” pets (unwanted kittens are often abandoned or dumped at shelters) is to blame for the huge feline populations in urban centres.”

Again, a fair point—but I fail to see how the proposed “solution” will improve the situation. And it’s very likely to be a death sentence for the area’s feral cats.

Witch Hunt
Readers who might have similar misgivings are (presumably) set straight when Ormsby and Wilkes explain the threats posed by free-roaming cats:

“The more cats, the fewer birds, said McGill University avian expert David Bird. He said house pets are just as bloodthirsty as untamed ferals—homeless offspring of stray or abandoned cats raised without human contact. Bird (his surname and passion are coincidental, he chirped) estimated well-fed pets alone destroy upwards of a billion birds annually around the world. The American Bird Conservancy (ABC) estimates hundreds of millions are killed in the United States by cats each year but says an exact figure is unclear.”

“Unclear” is right! Anybody even vaguely familiar with the subject would agree that “an exact figure is unclear.” But for Bird to suggest that it’s even possible—or meaningful—is ridiculous. And highly irresponsible. Are we talking about islands or continents? Which part of the world? Rare or common species? Healthy or unhealthy birds? Etc.

And what’s the impact of this predation?

This is ABC’s kind of science: one that strives not for an increased degree of certainty, but greater ambiguity—while at the same time painting a decidedly grim picture. There’s a name for this, of course: propaganda.

Which is precisely what Bird advocates for in “What Conservation Biologists Can Do to Counter Trap-Neuter-Return: Response to Longcore et al.” Along with his nine co-authors, Bird calls on conservation biologists to “begin speaking out” against TNR “at local meetings, through the news media, and at outreach events.” [1]

(Late last year, co-author Peter Marra earned his Propaganda Badge via a Washington Post article, though the research findings he cited there have since been removed from the Smithsonian Migratory Bird Center’s website.)

Rhetoric
Just as important as Bird’s absurd claim, though, is the language used. Indeed, it was the word bloodthirsty that rankled Alley Cat Rescue founder Louise Holton. And there’s plenty more where that came from:

“Bird, the author of The Bird Almanac and Birds of Canada, said the cat-on-bird carnage is as common in quiet residential cul-de-sacs as it is in the countryside.

I’d created a killing field in my own backyard,” recalled the wildlife biology professor, who once spotted four neighbourhood cats stalking finches, woodpeckers, nuthatches, juncos, jays and cardinals nibbling at feeders around his west Montreal home.”

Really, a killing field? Somehow, I don’t think any birds were killed at all. Had any harm come to his birds, I have no doubt Bird would have let readers know in no uncertain terms. This sounds like a Winterism: the careful arrangement of true statements for the purpose of creating a false impression.

Then, too, stalking is not catching or killing, as Fitzgerald and Turner point out:

“Hunting for birds requires stalking, since many species of birds have an up to 360˚ field of view and can detect a cat approaching them from behind [2]… The ‘wait’ just before the pounce is a characteristic element of the cat’s hunting behaviour and many birds also fly away during this ‘wait’ without ever having noticed the cat. Because of these failures, many cats soon give up bird hunting altogether.” [3]

Us and Them
When Bird complains, “I didn’t think it was right for other people’s hobby interest, i.e., owning a pet cat, to impinge upon my interests on my own property,” he betrays his profoundly myopic world view as much as any property rights concern he might have. Cat ownership a hobby interest? Tell that to the 38.2 million U.S. households owning, collectively, something like 94 million cats (my apologies—I don’t have statistics for Canada), which are, increasingly, treated like members of the family.

Is it any wonder “bird people” and “cat people” (classifications I use with some hesitation) have such difficulties communicating?

Bird seems to imply that his bird feeders are inherently benign—but again, that’s from his point of view. “Feeding birds is,” according to the Cornell Lab of Ornithology’s website, “a wonderful way to get to know your birds better! But, bird feeders can also be deadly.”

“Predators (cats, hawks, even dogs) can easily find birds at feeders, dirty feeders can spread disease, feeders can attract non-native, invasive species (house sparrows, brown-headed cow birds, and starlings for instance) which can be detrimental to native birds, and birds might fly away quickly and crash into nearby windows.”

How different is this from the “rationale” typically used to ban the feeding of feral cats? If feeding feral cats is in imposition on the community at large, then so are bird feeders. Should communities require people feeding birds to apply for permits, just as city officials in Yuma, AZ, want to require permits for those conducting TNR?

The way Ormsby and Wilkes tell it, though, birders are up against some kind of powerful cat lobby:

“Bird advocates like him are up against a multi-million-dollar cat-care industry in an animal rights fight that has been tested in U.S. courts, written about in a best-selling novel and spawned an outdoor furniture business to erect enclosed “catios” to give kitty a breath of fresh air.”

Had the reporters followed the money, they would have found a very different story on the advocacy front. According to the most recent data available from Charity Navigator, Alley Cat Allies’ net assets (as of July 2009) were about $2.8 million, compared to $3.7 million for ABC (December 2009). And the National Audubon Society holds in excess of $255 million (June 2009).

All of the sudden, that “multi-million-dollar” characterization doesn’t mean so much.

Cat Crazed
To further their case, Ormsby and Wilkes turn to Maureen Palmer, director of the recently released documentary Cat Crazed (currently unavailable for online streaming outside of Canada, though an audio interview with Palmer is available via the CBC).

“Palmer said one of the most ‘heartbreaking’ scenes during filming was at a volunteer spay-neuter clinic in Los Angeles that sterilized 80 ferals a day. She said most of the cats had infections that never healed, as well as broken bones, large abscesses around their teeth and mange.”

That does sound heartbreaking. But is it true?

I contacted Kim Senn, VP of Operations at FixNation, the clinic Palmer visited for the film. “We are fixing between 70–80 cats a day at FixNation,” she told me via e-mail, “and the overwhelming majority of them are healthy.”

“Less than 5 percent have any medical issues that prevent us from sterilizing them. The common, non-life-threatening issues we do see—like fleas, mange or an occasional abscess—are easily treatable while the cat is here at our clinic, and the cat is left better off than before TNR. And no longer reproducing, which is the best part.”

Immigration Status
Ormsby and Wilkes also touch on one of the most threadbare complaints against free-roaming and feral cats: their “status” as non-native. (Stay tuned for a follow-up story detailing (1) the exact date and time when North America was “pristine,” and (2) precisely how we might return to that mythical Eden.)

“Cats actually never roamed freely in North America until they were introduced by humans. The animals—rodent hunters in the wild—were first domesticated 7,000 years ago in the Middle East and Africa, according to researchers at the University of Nebraska. Those ancient cats evolved into a separate species called the domestic or house cat.”

Of all the possible sources the Toronto Star could consult about the history of the domestic cat, they turned to the authors of “Feral Cats and Their Management”? Isn’t that a bit like consulting Michael Vick about the history of the American Pit Bull Terrier?

“Since cats are not native predators in this part of the world, nesting North American birds have no natural defences against the agile tree climbers. Birds are already under stresses from habitat destruction, pollution, climate change and other animals, such as squirrels, who eat unattended eggs.”

Here, it seems, Ormsby and Wilkes have gone off the deep end, taking an argument used to explain the significant impact cats can have on island populations of birds and other animals—literally—to another level. As Fitzgerald and Turner write:

“Any bird populations on the continents that could not withstand these levels of predation from cats and other predators would have disappeared long ago, but populations of birds on oceanic islands have evolved in circumstances in which predation from mammalian predators was negligible and they, and other island vertebrates, are therefore particularly vulnerable to predation when cats have been introduced.” [3]

At the risk of stating the obvious: birds can fly—at least the ones found in trees can. That’s quite a defense against cats—less so against raptors, of course. Or buildings, pesticides, power lines, wind farms, etc.

Life Imitates Art
Ormsby and Wilkes quote Jonathan Franzen, whose latest novel, Freedom, touches rather directly on, as they put it, “the tension between cat people and bird people.”

“There are many ways for a house cat to die outdoors, including dismemberment by coyote and flattening by a car but when the Hoffbauer family’s beloved pet Bobby failed to come home one early-June evening, and no amount of calling Bobby’s name or searching the perimeter of Canterbridge Estates or walking up and down the county road or stapling Bobby’s Xeroxed image to local trees turned up any trace of him, it was widely assumed on Canterbridge Court that Bobby had been killed by Walter Berglund.”

Actually, Franzen is more of an insider than the reporters let on; Franzen, winner of the 2001 National Book Award and a Pulitzer Prize finalist the following year, sits on ABC’s board of directors, and he wrote the foreword to their recently released book, The American Bird Conservancy Guide to Bird Conservation (brilliant move: ABC has been publishing fiction for years now; at last, they have somebody on board who does it well). Franzen is also a fervent believer.

Ormsby and Wilkes end their article with a brief summary of a 2007 animal cruelty case that made headlines across the U.S. and beyond.

“In Texas five years ago, Jim Stevenson killed a cat. The Galveston ornithologist fatally shot a feral with a .22-calibre rifle, claiming the creature was killing piping plovers, an endangered shorebird species. Stevenson was charged with animal cruelty but walked free in 2007 when jurors failed to come to a decision and a mistrial was declared.”

Rather a dry telling of it, if you ask me. After hearing of bloodthirsty cats, backyard killing fields, and all the rest, aren’t readers entitled to a little more drama? Here, after all, is the only evidence of that “violent rift” Ormsby and Wilkes referred to early on—though, of course, it’s far more one-sided than the reporters suggested with their ominous foreshadowing.

That “feral,” by the way, was part of a colony cared for by John Newland, who, according to Assistant District Attorney Paige Santell, “had fed them, watered them, provided shelter for them, provided toys for them, provided vet care for some of them.”

“This animal suffered a great deal,” says Santell, during an interview with Alley Cat Allies. “That was another part of this case. I mean, this animal did not die right away. It took, you know, 30 to 45 minutes before it died. It was in a terrible amount of pain.”

It must be that Ormsby and Wilkes had hit their word limit already—it’s not as if they don’t like a good story.

The High Cost of a Free Press
Whether Ormsby and Wilkes were unable or unwilling to do this story justice I can’t say, but, as a piece of journalism, their finished product is astonishingly bad.

Not that they’re alone. On the contrary, they have plenty of company.

Last year around this time, when the Los Angeles Times ran a story about the injunction against city-funded TNR, reporter Kimi Yoshino invoked Sylvester and Tweety. And swallowed in one gulp the ridiculous claim by ABC’s Steve Holmer that “there are about . . . 160 million feral cats [nationwide].”

In December, several newspapers treated “Feral Cats and Their Management” as if it were legitimate research. Among the worst were Dale Bowman’s column in the Chicago Sun-Times (December 6), Scott Shalaway’s column (December 12) in the Pittsburgh Post-Gazette, and an editorial (unsigned for good reason) in Lincoln’s Journal-Star (December 7).

And, it just keeps on coming.

Even as I was working on this post, somebody alerted me, via the Vox Felina Facebook page, to an opinion piece in the London Free Press (in which “expert” Theo Hofmann comes up short on both facts and logic: “Cats don’t eat the birds, they just kill them… So they really are causing a great deal of damage…”).

Do news accounts of cats killing a million birds a day turn ordinary citizens into Jim Stevensons? Or reports of 160 million feral cats (one for every two humans in this country!) provoke the kinds of horrors chronicled on the Cat Defender blog? Of course not.

On the other hand, the cumulative effect of such news coverage surely contributes to a misinformed public/electorate. Which, in turn, paves the way for misguided policy. (See, for example, Utah’s House Bill 210, sponsored by Republican Curtis Oda, which proposed to relax “provisions of the Utah Criminal Code relating to animal cruelty and animal torture,” in order to allow, among other things, “the humane shooting or killing of an animal if the person doing the shooting or killing has a reasonable belief that the animal is a feral animal.”)

Journalists have an obligation to approach any story with some healthy skepticism. They owe it to their readers to set aside, as much as possible, their own biases—and challenge those of their sources. To bring to the table some critical thinking and professional integrity.

When it comes to the subject of free-roaming/feral cats/TNR, however, the public rarely gets anything more substantive than a one-sided collection of talking points, sprinkled with cartoon references.

2. Tabor, R., The Wild Life of the Domestic Cat. 1983, London: Arrow Books.

3. Fitzgerald, B.M. and Turner, D.C., Hunting Behaviour of domestic cats and their impact on prey populations, in The Domestic Cat: The biology of its behaviour, D.C. Turner and P.P.G. Bateson, Editors. 2000, Cambridge University Press: Cambridge, U.K.; New York. p. 151–175.

A Tale of Two Cities

27 Oct 2010•Cats and Birds, In the News, Research Protocol

A Gray Catbird in Madison, Wisconsin, USA. Photo courtesy Wikimedia Commons and John Benson.

According to its website, the Smithsonian Migratory Bird Center is a “national and international leader in the biology and conservation of migratory birds.” When it comes to cats and their potential impact on birds, however, the SMBC apparently has a lot to learn.

Actually, they could use some pointers on professionalism, too—and maybe a refresher on the difference between correlation and causation.

Summarizing a recent study of gray catbird fledglings in the Washington, DC area, the SMBC claims that cats were responsible for “alarmingly high rates of nest predation and fledging [sic] mortality.” But there’s no mention of how such a connection was made. Indeed, “Baby Catbird Survival” offers very little in the way of details. Instead, readers are treated to sophomoric commentary:

“… several guilty-looking cats were found in close proximity to dead birds. Our guess is that closer examination would have revealed feathers in their whiskers.”

This is the Smithsonian? What I wouldn’t give to have been in the marketing meeting where “predation humor” was first proposed as an innovative, sure-fire scheme for attracting new donors and research funding.

Catbird Mortality
The study, spanning two summers, was conducted at three sites, two in Takoma Park, MD, and another—apparently less populated with cats—in Bethesda, MD. Somehow—again, no details are given—radio-tracking technology was used to monitor the mortality of young catbirds.

Results indicate that 85% of nests at the Bethesda site were “successful” (i.e., young catbirds survived long enough to leave the nest), compared to only 34% of nests at the Takoma Park sites. At the Bethesda site, 29% of fledglings survived to eight weeks of age, versus 14% at Takoma Park.

Given the rather dramatic nature of these findings, one might expect some explanation of the research methods and analysis techniques employed. Among the numerous questions left unanswered:

How was radio-tracking used to distinguish predation from other forms of mortality—or, more to the point, predation by cats from other forms of predation?
How were the sites selected, and the cats at each site counted?
What other factors (e.g., population density of humans, abundance of other predators, habitat availability and condition, etc.) might have been at work here?
What were the sample sizes employed?

At best—and this is being very generous—the results suggest correlation. But, of course, this is very different from causation.

In Proofiness, author Charles Seife uses the relationship between a country’s energy consumption and the life expectancy of its citizens to illustrate the difference. Plot the data and there is an unmistakable trend: as energy consumption increases, so does life expectancy.

“Yes, it’s true that the more power a society uses, the longer its citizens live, on average. It’s equally true, however, that the more garbage a society produces, the longer its people live. The more automobiles people in a society drive, the more newspapers people in a society read, the more fast food people consume, the more television sets people have, the more time people spend on the Internet…” [1]

So, are the Takoma Park cats the cause of catbird mortality? Who knows.

Who’s In Charge?
Exactly who’s responsible for “Baby Catbird Survival” is another mystery (though anonymity is understandable in this case, as it’s difficult to imagine any respectable scientist claiming ownership of something so flimsy and irresponsible). The researcher who oversaw the project, though, is Peter Marra, the SMBC scientist at the center of a recent Washington Post column (of which I was highly critical).

This, of course, is the same Peter Marra who, along with nine of his colleagues, has argued that “trap-neuter-return is essentially cat hoarding without walls,” and called for “legal action against colonies and colony managers.” [2] The authors also call on conservation biologists to “begin speaking out” against TNR “at local meetings, through the news media, and at outreach events.” [2] It’s a message Marra has obviously taken to heart.

There’s no doubt Marra has an agenda. The question is: how might this bias his research?

Untangling the Research
With so few details to go by, it’s difficult to scrutinize Marra’s catbird study. If it’s published, of course, greater transparency will be required. In the meantime, we do have some useful clues that—along with a little detective work—provide some insight.

Counting Cats
As I indicated previously, it’s hard to imagine that the only difference between the Takoma Park and Bethesda sites was the number of cats. Even if that were the case, though, absolute numbers are hardly the whole story. Numerous studies have demonstrated that predation success varies widely among domestic cats: some catch lots of prey while others catch very few—or none at all. [3–7]

That’s assuming they can get at the prey, of course.

Marra is clear in the Post piece that the (alleged) killers “aren’t feral cats; they’re domestic cats allowed to go outside.” But, contrary to what columnist Adrian Higgins suggests, studies have shown that about two-thirds of cats are indoor-only. [8–11] And of those allowed outside, approximately half spend less than three hours outdoors each day. [9, 10]

How sure can Marra be, then, that the areas’ pet cats are responsible for the deaths of young catbirds?

Predatory Habits
The author of “Baby Catbird Survival” claims that “domestic cats typically only decapitate birds and leave the carcass.” Now, I’ve become quite familiar with the research on the hunting behavior of cats over the past year or so, and recall seeing nothing to this effect. I recently revisited some key sources [12–15] just to be sure, and again found nothing to support this assertion. However, it was brought to my attention that some birds will decapitate their prey:

“In urban and suburban settings grackles are the most likely culprits, although jays, magpies, and crows will decapitate small birds, too. Screech-owls and pygmy-owls also decapitate their prey, but, intending to eat them later, they usually cache their victims out of sight.” [16]

“There is little you can do to discourage screech-owls if only because they do their killing under cover of darkness. However, you can recognize their handiwork by looking for partially plucked carcasses of songbirds with the heads missing… Corvids—crows, ravens, jays, and magpies—are well known for their raids on birds’ nests to take eggs and nestlings.” [17] (Interestingly, the author, David M. Bird, was among Marra’s nine co-authors on “What Conservation Biologists Can Do.”)

Again, how can Marra be so sure the cats are the culprits?

Catbird Population
And finally, what about Marra’s claim, as reported by Higgins, that “catbirds in cat-heavy areas are not able to reproduce at a rate that is sustainable”?

Data from the North American Breeding Bird Survey suggest that Maryland’s gray catbird population declined perhaps 7% between 1966–1989, a period during which the state’s human population grew approximately 35%.

BBS Data: Gray Catbirds Across Maryland (adapted from the Atlas of the breeding birds of Maryland and the District of Columbia)

Even so, the Atlas of the Breeding Birds of Maryland and the District of Columbia—which includes the aforementioned BBS data in its assessment—reports that, “during the Atlas period [1983–87], gray catbirds were found throughout the state, including the most heavily urbanized blocks.” The Atlas goes on to note the bird’s “high tolerance for human activity,” concluding that “the gray catbird’s future in Maryland seems secure.” [18]

Indeed, the SMBC itself echoes the Atlas’ assurances:

“To thrive in these [fragmented] habitats birds must have special adaptations such as the ability to respond to frequent nest predation and parasitism and to forage on a wide variety of seasonally available foods. Armed with these adaptations, catbirds are well prepared for the disturbed habitats of the 21st century’s fragmented landscape.”

Still, statewide figures such as those complied in the Atlas can obscure as much as they reveal. Better to look at the detailed counts from individual survey routes. And it turns out data from BBS Route 46110, the nearest to the Takoma Park and Bethesda sites, actually trend upward in recent years. (Note: It’s important to point out that “the survey produces an index of relative abundance rather than a complete count of breeding bird populations.”)

BBS Data: Gray Catbirds Across Route 46110 (adapted from North American Breeding Bird Survey website)

All of which has me wondering about Marra’s rather dire forecast for the area’s gray catbirds—in terms of the underlying science, of course, but also the possible motives behind such a statement.

* * *

Publishing dodgy science within the scientific community is one thing—hardly excusable, but there is at least a reasonable expectation that one’s peers are in a position to critically evaluate such research—but to package this kind of work for public consumption is truly irresponsible. Like Higgins’ column, “Baby Catbird Survival” is a Trojan Horse: unsubstantiated—and, potentially, highly damaging—claims “wrapped up” as valid science.

Brilliant from a marketing standpoint, maybe—but it’s hardly my idea of leadership.

I’ve attempted to contact both the SMBC and Peter Marra—expressing my concerns with “Baby Catbird Survival,” but also my interest in a more complete accounting of the study’s findings. Unfortunately, neither has responded.

SPECIAL THANKS once again to Louise Holton and Maggie Funkhouser at Alley Cat Rescue for bringing the Washington Post article to my attention.

Literature Cited
1. Seife, C., Proofiness: The Dark Arts of Mathematical Deception. 2010: Viking Adult.

2. Lepczyk, C.A., et al., “What Conservation Biologists Can Do to Counter Trap-Neuter-Return: Response to Longcore et al.” Conservation Biology. 2010. 24(2): p. 627-629.

3. Churcher, P.B. and Lawton, J.H., “Predation by domestic cats in an English village.” Journal of Zoology. 1987. 212(3): p. 439-455.

4. Woods, M., McDonald, R.A., and Harris, S., “Predation of wildlife by domestic cats Felis catus in Great Britain.” Mammal Review. 2003. 33(2): p. 174-188.

5. Baker, P.J., et al., “Impact of predation by domestic cats Felis catus in an urban area.” Mammal Review. 2005. 35(3/4): p. 302-312.

6. Baker, P.J., et al., “Cats about town: is predation by free-ranging pet cats Felis catus likely to affect urban bird populations?“ Ibis. 2008. 150: p. 86-99.

7. Barratt, D.G., “Predation by house cats, Felis catus (L.), in Canberra, Australia. II. Factors affecting the amount of prey caught and estimates of the impact on wildlife.” Wildlife Research. 1998. 25(5): p. 475–487.

8. ABC, Human Attitudes and Behavior Regarding Cats. 1997, American Bird Conservancy: Washington, DC. http://www.abcbirds.org/abcprograms/policy/cats/materials/attitudes.pdf

9. Clancy, E.A., Moore, A.S., and Bertone, E.R., “Evaluation of cat and owner characteristics and their relationships to outdoor access of owned cats.” Journal of the American Veterinary Medical Association. 2003. 222(11): p. 1541-1545.

10. Lord, L.K., “Attitudes toward and perceptions of free-roaming cats among individuals living in Ohio.” Journal of the American Veterinary Medical Association. 2008. 232(8): p. 1159-1167.

11. APPA, 2009–2010 APPA National Pet Owners Survey. 2009, American Pet Products Association: Greenwich, CT.

12. Tabor, R., Cats—The Rise of the Cat. 1991, London: BBC Books.

13. Leyhausen, P., Cat Behavior: The predatory and social behavior of domestic and wild cats. Garland series in ethology. 1979, New York: Garland STPM Press.

14. Fitzgerald, B.M. and Turner, D.C., Hunting Behaviour of domestic cats and their impact on prey populations, in The Domestic Cat: The biology of its behaviour, D.C. Turner and P.P.G. Bateson, Editors. 2000, Cambridge University Press: Cambridge, U.K.; New York. p. 151–175.

15. Turner, D.C. and Meister, O., Hunting Behaviour of the Domestic Cat, in The Domestic Cat: The Biology of Its Behaviour, D.C. Turner and P.P.G. Bateson, Editors. 1988, Cambridge University Press: Cambridge.

16. Thompson, B., The Backyard Bird Watcher’s Answer Guide. 2008: Bird Watcher’s Digest.

17. Bird, D.M., Crouching Raptor, Hidden Danger, in The Backyard Birds Newsletter. 2010, Bird Watcher’s Digest.

18. Robbins, C.S. and Blom, E.A.T., Atlas of the breeding birds of Maryland and the District of Columbia. Pitt series in nature and natural history. 1996, Pittsburgh, PA: University of Pittsburgh Press.

False Confessions

12 Aug 2010•Animal Hoarding, In the News

Whether the latest iteration of reality TV— Animal Planet’s Confessions: Animal Hoarding—is more education, entertainment, or exploitation is a matter of debate. But it’s a safe bet that by streaming “an unflinchingly honest look at a human condition that affects people and animals” into living rooms across the country, a problem too rarely acknowledged (not to mention taken seriously) is now receiving unprecedented attention.

Even if I were a cable subscriber, though, I don’t think I’d be tuning in. Although I was nowhere near the “front lines” of the Great Kitty Rescue, I’ve seen and heard plenty where animal hoarding is concerned. But in reading about Confessions, I was reminded of some remarks included in a comment published earlier this year in Conservation Biology. There, Christopher Lepczyk, Nico Dauphiné, David M. Bird, Sheila Conant, Robert J. Cooper, David C. Duffy, Pamela Jo Hatley, Peter P. Marra, Elizabeth Stone, and Stanley A. Temple compared TNR to animal hoarding:

“The animal welfare community opposes ‘cat hoarding,’ whereby people care for more pets than they can adequately support, because it is considered inhumane. Trap-neuter-return is essentially cat hoarding without walls. Considering that most communities have laws banning animal hoarding, we should consider the same standard for outdoor cats as those that are in a person’s home.” [1]

This strikes me as almost desperate—the latest volley in the kitchen-sink/something-for-everybody approach taken by some TNR opponents. Nevertheless, the analogy—however incongruous—is not new. In 2004, David Jessup made essentially the same comparison:

“Some people are compelled to own and care for excessive numbers of cats. This psychological illness is referred to as ‘collectors psychosis.’ How is the person who must save 25 to 30 cats in their home different from the person who sees themselves [sic] as the savior of 25 to 30 cats in a park? Some ‘cat people’ may be ‘collectors,’ and it is possible that TNR is enabling and supporting some people who need psychologic counseling and assistance.” [2]

Jessup doesn’t burden himself or his audience with even the slightest support for his assertions; his claims are as much conjecture as anything else, his question largely rhetorical. Five years later, Dauphiné and Cooper revisited Jessup’s query, but—despite a handful of references—do no better in terms of its resolution:

“In many cases, the characteristics and behavior of people involved in TNR are suggestive of the psychiatric disorders described in problematic animal hoarding [3]. When presented with alternatives to TNR, such as enclosed sanctuaries, no-kill shelters, and traditional animal control, many such people can be “fiercely protective, retaliatory, and uncooperative,” [4] and will subject public officials and other citizens opposing TNR to harassment and threats [5, 6].” [7]

Animal Hoarding
Dauphiné and Cooper’s argument presupposes that enough is known both about “people involved in TNR” and “the psychiatric disorders described in problematic animal hoarding” for a valid comparison to be made. In fact, very little is known about either one. Randy Frost, whose 2000 article the authors cite, begins by noting, “almost no psychiatric literature exists on this topic.” [3] A year earlier, Gary Patronek (a collaborator of Frost’s, whose work Frost cites throughout his paper) observed: “Unlike the hoarding of inanimate objects, which may be linked with a variety of psychiatric conditions, animal hoarding has not yet been linked with any specific disorder.” [8]

Nevertheless, both Patronek and Frost describe—based on some of the earliest research on the subject—some common characteristics of, and explanatory models for animal hoarding. And provide this definition:

“someone who accumulates a large number of animals; fails to provide minimal standards of nutrition, sanitation and veterinary care; and fails to act on the deteriorating condition of the animals (including disease, starvation and even death) or the environment (severe overcrowding, extremely unsanitary conditions), or the negative effect of the collection on their own health and well-being and on that of other household members.” [8]

This seems to have been the framework for the definition adopted by the Hoarding of Animals Research Consortium (with which Patronek and Frost were involved), which places greater emphasis on two key elements: denial, and accumulation and control:

Having more than the typical number of companion animals;
Failing to provide even minimal standards of nutrition, sanitation, shelter, and veterinary care, with this neglect often resulting in illness and death from starvation, spread of infectious disease, and untreated injury or medical condition;
Denial of the inability to provide this minimum care and the impact of that failure on the animals, the household, and human occupants of the dwelling;
Persistence, despite this failure, in accumulating and controlling animals.

“Saving” 25 or 30 cats, then—whether in one’s home or in the park—does not constitute animal hoarding. As Patronek pointed out during a recent interview on NPR’s Radio Times, “numbers alone don’t define hoarding… you’ve got to have these functional deficits and denial, in combination with the numbers.”

Opponents of TNR (and of free-roaming cats in general) will likely seize upon that second point, arguing that feral cat colonies—by definition—lack adequate care. But the very fact that these cats are part of a TNR program means they’ve been evaluated by veterinary professionals, requiring a concerted effort—sometimes bordering on the heroic—on the part of the trappers and caregivers involved. Some programs perform vaccinations (that this is not standard practice, is, admittedly, a controversial issue); at a minimum, cats deemed too sick to be returned are euthanized.

A 1999 survey of survey of “101 individuals or couples who cared for 132 colonies of free-roaming cats in north central Florida” illustrates the importance caregivers place on health:

“More than a third of the caretakers reported that they had provided some kind of veterinary care (not including being neutered at the TNR clinic) for the cats in the past or would provide veterinary care if it was necessary in the future. This type of care included booster vaccinations, parasite control, antibiotic treatment, ear medication, veterinary examinations, and emergency treatment.” [9]

In addition, 96% provided food, and 75% provided shelter. It’s important to note, too, that these numbers are conservative relative to the care received by the cats, in that (1) some caregivers were responsible for multiple cats, and (2) respondents to the survey were not necessarily the individuals who provided food, shelter, and so forth.

Such findings are certainly consistent with my own experience. The TNR networks I’m tapped into (mostly by way of e-mail or online bulletin boards) are typically buzzing with requests from, and recommendations to, caregivers committed to maintaining and improving the health of feral cat colonies.

On the other hand, it’s not clear from Dauphiné and Cooper’s paper that their reference to animal hoarding has anything to do with the behavior’s defining characteristics at all. More than anything else, the authors seem to be suggesting that resistance to TNR “alternatives” constitutes some psychiatric disorder—a possible reference to animal hoarders’ “reluctance to remove any animals, even when adequate homes were available.” [3]

Alternatives to TNR
Respectable sanctuaries, as I’ve already discussed, are few and far between, and typically at operating at capacity. In any case, such environments are not in the best interest of unsocialized cats. No-kill shelters, too, are scarce, and—recognizing realities Dauphiné and Cooper (and veterinarian Christine Storts, whose letter they cite) overlook or ignore—generally endorse TNR as their feral cat management approach. [10]

And as for “traditional animal control,” that’s nothing more than a rather cowardly euphemism for trap-and-kill.

What about the harassment and threats? Here, Dauphiné and Cooper cite Paul Barrows’ 2004 article “Professional, Ethical, and Legal Dilemmas of Trap-Neuter-Release,” and Pamela Jo Hatley’s 2004 paper, “Will Feral Cats Silence Spring in Your Town?” “During the past several years,” writes Barrows:

“as debate regarding abandoned and feral cats has become more heated, concerns have emerged regarding the extent to which some activists will go to promote their cause. Those supporting trap and removal of abandoned and feral cats, rather than TNR, have reported verbal abuse, personal threats, disruption of public forums, and interference with the conduction of their businesses.” [5]

Dauphiné and Cooper buy into Barrows’ account without bothering to check out his source (actually, these two make a shameful habit of such shortcuts throughout their paper, thereby raising questions about their numerous assertions, and, more problematically, their capabilities and integrity as researchers). In fact, Barrows cites a 2002 Wall Street Journal story in which exactly one of “those supporting trap and removal”—Frank Spiecker, of Garden State Pest Management—was interviewed:

“…property managers, fearing health complaints or lawsuits, hire Mr. Spiecker to trap and remove stray cats… Cat jobs have gotten him screamed at, threatened and jostled. His truck has been jumped on and pounded, his traps run over, and his trapped cats freed… To cat lovers, he abets feline mass murder, since most of the cats he traps end up dead.” [11]

All of which seems remarkably flimsy for describing and condemning—as Dauphiné and Cooper do—the behaviors of “many such people.” Until it’s compared to the even flimsier “evidence” provided by Hatley:

“Many citizens and public officials have voiced concerns about the public health issues and wildlife issues involved in hoarding large numbers of cats in the wild. Some who have resisted the extreme efforts by proponents of TNR and cat colonies have been subjected to verbal abuse and threats.” [6]

Dodgy research practices aside, the notion that one’s preference for TNR over “enclosed sanctuaries, no-kill shelters, and traditional animal control” is indicative of some psychiatric disorder remains a mighty hard sell. Dauphiné and Cooper’s so-called alternatives are simply not—in a very literal sense—viable options.

* * *

To compare TNR to animal hoarding betrays either a profound lack of knowledge about either one, or a desperate attempt to taint the former by association with the latter. I suspect that, like the most despicable political strategists, Jessup, Dauphiné and Cooper, and Lepczyk et al., threw it out there just to see if it would stick—the connection they’re attempting to make certainly has nothing to do with science.

I’ve a friend who jokes that the only thing feral cats aren’t being blamed for these days is climate change. Well, not yet, anyhow.

Literature Cited
1. Lepczyk, C.A., et al., “What Conservation Biologists Can Do to Counter Trap-Neuter-Return: Response to Longcore et al.” Conservation Biology. 2010. 24(2): p. 627-629.

2. Jessup, D.A., “The welfare of feral cats and wildlife.” Journal of the American Veterinary Medical Association. 2004. 225(9): p. 1377-1383.

3. Frost, R., “People Who Hoard Animals.” Psychiatric Times. 2000. 17(4).

4. Storts, C.M., “Discussion on TNR programs continue (letter).” Journal of the American Veterinary Medical Association. 2003. 222: p. 711–712.

5. Barrows, P.L., “Professional, ethical, and legal dilemmas of trap-neuter-release.” Journal of the American Veterinary Medical Association. 2004. 225(9): p. 1365-1369.

6. Hatley, P.J. (2004) Will Feral Cats Silence Spring in Your Town? www.pamelajohatley.com/Articles/ABA.pdf Accessed August 8, 2010.

7. Dauphiné, N. and Cooper, R.J., Impacts of Free-ranging Domestic Cats (Felis catus) on birds in the United States: A review of recent research with conservation and management recommendations, in Fourth International Partners in Flight Conference: Tundra to Tropics. 2009. p. 205–219.

8. Patronek, G.J., “Hoarding of animals: An under-recognized public health problem in a difficult-to-study population.” Public Health Reports. 1999. 114(1): p. 81–87.

9. Centonze, L.A. and Levy, J.K., “Characteristics of free-roaming cats and their caretakers.” Journal of the American Veterinary Medical Association. 2002. 220(11): p. 1627-1633.

10. Winograd, N.J., Redemption: The myth of pet overpopulation and the no kill revolution in America. 2007: Almaden Books.

11. Sterba, J.P., Tooth and Claw: Kill Kitty?, in Wall Street Journal. 2002: New York. p. A.1

The Work Speaks—Part 7: Leaky Sink

21 Jun 2010•Cats and Birds, Population Estimates, Research Protocol, Threats to Wildlife

In April, Conservation Biology published a comment authored by Christopher A. Lepczyk, Nico Dauphiné, David M. Bird, Sheila Conant, Robert J. Cooper, David C. Duffy, Pamela Jo Hatley, Peter P. Marra, Elizabeth Stone, and Stanley A. Temple. In it, the authors “applaud the recent essay by Longcore et al. (2009) in raising the awareness about trap-neuter-return (TNR) to the conservation community,” [1] and puzzle at the lack of TNR opposition among the larger scientific community:

“…it may be that conservation biologists and wildlife ecologists believe the issue of feral cats has already been studied enough and that the work speaks for itself, suggesting that no further research is needed.”

In fact, “the work”—taken as a whole—is neither as rigorous nor as conclusive as Lepczyk et al. suggest. And far too much of it is plagued by exaggeration, misrepresentations, errors, and obvious bias. In Part 6 of this series, I critiqued Christopher Lepczyk’s paper Landowners and cat predation across rural-to-urban landscapes, published in 2003. Here, I’m going to examine two studies conducted by Philip J. Baker and various collaborators.

The Studies
In the first study, Baker et al. distributed questionnaires to 3,494 households across a 4.2 km² area of northwest Bristol (UK), and used responses to estimate cat ownership and predation levels (via prey returned home). [2] This work served as a pilot study for the subsequent study.

The second study, conducted August 2005–July 2006, was also conducted in Bristol. Added to the original 4.2 km² site were nine 1 km² sites. The researchers used very similar sampling methods, but, based on results of their pilot study, had somewhat more specific objectives:

To quantify cat density
To quantify the various species of birds killed by cats.
To estimate the impact of cat predation by species and site.
To determine whether the predation observed was compensatory or additive. [3]

Sources and Sinks
Among the authors’ conclusions from the pilot study was that, at least for three of the ten bird species surveyed:

“…it is possible that cat predation was significantly affecting levels of recruitment and creating a dispersal sink for more productive neighboring areas.” [2]

Dispersal sinks or habitat sinks, are patches of low-quality habitat that are unable to sustain a population of a particular species were it not for immigration from higher quality habitat patches—called sources—nearby. So, what Baker et al. are suggesting is that predation by cats may be extensive enough to deplete populations of certain bird species at their study site, such that at least some of the birds observed there were immigrants from nearby habitat.

But the authors also point out that, “despite occurring at very high densities, the summed effects on prey populations appeared unlikely to affect population size for the majority of prey species.” [2] And even for House sparrows, which were among the three species of concern (and, apparently, in decline throughout the UK’s urban areas), Baker et al. note that their “numbers appear to be stable in Bristol as a whole.”

So, is the area a habitat sink or not?

A cursory look at the theory and empirical measurement of source-sink dynamics reveals great complexity. Variations across time and geography must be taken into account—the ebb and flow of local populations might easily be overlooked or misunderstood by applying a short time horizon (i.e., 12 months) and arbitrary boundaries (i.e., those that define the study site). Annual rainfall, for example, can dramatically influence yearly population levels on a local scale. And it’s been shown that source-sink dynamics can occur over distances of 60–80 km. [4] In fact, the determination of sinks and sources in the field can be problematic enough that sources sometimes appear to be sinks and vice-versa. [5]

Given the complex nature of source-sink dynamics, the suggestion by Baker et al. that cat predation may be creating a habitat sink seems rather premature. Such assertions—despite the requisite disclaimers (the authors note only that “it is possible”)—tend to attract attention and gain traction. Longcore et al., for example, cited the pilot study in their 2009 essay, “Critical Assessment of Claims Regarding Management of Feral Cats by Trap-Neuter-Return.” [6]

Of greater interest to me, though, are the assumptions Baker et al. used to estimate the impact of cat predation.

Counting Cats and Counting Birds
In both studies, the authors quantified the impact of cat predation on bird populations by comparing different levels of predation with different bird densities. Their maximum impacts, for example, assumed that all cats were hunters—despite the fact that 51–74% of the cats included in the two studies brought home no prey at all—and that bird productivity was zero (i.e., no young birds survive to adulthood). As the authors admit:

“This was clearly not realistic, as the estimated maximum numbers of birds killed typically exceeded breeding density and productivity combined, such that the prey populations studied would probably have gone extinct rapidly at a local level or acted as a major sink for birds immigrating from neighbouring areas.” [3]

But how realistic are their other estimates?

A detailed examination of a single species at a one site (taken from the second study, for which such information is available) illustrates some flaws. I looked at House sparrows for the 1 km² site designated as ST5277. Here, 18 participants reported that their 22 cats returned a total of 30 prey items, nine of which were birds (two of them “unidentified”). Of the birds returned home, two were House sparrows.

When it comes to estimating impacts, though, Baker et al. use figures of 332–1,245 House sparrows killed by the cats of ST5277. The maximum, we already know, is “not realistic,” but even the minimum seems awfully high. So, where are these birds coming from?

To start with, two adjustments have to be made to the original predation figure. First, the two unidentified birds are “distributed” across the categories of bird species that were identified. Then, we have to account for participant drop-out; not all of the 22 cats were surveyed for the entire year of the study. Now we’re up to an average of 8.7 House sparrows brought home annually by the cats at this site.

But of course there are more than 22 cats at ST5277. Baker et al. estimate that there are 314 of them (although we know very little about the factors that affect their hunting ability and success—for example, their access to the outdoors, age, etc.). We also know that only seven of the 22 cats included in the study brought home prey. In other words, 32% of the cats surveyed were documented hunters. Based on these numbers, then, we can estimate the yearly predation rate of House sparrows at ST5277 to be roughly 125—well short of the minimum proposed by Baker et al. (and just a quarter of their intermediate rate).

There are some minor differences between their method for estimating predation rates and mine. For the most part, though, the “missing” sparrows can be found in the authors’ use of a correction factor (3.3) proposed by Kays and DeWan to account for prey killed but not returned home. [7] Undoubtedly, cats fail to bring home all the prey they catch (though they also undoubtedly bring home prey they didn’t kill), but there is good reason to doubt Kays and DeWan’s “correction.” Among the flaws in their analysis were small, dissimilar samples of cats, and a failure to account for highly skewed data sets.

So, even setting aside the complexities of source-sink dynamics, these inflated predation rates, combined with the fact that “the estimates of breeding density presented in this manuscript should be regarded as minima,” [3] raise serious doubts about whether the site is in fact a habitat sink (or, if so, to what extent).

Compensatory and Additive Predation
As I’ve discussed previously, even accurately predicted levels of predation can be deceptive. There’s compensatory predation (in which prey would have died even in the absence of a particular predator, due to illness, starvation, other predators, etc.) and additive predation (in which healthy prey are killed). It’s the difference between, as Beckerman et al. put it, the “doomed surplus hypothesis” and the “hapless survivor hypothesis.” [8]

When it comes to relating predation to population levels, it’s critical to understand the difference, and know the extent to which each type is occurring.

To get at this critical issue, Baker et al. compared the physical attributes (e.g., muscle mass score, mean fat score, etc.) of 86 birds killed by collisions (e.g., with cars, windows, etc.) to those of 48 birds killed by cats. Although the authors point out, “the relationship between body mass and quality (i.e., likelihood of long-term survival and therefore reproductive potential) in passerines is complex,” they nevertheless conclude that the birds killed by cats “were likely to have had poor long-term survival prospects.” [3] (An earlier study comparing spleen mass arrived at essentially the same conclusion: that birds killed by cats “often have a poor health status.” [9])

Still, Baker et al. express caution about their findings:

“The distinction between compensatory and additive mortality does, however, become increasingly redundant as the number of birds killed in a given area increases: where large numbers of prey are killed, predators would probably be killing a combination of individuals with poor and good long-term survival chances. The predation rates estimated in this study would suggest that this was likely to have been the case for some species on some sites.”

But their inflated predation rates and low estimates of breeding density combine to diminish the apparent level of compensatory predation. Were these estimates adjusted to better reflect the conditions at the site, the “redundancy” the authors refer to would be reduced considerably.

* * *

It’s not clear why Longcore et al. cited the pilot study their essay, but left out any mention of the much larger subsequent study. Perhaps it was just a matter of timing—“Cats About Town” was published in August of 2008, while “Critical Assessment” was published in August of 2009. A year is not much time in the world of scientific journals, and it’s possible that the two manuscripts more or less crossed in the mail. On the other hand, the pilot study fits more neatly into the argument put forward by Longcore et al.—an argument that doesn’t even recognize the distinction between compensatory and additive predation.

Of course, Baker et al. did themselves no favors, either. By using inflated predation rates—the result of some peculiar, unjustified assumptions—they virtually buried the most important findings of their study.

References
1. Lepczyk, C.A., Mertig, A.G., and Liu, J., “Landowners and cat predation across rural-to-urban landscapes.” Biological Conservation. 2003. 115(2): p. 191-201.

2. Baker, P.J., et al., “Impact of predation by domestic cats Felis catus in an urban area.” Mammal Review. 2005. 35(3/4): p. 302-312.

3. Baker, P.J., et al., “Cats about town: is predation by free-ranging pet cats Felis catus likely to affect urban bird populations?“ Ibis. 2008. 150: p. 86-99.

4. Tittler, R., Fahrig, L., and Villard, M.-A., “Evidence of Large-Scale Source-Sink Dynamics and Long-Distance Dispersal among Wood Thrush Populations.” Ecology. 2006. 87(12): p. 3029-3036.

5. Runge, J.P., Runge, M.C., and Nichols, J.D., “The Role of Local Populations within a Landscape Context: Defining and Classifying Sources and Sinks.” The American Naturalist. 2006. 167(6): p. 925-938.

6. Longcore, T., Rich, C., and Sullivan, L.M., “Critical Assessment of Claims Regarding Management of Feral Cats by Trap–Neuter–Return.” Conservation Biology. 2009. 23(4): p. 887–894.

7. Kays, R.W. and DeWan, A.A., “Ecological impact of inside/outside house cats around a suburban nature preserve.” Animal Conservation. 2004. 7(3): p. 273-283.

8. Beckerman, A.P., Boots, M., and Gaston, K.J., “Urban bird declines and the fear of cats.” Animal Conservation. 2007. 10(3): p. 320-325.

9. Møller, A.P. and Erritzøe, J., “Predation against birds with low immunocompetence.” Oecologia. 2000. 122(4): p. 500-504.

The Work Speaks—Part 6: Pain by Numbers

14 Jun 2010•Cats and Birds, Population Estimates, Research Protocol, The Cat Debate, Threats to Wildlife

“…it may be that conservation biologists and wildlife ecologists believe the issue of feral cats has already been studied enough and that the work speaks for itself, suggesting that no further research is needed.”

In fact, “the work”—taken as a whole—is neither as rigorous nor as conclusive as Lepczyk et al. suggest. And far too much of it is plagued by exaggeration, misrepresentations, errors, and obvious bias. In Part 5 of this series, I critiqued Cole Hawkins’ 1998 PhD dissertation. Here, I’m going to untangle some of Lepczyk’s own PhD work: Landowners and cat predation across rural-to-urban landscapes, published in 2003.

The Study
In this study, surveys were distributed across three southeastern Michigan landscapes (rural, suburban, and urban) corresponding to established breeding bird survey (BBS) routes. [2] Among the survey questions:

“If you or members of your household own cats that are allowed access to the outside, approximately how many dead or injured birds a week do all the cats bring in during the spring and summer months (April through August) (0, 1, 2–3, 4–5, 6–7, 8–9, 10–15, 16–20, more than 20)?”

Based on 968 surveys returned from 1654 private landowners (a decent response rate of 58.5%), Lepczyk et al. conclude:

“Across the three landscapes there were ~800 to ~3100 cats, which kill between ~16,000 and ~47,000 birds during the breeding season, resulting in a minimum of ~1 bird killed/km/day.”

Increasing Uncertainty
How do Lepczyk and his collaborators arrive at these figures? It’s not entirely clear, actually. Despite numerous attempts, I’ve been unable to follow all of their calculations. However, using their data, I developed my own estimate: 1,119 outdoor cats, 511 of which were reported to be successful hunters.

Using this figure, I then summed across all three landscapes the birds killed or injured, plus those killed or injured by non-respondents’ hunting cats (based on the ratio of hunters to outdoor cats owned by respondents, or about 50%). The resulting estimate is 15,856 birds killed over the 22-week breeding season—close to the low estimate suggested by Lepczyk et al., but just a third of their maximum.

So, why the discrepancy?

One reason is that, at least for some of their estimates, Lepczyk et al. assumed that every landowner who didn’t respond to the survey owned outdoor cats. This, despite their survey results, which indicated that only about one-third of landowners fell into this category.

But the authors go further, generating predation estimates based on pure speculation, specifically that “non-respondents have 150% the number of outdoor cats as respondents.” [2] It should be noted that Lepczyk et al. also ran another scenario in which non-respondents had half the outdoor cats as did respondents—but, again, in both cases they assume that every non-respondent owned outdoor cats.

As a result of this approach, the authors end up in some strange territory: the estimated number of cats owned by non-respondents (based on the assumptions described above) far exceeds the number owned by respondents—by more than a two-to-one margin, in some cases. If the greatest impacts are going to be attributable to non-respondents, then what’s the point of doing the survey in the first place? There are accepted methods by which one can manage uncertainty—statistical analysis, confidence intervals, and the like. What Lepczyk et al. have done serves just one purpose: to inflate apparent predation rates.

Skewed Distributions
In addition to the flaws described above, there are some fundamental errors in the way the authors handle their data. Like so many others, Lepczyk et al. ignore the fact that their data is not normally distributed:

Lepczyk et al. use the average number of birds killed/cat to calculate the total number of bids killed for each of the three landscapes. As I discussed previously), this is a highly positively skewed distribution—using a simple average, therefore, greatly overestimates the cats’ impact (by as much as a factor of two).
A similar error is made when the authors use an average to describe the number of outdoor cats owned by each landowner. Again, because this is a skewed distribution, their use of a simple average exaggerates the extent of predation.
The two inflated figures described in (1) and (2) are multiplied together, further inflating estimated predation rates.

Barratt has suggested that “median numbers of prey estimated or observed to be caught per year are approximately half the mean values, and are a better representation of the average predation by house cats based on these data.” [3] Accounting for the first point alone, then, my estimate is reduced to 8,000 birds killed over the 22-week breeding season.

Accounting for the second point is somewhat trickier. For one thing, we don’t know what constitutes an outdoor cat here—the survey simply asked respondents if they owned cats “that are allowed access to the outdoors.” [2] However, we do know the results of a 2003 survey, which indicated that nearly half of the cats with outdoor access were outside for two or fewer hours a day. And 29% were outdoors for less than an hour each day. [4] Although these figures almost certainly reflect owners in urban and suburban landscapes more than those in rural landscapes, it’s clear that a simple yes-or-no question on the subject is insufficient. Indeed, such a question will invariably overestimate the number of “outdoor cats”—which in turn overestimates predation rates.

This, coupled with the error inherent in using a simple average, pushes predation estimates lower. And the third point reduces those estimates further still. Taken together, these corrections could put my estimate closer to 4,000 birds. More important, the upper estimate proposed by Lepczyk et al.—47,000 birds—could easily be 10 times too high.

The Small Print
Despite their inflated figures, Lepczyk et al. suggest—rather absurdly, in light of the substantial flaws described above—that perhaps their estimates are actually too conservative:

“One caveat to our study is that landowners may have underestimated the number of cats they allow access to the outside. Such a result was found in a similar study of landowners in Wisconsin (Coleman and Temple, 1993).” [1] (Note: After reviewing “Rural Residents’ Free-Ranging Domestic Cats: A Survey,” [5] I’ve found no evidence of such a result.)

“… we found that a very common volunteered response among landowners that had no outdoor cats was that either their neighbors owned outdoor cats or that feral cats were present in the vicinity of their land… [suggesting] that at least some landowners under reported or chose not to report the number of outdoor cats they owned.”

But what about their reports of birds brought home killed or injured—how trustworthy were those? After all, the survey (mailed during the first week of October) asked respondents to recall the number of birds their cat(s) brought home April through August. Surely, there was a lot of guesswork involved. In fact, David Barratt found this kind of guesswork to overestimate predation rates. In a study published five years prior to “Landowners and Cat Predation,” Barratt concluded, “predicted rates of predation greater than about ten prey per year generally over-estimated predation observed.” [3]

The two studies cannot be compared directly for a number of reasons, but by way of comparison, the average predation rate used by Lepczyk et al. is approximately 31 birds/cat for the 22-week breeding season. Using Barratt’s work, in which the “heaviest” six continuous months correspond to about 58% of yearly prey totals, [6] I converted this to a yearly rate of 53 birds/cat/year. Barratt has shown that the actual predation rate, at this level, is less than half the rate predicted by cat owners. In other words, predictions of 50 birds/year generally correspond to catches closer to 25 birds/year.

While Lepczyk et al. emphasize the potential for under-estimating predation levels, they never consider the risk of over-estimating these levels—or their most obvious potential source of error: landowners’ recollections of birds killed. The authors question respondents’ reports of outdoor cats, but accept without question their reports of birds injured or killed over the previous six-month period. And, as Barratt indicated, such reports can be inflated by a factor of two or more!

Something else I find troubling comes, of all places, from the Acknowledgements section. Among those thanked “for helpful and constructive reviews” are American Bird Conservancy (ABC) president George Fenwick and Linda Winter, director of ABC’s Cats Indoors! campaign. It’s not clear how Fenwick and Winter contributed to the final paper, but their involvement on any level raises questions about possible bias. Certainly, Winter has credibility issues when it comes to “research” about the impact of free-roaming cats on birds, as I’ve already described (see also pp. 18–24 of TNR Past present and future: A history of the trap-neuter-return movement [7]).

* * *

The same year Lepczyk’s paper was published, the American Veterinary Medicine Association held an Animal Welfare Forum “devoted to the management of abandoned and feral cats.” [8] In attendance were more than 200 veterinarians, animal control officials, wildlife conservationists, and animal advocates—each with a different perspective on feral cats in general and TNR in particular.

In welcoming this diverse group, then-President-Elect Bonnie Beaver recognized the range of contentious issues before them:

“Feral cats evoke hot debates about ecological issues, individual cat welfare, human responsibilities, intercat disease transmission, humaneness, zoonosis control, and management and dissolution of unowned cats.” [8]

Amidst the “hot debate,” though, Beaver was optimistic:

“We will not always agree, but we will come away with increased knowledge and a renewed commitment to work for the welfare of all the animals with which we share the earth” [8]

While I tend to share Beaver’s optimism, I think the debate is hurt—if not derailed entirely—by the publication of research aimed not at increasing our collective knowledge, but rather at supporting a particular position. Like Cole Hawkins’ dissertation, “Landowners and Cat Predation” is, at best, an interesting pilot study for subsequent work. And yet, it’s widely—and uncritically—cited in the feral cat/TNR literature. Longcore et al., for example, refer to it as “evidence [indicating] that cats can play an important role in fluctuations of bird populations,” [9] despite the fact that Lepczyk et al. don’t actually address the issue of bird populations at all. More recently, Dauphiné and Cooper use the inflated predation rate suggested by Lepczyk et al. (along with rates proposed by other researchers) to arrive at their “billion birds” figure. [10]

The method employed in “Landowners and Cat Predation”—asking owners of cats to recall the number and species of birds over the previous six-month period—invites overestimation from the very outset. Lepczyk et al. then inflate these numbers through both careless (e.g., using averages to describe skewed data) and deliberate (e.g., assuming all non-respondents owned cats—perhaps 50% more than respondents did) means. Rather than getting us any closer to the truth about cat predation, this study only obscured it further.

Worse, it’s been packaged and sold—and subsequently “bought”—as rigorous science, thereby giving it an undeserved legitimacy. Such efforts are impediments to knowledge and understanding—and therefore, to progress.

References
1. Lepczyk, C.A., et al., “What Conservation Biologists Can Do to Counter Trap-Neuter-Return: Response to Longcore et al.” Conservation Biology. 2010. 24(2): p. 627-629.

2. Lepczyk, C.A., Mertig, A.G., and Liu, J., “Landowners and cat predation across rural-to-urban landscapes.” Biological Conservation. 2003. 115(2): p. 191-201.

3. Barratt, D.G., “Predation by house cats, Felis catus (L.), in Canberra, Australia. II. Factors affecting the amount of prey caught and estimates of the impact on wildlife.” Wildlife Research. 1998. 25(5): p. 475–487.

4. Clancy, E.A., Moore, A.S., and Bertone, E.R., “Evaluation of cat and owner characteristics and their relationships to outdoor access of owned cats.” Journal of the American Veterinary Medical Association. 2003. 222(11): p. 1541-1545.

5. Coleman, J.S. and Temple, S.A., “Rural Residents’ Free-Ranging Domestic Cats: A Survey.” Wildlife Society Bulletin. 1993. 21(4): p. 381–390.

6. Barratt, D.G., “Predation by House Cats, Felis catus (L.), in Canberra, Australia. I. Prey Composition and Preference.” Wildlife Research. 1997. 24(3): p. 263–277.

7. Berkeley, E.P., TNR Past present and future: A history of the trap-neuter-return movement. 2004, Bethesda, MD: Alley Cat Allies.

8. Kuehn, B.M. and Kahler, S.C. The Cat Debate. JAVMA Online 2004 November 27, 2009 [accessed 2009 December 24]. http://www.avma.org/onlnews/javma/jan04/040115a.asp.

9. Longcore, T., Rich, C., and Sullivan, L.M., “Critical Assessment of Claims Regarding Management of Feral Cats by Trap–Neuter–Return.” Conservation Biology. 2009. 23(4): p. 887–894.

10. Dauphiné, N. and Cooper, R.J., Impacts of Free-ranging Domestic Cats (Felis catus) on birds in the United States: A review of recent research with conservation and management recommendations, in Fourth International Partners in Flight Conference: Tundra to Tropics. 2010. p. 205–219.

The Work Speaks—Part 5: Jumping to Conclusions

11 Jun 2010•Cats and Birds, Research Protocol, Threats to Wildlife

“…it may be that conservation biologists and wildlife ecologists believe the issue of feral cats has already been studied enough and that the work speaks for itself, suggesting that no further research is needed.”

In fact, “the work”—taken as a whole—is neither as rigorous nor as conclusive as Lepczyk et al. suggest. And far too much of it is plagued by exaggeration, misrepresentations, errors, and obvious bias. In Part 4 of this series, I discussed how feral cat/TNR researchers often misuse averages to characterize skewed distributions, and how that error overestimates the impact of free-roaming cats on wildlife.

For the next few posts, I’m going to critique three of the studies most often cited by these researchers, starting with Cole Hawkins’ 1998 PhD dissertation, Impact of a subsidized exotic predator on native biota: Effect of house cats (Felis catus) on California birds and rodents. I mentioned Hawkins’ dissertation previously, but only briefly. Here, I’ll take a closer look, paying particular attention to how he gets from his results to his rather dubious conclusions.

The Study
Hawkins’ two-year study was conducted in Alameda County, CA, spread across two adjacent parks. He started by designating a “cat area” (where, nearby, free-roaming cats were being fed) and a “no-cat area” (where no cats were being fed), and then designated “rodent grids” (nine locations used for trapping and counting rodents) and walking transects (from which bird surveys were conducted) in each area. Hawkins then compared the number of birds and rodents detected in the two areas.

Among Hawkins’ conclusions:

“The differences observed in this study were the results of the cat’s predatory behavior.” [2] (It should be noted that Hawkins tempered this assertion in his 1999 article summarizing the work: “The differences observed in this study may have been due to the cats’ predatory behavior.” [3] (italics mine))

And this:

“The presence of cats in this study area already has caused a shift in the composition of the rodent community; it is possible that a shift in the larger biotic community could follow.”

And, finally:

“It is not prudent to manage for wildlife and allow cat feeding in the same parks.”

Unfair Comparisons
But Hawkins’ findings are insufficient to supports such claims; indeed, his methodology doesn’t allow for them. Hawkins has no idea what the cat area was like prior to his arrival; he merely assumes the populations of birds and rodents would have been identical to those found at the no-cat area, and makes his comparisons accordingly. In fact, there are a number of factors that indicate that the two areas are not as comparable as Hawkins suggests:

The cat area was almost a peninsula, with a lake on one side and a residential area (within 0.5 km) on the other. The no-cat area, on the other hand, was located largely in the interior of the parks.
Hawkins notes that there were more people in the cat area (often twice as many as were observed at the no-cat area), but dismisses the possibility that their presence may have influenced the numbers of birds and rodents he observed there.
The habitat along the 2.2 km transects from which bird counts were conducted varied considerably between the two areas. Compared to the no-cat area, the cat area had 31% less chaparral, 183% more trees, 52% less grass, and 240% more “modified” habitat (it’s not clear what Hawkins means by “modified,” but I assume it refers to habitat that reflects significant human impact).
Finally, the presence of pesticides may have played a role. According to a 2002 report (the earliest I was able to find) from the East Bay Regional Park District, “The focus of Lake Chabot’s weed control efforts are vegetation reduction within the two-acre overflow parking lot, picnic sites and firebreaks around park buildings, corp. yard, service yard, and the Lake Chabot classroom.” [4] And it’s clear from Hawkins’ 1999 article that the cat area did include picnic sites: “…over half of the cat scat in this study was collected under and around picnic tables.” [3] Now, Hawkins’ fieldwork was done in 1995 and 1996, but if there was any pesticide use during the study period, it may have affected the results—especially if the pesticide was distributed differently across the two areas.

Cats and Birds
“Almost twice as many birds were seen on the no-cat transect as on the cat transect,” writes Hawkins. But it’s not quite as simple as that—the details reveal a rather complex, often uneven count over the course of the study. Nevertheless—and despite the differences between the two areas—Hawkins’ only explanation is the cats. This is especially true for ground-feeders:

The preference of ground feeding birds for the no-cat treatment was striking; for example, California quail were seen almost daily in the no-cat area, whereas they were never seen in the cat area.

What’s more striking to me is the fact that five of the nine ground-feeding species included in the study showed no preference for either area. But Hawkins scarcely acknowledges the point, and doesn’t even hint at an explanation. “Birds that were known to nest on or near the ground or in shrubs and vines ≤ 1.5 m in height” also showed no preference between the two areas (though no nest counts were conducted).

The picture painted by Hawkins is that bird species absent from the cat area represent species killed off by the cats. But it’s generally accepted that cats are opportunistic hunters, catching whatever prey is readily available and easily caught. [5–8] Fitzgerald and Turner, for example, argue that “domestic cats (both house and feral ones) are best described as generalist resident predators, exploiting a wide range of prey, and able to switch readily from one prey to another.” [9] So, how is it that some species were present at the cat site while others were not? Again, Hawkins offers no explanation.

In fact, it’s clear from Hawkins’ study that the cats aren’t much of threat at all to the birds—even vulnerable ground-feeding and ground-nesting species—in the cat area. Of the 120 scat samples found by searching the cat area, “65% were found to contain rodent hair and 4% feathers.” [2] This finding comes toward the end of the study, when the cat population was at its greatest—and still, only 4% contained feathers. And this could easily represent one cat and one bird.

One final point about the birds: Hawkins suggests (without explanation) that the olive-sided flycatcher, American robin, and Stellar’s jay—all of which showed no preference for either the no-cat area or the cat area—may have been responding to a “specialized habitat.” Could it be that the birds not seen in the cat area were also responding to a specialized habitat—by “migrating” to a place with less human activity (e.g., the no-cat area), for example? Once again, Hawkins has no comment.

Cats and Rodents
The fact that scats indicated rodents were predated to a greater extent than birds is hardly surprising [5, 6, 9, 10], but it should be noted the 65% figure represents the frequency of occurrence, and not a predation rate (a topic I address in greater detail here).

Hawkins’ analysis didn’t reveal whether the rodent hair was that of deer mice, harvest mice (both of which were found less often in the cat area than in the no-cat area), house mice (found more often in the cat area), or California voles (which showed no preference for either area). In any case, it’s not clear that the cats were responsible for the presence or absence of any of these rodent species. Again, the selective dietary habits suggested by Hawkins simply don’t fit with the domestic cat’s profile as a “generalist resident predator.”

Two additional points that might explain the differences Hawkins observed concern the habitat of the cat area. First, there’s the nearby lake and residences—potential sources of pollution that could affect nearby plant and animal life. Secondly, there’s the issue of possible pesticide use mentioned previously. As I say, it’s largely conjecture on my part; at the same time, though, it’s easy to imagine its potential impact on small mammals (and ground-feeding birds, for that matter).

Finally, Hawkins suggests that certain bird species were responding to specialized habitat—perhaps the rodents were simply doing the same.

Cats
Hawkins used track plates (baited devices that detect the presence of mammals by way of preserved “footprints”) for “estimating a relative cat presence index,” but found only one cat track in 200 track plate nights. And, “in 560 days of exposure, no scat was found in any of the sand boxes.” [2] Now, the cats were seen at feeding stations and on the rodent grids of the cat area—as many as 26 during a one-week period toward the end of the study. But clearly, they were not where Hawkins was expecting them to be. If, after two years at the study site, Hawkins was unable to get a better handle on the presence of the cats, how can he be so sure of their behavior when it comes to predation?

If, as Hawkins argues, the differences observed between the two areas are a result of the cats’ predatory behavior, then one would expect the number of birds and rodents to decrease as the number of cats increases. Yet, Hawkins’ findings don’t bear this out.

And then there are the unanswered questions about the cats—for example:

Where did these cats come from—were they illegally dumped, the result of nearby residents’ unsterilized cats breeding? Did they belong to the residents?
Were the cats sterilized? (Their increasing numbers would suggest that they weren’t.)
Were these cats part of a managed TNR colony? (Local newspaper reports indicate a long-standing battle between TNR advocates and opponents. [11–13])

Considering the central role these cats played in Hawkins’ two-year study, he knew surprisingly little about their behavior—including various factors that surely had an impact on his findings.

* * *

In their recent comment, Lepczyk et al. suggest that conservation biologists and wildlife ecologists “look to the evolutionary biology community” [1] for an example of how to influence policy. For feral cat/TNR opponents interested in shaping policy, it seems Hawkins’ study has become quite popular. [14–17] Actually, Nico Dauphiné and Robert J. Cooper take its already-tenuous claims one step further, citing Hawkins’ work (actually a 2004 conference paper that summarizes his dissertation [18]) as evidence that “the continuous predation pressure exerted by exotic predators in exponentially high densities can and has resulted in numerous local extinctions of continental land birds.” [8]

But is Hawkins’ methodology one that evolutionary biologists would advocate—or even recognize? Not likely.

Hawkins draws conclusions—infers important causal relationships—without any evidence of what “pre-treatment” conditions were like. And ignores entirely his own findings when they contradict his conclusions. Rather than beginning his inquiry with questions to answer, it seems Hawkins had his answer from the outset. At best, his work is an interesting pilot study—generating research questions for a more rigorous, less biased investigation.

References
1. Lepczyk, C.A., et al., “What Conservation Biologists Can Do to Counter Trap-Neuter-Return: Response to Longcore et al.” Conservation Biology. 2010. 24(2): p. 627-629.

2. Hawkins, C.C., Impact of a subsidized exotic predator on native biota: Effect of house cats (Felis catus) on California birds and rodents. 1998, Texas A&M University.

3. Hawkins, C.C., Grant, W.E., and Longnecker, M.T., “Effects of Subsidized House Cats on California Birds and Rodents.” Transactions of the Western Section of the Wildlife Society. 1999. 35: p. 29–33.

4. Brownfield, N.T., 2002 Annual Analysis of Pesticide Use East Bay Regional Park District. 2003, East Bay Regional Park District. www.ebparks.org/files/stew_pest_report_02.pdf

5. Barratt, D.G., “Predation by house cats, Felis catus (L.), in Canberra, Australia. II. Factors affecting the amount of prey caught and estimates of the impact on wildlife.” Wildlife Research. 1998. 25(5): p. 475–487.

6. Fitzgerald, B.M., Diet of domestic cats and their impact on prey populations, in The Domestic cat: The biology of its behaviour, D.C. Turner and P.P.G. Bateson, Editors. 1988, Cambridge University Press: Cambridge; New York. p. 123–147.

7. Lepczyk, C.A., Mertig, A.G., and Liu, J., “Landowners and cat predation across rural-to-urban landscapes.” Biological Conservation. 2003. 115(2): p. 191-201.

8. Dauphiné, N. and Cooper, R.J., Impacts of Free-ranging Domestic Cats (Felis catus) on birds in the United States: A review of recent research with conservation and management recommendations, in Fourth International Partners in Flight Conference: Tundra to Tropics. 2010. p. 205–219.

9. Fitzgerald, B.M. and Turner, D.C., Hunting Behaviour of domestic cats and their impact on prey populations, in The Domestic Cat: The biology of its behaviour, D.C. Turner and P.P.G. Bateson, Editors. 2000, Cambridge University Press: Cambridge, U.K.; New York. p. 151–175.

10. Woods, M., McDonald, R.A., and Harris, S., “Predation of wildlife by domestic cats Felis catus in Great Britain.” Mammal Review. 2003. 33(2): p. 174-188.

11. Chui, G., Stray Cats Live Harsh Lives in Area Parks, in San Jose Mercury News. 1985. p. 1

12. Bogue, G., Those Poor Cats Need a Human Assist, in Contra Costa Times. 1997: Walnut Creek, CA. p. A02

13. n.a., Spring controversy: What to do with feral cats?, in San Mateo Daily Journal, The (CA). 2001.

14. Longcore, T., Rich, C., and Sullivan, L.M., “Critical Assessment of Claims Regarding Management of Feral Cats by Trap–Neuter–Return.” Conservation Biology. 2009. 23(4): p. 887–894.

15. ABC, Domestic Cat Predation on Birds and Other Wildlife. n.d., American Bird Conservancy: The Plains, VA. www.abcbirds.org/abcprograms/policy/cats/materials/predation.pdf

16. Winter, L. and Wallace, G.E., Impacts of Feral and Free-Ranging Cats on Bird Species of Conservation Concern, G.E. Wallace, Editor. 2006, American Bird Conservancy. www.abcbirds.org/newsandreports/NFWF.pdf

17. Ash, S.J. and Adams, C.E., “Public Preferences for Free-Ranging Domestic Cat (Felis catus) Management Options.” Wildlife Society Bulletin. 2003. 31(2): p. 334–339.

18. Hawkins, C.C., Grant, W.E., and Longnecker, M.T. Effect of house cats, being fed in parks, on California birds and rodents. in Proceedings Of The 4th International Symposium On Urban Wildlife Conservation. 2004. Tucson, AZ: University of Arizona. http://cals.arizona.edu/pubs/adjunct/snr0704/snr07042l.pdf

The Work Speaks—Part 4: Mean Spirited

4 Jun 2010•Population Estimates, Research Protocol, Threats to Wildlife

“…it may be that conservation biologists and wildlife ecologists believe the issue of feral cats has already been studied enough and that the work speaks for itself, suggesting that no further research is needed.”

In fact, “the work”—taken as a whole—is neither as rigorous nor as conclusive as Lepczyk et al. suggest. And far too much of it is plagued by exaggeration, misrepresentations, errors, and obvious bias. In Part 3 of this series, I discussed the distinction between compensatory and additive predation. Here, I’ll focus on how feral cat/TNR researchers often misuse averages to characterize skewed distributions, and how that error overestimates the impact of free-roaming cats on wildlife.

Something’s Askew
When a data set is skewed, it is inappropriate to use the mean, or average, as a measure of central tendency. The mean should be used only when the data set can be considered normal—the familiar bell curve. As Woods et al put it:

“the simple average number of animals brought home is not a useful measure of central tendency because of the skewed frequency distribution of the numbers of prey items brought home…” [2]

Studies of cat predation routinely reveal a positively skewed distribution; a few cats are responsible for many kills, while many of the cats kill few, if any, prey. So when researchers use the mean to calculate the total number of prey killed by cats in a particular area, they overestimate the cats’ impact.

How common is this? Very [see, for example, 3-9]. Of the many cat predation studies I’ve read, only a few [2, 10, 11] properly account for the skewed nature of this distribution. And others [12-17] often take these inflated figures at face value—as evidence of the impact cats have on wildlife. Published repeatedly, the erroneous estimates take on an undeserved legitimacy.

The proper method for handling skewed distributions involves data transformations, the details of which I won’t go into here. The important point is this: in the case of a positively skewed distribution, the back-transformed mean will always be less than the simple mean of the same data set.

Big Deal
Depending on the particular distribution, the difference between the simple mean and the back-transformed mean can be considerable. Let’s use the 2003 study by Woods et al. [2] to illustrate. In the case of mammals killed and returned home by pet cats, the back-transformed mean was 28.3% less than the simple mean. Or, put another way, the simple mean would have overestimated the number of mammals killed by 39.5%. Similarly, when all prey items were totaled (as depicted in the illustration above), the simple mean would have overestimated the total number off all prey (mammals, birds, herpetofauna, and “others”) by 46.9%.

On the other hand, the figures for birds appear to break the rule mentioned above. In this case, the back-transformed mean (4.1) is actually a bit higher than the simple mean (4.0). How can this be? In order to log-transform the data set, Woods et al. had to first eliminate all the instances where cats returned home no prey—you can’t take the logarithm of 0. So, they were actually working with two data sets. Now, the second data set—which includes only those cats that returned at least one prey item—is also highly positively skewed. As a point of reference, its simple mean was approximately 5.6 birds/cat, which, compared to the back-transformed mean, is an overestimation of 37.5%.

By now, it should be apparent that log-transformed means have another important advantage over simple means: because you have to eliminate those zeros from the data set, you are forced to focus only on the cats that returned prey home—which, of course, is the whole point of such studies! And in the case of this study, Woods et al. found that 20–30% of cats brought home either no birds or no mammals. And 8.6% of the cats brought home no prey at all over the course of the study.

Transforming a data set (and then back-transforming its mean) is simpler than it sounds, but Barratt offers a useful alternative, rule-of-thumb method (one echoed by Fitzgerald and Turner [18]):

“…median numbers of prey estimated or observed to be caught per year are approximately half the mean values, and are a better representation of the average predation by house cats based on these data.” [10]

So, whereas Dauphiné and Cooper (and others) suggest increasing such estimates by factors of two and three (“predation rates measured through prey returns may represent one half to less than one third of what pet cats actually kill…” [14]), they should, in fact, be reducing them by half.

Cat Ownership
There are other instances in which simple averages are used to describe similarly skewed distributions—with similar results. That is, they overestimate a particular characteristic—and not in the cats’ favor.

Cat ownership, for example, is not a normal distribution. Many people own one or two cats; a few people own many cats. This is precisely what Lepczyk et al. found in their 2003 study:

“The total number of free-ranging cats across all landscapes was 656, ranging from 1 to 30 per landowner…” [6]

In fact, about 113 (I’m estimating from the histogram printed in the report) of those landowners owned just one cat apiece. About 70 of them owned two cats. Only one—maybe two—owned 30 cats. And yet, Lepczyk et al. calculate an average of 2.59 cats/landowner (i.e., 656 cats/253 landowners who allow their cats outdoors), thereby substantially overestimating cat ownership—and, in turn, predation rates (which calculations are based upon the average number of cats/landowner).

Lepczyk et al. are not the only ones to make this mistake; several other researchers have done the same. [4, 5, 7-9]

Outdoor Access
The amount of time cats spend outdoors is also highly positively skewed, as is apparent from the 2003 survey conducted by Clancy, Moore, and Bertone. [19] Their work showed that nearly half of the cats with outdoor access were outside for two or fewer hours a day. And 29% were outdoors for less than an hour each day.

Among those researchers to overlook the skewed nature of this distribution are Kays and DeWan, who calculate an average of 8.35 hours/day. This greatly overestimates potential predation, and leads them to conclude—erroneously—that the actual number of prey killed by cats was “3.3 times greater than the rate estimated from prey brought home,” [9] as was discussed previously.

Compound Errors
Clearly, these errors are substantial—in some cases, doubling the apparent impact of cats on wildlife. Of course the errors are even more significant when one inflated figure is multiplied by another—as when Lepczyk et al. [6] multiply the average number of prey items returned by the average number of outdoor cats per owner. The resulting predation figures may well be four times greater than they should be! (Actually, there are additional problems with the authors’ predation estimates, which I’ll address in a future post).

* * *

The fact that such a fundamental mistake—one a student couldn’t get away with in a basic statistics course—is made so often is shocking. The fact that such errors slip past journal reviewers is inexcusable.

References
1. Lepczyk, C.A., et al., “What Conservation Biologists Can Do to Counter Trap-Neuter-Return: Response to Longcore et al.” Conservation Biology. 2010. 24(2): p. 627-629.

2. Woods, M., McDonald, R.A., and Harris, S., “Predation of wildlife by domestic cats Felis catus in Great Britain.” Mammal Review. 2003. 33(2): p. 174-188.

3. Coleman, J.S. and Temple, S.A., On the Prowl, in Wisconsin Natural Resources. 1996, Wisconsin Department of Natural Resources: Madison, WI. p. 4–8. http://dnr.wi.gov/wnrmag/html/stories/1996/dec96/cats.htm

4. Baker, P.J., et al., “Impact of predation by domestic cats Felis catus in an urban area.” Mammal Review. 2005. 35(3/4): p. 302-312.

5. Baker, P.J., et al., “Cats about town: is predation by free-ranging pet cats Felis catus likely to affect urban bird populations?“ Ibis. 2008. 150: p. 86-99.

6. Lepczyk, C.A., Mertig, A.G., and Liu, J., “Landowners and cat predation across rural-to-urban landscapes.” Biological Conservation. 2003. 115(2): p. 191-201.

7. Crooks, K.R., et al., “Exploratory Use of Track and Camera Surveys of Mammalian Carnivores in the Peloncillo and Chiricahua Mountains of Southeastern Arizona.” The Southwestern Naturalist. 2009. 53(4): p. 510-517.

8. van Heezik, Y., et al., “Do domestic cats impose an unsustainable harvest on urban bird populations?“ Biological Conservation. 143(1): p. 121-130.

9. Kays, R.W. and DeWan, A.A., “Ecological impact of inside/outside house cats around a suburban nature preserve.” Animal Conservation. 2004. 7(3): p. 273-283.

10. Barratt, D.G., “Predation by house cats, Felis catus (L.), in Canberra, Australia. II. Factors affecting the amount of prey caught and estimates of the impact on wildlife.” Wildlife Research. 1998. 25(5): p. 475–487.

11. Barratt, D.G., “Predation by House Cats, Felis catus (L.), in Canberra, Australia. I. Prey Composition and Preference.” Wildlife Research. 1997. 24(3): p. 263–277.

12. May, R.M., “Control of feline delinquency.” Nature. 1988. 332(March): p. 392-393.

13. Jessup, D.A., “The welfare of feral cats and wildlife.” Journal of the American Veterinary Medical Association. 2004. 225(9): p. 1377-1383.

14. Dauphiné, N. and Cooper, R.J., Impacts of Free-ranging Domestic Cats (Felis catus) on birds in the United States: A review of recent research with conservation and management recommendations, in Fourth International Partners in Flight Conference: Tundra to Tropics. 2010. p. 205–219

15. Longcore, T., Rich, C., and Sullivan, L.M., “Critical Assessment of Claims Regarding Management of Feral Cats by Trap–Neuter–Return.” Conservation Biology. 2009. 23(4): p. 887–894.

16. Winter, L., “Trap-neuter-release programs: the reality and the impacts.” Journal of the American Veterinary Medical Association. 2004. 225(9): p. 1369-1376.

17. Clarke, A.L. and Pacin, T., “Domestic cat “colonies” in natural areas: a growing species threat.” Natural Areas Journal. 2002. 22: p. 154–159.

18. Fitzgerald, B.M. and Turner, D.C., Hunting Behaviour of domestic cats and their impact on prey populations, in The Domestic Cat: The biology of its behaviour, D.C. Turner and P.P.G. Bateson, Editors. 2000, Cambridge University Press: Cambridge, U.K.; New York. p. 151–175.

19. Clancy, E.A., Moore, A.S., and Bertone, E.R., “Evaluation of cat and owner characteristics and their relationships to outdoor access of owned cats.” Journal of the American Veterinary Medical Association. 2003. 222(11): p. 1541-1545.

The Work Speaks—Part 3: Predatory Blending?

31 May 2010•Population Estimates, Threats to Wildlife

“…it may be that conservation biologists and wildlife ecologists believe the issue of feral cats has already been studied enough and that the work speaks for itself, suggesting that no further research is needed.”

In fact, “the work”—taken as a whole—is neither as rigorous nor as conclusive as Lepczyk et al. suggest. And far too much of it is plagued by exaggeration, misrepresentations, errors, and obvious bias. In a previous post, I presented examples of researchers drawing big conclusions from small sample sizes. Here, I’ll discuss the important distinction between compensatory and additive predation—a point too often left out of the feral cat/TNR discussion.

Sins of Omission
Focusing on the number of prey injured or killed by cats, without also recognizing that there are different types of predation, implies that each and every bird, mammal, reptile, etc. is destined to be part of its species’ breeding population. Of course, that’s not at all how things work out in the natural world—with or without predation by cats.

And yet, numerous studies [2-10], reviews [11], and other published papers [12-14] fail to acknowledge the critical difference between compensatory predation (in which prey would have died even in the absence of a particular predator, due to illness, starvation, other predators, etc.) and additive predation (in which healthy prey are killed). It’s the difference between, as Beckerman et al. put it, the “doomed surplus hypothesis” and the “hapless survivor hypothesis.” [15]

This is a critical point when it comes to connecting predation rates (from cats or any other predator) to population impacts. The more additive the predation, the greater the potential impact on population numbers. Purely compensatory predation, on the other hand, is less likely to affect overall populations. Of course, the connection is seldom so simple and direct, and a number of factors (e.g., habitat area and type, base population numbers, etc.) influence the ultimate outcome—making it quite difficult to tease out specific causal relationships. Nevertheless, if we want to better understand the impact of free-roaming cats on wildlife, we cannot ignore the distinction between—and inherent implications of—these two types of predation.

Honorable Mentions
Although Churcher and Lawton failed to mention the distinction between compensatory and additive predation in their now-classic “English village” study [4], Churcher later suggested that their findings were largely in the compensatory category: “If the cats weren’t there, something else would be killing the sparrows or otherwise preventing them from breeding.” [16]

Woods et al. don’t address the topic directly, but warn against drawing direct connections between predation numbers and potential effects on population dynamics:

“Our estimates of the total numbers of animals brought home by cats throughout Britain should be treated with requisite caution and these figures do not equate to an assessment of the impact of cats on wildlife populations.” [3]

Unfortunately, other researchers have used this study to make exactly that connection. In “Critical Assessment,” for example, Longcore et al. cite Woods et al. (along with Lepczyk et al. 2003, the subject of a future post) when they write, “evidence indicates that cats can play an important role in fluctuations of bird populations.” [11]

Under-Compensating?
In their 2008 study, Baker et al. found that “birds killed by cats in this study had significantly lower fat and pectoral muscle mass scores than those killed by collisions,” [17] suggesting that they may have been among the “doomed surplus” portion of the population. Similar results were reported eight years earlier by Møller and Erritzøe, who found that “small passerine birds falling prey to cats had spleens that were significantly smaller than those of conspecifics that died for other reasons,” concluding ultimately that the birds killed by cats “often have a poor health status.” [18]

But Baker et al. express caution about their findings:

“…the distinction between compensatory and additive mortality does… become increasingly redundant as the number of birds killed in a given area increases: where large numbers of prey are killed, predators would probably be killing a combination of individuals with poor and good long-term survival chances.”

Whatever their concerns, it must be noted that Baker et al. inflated their predation numbers by a factor of 3.3 on the basis of Kays and DeWan’s dubious conclusions [9] (which I discussed in some detail previously). Doing so raises considerable doubts about any level of “redundancy,” as well the authors’ suggestion that cat predation in the area might be “creating a dispersal sink for more productive neighboring areas.” [19] (Such “sinks” can occur when predation outstrips local prey populations, requiring that prey be “recruited” from surrounding areas.)

Implications
Given all the work that’s been done on cat predation, one might expect the subject of compensatory predation to be addressed more fully and more often. By omitting this important issue from the feral cat/TNR discussion, researchers portray a situation both simpler and harsher (in terms of what it implies about the impact of free-roaming cats) than reality suggests. Whether or not such omissions are intentional, I cannot say. I do, however, find it curious—what’s included compared to what’s left out, and by whom.

References
1. Lepczyk, C.A., et al., “What Conservation Biologists Can Do to Counter Trap-Neuter-Return: Response to Longcore et al.” Conservation Biology. 2010. 24(2): p. 627-629.

2. Coleman, J.S. and Temple, S.A., On the Prowl, in Wisconsin Natural Resources. 1996, Wisconsin Department of Natural Resources: Madison, WI. p. 4–8. http://dnr.wi.gov/wnrmag/html/stories/1996/dec96/cats.htm

3. Woods, M., McDonald, R.A., and Harris, S., “Predation of wildlife by domestic cats Felis catus in Great Britain.” Mammal Review. 2003. 33(2): p. 174-188.

4. Churcher, P.B. and Lawton, J.H., “Predation by domestic cats in an English village.” Journal of Zoology. 1987. 212(3): p. 439-455.

5. Coleman, J.S. and Temple, S.A., “Rural Residents’ Free-Ranging Domestic Cats: A Survey.” Wildlife Society Bulletin. 1993. 21(4): p. 381–390.

6. Coleman, J.S. and Temple, S.A., Effects of Free-Ranging Cats on Wildlife: A Progress Report, in Fourth Eastern Wildlife Damaage Control Conference. 1989: University of Nebraska—Lincoln. p. 8–12. http://digitalcommons.unl.edu/ewdcc4/7

7. Hawkins, C.C., Impact of a subsidized exotic predator on native biota: Effect of house cats (Felis catus) on California birds and rodents. 1998. PhD Dissertation, Texas A&M University.

8. Hawkins, C.C., Grant, W.E., and Longnecker, M.T., “Effects of Subsidized House Cats on California Birds and Rodents.” Transactions of the Western Section of the Wildlife Society. 1999. 35: p. 29–33.

9. Kays, R.W. and DeWan, A.A., “Ecological impact of inside/outside house cats around a suburban nature preserve.” Animal Conservation. 2004. 7(3): p. 273-283.

10. Lepczyk, C.A., Mertig, A.G., and Liu, J., “Landowners and cat predation across rural-to-urban landscapes.” Biological Conservation. 2003. 115(2): p. 191-201.

11. Longcore, T., Rich, C., and Sullivan, L.M., “Critical Assessment of Claims Regarding Management of Feral Cats by Trap–Neuter–Return.” Conservation Biology. 2009. 23(4): p. 887–894.

12. Dauphiné, N. and Cooper, R.J., Impacts of Free-ranging Domestic Cats (Felis catus) on birds in the United States: A review of recent research with conservation and management recommendations, in Fourth International Partners in Flight Conference: Tundra to Tropics. 2010. p. 205–219

13. Coleman, J.S., Temple, S.A., and Craven, S.R., Cats and Wildlife: A Conservation Dilemma. 1997, University of Wisconsin, Wildlife Extension. http://forestandwildlifeecology.wisc.edu/wl_extension/catfly3.htm

14. Andersen, M.C., Martin, B.J., and Roemer, G.W., “Use of matrix population models to estimate the efficacy of euthanasia versus trap-neuter-return for management of free-roaming cats.” Journal of the American Veterinary Medical Association. 2004. 225(12): p. 1871-1876.

15. Beckerman, A.P., Boots, M., and Gaston, K.J., “Urban bird declines and the fear of cats.” Animal Conservation. 2007. 10(3): p. 320-325.

16. n.a., What the Cat Dragged In, in Catnip. 1995, Tufts University School of Veterinary Medicine: Boston, MA. p. 4–6

17. Baker, P.J., et al., “Cats about town: is predation by free-ranging pet cats Felis catus likely to affect urban bird populations?“ Ibis. 2008. 150: p. 86-99.

18. Møller, A.P. and Erritzøe, J., “Predation against birds with low immunocompetence.” Oecologia. 2000. 122(4): p. 500-504.

The Work Speaks—Part 2: Sample-Minded Research

27 May 2010•Population Estimates, Research Protocol, The Cat Debate, Threats to Wildlife

“…it may be that conservation biologists and wildlife ecologists believe the issue of feral cats has already been studied enough and that the work speaks for itself, suggesting that no further research is needed.”

In fact, “the work”—taken as a whole—is neither as rigorous nor as conclusive as Lepczyk et al. suggest. And far too much of it is plagued by exaggeration, misrepresentations, errors, and obvious bias. In my previous post, I presented examples of researchers “reinterpreting” the work of others to better fit their own arguments. For the next few posts, I’ll focus on some of the major flaws in the feral cat/TNR research itself—beginning with the reliance, by some, on small sample sizes.

Size Does Matter
There are all kinds of reasons for small sample sizes, perhaps the most common being limited resources (e.g., time, funding, etc.). And they are often a fact of life in real-world research, where investigators have less control over conditions than they might in a laboratory environment. Studies employing small sample sizes are not without value; indeed, they often serve as useful pilot studies for future, more comprehensive, work. They do become problematic, though, when broad conclusions are drawn from their results. Below are three (among many!) examples of such studies.

Impressive Estimates
In “Free-Ranging Domestic Cat Predation on Native Vertebrates in Rural and Urban Virginia,” [2] published in 1992, the authors estimated that the state’s 1,048,704 cats were killing between 3,146,112 and 26,217,600 songbirds each year. “This number,” they note, “is certainly inaccurate to some degree, although the estimates are impressive.” [2] Impressive? I suppose. Maybe incredible is more fitting—since the study from which they were derived included exactly five cats, four “urban” and one “rural.”

Mitchell and Beck acknowledged “the limitations of extrapolation to large areas from relatively small data sets such as ours,” suggesting that their work was intended to provoke future “careful and detailed studies that can reveal truer estimates of the impact of this introduced species.” Hawkins [3] and Dauphiné and Cooper [4], however, seem to take them at their word, regardless of any disclaimers.

Many Cats, Multiple Seasons
In a recent study on Catalina Island, the researchers “examined the home-range behavior and movements of sterilized and intact radiocollared feral cats living in the interior” [5] of the island. Although Guttilla and Stapp concede that “sample sizes, especially for males, were relatively low” despite having “tracked many cats across multiple seasons,” they nevertheless come to some rather dramatic conclusions. Among them: “sterilization likely would not reduce the impact of feral cats on native prey.” [5]

So what do the authors mean by many and multiple? Actually, there were just 27 cats in the study (of an estimated 614–732 on the island). “Four cats were tracked during all four seasons, 9 cats were tracked for three consecutive seasons, 4 cats were tracked for 2 consecutive seasons, and the remaining cats were tracked for 1 season.” [5] And these numbers were effectively cut in half, because the researchers were comparing sterilized and non-sterilized cats. At best, this is a pilot study—though it’s already morphed into something more substantial in the mainstream media.

Myth vs. Math
In their 2004 study, “Ecological Impact of Inside/Outside House Cats Around a Suburban Nature Preserve,” Kays and DeWan observed hunting cats, concluding that their kill rate (13%) is “3.3 times greater than the rate estimated from prey brought home.” [6] Not surprisingly, this figure has been used as an instant multiplier (much in the same way William George’s work has been misused) for researchers interested in “correcting” (inflating?) prey numbers. [4, 7-11]

But this ratio, 3.3, hinges on the hunting behaviors of just 24 cats—12 that returned prey home, and another 12 (11 pets and 1 feral) that were observed hunting for a total of 181 hours (anywhere from 4.8–46.5 hours per cat). It’s interesting to note that the cat observed the most (46.5 hours) was only a year old—the youngest of the 12 observed, and likely the most active hunter. This factor alone could have had a significant influence on the outcome of the study.

Also, as several studies have shown [7,8,12,13], the distribution of prey catches tends to be highly skewed (many cats catch few/no prey, while a few catch a lot). In other words, the distribution is not the familiar bell curve at all—making it inappropriate to use a simple average for calculating estimations (a topic I’ll address in detail later). What’s more, with only 12 cats being monitored, how can we be sure their behaviors accurately represent any real distribution at all?

But the key to their calculation is the average time spent outdoors. This, too, tends to be a highly skewed distribution [14, 15], although—curiously—Kays and DeWan’s data suggest otherwise. By way of example, a 2003 survey conducted by Clancy, Moore, and Bertone [15] revealed that nearly half of the cats with outdoor access were outside for two or fewer hours a day. And 29% were outdoors for less than an hour each day. A survey conducted by the American Bird Conservancy revealed similar behavior, reporting that “35% keep their cats indoors all of the time” and “31% keep them indoors mostly with some outside access.” [14]

Kays and DeWan’s average of 8.35 hours/day, then, seems rather out of line with other studies. This, in addition to a number of unknowns (e.g., influence of time of day/night on hunting success, actual time spent hunting by each cat, etc.) raises serious questions about their conclusions.

By way of comparison, using an average of 2.5 hours/day (which is not out of line with the surveys described above) would yield a ratio of 1:1. In other words, no difference between predation rates predicted by actual hunting observation and those predicted by way of prey returned home. Which is not to say that I agree with Kays and DeWan’s underlying methods—we don’t know the possible effects of seasonal variation, for example, or differences in habitat. I’m only pointing out how sensitive this one factor—with its enormous consequences—is to the amount of time cats actually spend outdoors (and, just to introduce one more complication: I’d be very surprised if the amount of outdoor time cats spend hunting is normally distributed; it, too, is probably skewed).

Ironically, while the authors express disappointment that “biologists have rarely sampled both cat and prey populations in such a way that direct effects on prey populations can be shown,” [6] they seem to have had no misgivings about how their work—suffering from its own sampling issues—might be used to misrepresent those same effects.

* * *

Next, I’ll discuss the difference between compensatory and additive predation, and how that affects predictions of feral cat impacts on wildlife.

References
1. Lepczyk, C.A., et al., “What Conservation Biologists Can Do to Counter Trap-Neuter-Return: Response to Longcore et al.” Conservation Biology. 2010. 24(2): p. 627-629.

2. Mitchell, J.C. and Beck, R.A., “Free-Ranging Domestic Cat Predation on Native Vertebrates in Rural and Urban Virginia.” Virginia Journal of Science. 1992. 43(1B): p. 197–207.

3. Hawkins, C.C., Impact of a subsidized exotic predator on native biota: Effect of house cats (Felis catus) on California birds and rodents. 1998. PhD Dissertation, Texas A&M University.

4. Dauphiné, N. and Cooper, R.J., Impacts of Free-ranging Domestic Cats (Felis catus) on birds in the United States: A review of recent research with conservation and management recommendations, in Fourth International Partners in Flight Conference: Tundra to Tropics. 2010. p. 205–219

5. Guttilla, D.A. and Stapp, P., “Effects of sterilization on movements of feral cats at a wildland-urban interface.” Journal of Mammalogy. 2010. 91(2): p. 482-489.

6. Kays, R.W. and DeWan, A.A., “Ecological impact of inside/outside house cats around a suburban nature preserve.” Animal Conservation. 2004. 7(3): p. 273-283.

7. Baker, P.J., et al., “Impact of predation by domestic cats Felis catus in an urban area.” Mammal Review. 2005. 35(3/4): p. 302-312.

8. Baker, P.J., et al., “Cats about town: is predation by free-ranging pet cats Felis catus likely to affect urban bird populations?“ Ibis. 2008. 150: p. 86-99.

9. van Heezik, Y., et al., “Do domestic cats impose an unsustainable harvest on urban bird populations?“ Biological Conservation. 143(1): p. 121-130.

10. Nelson, S.H., Evans, A.D., and Bradbury, R.B., “The efficacy of collar-mounted devices in reducing the rate of predation of wildlife by domestic cats.” Applied Animal Behaviour Science. 2005. 94(3-4): p. 273-285.

11. MacLean, M.M., et al., “The usefulness of sensitivity analysis for predicting the effects of cat predation on the population dynamics of their avian prey.” Ibis. 2008. 150(Suppl. 1): p. 100-113.

12. Churcher, P.B. and Lawton, J.H., “Predation by domestic cats in an English village.” Journal of Zoology. 1987. 212(3): p. 439-455.

13. Woods, M., McDonald, R.A., and Harris, S., “Predation of wildlife by domestic cats Felis catus in Great Britain.” Mammal Review. 2003. 33(2): p. 174-188.

14. ABC, Human Attitudes and Behavior Regarding Cats. 1997, American Bird Conservancy: Washington, DC. http://www.abcbirds.org/abcprograms/policy/cats/materials/attitude.pdf

15. Clancy, E.A., Moore, A.S., and Bertone, E.R., “Evaluation of cat and owner characteristics and their relationships to outdoor access of owned cats.” Journal of the American Veterinary Medical Association. 2003. 222(11): p. 1541-1545.

The Work Speaks—Part 1: Lost in Translation

24 May 2010•Cats and Birds, Research Protocol, The Cat Debate, Threats to Wildlife

“…it may be that conservation biologists and wildlife ecologists believe the issue of feral cats has already been studied enough and that the work speaks for itself, suggesting that no further research is needed.”

In fact, “the work”—taken as a whole—is neither as rigorous nor as conclusive as Lepczyk et al. suggest. And far too much of it is plagued by exaggerations, misrepresentations, errors, and obvious bias. For the next few posts, I’m going to present a sampling of its more serious flaws, beginning with how some researchers “reinterpret” work of others to suit their own purposes.

Tell It Like It Is
Studies of cat predation frequently cite the work of William G. George, who, in 1974, published a paper documenting his meticulous observations of the hunting behavior of three cats on his southern Illinois farm. “The results,” wrote George, “established a basis for examining the possibility that cat predation may result in depleted winter populations of microtine rodents and other prey of Red-tailed Hawks, Marsh Hawks, and American Kestrels.” [2]

Thirty years later, David A. Jessup interpreted things rather differently, giving George’s work an additional—and unwarranted—degree of certainty. Gone are the doubts that George expressed—first, regarding the impact of cat predation on rodent and other prey populations; second, regarding the relationship between these populations and the raptors that feed on them. For Jessup—who offers no additional evidence—it’s all very straightforward: “Feral cats also indirectly kill native predators by removing their food base.” [3]

More recently, Guttilla and Stapp seem to prefer Jessup’s take: “Human-subsidized cats… can spill over into less densely populated wildland areas where they reduce prey for native predators (George 1974).” [4]

If any additional work has been done on the subject (surely there are more cats in the area these days; how are the voles and raptors faring?), it seems to have gone unnoticed. Instead, Jessup, Guttilla, and Stapp (and others, too, no doubt) have simply rewritten George’s conclusion to suit their own purposes. Perhaps their version makes for a better story, but it’s rather poor science.

Credit Where Little/None Is Due
When the Lancet recently retracted a 1998 paper linking vaccinations to autism in children—“research” that sparked the ongoing backlash against vaccinations—it was headline news. The move prompted this criticism from one member of the British Parliament: “The Lancet article should never have been published, and its peer review system failed. The article should now be expunged from the academic record…”

At the risk of drawing too many parallels between the two papers, I think the same can be said for Coleman and Temple’s infamous “Wisconsin Study.” (On the other hand, it does serve a useful purpose as a red flag.) Actually, as Goldstein et al. point out, Coleman and Temple’s paper was never peer-reviewed (not necessarily a deal-breaker in my book, but such publications do warrant additional scrutiny), but achieved its mythical status by being cited ad nauseam in peer-reviewed journals, as well as the mainstream media.

Does anybody actually believe the numbers suggested by Coleman and Temple? Stanley Temple (one of the co-authors of the recent anti-feral cat/TNR comment in Conservation Biology) himself admitted their published figures “aren’t actual data; that was just our projection to show how bad it might be.” [5]

I don’t think Longcore et al. [6] or the editors at Conservation Biology put much stock in the Wisconsin Study—so why continue to publish “projections” that have been so thoroughly discredited? Because doing so strengthens their case, at least among those who don’t know any better—especially people outside the scientific community, including many journalists, policy makers, judges, and the general public.

In their recent comment, Lepczyk et al. suggest that conservation biologists and wildlife ecologists “look to the evolutionary biology community” [1] for an example of how to influence policy:

“When local policies or regulations are put forth that promote the teaching of creationism or intelligent design, the evolutionary biologists have responded in force from across the nation and world.” [1]

Let’s set aside for the moment all the baggage associated with their analogy. My question is this: Is the evolutionary biology community still publishing bogus “projections” from 13 years ago? I doubt it.

Check Your Premises
In their recent paper (available for download via the American Bird Conservancy (ABC) website), Dauphiné and Cooper arrive at their absurd figure of “117–157 million free-ranging cats in the United States,” [7] in part, by way of Jessup’s “estimated 60 to 100 million feral and abandoned cats in the United States.” [3]

So where does Jessup’s figure come from? We have no idea—there’s no citation. And Jessup is no authority on the subject—having conducted no studies or reviews of studies that quantify the feral cat population. What’s more, his “estimation” is among the highest figures published. Yet this is the shaky foundation upon which Dauphiné and Cooper attempt to build their subsequent argument.

The authors then add to the (dubious) number of feral cats the proportion of pet cats allowed outdoors. They refer to a 2004 paper by Linda Winter, director of ABC’s Cats Indoors! campaign, in which it was reported, “A 1997 nationwide random telephone survey indicated that 66% of cat owners let their cats outdoors some or all of the time.” [8]

That’s an interesting way to put it—Winter makes it sound like two-thirds of pet cats are essentially outdoor cats. But the survey—commissioned by ABC!—actually indicates that “35% keep their cats indoors all of the time” and “31% keep them indoors mostly with some outside access.” [9] The difference in wording is subtle, and hampered by imprecision—it all comes down to the meaning of some.

Winter’s 2004 paper implies that there are twice as many outdoor pet cats as was indicated in the original survey—an interpretation Dauphiné and Cooper seem to embrace. Had they looked further—and to a less biased source—they might have been able to get a better handle on the degree of outdoor access. For example: a 2003 survey conducted by Clancy, Moore, and Bertone [10] revealing that nearly half of the cats with outdoor access were outside for two or fewer hours a day. And 29% were outdoors for less than an hour each day.

Do these “part-timers” have the same impact on wildlife as feral cats? Dauphiné and Cooper would have us believe they do.

[Note: For a closer look at the flaws in Dauphiné and Cooper’s paper, download “One Billion Birds,” by Laurie D. Goldstein.]

The lesson? Credible research begins with a solid foundation; a weak foundation—one plagued with unsubstantiated claims—on the other hand, leads to pseudoscience.

Or worse. ABC’s Senior Policy Advisor, Steve Holmer, cited Dauphiné and Cooper’s bogus numbers when he spoke to the Los Angeles Times about his organization’s involvement with the legal battle against TNR. It’s like the Wisconsin Study all over again.

When All Else Fails, Look It Up
Though this would seem to be utterly obvious, it apparently bears repeating: Don’t cite work you haven’t actually read.

Isn’t this emphasized in all graduate (indeed, undergraduate, too) programs? What grad student isn’t, at one time or another, tempted to take the easy way out—ride the coattails of somebody else who’s (presumably) done the real work? In addition to the ethical implications, such shortcuts tend to invite more immediate troubles, too. Again, George’s work (described above) provides an excellent case study. Below are some examples of how his work has been referenced in the cat predation literature:

“It is very unlikely that cats bring home all of the prey that they capture. What proportion they bring home has been little studied. George (1974) on a farm in Illinois USA found that three house cats, all adequately fed, brought home about 50% of the prey that they killed.” [11]

“George found that about 50% of prey were indeed brought home, with the other 50% being eaten, scavenged by other animals or simply not found.” [12]

“These approximations are probably underestimates, assuming that cats do not bring back all the prey that they kill.” [13]

Trouble is, George never said these things; what he said was:

“… the cats never ate or deposited prey where caught but instead carried it into a ‘delivery area,’ consisting of the house and lawn. The exclusive use of this delivery area was verified in 18 to 70 mammal captures per cat, as witnessed between early 1967 and 1971.” [2]

In 2000, Fitzgerald and Turner pointed out the fact that George’s work was being misrepresented, noting that the erroneous 50% figure “has been reported widely, though it is unfounded.” [14] Nevertheless, the myth persists—even in 2010.

“In Illinois, George (1974) found that only about half of animals killed by cats were provided to their owners, and in upstate New York, Kays and DeWan (2004) found that observed cat predation rates were 3.3 times higher than predation rates measured through prey returns to owners. Thus, predation rates measured through prey returns may represent one half to less than one third of what pet cats actually kill…” [7]

As Dauphiné and Cooper demonstrate, the “reinterpreted” version of George’s work makes for a very convenient multiplier—suddenly, every kill reported is doubled (or tripled, if Kays and DeWan are to be believed—and they’re not, but that’s a topic for another post). Never mind the fact that it has no basis in actual fact.

Getting a copy of George’s study isn’t difficult, especially with the inter-library loan services available today. To reference it—to use George’s work so that your own appears more credible—without ever having actually read it, is simply inexcusable. But citing it blindly suggests more than laziness—it points to a certain coziness that has no place in scientific discourse. Too much Kool-Aid drinking, and not enough honest research.

* * *

Scientists can (and do) look at identical results and come to very different conclusions. But misinterpreting, misrepresenting, or dismissing the conclusions of others, is something else altogether. As the above examples (and there are many, many more!) illustrate, this happens far too often in the feral cat/TNR literature. And if we can’t believe what researchers are saying about the work of others, why would we believe what they say about their own work?

Next, I’ll focus on some of the major flaws in the feral cat/TNR literature—beginning with small sample sizes…

References
1. Lepczyk, C.A., et al., “What Conservation Biologists Can Do to Counter Trap-Neuter-Return: Response to Longcore et al.” Conservation Biology. 2010. 24(2): p. 627-629.

2. George, W., “Domestic cats as predators and factors in winter shortages of raptor prey.” The Wilson Bulletin. 1974. 86(4): p. 384–396.

3. Jessup, D.A., “The welfare of feral cats and wildlife.” Journal of the American Veterinary Medical Association. 2004. 225(9): p. 1377-1383.

4. Guttilla, D.A. and Stapp, P., “Effects of sterilization on movements of feral cats at a wildland-urban interface.” Journal of Mammalogy. 2010. 91(2): p. 482-489.

5. Elliott, J., The Accused, in The Sonoma County Independent. 1994. p. 1, 10

6. Longcore, T., Rich, C., and Sullivan, L.M., “Critical Assessment of Claims Regarding Management of Feral Cats by Trap–Neuter–Return.” Conservation Biology. 2009. 23(4): p. 887–894.

8. Winter, L., “Trap-neuter-release programs: the reality and the impacts.” Journal of the American Veterinary Medical Association. 2004. 225(9): p. 1369-1376.

9. ABC, Human Attitudes and Behavior Regarding Cats. 1997, American Bird Conservancy: Washington, DC. http://www.abcbirds.org/abcprograms/policy/cats/materials/attitude.pdf

10. Clancy, E.A., Moore, A.S., and Bertone, E.R., “Evaluation of cat and owner characteristics and their relationships to outdoor access of owned cats.” Journal of the American Veterinary Medical Association. 2003. 222(11): p. 1541-1545.

11. Churcher, P.B. and Lawton, J.H., “Predation by domestic cats in an English village.” Journal of Zoology. 1987. 212(3): p. 439-455.

12. May, R.M., “Control of feline delinquency.” Nature. 1988. 332(March): p. 392-393.

13. Crooks, K.R. and Soule, M.E., “Mesopredator release and avifaunal extinctions in a fragmented system.” Nature. 1999. 400(6744): p. 563.

Hold Your Applause

20 May 2010•In the News, The Cat Debate

Three months after my letter to Conservation Biology was rejected, it’s become apparent what they were really looking for: applause, not criticism.

Of course it probably doesn’t help that I’m not a member of the club; I don’t even know the secret handshake. (Michael Hutchins, writing for the Wildlife Society Blog, “Making Tracks,” has accused me—an outsider—of trying to “out-science the scientists.”)

In April, Conservation Biology published a comment authored by Christopher A. Lepczyk, Nico Dauphiné, David M. Bird, Sheila Conant, Robert J. Cooper, David C. Duffy, Pamela Jo Hatley, Peter P. Marra, Elizabeth Stone, and Stanley A. Temple. The authors “applaud the recent essay by Longcore et al. (2009) in raising the awareness about trap-neuter-return (TNR) to the conservation community,” [1] and puzzle at the lack of TNR opposition among the larger scientific community.

The reasons behind this lack of opposition are unclear, but it may be that conservation biologists and wildlife ecologists believe the issue of feral cats has already been studied enough and that the work speaks for itself, suggesting that no further research is needed. Or, they simply do not want to devote time and energy to the issue and are unaware of policy actions.

I’d like to offer an alternative explanation. Yes, the work speaks for itself, but there are plenty of observers—surely, there are conservation biologists and wildlife ecologists among them—who don’t particularly like what it’s saying.

For the next few posts, then, I’m going to present a sampling of the more serious flaws—including exaggerated and misleading claims, botched analyses, questionable research and review methods, and widespread bias—all too common in the feral cat/TNR literature. Let’s see what Lepczyk at al. are cheering about…

References
1. Lepczyk, C.A., et al., “What Conservation Biologists Can Do to Counter Trap-Neuter-Return: Response to Longcore et al.” Conservation Biology. 2010. 24(2): p. 627-629.