TNR Opponents’ Reaction(?) to the Recovery of the California Sea Otter

Photo: Wikipedia/Michael L. Baird

For several years now, TNR opponents have blamed Toxoplasma gondii infection in California sea otters on outdoor cats, the idea being that the parasite is spread from cat feces into the soil and then flushed into the Pacific by way of runoff. From the start, it’s been a dubious argument—requiring believers to focus narrowly on specific data while ignoring a great deal more.

And the argument has only grown increasingly weak in recent years, as additional research findings have further questioned the role of domestic cats in sea otter infection. Perhaps most compelling of all are the results of the 2016 sea otter census, which estimates that the population along the California coast might be greater than it’s been in more than 100 years.

So how do TNR opponents reconcile these findings with their claims that outdoor cats pose a grave threat to the sea otters?

They don’t, of course.

Instead, they simply ignore the research—all the while telling anybody who will listen that they have science on their side. Read more

Thinking Inside the Box

It’s difficult to determine how these things get started—how the results of a well-documented experiment conducted nearly 40 years ago become twisted into the frequently made—and widely-accepted—claim that “even well-fed cats hunt.”

This would appear to be a case of validity through repetition: repeat a claim often enough and, eventually, people will come to believe it’s true—never bothering to check the original source. (Pro Tip: For added efficacy, click the heels of your ruby-red slippers together while repeating the claim.)

This, it should go without saying, is not how science is supposed to work. Read more

War on Nature, War on Cats

In Nature Wars, to be released next week, award-winning journalist Jim Sterba argues that it’s time for Americans to reconnect with nature—and what better incentive than a massive lethal control campaign against any number of plants and animals, including feral cats? His book reflects attitudes that are out of step with contemporary culture, and a rationale that’s not supported by the science. As the song says: War! What is it good for? Absolutely nothin’…

“People have very different ideas regarding what to do, if anything, about the wild creatures in their midst,” writes Jim Sterba in his new book Nature Wars: The Incredible Story of How Wildlife Comebacks Turned Backyards Into Battlegrounds, “even when they are causing problems.”

“Enjoy them? Adjust to them? Move them? Remove them? Relations between people and wildlife have never been more confused, complicated, or conflicted.” [1]

Agreed. And I largely agree with Sterba’s diagnosis: “Americans have become denatured.”

“That is to say, they have forgotten the skills their ancestors acquired to manage an often unruly natural world around them, and they have largely withdrawn from direct contact with that world by spending most of their time indoors, substituting a great deal of real nature with reel nature—edited, packaged, digitized, and piped in electronically.” [1]

So what’s the solution? Here, Sterba and I part company. Read more

Free-Roaming Cats, Infectious Diseases, and the Zombie Apocalypse

A recently published paper describing free-roaming cats as “a significant public health threat” fails to deliver convincing evidence. In fact, the very work the authors cite undermines, time and time again, their claims.

“Domestic cats are a potential source of numerous infectious disease agents,” write Rick Gerhold and David Jessup, in their paper, “Zoonotic Diseases Associated with Free-Roaming Cats,” published online in July by the journal Zoonoses Public Health (and to be included in an upcoming print edition).

“However, many of these diseases are controlled in cats belonging to responsible owners through routine veterinary care, proper vaccination regimens and parasite chemotherapy. Free-roaming cats often lack the necessary preventative care to control these diseases and consequently pose a potential health threat to other domestic animals, wildlife and humans.” [1]

Just how much of a threat do these cats pose?

Gerhold and Jessup would have us believe that the risks are high and the consequences dire. A careful reading of their paper, however, reveals the authors’ tendency to cherry-pick some studies and misrepresent others. And, occasionally, simply get their facts wrong.*

All of which raises serious questions about Gerhold and Jessup’s case against free-roaming cats. Read more

The Silent Treatment

“I don’t want to be sort of a poodle dog when I’m out there, and a friendly sort of presence in people’s lives,” explained New York Times reporter David Carr in an October 2011 interview with Fresh Air host Terry Gross, “and then come back and do something that’s really mean or aggressive.”

“And if it’s gonna be a hard story, one of things I always say is: This is gonna be a really serious story, and I’m asking very serious questions. And it behooves you to think it through and really work on answering, and defending yourself, because this is not a friendly story. And if they don’t engage, I just tell them: Well, you know what? You better put the nut-cup on, because this is not gonna be pleasant for anyone.

Two months later, I heard the interview as part of a year-end compilation of the show’s most memorable conversations. Carr’s comments struck a chord; just three weeks earlier, following the publication of “Perceived Predation Risk Reduces the Number of Offspring Songbirds Produce per Year” in Science, I was unable to get co-authors Liana Zanette and Michael Clinchy to “engage.”

Which I found both frustrating and puzzling.

Clearly, these two are eager to talk about domestic cats (see, for example, Clinchy’s comments in ScienceNOW and Zanette’s in the Winnipeg Free Press), even when their work has nothing at all to do with them (or, given the absurd methods employed, real-world predation in general). And here I am—pretty much all cats, all the time—reaching out, only to be snubbed.

During his Fresh Air interview, Carr refers to his October 23 column (“basically a screed,” he says), in which he took on big media—in particular, The Tribune Company and Gannett.

“I spent four days [in June] trying to get comments on Gannett [executive] bonuses, and on Sunday night they said, ‘We’re not going to comment on these bonuses.’ And I just said: Really? You’re a newspaper company. You’re a publicly held company. These bonuses are a matter of public record, and you have nothing to say about them? And I just found that appalling, and I think some of that was reflected in the piece.”

“Clearly,” added Carr, explaining the crux of his frustration, “they were living a life beyond consequence.”

Again, I’m reminded of Zanette and Clinchy. These two led a study in which contrived methods rendered the work nearly worthless—and then went on to misrepresent the study’s implications to the media. And what consequences will they face? None, I suspect. After all, the research did receive funding, and the resulting paper was published in a prestigious journal.

All of which paves the way for more of the same.

Not that Zanette and Clinchy are exceptional in this regard. Since launching this blog in April 2010, I’ve had numerous e-mail inquiries go unanswered. Scientists, journalists, officials of various agencies and organizations, etc.—people eager to get their message out, clearly, but unwilling to respond when that message is challenged. I’d always thought such scrutiny not only came with the territory, but was also welcome—a necessary tool for shaping better science, reporting, and policy.

Others apparently disagree. Among those with whom I have a decidedly one-way correspondence:

Melissa Miller, Wildlife Pathologist, California Department of Fish and Game
Miller was one of 14 co-authors to link the Type X strain of T. gondii—responsible for nearly three-quarters of sea otter infections, according to one study [1]—to wild felids (e.g., mountain lions and bobcats) rather than domestic cats.

“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.” [2]

Now, one needs to be very careful about making conclusions based on such small sample sizes. Nevertheless, given (1) the unprecedented (as far as I can tell) nature of these findings, and (2) the nature of the current “cat debate”—in which free-roaming cats are being vilified in both the scientific literature and mainstream media—this would certainly seem to be newsworthy.

And yet, just two paragraphs later, the paper goes into detail about the estimated mass of “feline fecal deposition” created by domestic cats in the communities near Estero Bay. Suddenly, the focus is back on domestic cats.

I asked her about this in July of 2010, but received no response.

(Nine months later, in a special section of the Spring issue of The Wildlife Professional, Miller and David Jessup (another of the 14 co-authors on the 2008 paper, and a colleague of Miller’s at the California Department of Fish and Game) were at it again, arguing simply, “the science points to cats.” [3])

Christine Stracey, Assistant professor of biology at Westminster College
“I thought the cats probably really hammered them when they were fledglings,” said Stracey, a former University of Florida doctoral student in a UF press release about her study of Northern mockingbirds, “but when they were in the nests, I didn’t really expect the cats to be a huge problem. But I was really wrong about that.”

Once again, the underlying science fails to live up to the dramatic press release. Dig into the details of Stracey’s study, and it becomes clear that she’s probably overestimating the strength of cats as urban predators. Perhaps considerably. In fact, her nest camera placement almost certainly biased her data.

In short, it seems Stracey observed predation by cats largely because she placed the cameras where the cats were.

“We need to think hard about the feral cat problem,” warns Stracey in the press release. But if, as she suggests, cats are a “huge problem,” then how to explain the fact—as Stracey notes in the very same press release—Northern mockingbirds have proven “able to not only live with us, but do really well living with us” [and our cats]? These birds are, as she puts it, “urban winners.”

I asked Stracey about all of this by way of e-mail, but received no response. My follow-up e-mail also went unanswered, but I did notice some Website traffic from the Salt Lake City area (where Westminster College is located) that same day. Coincidence? Could be.

The same goes for the traffic from Columbus, OH, following my e-mail to Amanda Rodewald, professor of wildlife ecology at Ohio State University.

“There are a lot of loud voices that deny cats are important predators of birds in our cities,” argued Rodewald (whose relationship to Stracey’s work remains a mystery) in the UF press release. “But this study shows clearly that cats were the dominant predator in this Florida system—and that wasn’t presumed, it was recorded on video, so it was fact.”

When I wrote to Rodewald, I identified myself as one of those “loud voices,” explaining that I wasn’t asking her to speak for Stracey, nor to defend the research. But, given her own research interest—and her obvious concern with Stracey’s work—perhaps she might be able to answer one question for me: What impact might we expect on the area’s Northern mockingbird populations if the cats were removed from the environment?

It was, apparently, one question too many.

Michael E. Grigg, National Institutes of Health
Like Zanette and Clinchy, Grigg, who serves as Chief of the Molecular Parasitology Unit at the National Institute of Allergy and Infectious Diseases (part of NIH), used a PR opportunity to misrepresent his work. “The most remarkable finding of our study,” notes Grigg in an NIH press release, “was the exacerbating role that [Sarcocystis] neurona appears to play in causing more severe disease symptoms in those animals that are also infected with T. gondii.”

So, the story is more complicated than is typically acknowledged—T. gondii may not be the culprit it’s so often made out to be.

But Grigg is still hanging his hat—in spite of his own findings—on simple environmental contamination:

“Identifying the threads that connect these parasites from wild and domestic land animals to marine mammals helps us to see ways that those threads might be cut… by, for example, managing feral cat and opossum populations, reducing run-off from urban areas near the coast, monitoring water quality and controlling erosion to prevent parasites from entering the marine food chain.”

In fact, Grigg and his colleagues found that “T. gondii infections peaked in 2007 then declined relative to S. neurona.” [4] Could it be that free-roaming domestic cats—generally presumed to be the primary source of T. gondii contamination—are also on the decline? TNR opponents don’t seem to think so.

And the researchers observed that infection rates associated with inland waters were no greater than in mammals found along the outer coast. Again, this raises serious questions about the role of domestic cats (which, one would presume, are more numerous inland). As do the numerous studies pointing to sources other than environmental contamination [5–7]—vertical transmission, [5] for example, and possibly ticks [8]—none of which Grigg and his colleagues acknowledge.

Then, of course, there are Grigg’s proposed solutions—first and foremost: “managing feral cat and opossum populations.” Even setting aside for the moment the numerous hurdles (e.g., ethical, economic, etc.) involved with the mass removal/reduction/eradication of these animals, what impact could we realistically expect in terms of T. gondii and/or S. neurona infections in marine mammals? (And what other consequences would we then face?)

I assume Grigg has given the subject considerable thought, but—so far, anyhow—he’s been unwilling to share those thoughts with me.

Steve Klett, Crocodile Lake National Wildlife Refuge Manager
I first ran across Klett’s name in the Florida Keys National Wildlife Refuges Complex Integrated Predator Management Plan/Draft Environmental Assessment, where he was cited as the source for the claim that “cats accounted for 77 percent of the mortality during a recent re-introduction of the Key Largo woodrat.” [9] If, as USFWS has suggested, there are only about 500 woodrats in the wild, [10] why not disclose precisely how many were involved in this “recent re-introduction”? Seventy-seven percent out of how many?

Thirteen, as far as I’ve been able to determine. That’s how many were apparently released in November 2010—following the release of 14 others in February. And, according to attorney and Endangered Species Act blogger Keith Rizzardi, 13 more were released in April 2011.

I e-mailed Klett in July, asking him to clarify that 77 percent figure (which, let’s face it: does a far better job of fanning the flames of the witch-hunt for feral cats than, say, “10 out of 13” does), but never heard back.

Klett retired in December, but Chad Anderson, USFWS biologist at the refuge, assures me that I can “look forward to that [77 percent figure] going from a personal comm. quote to a referenced white paper in the final IPM plan.”

I’m not holding my breath.

Timothy O’Hara, Reporter for the Key West Citizen
In an August 30, 2011 story for the Key West Citizen, Timothy O’Hara writes: “Research indicates that cat predation accounts for 50 percent to 77 percent of the deaths of Lower Keys marsh rabbits and Key Largo woodrats.”

One-half to three-quarters? Really?

Actually, no.

That 77 percent, of course, comes from Klett’s “personal communication”—and seems to reflect the 10 mortalities described above. (Another question I asked Klett was how they could be sure that cats were the culprits. It’s been suggested by a volunteer involved with the re-introductions that the evidence comes from camera traps on the refuge, but I know of no such information coming from refuge officials.)

The 50 percent figure, I’m quite sure, can be traced to Elizabeth Forys’ PhD work, done in the early 1990s on Navy-owned land on Boca Chica and Saddlebush Key. Forys found that 13 of 24 marsh rabbits monitored over the course of her two-and-a-half year study were killed by cats. [11] (USFWS misrepresents this, too, in its Predator Management Plan, once again omitting the number of mortalities: “Free-roaming domestic cat predation accounted for 50 percent of adult Lower Keys marsh rabbit mortality during radio telemetry studies…” [9])

Turns out, O’Hara wasn’t interested in being fact-checked; he never replied to my e-mail.

(If O’Hara is interested in real journalism, he might consider an investigative piece about how USFWS routinely plays misleads the public to whom they are ostensibly accountable.)

Darin Schroeder, ABC’s Vice President for Conservation Advocacy
In October, Schroeder sent a letter (PDF) to the mayors of the 50 largest cities in the country, urging them “to oppose Trap-Neuter-Re-abandon (TNR) programs and the outdoor feeding of cats as a feral cat management option.” In it, he trots out the usual laundry list of misleading complaints: predation, rabies, vague threats regarding the possible implications of the Endangered Species Act and the Migratory Bird Treaty Act, etc.

When I wrote to Schroeder, I made it clear that we need not get into all of this. I just wanted him to explain how feeding bans and policy directives opposing TNR would, as ABC suggests in its November 9 media release, “stop the spread of feral cats.” After all, common sense—and science—tells us that such policies (assuming they could be enforced, of course) would only drive population numbers upward. If, as Schroeder claims, there are “well-documented impacts of cat predation on wildlife,” how could an increase in the population of cats possibly be a benefit?

That was nearly two months ago now; I’m still waiting for Schroeder to connect the dots for me.

•     •     •

At the risk of stating the obvious, I’m not David Carr. And this is not the New York Times. I suppose my inquiries are easily ignored—coming, as they do, from an “outsider” whose blog has just 330-some subscribers. On the other hand—and not to put too fine a point on it—I’m asking the kinds of questions these people should be asked, by their colleagues, the press, and, in the case of the non-profits like the American Bird Conservancy, their donors.

That seems to be changing though—which means these folks had better get to work on better responses (or, as Carr suggests, put the nut-cup on). In the meantime, the fact that they refuse to engage speaks volumes.

Literature Cited
1.  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

2. 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

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

4. Gibson, A.K., et al., “Polyparasitism Is Associated with Increased Disease Severity in Toxoplasma gondii-Infected Marine Sentinel Species.” PLoS Neglected Tropical Diseases. 2011. 5(5): p. e1142. http://dx.doi.org/10.1371%2Fjournal.pntd.0001142

5. Hide, G., et al., “Evidence for high levels of vertical transmission in Toxoplasma gondii.” Parasitology. 2009. 136(Special Issue 14): p. 1877-1885. http://dx.doi.org/10.1017/S0031182009990941

6. Prestrud, K.W., et al., “Serosurvey for Toxoplasma gondii in arctic foxes and possible sources of infection in the high Arctic of Svalbard.” Veterinary Parasitology. 2007. 150(1–2): p. 6–12. http://www.sciencedirect.com/science/article/B6TD7-4PYR4P2-2/2/fcc91fcf1d1426cd1b750bd3840bdb31

7. Oksanen, A., et al., “Prevalence of Antibodies Against Toxoplasma gondii in Polar Bears (Ursus maritimus) From Svalbard and East Greenland.” Journal of Parasitology. 2009. 95(1): p. 89–94. http://dx.doi.org/10.1645/GE-1590.1

8. Sroka, J., Szymańska, J., and Wójcik-Fatla, A., “The occurrence of Toxoplasma gondii and Borrelia burgdorferi sensu lato in Ixodes ricinus ticks from eastern Poland with the use of PCR.” Annals of Agricultural and Environmental Medicine. 2009. 16(2): p. 313–319.

9. n.a., Draft Environmental Assessment: Florida Keys National Wildlife Refuges Complex Integrated Predator Management Plan. 2011, U.S. Fish & Wildlife Service: Big Pine Key, FL. http://www.fws.gov/nationalkeydeer/predatormgmt.html

10. n.a., “Around the Refuge System: Florida and Arizona.” Refuge Update. 2010. 2. p. 17.

11. Forys, E.A. and Humphrey, S.R., “Use of Population Viability Analysis to Evaluate Management Options for the Endangered Lower Keys Marsh Rabbit.” The Journal of Wildlife Management. 1999. 63(1): p. 251–260. http://www.jstor.org/stable/3802507

Loose Threads

OpossumNorth American Opossum with winter coat. Photo courtesy of Wikimedia Commons and Cody Pope.

A study published last month in the online open-access journal PLoS Neglected Tropical Diseases suggests a new twist in the relationship between free-roaming cats, Toxoplasma gondii, and toxoplasmosis infections in marine mammals.

“The most remarkable finding of our study,” notes co-author Dr. Michael E. Grigg in a press release from the National Institutes of Health “was the exacerbating role that [Sarcocystis] neurona appears to play in causing more severe disease symptoms in those animals that are also infected with T. gondii.” What I found most remarkable, though, was the straightforward relationship between infections in land mammals and infected marine mammals implied in Grigg’s comments:

“Identifying the threads that connect these parasites from wild and domestic land animals to marine mammals helps us to see ways that those threads might be cut… by, for example, managing feral cat and opossum populations, reducing run-off from urban areas near the coast, monitoring water quality and controlling erosion to prevent parasites from entering the marine food chain.”

The Wildlife Society’s Michael Hutchins used the opportunity to once again call for the “control” of feral cats, which, he argues are “a menace to our native wildlife.” According to Hutchins, the study by Grigg (who serves as Chief of the National Institute of Allergy and Infectious Diseases’ Molecular Parasitology Unit) and his colleagues “is yet another demonstration that Trap-Neuter-Release (TNR) management of feral house cats must be stopped if we value our native wildlife.”

But, of course, the threads that make up the ecological “fabric” are interwoven with many others. Cut even one of them, as Grigg suggests, and the whole thing can begin to unravel.

Which is what surprised me about Grigg’s narrow focus on cats (considered the definitive host for T. gondii) and opossums (considered the definitive host of S. neurona), neither of which was mentioned in the paper itself.

Toxoplasma gondii
Cats pass the mature, infective form of T. gondii in their feces—a process called “shedding oocysts.” T. gondii infection, or toxoplasmosis, in humans can be traced to “ingestion of oocyst-contaminated soil and water, from tissue cysts in undercooked meat, by transplantation, blood transfusion, laboratory accidents, or congenitally.” [1]

Numerous studies have suggested a link between toxoplasmosis in marine life and freshwater run-off. In contrast to the “stress placed on the importance of the cat in the scientific literature,” [2] however, several studies have challenged the importance of environmental contamination in the transmission of T. gondii.

In the Absence of Cats
Researchers at the University of Salford’s Centre for Parasitology and Disease Research, for instance, observed high levels (e.g., 75 percent) of congenital transmission of T. gondii in a “wild population of mice,” leading them to conclude “that this phenomenon might be more widespread than previously thought.” [2] Another team of researchers from the same lab, citing studies of T. gondii infections in sheep, also make a compelling argument that congenital transmission “may be more important than previously considered.” [3]

And then there are the studies in the Arctic.

Among the “arctic foxes (n=594), Svalbard reindeer (n=390), sibling voles (n=361), walruses (n=17), kittiwakes (n=58), barnacle geese (n=149), and glaucous gulls (n=27),” tested, Prestrud et al. found T. gondii only in the arctic foxes (257, or 43 percent), geese (11, or 7 percent), and walruses (1, or 6 percent). [4] The fact that these researchers found no T. gondii-infected reindeer or sibling voles “indicates that infection by oocysts is not an important mode of transmission on Svalbard.” [4] In the end, Prestrud et al. suggest:

“…T. gondii most likely is brought to Svalbard by migratory birds that become infected in temperate agricultural areas in the winter. However, marine sources of infection may exist. The high seroprevalence of T. gondii in the arctic fox population on Svalbard may be due to: (1) infection from migratory bird species through predation; (2) vertical transmission; and (3) tissue cyst transmission within the Svalbard ecosystem through scavenging and cannibalism. Together, these transmission routes cause a surprisingly high seroprevalence of T. gondii in a top predator living in an ecosystem with very few cats.” [4]

A study of polar bears provides further evidence: “It would… be inconceivable to assume that the few cats would play a major role in the epidemiology of T. gondii in the vast high Arctic. This is apparently the case in East Greenland as well.” [5]

Ticks and Tick-bites
In a paper published in 2009, Polish researchers proposed yet another possibility. The “high incidence of T. gondii found, among others, in free-living ruminants,” write Sroka et al., “suggests a possibility of other, so far unknown, paths of transmission of this protozoan.”

“Due to the fact that they are widespread, and tick-bites occur frequently both in humans and in animals, ticks might play an important role in toxoplasmosis transmission.” [6]

Sarcocystis neurona and Opossums
The links between opossums and S. neurona infections, too, are not quite as straightforward as Grigg’s comment suggests. Researchers were surprised to find S. neurona in central Wyoming, for example—“outside the known range of the opossum.” [7]

“Finding antibodies to S. neurona… in at least 18 horses native to Wyoming is unexpected and unexplained. Opossums are not known to occur in central Wyoming, and there has not been any confirmed case of [equine protozoal myeloencephalitis] from horses native to Wyoming.” [7]

Their findings, write Dubey et al., “suggest that another definitive host may be involved or that the parasite shares antigens with another protozoan.” [7]

Conspicuously Absent
Grigg and his colleagues make no reference to these studies, nor do they acknowledge the alternative transmission routes suggested therein. To be clear, though, the paper focuses mostly on infection rates; it’s the press release that refers to cats and opossums as the ultimate source of infection.

(If all of this sounds familiar, it may be because I referred to many of the same studies in my response last month to a press release about a study of T. gondii-infected mammals in a “natural area in central Illinois” by Shannon Fredebaugh and Nohra Mateus-Pinilla.)

Stray Threads
Grigg and his colleagues found infection rates among mammals living in the inland waters of Washington, Oregon, and southern British Columbia were no greater than in those found along the outer coast, as illustrated in the figure below (blue dots indicating inland infection, red dots indicating infection among outer coast individuals).

But if environmental contamination plays such a critical role, shouldn’t that be reflected in higher infection rates inland (nearer, presumably, to greater concentrations of contaminated soil)?

Perhaps the most puzzling of their findings, though, is this: “T. gondii infections peaked in 2007 then declined relative to S. neurona” (as illustrated in the bar chart below).

Again, if environmental contamination is the culprit, does this mean that the population of free-roaming cats in the area also peaked around 2007? Could this, in fact, be empirical evidence of the positive impact of TNR? (At last, something for Hutchins to blog about!)

Obviously, there’s not enough evidence here to make that leap. Still, the data challenge assertions by the American Bird Conservancy that the feral cat population continues to rise—as well as the conventional wisdom about the presumed cause of T. Gondii-infected marine mammals, articulated most recently by David Jessup and Melissa Miller: “the science points to cats.” [8]

And finally, let’s say we were able to remove all of the cats and opossums from the environment. Setting aside for the moment the numerous hurdles (e.g., ethical, economic, etc.) involved, what impact could we expect in terms of T. gondii and/or S. neurona infections in marine mammals? Or in rodents, whose populations would surely skyrocket?

I’m skeptical that the benefits would be all that great. Skeptical, too, that we could predict with much accuracy the actual outcomes (to say nothing of the unintended consequences).

As for what Grigg thinks, he’s yet to respond to my e-mail inquiries on the subject.

Literature Cited
1. Elmore, S.A., et al., “Toxoplasma gondii: epidemiology, feline clinical aspects, and prevention.” Trends in Parasitology. 2010. 26(4): p. 190–196. http://www.sciencedirect.com/science/article/B6W7G-4YHFWNM-1/2/2a468a936eb06649fde0463deae4e92f

2. Marshall, P.A., et al., “Detection of high levels of congenital transmission of Toxoplasma gondii in natural urban populations of Mus domesticus.” Parasitology. 2004. 128(01): p. 39–42. http://dx.doi.org/10.1017/S0031182003004189

3. Hide, G., et al., “Evidence for high levels of vertical transmission in Toxoplasma gondii.” Parasitology. 2009. 136(Special Issue 14): p. 1877-1885. http://dx.doi.org/10.1017/S0031182009990941

4. Prestrud, K.W., et al., “Serosurvey for Toxoplasma gondii in arctic foxes and possible sources of infection in the high Arctic of Svalbard.” Veterinary Parasitology. 2007. 150(1-2): p. 6–12. http://www.sciencedirect.com/science/article/B6TD7-4PYR4P2-2/2/fcc91fcf1d1426cd1b750bd3840bdb31

5. Oksanen, A., et al., “Prevalence of Antibodies Against Toxoplasma gondii in Polar Bears (Ursus maritimus) From Svalbard and East Greenland.” Journal of Parasitology. 2009. 95(1): p. 89–94. http://dx.doi.org/10.1645/GE-1590.1

6. Sroka, J., Szymańska, J., and Wójcik-Fatla, A., “The occurrence of Toxoplasma gondii and Borrelia burgdorferi sensu lato in Ixodes ricinus ticks from eastern Poland with the use of PCR.” Annals of Agricultural and Environmental Medicine. 2009. 16(2): p. 313–319.

7. Dubey, J.P., et al., “Prevalence of Antibodies to Neospora caninum, Sarcocystis neurona, and Toxoplasma gondii in Wild Horses from Central Wyoming.” Journal of Parasitology. 2003. 89(4): p. 716–720. http://dx.doi.org/10.1645/GE-66R

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

Spoiler Alert

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).

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).

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.

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. 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

Close Enough?

Among the findings of a recent study:

Five of 18 cats trapped “between the spring and fall of 2008 and 2009” in central Illinois’ 1,500-acre Robert Allerton Park tested positive for Toxoplasma gondii antibodies. Five of the seropositive cats were trapped at the same site; there, one white-footed mouse (of 21 trapped) also tested positive, and a gray squirrel tested negative. The site where the sixth seropositive cat was trapped revealed similar results among the “small home range” (SHR) mammals found there: one of 34 white-footed mice was seropositive; a fox squirrel was negative.

All of which means… what, exactly?

Although there were five times as many “infected” cats at the first site, infection rates among SHR mammals were only about one-and-a-half times as high as those at the second site. Put another way: given the infection rate among SHR mammals at the second site, one would have expected three seropositive SHR mammals at the first site.

In fact, a press release put out last week put a very different spin on Shannon Fredebaugh’s thesis work (downloadable PDF):

One third of the cats sampled were infected with T gondii, as were significant numbers of the wild animals found at every site. Animals that inhabit or range over territories of 247 acres (100 hectares) or more, such as raccoons and opossums, were more likely to be infected than those with smaller ranges.

But these animals “could have acquired T. gondii infection somewhere outside of the park,” said Nohra Mateus-Pinilla, a wildlife veterinary epidemiologist at the University of Illinois Prairie Research Institute and leader of the study. Animals with smaller home ranges likely picked up the infection close to where they were trapped, she said. This makes these animals good sentinels of disease in a natural area. “The small animals are screening the environment for us,” she said. “So when we sample one of those animals, we are really sampling their lifestyle.”

The absence of bobcats in the park combined with the occurrence of domestic cats and T. gondii infection in wildlife that inhabit small territories strongly suggest that feral, free-ranging or abandoned house cats are the source of the infection, Mateus-Pinilla said. Cats are vital for the survival of the parasite, and so they are—either directly or indirectly—spreading T. gondii to the wildlife in the park. “There’s no other option,” she said.

Well, “one third of the cats” certainly sounds more impressive than “six of 18.” And “significant numbers of the wild animals found at every site” had an undeniable allure to it—though, in fact, the statement applies only to the park’s “large home range” (LHR) mammals (mostly raccoons and opossums).

Far more troubling, though, is the alleged connection between cats, T. gondii, and infected SHR mammals.

Environmental Contamination
“If one infected cat defecates there, any area can become infected,” Fredebaugh said in the press release. “It just takes one cat to bring disease to an area.”

But, as Fredebaugh points out, “environmental detection of oocysts is difficult and was not evaluated in this study.” [1] She simply assumes a causal link between “infected” cats and environmental contamination: more seropositive cats means more contaminated soil.

In fact, Fredebaugh goes further, assuming that the mere presence of cats—seropositive or not—is the key factor in SHR infection rates. In addition to trapping data, she uses data from scent stations and motion detection cameras (which proved largely ineffective, capturing photos of just four cats over the course of the research) to designate each of the eight sites as either high or low “cat occurrence,” as indicated in the following table (please forgive the tiny type):

Table: Shannon Fredebaugh's Thesis

Fredebaugh acknowledges that “scent stations should only be used to identify trends in animal populations and as a supplemental tool in conjunction with other population estimates,” [1] thereby raising serious questions about their use in her study. (She’s not interested in trends, her scent station and trapping data correlate quite poorly, and her use of scent station data is hardly “supplemental.”)

But back to the environmental contamination.

Cats (both domestic and wild) are T. gondii’s definitive host—the animal in which the parasite reproduces sexually. Cats pass the mature, infective form of T. gondii in their feces—a process called “shedding oocysts.”

Although oocysts can survive in soil for up to 18 months, and are resistant to disinfectants, cats typically “shed oocysts only once in their life.” [see discussion in 2] Indeed, according to Dubey and Jones, “Most cats seroconvert after they have shed oocysts. Thus, it is a reasonable assumption that most seropositive cats have already shed oocysts.” [2]

So, who’s to say that the “infected” cats Fredebaugh trapped shed oocysts in the area where they were found? Indeed, we don’t even know that these cats shed oocysts in the park. It’s been suggested (based on a small sample of cats monitored closely from 1974 to 1977) that home ranges of unsterilized feral females can exceed 500 acres, while those of unsterilized feral males may approach 2,500 acres. (Even house-based males, which were also unsterilized, had large home ranges: 865–939 acres.) [3]

What’s more, Fredebaugh points out that, given their “relatively good physical condition,” some of these cats might have been “recently abandoned at RAP.” [1] In which case, they wouldn’t have been “contributing” any oocysts to the park’s soil—assuming they were seropositive to begin with.

Odds Ratios
Fredebaugh expresses her results using odds ratios, a measure easy enough to calculate but rather difficult to grasp intuitively (especially for those of us, myself included, unfamiliar with the measure). A page on the Children’s Mercy Hospital (Kansas City, MO) Website explains odd ratios this way:

“An odds ratio of 1 implies that the event is equally likely in both groups. An odds ratio greater than one implies that the event is more likely in the first group. An odds ratio less than one implies that the event is less likely in the first group.”

(Some examples are discussed in detail here.)

It seems to me that, in this case at least, odds ratios obscure more than they reveal. When Fredebaugh reports “a significant difference in the seroprevalence of T. gondii for SHR mammals at sites with a high frequency of cat occurrence,” we know nothing of sample size or the overall fit of the data (which, ranges from pretty good—for LHR mammals—to pretty lousy—for SHR mammals).

A simple x-y graph illustrates this point:

Chart: Shannon Fredebaugh's Thesis

By (mis?)representing the data in odds ratios, Fredebaugh suggests a connection that’s not actually supported by her research findings.

That said, she’s is hardly the first to imply causation where nothing more than correlation has been demonstrated (and, again, even that is dicey). In “The Impact of Free Ranging Cats,” a special section of the Spring Issue of The Wildlife Professional, for example, David Jessup and Melissa Miller argue that “the science points to cats,” but provide little more than “proximity” and “sheer numbers” to support their claim that “outdoor pet and feral domestic cats may be the most important source of T. gondii oocysts in near-shore marine waters.” [4]

(No?) Other Options
The fact that the researchers are so certain of their conclusions—that the only explanation for T. gondii in Robert Allerton Park is the presence of cats—is telling. I can’t help but think that they knew going in what they would find (a perception reinforced by what’s included in, and omitted from, Fredebaugh’s literature review, as described below).

In fact, Mateus-Pinilla’s comment—“There’s no other option.”—is challenged by several recent studies.

“Among white-footed mice,” writes Fredebaugh, “I found a 6 percent seroprevalence of T. gondii antibodies, which was high, compared to other studies… Mice have a short life span, thus the findings that mice, including some juveniles, were seropositive implies an active infection and recent T. gondii contamination in RAP.” [1]

Actually, researchers at the University of Salford’s Centre for Parasitology and Disease Research found an overall prevalence of 59 percent among the “200 mice… trapped from within houses in the Cheetham Hill area of Manchester.” [5] More important, they observed “high levels of congenital transmission… with 75 percent of female mice transmitting parasites to foetuses prior to birth” (emphasis added), leading them to conclude:

“These high levels of congenital transmission in this wild population of mice, taken together with other recent data on congenital transmission in sheep, suggests that this phenomenon might be more widespread than previously thought.” [5]

Fredebaugh, by contrast, mentions congenital transmission only in passing.

In another paper, researchers from the Centre for Parasitology and Disease Research challenge the conventional wisdom surrounding the transmission of T. gondii (note: I’ve removed several in-text citations for the sake of readability):

“The life cycle is well understood and three principal routes are recognised: ingestion of infective oocysts shed by the cat, consumption of undercooked meat containing Toxoplasma cysts and congenital transmission. Traditionally, the main route of infection is considered to be infection by oocysts deposited in faeces by the definitive host, the cat. This would imply that a high degree of contact with cats would be required to explain the very high prevalences found in many animal and human populations. Toxoplasma gondii has been reported in a very wide range of species. However, this also includes some species that would not normally come into contact with cats.” [6]

“Congenital transmission,” suggest Hide et al., “offers another possible mode of parasite transmission in the absence of cats.” [6]

“One way of determining the importance of transmission routes is to investigate transmission in a system where one of the routes of transmission is absent or minimal. For example, the carnivorous route could be excluded as a source of transmission in a herbivorous species such as sheep.” [6]

On the basis of multiple studies (see [7] and [8] for details of the study with sheep), Hide and his colleagues make a compelling argument that congenital transmission “may be more important than previously considered.” [6]

Researchers working in “the remote, virtually cat-free, high arctic islands of Svalbard” (the northern-most part of Norway) [9] came to similar conclusions. Among the “arctic foxes (n  = 594), Svalbard reindeer (n  = 390), sibling voles (n  = 361), walruses (n  = 17), kittiwakes (n  = 58), barnacle geese (n  = 149), and glaucous gulls (n  = 27),” tested, Prestrud et al. found T. gondii only in the arctic foxes (257, or 43 percent), geese (11, or 7 percent), and walruses (1, or 6 percent). [10]

“The finding of no seropositive reindeer or sibling voles,” they argue, “indicates that infection by oocysts is not an important mode of transmission on Svalbard.” [10] (Also of interest is their suggestion that the seropositive walrus demonstrates “that T. gondii is present in the marine food chain.” [10])

So where does the T. gondii come from?

“…we suggest that T. gondii most likely is brought to Svalbard by migratory birds that become infected in temperate agricultural areas in the winter. However, marine sources of infection may exist. The high seroprevalence of T. gondii in the arctic fox population on Svalbard may be due to: (1) infection from migratory bird species through predation; (2) vertical transmission; and (3) tissue cyst transmission within the Svalbard ecosystem through scavenging and cannibalism. Together, these transmission routes cause a surprisingly high seroprevalence of T. gondii in a top predator living in an ecosystem with very few cats.” [10]

A study of polar bears is further evidence that “other options” do indeed exist:

“In Svalbard cats are banned by the Norwegian authorities; however, a few cats may exist in Russian mining communities. Thus, the possibility of cats as a source of infection for polar bears cannot totally be excluded. Nonetheless, the existing cat population is very limited and local, and the proportion of seropositive polar bears is rather high, indicating that polar bears are commonly infected with T. gondii. It would, therefore, be inconceivable to assume that the few cats would play a major role in the epidemiology of T. gondii in the vast high Arctic. This is apparently the case in East Greenland as well.” [11]

As with the single seropositive walrus discussed above, the results of the polar bear study indicates “that there might be marine sources of T. gondii in the region.” [9]

And finally, in a paper published in 2009, Polish researchers proposed yet another possibility. The “high incidence of T. gondii found, among others, in free-living ruminants,” write Sroka et al., “suggests a possibility of other, so far unknown, paths of transmission of this protozoan.”

“Due to the fact that they are widespread, and tick-bites occur frequently both in humans and in animals, ticks might play an important role in toxoplasmosis transmission.” [12] (Note: the authors acknowledge both support for, and differing opinions about, the possibility of such a pathway.)

Fredebaugh mentions none of this work in her thesis; none of the author’s names appear in her lengthy list of references (which, to most people, probably appears comprehensive). And still, both she and Mateus-Pinilla (who chaired Fredebaugh’s thesis advisory committee) are committed to the proposition that, as Jessup and Miller suggest, “the science points to cats.”

Greater (Mis)Understanding
Fredebaugh concludes her thesis by suggesting that her results:

“provide a greater understanding of how feral cats and wildlife utilize natural areas in a highly fragmented landscape and how feral cat land use may impact wildlife parasite prevalence both directly and indirectly. With this information, I more clearly understand the association between wildlife and feral cats and can suggest better control strategies for feral cat populations. Using wildlife with small spatial scale habitat use as sentinels of parasite presence in the environment, I can gain a better understanding of the epidemiologic impact of T. gondii in different urban and rural settings to prevent human and wildlife infection. Further collaborative research is needed to determine the most effective management strategy for feral cat populations in natural areas and to evaluate the direct relationship between feral cats and their impacts on wildlife.” [1]

At the risk of being overly critical, I’m suggesting that Fredebaugh’s work has not only failed to clarify our understanding of feral cats, wildlife, and the transmission of T. gondii, but has—due to its problematic methodology and incomplete literature review—actually made matters worse (especially with regard to possible “control strategies”).

•     •     •

Not surprisingly, The Wildlife Society’s CEO/Executive Director Michael Hutchins immediately endorsed the study (his summary conveniently omits the small sample size involved, the inverse relationship between “infected” cats and “infected” SHR mammals, and several other important aspects of the research) and its misguided conclusions, pleading:

“How many more peer reviewed studies do we need to convince leaders to change the way that we are currently dealing with the feral cat population explosion in this country?”

I don’t want to suggest that Hutchins and I are on the same page here, but omit the word explosion, and that’s pretty much the same question I’ve been asking for a while now.

Literature Cited
1. Fredebaugh, S.L., Habitat Overlap and Seroprevalence of Toxoplasma Gondii in Wildlife and Feral Cats in a Natural Area. 2010, University of Illinois at Urbana-Champaign: Urbana-Champaign, IL. p. 88. http://www.ideals.illinois.edu/bitstream/handle/2142/16185/1_Fredebaugh_Shannon.pdf?sequence=6

2. 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

3. Liberg, O., “Home range and territoriality in free-ranging house cats.” Acta Zoologica Fennica. 1984. 171: p. 283–285.

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

5. Marshall, P.A., et al., “Detection of high levels of congenital transmission of Toxoplasma gondii in natural urban populations of Mus domesticus.” Parasitology. 2004. 128(01): p. 39–42. http://dx.doi.org/10.1017/S0031182003004189

6. Hide, G., et al., “Evidence for high levels of vertical transmission in Toxoplasma gondii.” Parasitology. 2009. 136(Special Issue 14): p. 1877-1885. http://dx.doi.org/10.1017/S0031182009990941

7. Morley, E.K., et al., “Significant familial differences in the frequency of abortion and Toxoplasma gondii infection within a flock of Charollais sheep.” Parasitology. 2005. 131(02): p. 181–185. http://dx.doi.org/10.1017/S0031182005007614

8. Morley, E.K., et al., “Evidence that primary infection of Charollais sheep with Toxoplasma gondii may not prevent foetal infection and abortion in subsequent lambings.” Parasitology. 2008. 135(02): p. 169–173. http://dx.doi.org/10.1017/S0031182007003721

9. Prestrud, K.W., et al., “Direct high-resolution genotyping of Toxoplasma gondii in arctic foxes (Vulpes lagopus) in the remote arctic Svalbard archipelago reveals widespread clonal Type II lineage.” Veterinary Parasitology. 2008. 158(1-2): p. 121–128. http://www.sciencedirect.com/science/article/B6TD7-4TDK6Y8-2/2/1e5b02861f7a0c81f2277f65f42e6be9

10. Prestrud, K.W., et al., “Serosurvey for Toxoplasma gondii in arctic foxes and possible sources of infection in the high Arctic of Svalbard.” Veterinary Parasitology. 2007. 150(1-2): p. 6–12. http://www.sciencedirect.com/science/article/B6TD7-4PYR4P2-2/2/fcc91fcf1d1426cd1b750bd3840bdb31

11. Oksanen, A., et al., “Prevalence of Antibodies Against Toxoplasma gondii in Polar Bears (Ursus maritimus) From Svalbard and East Greenland.” Journal of Parasitology. 2009. 95(1): p. 89–94. http://dx.doi.org/10.1645/GE-1590.1

12. Sroka, J., Szymańska, J., and Wójcik-Fatla, A., “The occurrence of Toxoplasma gondii and Borrelia burgdorferi sensu lato in Ixodes ricinus ticks from eastern Poland with the use of PCR.” Annals of Agricultural and Environmental Medicine. 2009. 16(2): p. 313–319.

It’s Not the Media, It’s the Message

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.”

  • 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.

“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.”

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
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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

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. 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.

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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

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

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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

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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

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

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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

A House Deluded

On February 25th, the Utah House of Representatives voted rather decisively—44 to 28—in favor of HB 210, which would amend the state’s animal cruelty laws. Whether or not the representatives knew what they were voting for, however, is anybody’s guess.

Listening to the floor debate, one gets the impression there were two—maybe three—different bills up for discussion. Not that House members got any help from sponsor Curtis Oda (R). Indeed, Oda’s rambling, disjointed presentation only muddied the waters further.

Among the bill’s provisions is an exemption for animal cruelty in cases where the individual responsible for harming or killing an animal acted reasonably, in the protection of people or property. Also included—and the source of the greatest controversy—is an allowance for “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.”

This Is Not About Cats
Referring to the bad press HB 210 has received over the past few weeks (including a stinging satire on The Colbert Report, which was widely circulated on the Web), Oda was, not surprisingly, defensive.

“It wasn’t about cats; it’s about all animals that are feral—including cats, dogs, pigeons, pigs, whatever it might be… But the cat community has made it a cat issue, so let’s talk cats.”

And talk cats he did.

“Let’s get into some of the other reasons why we need some of this… The U.S. Fish and Wildlife Service—and because it was made into a cat issue, I’m using cats—cites that cats and other introduced predators are responsible for much of the migratory bird loss. Domestic and feral may kill hundreds of millions of songbirds and other avian species every year, roughly 39 million birds annually. They’re opportunistic hunters, taking any small animal available—pheasants, native quail, grouse, turkeys, waterfowl, and endangered piping plovers. Most of these birds are protected species.”

That 39 million figure, of course, comes from the notorious Wisconsin Study, and represents Coleman and Temple’s “intermediate… estimate of the number of birds killed annually by rural cats in Wisconsin.” [1] Nothing more than a “best guess,” as the authors call it, and one based entirely on the predation of a single cat in rural Virginia. [2, 3]

It’s a figure commonly found in U.S. Fish and Wildlife Service (USFWS) publications, [4, 5] and on their Website. (Oda’s not the first one to mistake this for an estimate of predation across the country, however; Frank Gill made the same error in his book Ornithology. [6])

Oda’s choice of bird species surely raised a few eyebrows—at least among those who were paying attention. First of all, a number of the birds are hunted in Utah—which would seem to complicate the predation issue significantly (though, of course, hunters are paying for the “privilege” of killing wildlife).

And those “endangered piping plovers” (technically, listed as “Near Threatened”)? According to the Cornell Lab of Ornithology Website, this “small pale shorebird of open sandy beaches and alkali flats…[apparently, Utah’s salt flats don’t count] is found along the Atlantic and Gulf coasts, as well as inland in the northern Great Plains.”

Another obvious blunder: Oda would have us believe that cats are both opportunistic hunters (which they are) but that they also target rare and endangered species. (But again, Oda’s not alone: USFWS made a similar argument in their recent Florida Keys National Wildlife Refuges Complex Integrated Predator Management Plan/Draft Environmental Assessment.

Economic Impact
Once Oda brought up Wisconsin, it seemed almost inevitable that Nebraska, too, would creep into the debate. It didn’t take long.

“The Audubon magazine recently cited a new peer-reviewed paper by University of Nebraska–Lincoln—researchers concluding that feral cats—domestic that live outdoors and are ownerless—in other words, feral—account for $17 billion—that’s billion—in economic loss from predation on birds in the U.S. every year.”

That $17 million dollar figure (which, apparently, was just too good for the National Audubon Society, American Bird Conservancy, and others to pass up) is based on some very dubious math (indeed, the paper notes that birders spend just $0.40 for each bird seen, whereas hunters spend $216 for each bird shot, suggesting, it seems, that dead birds are far more valuable than live birds—a point NAS and ABC, of course, ignored entirely).

The origins of the figure can be traced to two papers by Cornell’s David Pimentel and his colleagues, [7, 8] in which the authors estimate “economic damages associated with alien invasive species.” [8]

Referring to this work, Hoagland and Jin, resource economists at the Marine Policy Center, Woods Hole Oceanographic Institution, (using the case of the European green crab to make their point) warn: “There are many reasons to be concerned about the use of these estimates for policymaking.” [9] Among their concerns, are the use of potential rather than actual impacts, and the validity of the underlying science—as well as the overall lack of rigor involved in developing such estimates.

“Heretofore, estimates of the economic losses arising from invasive species have been far too casual. Unfounded calculations of economic damages lacking a solid demonstration of ecological effects are misleading and wasteful.” [9]

Predation Estimates
Oda then tried to put the predation into context:

“In Utah alone, if we assume a million households, you can estimate around a third of them have cats—that’s 333,333. If we just add a feral population of at least that many, making it two-thirds of a million—if each cat killed just three birds per year, you can see that the predation is around two million each year.”

Three birds/year is more conservative than what’s used for many back-of-the-envelope estimates, but that doesn’t excuse the flaws in Oda’s calculation—beginning with his suggestion that the number of feral cats in the state equals the number of pet cats. Where’s the evidence?

He’s also assuming that all cats hunt. However, about two-thirds of pet cats don’t even go outside. [10–12]

And then, of course, there’s the issue of impact. Even if Oda’s right about the two million birds, that says nothing about the impact on their populations. Are the birds common? Rare? Healthy? Unhealthy? Etc.

Referring to “Cats and Wildlife: A Conservation Dilemma,” another of the Wisconsin Study papers, [13] Oda continues:

“Nationwide, cats probably kill over a billion mammals and hundreds of millions of birds each year. Worldwide, cats may have been involved in the extinction of more bird species than any other cause except by habitat destruction.”

Again, no mention of impact. And, no mention of where the vast majority of those extinctions took place.  According to Gill’s Ornithology:

“Most (119, or 92 percent) of the 129 bird species that have become officially extinct in the past 500 years are island species. Roughly half of these species were exterminated by introduced predators and diseases. The rest were driven to extinction by direct human exploitation and habitat destruction.” [6]

However isolated Utah may seem at times—politically, socially, and culturally—the state is not an actual island.

Trap-Neuter-Return
For an assessment of TNR, Oda turns not to Alley Cat Allies or to the No More Homeless Pets in Utah program, but to David Jessup, Senior Wildlife Veterinarian with the California Department of Fish and Game:

“David Jessup, a Doctor of Veterinary Medicine, has written that trap, neuter, and release programs are not working as well as it has been touted. I’ve got packets here talking about that. If anybody wants to see it, they’re welcome to that.”

In fact, Jessup offers little to support his own sweeping claim that, “in most locations where TNR has been tried, it fails to substantially or quickly reduce cat numbers and almost never eliminates feral cat populations” [14] Instead, he refers to a paper by Linda Winter, [15] former director of ABC’s Cats Indoors! campaign—and prolific source of misinformation on the subject of TNR.

Oda continues:

“Releasing feral cats back into the wild is actually an unnatural act. They are unnatural predators that compete [for] food with eagles, hawks, owls, ferrets, etc.”

This last point, it would seem, is a reference to the often-cited work of William George, who suggested that “cats inevitably compete for prey with many of our declining raptors, and therein may lie a serious problem.” [16] It turns out, though, that George’s concerns were largely unfounded, as I’ve discussed previously.

No wonder Oda turned to Jessup and Winter for a TNR primer—the man simply doesn’t have a clue:

“Citizens that want to help are often met with expenses and inconveniences that deter them. Many who monitor TNR colonies are not managing them correctly. I had one lady who said she had more than 100 cats that she had saved with TNR, but kept getting new cats almost weekly. She’d been feeding them more than what they could do on their own, thereby attracting new cats.”

I rather doubt that making it legal to shoot at feral cats will somehow make caretakers’ lives easier. And why, if Oda thinks regular citizens are unable to properly manage a colony of feral cats, is he so sure they’ll be able to properly distinguish a feral cat from a pet in the event they want to shoot it?

Oda’s complaint about feeding feral cats—and the idea that this attracts additional cats—is a common one. Cats are remarkably resourceful, and where there are people, there is food. Better to have them part of a managed colony, where they are sterilized—and often adopted, too—than to be under the radar.

The same argument can be made for the alleged relationship between TNR and the dumping of cats. It’s difficult to imagine that the presence or absence of a nearby TNR program would affect a person’s decision to abandon his/her pet cat(s). (If any studies had demonstrated such a connection, TNR opponents would surely cite them.) And, under the circumstances, isn’t it better that they be “enrolled” in a TNR program than the alternative?

“Releasing is also unfair to the rest of the neighborhood,” argued Oda, “who’s adversely affected.”

“It doesn’t affect just the person monitoring. But the problem is much bigger than TNR only. An unspayed female cat can have up to three litters per year, with an average of five kittens per litter, so as you can see, the problem grows exponentially.”

While unrestricted populations will grow exponentially, Oda’s numbers are ridiculous—probably the foundation for the widely debunked 420,000-cats-in-seven-years-myth.

Still think HB 210 isn’t about cats?

A Little Something for Everybody
At this point, Oda’s presentation moves beyond the bogus science and tired, baseless complaints—and pretty well comes off the rails entirely.

“This bill does not replace TNR, but it’s supposed to work potentially in conjunction with TNR, but we need to make sure everybody uses those TNR programs properly. We do have a serious problem with irresponsible owners, and we can’t make it unreasonable for them to take their animals to shelters and animal control facilities… We need to make things a little bit easier for people to help, not just make it easier for them to—” [lost audio]

How open season on feral cats is “supposed to work potentially in conjunction with TNR” is a mystery—and one Oda didn’t have a chance to clear up. At this point, his colleagues give him just one more minute to wrap things up.

“We just need to make it easier for people to be able to do things the right way, instead of making it so ridiculously expensive and inconvenient—so that it’s easier for them to just take their animals and drop them off anywhere else, whether it be cats or dogs, or whatever it may be. Perhaps down the road we might have to have mandatory licensing for cats. We do that with dogs already and the problem with dogs has diminished substantially.”

Huh?

Are we still talking about the same bill here? HB 210 does nothing at all to address dumping, intake policies at shelters, or licensing. The confusion only worsened as several representatives supporting the bill took to the House floor to make their positions known.

Supporters
Rep. Fred Cox
(R), who helped revise the bill, suggested that HB 210 offers a means of controlling the population of feral cats—a complement to TNR programs:

“We spent quite a bit of time reviewing with proposed amendments… We did have the opportunity of listening to a number of individuals speak for and on behalf of various options… You have to decide whether or not it’s a good idea for individuals to purposely release certain animals—sometimes in large quantities into the wild that were not originally designed to be here. There are certain parts of the world that have had problems with this area, and in some cases, we have problems now. This provides us an option. We still have other options that are available—with trap, neuter, and release—those are still on the table. This does not prohibit those methods to be used, but does allow another method to be used.”

For Rep. Lee Perry (R), HB 210 offers a humane approach for dealing with abandoned pets:

“I represent a lot of rural farmers and ranchers, and this bill is critical to them. I can’t have a farmer or rancher going to jail or to prison because they take care of a feral cat or a feral dog that is on their ranch or their farm, that somebody inhumanely took out and dumped out in the middle of western Box Elder County or in western Cache County. When the people go out there and dump their animals, thinking they’re being humane and putting them… out into the wild or onto somebody’s farm, they’re actually harming those animals more than what these farmers or ranchers would be doing in basically being humane, and putting them out of their misery at that point. Because these animals are eventually going to starve to death, in some cases, and die. They’re left in the cold, in the elements. These are usually animals that are meant to be raised in a house, and in a controlled environment. Because of that, I support this substitute bill, and I would ask that the body would support it as well.”

Easily the most interesting account, however, was that of Rep. Brad Galvez (R):

“I had an individual that lives just a few miles west of my home who was basically attacked by a cat—had a cat that scratched him on his hand, and he basically just flung it against the wall. This individual was charged with a third-degree felony.”

A search of several newspapers tells a very different story. Reese Ransom, 85, was actually charged with aggravated animal cruelty—a misdemeanor—when he severely injured a feral kitten. When Ransom picked up the kitten—one of a litter he and his wife had been feeding—to bring it inside:

“It went wild, like cats do,” he said. “It was scratching and biting. It was hanging from my hands with its teeth, so I just pitched it away to get rid of it. It hit the garage and knocked it out.” [17]

According to Ogden’s Standard–Examiner, Weber County Sheriff’s Deputy Bryce Weir witnessed the event. “Weir’s report said Weir got out of his patrol car and walked to the garage, noting the kitten was still alive, but barely moving.” [18]

The kitten was eventually euthanized.

The Animal Advocacy Alliance of Utah pushed for Ransom to be changed with a felony, but were unsuccessful.

But Galvez, who—don’t forget—lives just a few miles east of Ransom, completely misrepresents the facts of the case to his colleagues. There’s no telling whether or not his “interpretation” of events had any bearing on the eventual vote, but it raises questions about the man’s integrity.

Opponents of HB 210
HB 210 had its detractors as well. Among them, Rep. Marie Poulson (D):

“I am… the daughter of a rancher and a cattleman, but have another perspective on this. I realize the threat to cattle of these pests, or feral animals. But, in our particular case, we encourage the population of feral cats, as we have four granaries, and they were some of our best farm workers, and kept down the rodent population. My main problem with this bill is, there’s no designation between what’s considered a feral animal and your beloved house pet. And I think this bill gives license to kill in those areas. My other consideration here is that I have received so many letters from constituents upset by this bill that if I voted for it, I would be considered feral.”

Rep. David Litvack (D) wasn’t buying what Oda and his supporters were selling, especially when it comes to defining feral. “If a person knows that a particular animal is a pet of their neighbor,” explained Oda during his introductory comments, “it’s not feral. If it’s wearing a collar, it’s not feral. If there’s other signs it’s very friendly, obviously it’s not feral.”

Litvack was unmoved:

“I believe it is wrong for us, as a state, to move in the direction where we are having individuals make the decision, the determination on their own (1) what is feral, and (2) now, that they can shoot them, even if it’s only in an unincorporated county. Not a good policy, and, quite frankly, a bit of an embarrassment to the state of Utah.”

Referring specifically to Lines 153 and 154 of the amended bill (“…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.”), Rep. Brian King (D) took a similar stance:

“My concern is that we’re providing a loophole in the statute for individuals that want to use this as an opportunity to go out and satisfy [lost audio] they get pleasure from going out and just shooting what are now defined as feral animals just for the pleasure of killing the animal… This is a bill that’s been brought to us now, in its amended form, just today, and we haven’t had a chance to hear from the Humane Society, from other individuals or agencies that have an interest in this. And my concern is that, although I think there is undoubtedly a reasonable need for individuals under certain circumstances—in rural areas, especially—to control feral animal populations that are causing damage, I still have concerns—without more input from those who deal with this, and have really had a chance to think the language through—in voting it out of our body.”

“We spent quite a bit of time reviewing with proposed amendments,” countered Cox. “We did have the opportunity of listening to a number of individuals speak for and on behalf of various options.”

Cox offered no specifics about who was invited to the bargaining table. And it may not have made any difference anyhow—like Oda and Perry, Cox seems to think HB 210 is about feral cat management:

“You have to decide whether or not it’s a good idea for individuals to purposely release certain animals—sometimes in large quantities into the wild that were not originally designed to be here. There are certain parts of the world that have had problems with this area, and in some cases, we have problems now. This provides us an option. We still have other options that are available—with trap, neuter, and release—those are still on the table. This does not prohibit those methods to be used, but does allow another method to be used.”

Rep. Paul Ray (R) responded to King’s concern by comparing TNR to abandonment (an argument perhaps first articulated by Jessup, who refers to TNR as “trap, neuter, and reabandon” [14]):

“It’s against the law to abandon an animal… [TNR practitioners] abandon the animal again. So when we’re talking about getting the perfect language, I’m not sure we can do that because even under the current law we have right now, we have some discrepancies…”

Setting aside the TNR/abandonment issue for the moment, that’s quite a position to take for somebody whose job it is to craft legislation: What we’ve got now isn’t perfect, so why bother?

Oda’s response was no better. “Out in the rural areas,” he said, referring to the concerns about the ambiguity surrounding the term feral, “they know exactly what animals belong in the area, so that’s not even an issue.”

This, I’m sure, was no consolation to Litvack or King.

Shoot First, Ask Questions Later
If you missed the part where the bill’s supporters defend—or even explain—the need for Utahns to be able to shoot feral animals, you’re not alone. I’ve listened to the entire debate at least twice now and still don’t get it.

As Laura Nirenberg, legislative analyst for Best Friends’ Focus on Felines campaign, pointed out to me, the bill’s language already addresses many issues brought up in the debate.

Under HB 210, for example, the crime of animal cruelty requires that “the person’s conduct is not reasonable and necessary to protect: (1) the actor or another person from injury or death; or (2) property from damage or loss if the property is an animal; or other property that is $50 or more in value.” (The $50 threshold seems like too low a bar to me, but it was never mentioned during the floor debate.)

This, it seems, goes an awful long way toward protecting farmers and ranchers who are merely protecting their livestock. And the Reese Ransoms of the world, too. Moreover, there’s already a provision in Utah’s animal cruelty code exempting a “person who humanely destroys any apparently abandoned animal found on the person’s property” (which, strangely, never came up during the HB 210 debate).

Granted, the bill’s amended language does lessen its potential impact on feral cats by restricting “the humane shooting of an animal” to unincorporated areas “where hunting is not prohibited.” Hunting regulations must comply with Utah criminal code, which prohibits the “discharge any kind of dangerous weapon or firearm… without written permission to discharge the dangerous weapon from the owner or person in charge of the property within 600 feet of: a house, dwelling, or any other building; or any structure in which a domestic animal is kept or fed, including a barn, poultry yard, corral, feeding pen, or stockyard.”

Even so, the shooting provision of HB 210 strikes me as essentially indefensible. It’s simply an invitation for senseless cruelty. Representative Litvack is exactly right: “Not a good policy, and, quite frankly, a bit of an embarrassment to the state of Utah.”

•     •     •

It will be interesting to see what happens when HB 210 moves to the Utah Senate, where, just last week, TNR-friendly SB 57 was passed. Among its provisions:

“This bill… defines a sponsor of a cat colony as a person who actively traps cats in a colony for the purpose of sterilizing, vaccinating, and ear-tipping before returning the cat to its original location; exempts community cats from the three-day mandatory hold requirement; and allows a shelter that receives a feral cat to release it to a sponsor that operates a cat program.”

I encourage readers to listen to the HB 210 debate in its entirety, as it provides a fascinating glimpse of democracy in action—warts and all (including, for example, when Oda responds to the call for a vote with “Meow.”) The SMIL audio file is available here, and the required Real Audio application can be downloaded free here.

Literature Cited
1. 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

2. Coleman, J.S. and Temple, S.A., How Many Birds Do Cats Kill?, in Wildlife Control Technology. 1995. p. 44. http://www.wctech.com/WCT/index99.htm

3. 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. www.vacadsci.org/vjsArchives/v43/43-1B/43-197.pdf

4. USFWS, Migratory Bird Mortality. 2002, U.S. Fish and Wildlife Service: Arlington, VA. http://www.fws.gov/birds/mortality-fact-sheet.pdf

5.  USFWS, Perils Past and Present : Major Threats to Birds Over Time. 2003, U.S. Fish and Wildlife Service: Arlington, VA. http://www.fws.gov/birds/documents/PastandPresent.pdf

6. Gill, F.B., Ornithology. 3rd ed. 2007, New York: W.H. Freeman. xxvi, 758 p.

7. Pimentel, D., et al., “Environmental and Economic Costs of Nonindigenous Species in the United States.” Bio Science. 2000. 50(1): p. 53–65. http://www.bioone.org/doi/abs/10.1641/0006-3568%282000%29050%5B0053%3AEAECON%5D2.3.CO%3B2?journalCode=bisi

www.tcnj.edu/~bshelley/Teaching/PimentelEtal00CostExotics.pdf

8. Pimentel, D., Zuniga, R., and Morrison, D., “Update on the environmental and economic costs associated with alien-invasive species in the United States.” Ecological Economics. 2005. 52(3): p. 273–288. http://www.sciencedirect.com/science/article/B6VDY-4F4H9SX-3/2/149cde4f02744cae33d76c870a098fea

9. Hoagland, P. and Jin, D.I., “Science and Economics in the Management of an Invasive Species.”BioScience. 2006. 56(11): p. 931-935. http://www.mendeley.com/research/science-economics-management-invasive-species-8/

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. http://avmajournals.avma.org/doi/abs/10.2460/javma.2003.222.1541

11. 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

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

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. 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

15. Winter, L., “Trap-neuter-release programs: the reality and the impacts.” Journal of the American Veterinary Medical Association. 2004. 225(9): p. 1369–1376. http://avmajournals.avma.org/doi/abs/10.2460/javma.2004.225.1369

http://www.avma.org/avmacollections/feral_cats/javma_225_9_1369.pdf

16. George, W., “Domestic cats as predators and factors in winter shortages of raptor prey.” The Wilson Bulletin. 1974. 86(4): p. 384–396. http://elibrary.unm.edu/sora/Wilson/v086n04/p0384-p0396.pdf

17. Miller, J. (2010, June 24). Charge questioned in death-of-kitten case. Standard-Examiner. http://www.standard.net/topics/courts/2010/06/23/charge-questioned-death-kitten-case

18. Gurrister, T. (2010, July 22, 2010). Cruelty charge in West Haven kitten case to be dismissed Standard-Examinerhttp://www.standard.net/topics/courts/2010/07/22/cruelty-charge-west-haven-kitten-case-be-dismissed

Keys: To the Future

Below is a slightly reformatted version of the comments I submitted in response to the Florida Keys National Wildlife Refuges Complex Integrated Predator Management Plan/Draft Environmental Assessment. A PDF version is available here.

•     •     •

To Whom It May Concern:

I am writing to comment on the Florida Keys National Wildlife Refuges Complex Integrated Predator Management Plan/Draft Environmental Assessment. As I point out below, the IPMP/EA proposed by FWS fails to adequately address—or overlooks entirely—several key issues. Only now, for example—after years of struggling with this issue—does FWS propose to “imple­ment monitoring and conduct further research as needed to determine abundance and distribu­tion of free-roaming cats throughout the Refuge, document effectiveness of management actions taken or not taken on cat populations, and determine the impacts on the ecosystems and native species to aid in the adaptive management process.” [1]

How can FWS even put forward its IPMP/EA without this critical information in hand? One would expect, under the circumstances, that population estimates and scat analysis, for in­stance—along with whatever additional research might better inform any proposed action by FWS—would form the basis of such an IPMP/EA.

In addition, the IPMP/EA fails to address risks inherent with the improper management of free-roaming cats in the Keys. The plan proposed by FWS is unlikely to result in the removal of cats at a rate sufficient to keep pace with reproduction—a situation exacerbated greatly by its insistence on banning the feeding of feral cats and Trap-Neuter-Return (TNR) programs. Consequently, the population of feral cats may very well increase. And even if FWS is successful at removing cats from some locations, the IPMP/EA fails to take into account the risk of meso­predator release—the inevitable spike in non-native rodent populations—and its impact on the native species the IPMP/EA aims to protect.

For these reasons (each of which is outlined in detail below), I strongly encourage FWS to revise its IPMP/EA, especially as it pertains to the removal of feral cats.

Justification for Action
After a thorough reading of the Draft Environmental Assessment (EA) for the Florida Keys Na­tional Wildlife Refuges Complex (FKNWRC) Integrated Predator Management Plan—along with several supporting documents (as described below)—I am struck by how inadequately the IPMP/EA addresses several critical issues. Indeed, the Plan’s Justification for Management Action suggests that FWS has an insufficient and/or largely incorrect understanding of the impacts of feral and free-roaming cats on native wildlife and the environment.

Extinctions
Among the studies FWS cites to support its claim that “free-roaming cats have been shown to be a major cause of 33 native species extinction globally,” [1] is a 1987 paper by Cruz and Cruz, in which the authors, studying Galápagos Petrels, found that cats were hardly the only culprits:

“They are threatened by introduced rats, which attack eggs and young chicks… dogs and pigs which prey on eggs, nestlings and adults. Introduced goats, burros and cattle destroy nesting habitat and trample nests. A different combination of these pests and predators exists at each of the petrel nesting sites, while three of the islands are plagued by all of them.” [2]

The FWS would have the public believe the Galápagos Petrel is among those 33 extinctions. In fact, the birds are still there, though they are listed as Critically Endangered.

The story is similar for the 1986 paper by Kirkpatrick and Rauzon, another purported link between free-roaming cats and species extinctions. In fact, Kirkpatrick and Rauzon found that more than 90 percent of the diet of free-roaming cats on Jarvis Island and Howland Island was made up of Sooty Terns, Wedge-tailed Shearwaters, and Brown Noddies—each of which is listed as a species of Least Concern. [3]

Another of the papers cited by FWS has nothing to do with extinctions at all. As the authors describe it, their study was an evaluation of “whether a collar-worn pounce protector, the CatBib, reduces the number of vertebrates caught by pet cats and whether its effectiveness was influenced by colour or adding a bell.” [4]

Also listed among the “evidence” of island extinctions were studies that—in addition to having nothing to do with extinctions—were not conducted on islands. Coleman and Temple’s 1993 sur­vey, for example, involved rural Wisconsin residents and their outdoor cats, [5] while Churcher and Lawton surveyed residents of a small English village. [6]

Threatened or Endangered Species
FWS’s assertion that “many of the species impacted by free-roaming cats are federally listed threatened or endangered species and federally protected migratory birds” [1] is, while probably true, also largely meaningless. According to the 2009 State of the Birds report, published by the De­partment of the Interior:

“The United States is home to a tremendous diversity of native birds, with more than 800 species inhabiting terrestrial, coastal, and ocean habitats, including Hawaii. Among these species, 67 are federally listed as endangered or threatened. An additional 184 are species of conservation concern because of their small distribution, high threats, or declining popula­tions.” [7]

That translates to approximately 31 percent of all birds in this country being species of concern. FWS makes it sound as if perhaps the cats are targeting these birds; in fact, it’s obvious that all forms of mortality pose an acute threat to these vulnerable populations.

Disruptions to Native Ecosystems
When it comes to the disruption caused by cats to “the abundance, diversity, and integrity of na­tive ecosystems,” FWS turns to, among others, studies by Hawkins [8] and Jessup. [9]

But Hawkins’ dissertation work is plagued with problems that raise serious doubts about his rather triumphant conclusions—“the preference of ground feeding birds for the no-cat treatment was striking,” [8] for example. A closer look reveals that five of the nine ground-feeding birds in his study showed no preference for either area of the study site (a fact Hawkins downplays con­siderably). Without any explanation for why these vulnerable bird species were indifferent to the presence of an opportunistic predator, Hawkins is in no position to make the causal connections he does.

Jessup cites some well-known predation studies, but his concern is not the (presumed) impact on wildlife, per se, but rather the wholesale condemnation of “trap, neuter, and reabandon,” [9] as he calls it.

Birds and Cats
FWS claims that “free-roaming cats kill at least one billion birds every year in the U.S., repre­senting one of the largest single sources of human-influenced mortality for small native wildlife,” [1] supporting the assertion with just three sources, one of which is Rich Stallcup’s 1991 article from the Observer, a publication of the Point Reyes Bird Observatory. But “A Reversible Catastrophe” is very light on science—and, frankly, Stallcup gets most of that wrong. Mainly, the article is Stallcup’s manifesto regarding neighborhood cats:

“If you have a garden, why not proclaim it a wildlife sanctuary and protect it from non-native predators? If roaming cats come into your sanctuary to poach the wildlife under your steward­ship, you have the right and perhaps even the duty to discourage them in a serious way.” [10]

Stallcup goes on to suggest that gardeners “…try a B-B or pellet gun. There is no need to kill or shoot toward the head, but a good sting on the rump seems memorable for most felines, and they seldom return for a third experience.” [10]

Another of the studies cited by FWS—a 2008 paper by Sax and Gaines—isn’t about cats at all. Or even invasive animals. Although the authors do mention “the extinction of many native animal species on islands” [11] briefly in their introduction, the purpose of the paper is, as the authors state plainly enough, to “show that the number of naturalized plant species has increased linearly over time on many individual islands.” [11, emphasis mine]

Nevertheless, the assertion—made by FWS and many others, too—that “cats kill at least one billion birds every year in the U.S.” deserves careful scrutiny. Such aggregate figures can typically be traced to small—often flawed—studies, the results of which are subsequently extrapolated from one habitat to another, conflating island populations with those on continents, combining common and rare bird species, and so forth. Perhaps the most famous example of such pseudosci­entific manipulation is the infamous “Wisconsin Study” by Coleman and Temple.

Actually, there was no Wisconsin Study, in the scientific, peer-reviewed-publication sense. The often-cited “estimates”—which have, over the past 15 years, taken on mythical status—were nothing more than back-of-the envelopes guesses. Indeed, co-author Stanley Temple himself admitted that their figures weren’t “actual data,” though many—including the FWS—continue treating these figures as if they were actual data. “That was just our projection to show how bad it might be,” noted Temple. [12]

But Temple wasn’t as forthright about was the origin of their “estimates.” The authors’ “inter­mediate” figure of “38.7 million birds killed by rural cats” [13] is based on the results of a study involving just four “urban” cats and one rural cat in Virginia [14, 15] (this, in addition to Coleman and Temple’s several flawed assumptions). And their high estimate was even less valid.

Something else often left out of the debate: predation—even at high levels—does not automati­cally lead to population declines. In fact, some studies [16, 17] have shown that birds killed by cats are, on average, significantly less healthy than those killed through non-predatory events (e.g., collisions with buildings).

In the end, enormous “estimates” of annual predation rates are utterly meaningless—useful only as a sensational talking point by organizations interested in vilifying free-roaming cats. Such figures are routinely “sold” to a mainstream media and public unfamiliar with the larger context.

Threats to Public Health
Citing the Centers for Disease Control website, FWS argues:

“…free-roaming cats not only threaten wildlife through direct predation but also serve as vec­tors for a number of diseases including rabies, cat scratch fever, hookworms, roundworms and toxoplasmosis. Some of these diseases can be transmitted to other domestic animals, native wildlife, and in some cases, humans.” [1]

In fact, the CDC site makes no mention of cats being a threat to wildlife. And humans? “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.”

There’s even a link to another page on the CDC’s site, called “Health Benefits of Pets.”

False Premises
The numerous misrepresentations, oversights, and errors outlined above suggest quite clearly that FWS either lacks a sufficient grasp of the critical issues involved—or that it’s not interested in being forthright with the public. This is not an academic issue; nor should my detailed criticism be considered nitpicking. After all, it’s quite clear that FWS intends to eliminate free-roaming cats on public—and, if possible, also private—land throughout the Keys. As “justification for ac­tion,” the IPMP/EA falls well short of what is required; as a public record, it is wholly unaccept­able—and, to be very candid about it—an embarrassment to the agency and the people involved. Simply put, any subsequent action taken by FWS on the basis of this IPMP/EA can, I think, rightfully be considered unjustified.

Moreover, in its attempt to focus on the impacts of cats, FWS overlooks some key factors. As a result, implementation of the IPMP/EA may very well increase the threat to the Keys’ native wildlife.

Mesopredator Release
In its IPMP/EA, FWS refers to two often-cited papers [18, 19] as evidence of cats disrupting native ecosystems, but fails to acknowledge the larger point made by the authors: the mesopreda­tor release phenomenon. “In the absence of large, dominant predators,” write Soulé et al., “smaller omnivores and predators undergo population explosions, sometimes becoming four to 10 times more abundant than normal.” [18]

For Soulé et al., coyotes were the dominant predators, while cats were the mesopredators. In other contexts, however, cats have been shown to play the dominant predator role with non-native rats becoming the mesopredators. [20–23].

Mathematical modeling of the mesopredator release phenomenon illustrates the complexities involved in eradication efforts, even on small islands. As Courchamp et al. explain, “although counter-intuitive, eradication of introduced superpredators, such as feral domestic cats, is not always the best solution to protect endemic prey when introduced mesopredators, such as rats, are also present.” [22] Fan et al. warn of the risks involved with such eradication efforts: “In some cases, it may cause a disastrous impact to managed or natural ecosystems.” [21]

Macquarie Island, located roughly halfway between New Zealand and Antarctica, offers a well-documented example of such a disastrous impact. In 2000, cats were eradicated from this United Nations Educational, Scientific and Cultural Organization World Heritage Site in order to protect its seabird populations. The resulting rebound in rabbit and rodent numbers, however, has had its own disastrous impact. “In response, Federal and State governments in Australia have committed AU$24 million for an integrated rabbit, rat and mouse eradication programme.” [23]

Mesopredator Release in the Keys
But FWS doesn’t even mention the risk of mesopredator release in its IPMP/EA, despite the fact that—should the population of free-roaming cats be sufficiently reduced—the situation in the Keys suggests that such an outcome is actually quite likely. (Because the population and diet of these cats is poorly understood in the Keys, the degree of reduction that would trigger a mesopredator release, too, is unknown.)

According to FWS, non-native rats are already “prevalent in residential and commercial areas.” [1] Should the removal of cats create a spike in their numbers, FWS suggests that they’re prepared to remove the rats, too: “Noticeable population increases based on reports, road kill, or other specific or auxiliary data may initiate targeted control and eradication efforts in addition to incidental capture…” [1]

But controlling these rats is complicated considerably by the need to protect Lower Keys marsh rabbits. The South Florida Multi-Species Recovery Plan (MSRP) warns of these rabbits coming into contact with pesticides and “poisons used to control black rats.” [24]

“In a 1993 Biological Opinion, the FWS investigated the effects of vertebrate control agents on endangered and threatened species and determined that several chemicals (e.g., Pival) would jeopardize the continued existence of the Lower Keys marsh rabbit. Chemicals—such as Pival—a rodenticide used to kill rats, are lethal if ingested. The FWS also concluded that if development in the Keys continues to increase, the potential for these animals to come in contact with such chemicals also increases, as does the potential for their extinction. Based on these findings, the FWS believes the continued use of such chemicals will result in the deaths of Lower Keys marsh rabbits. Given that the majority of occupied habitat is adjacent to urbanized areas, and that urbanization continues to expand into their habitat, then it can reasonably be predicted that the use of such chemicals has had a negative impact upon the Lower Keys marsh rabbit that may prevent its recovery.” [24]

Again, there’s no consideration whatsoever in the IPMP/EA for how the Lower Keys marsh rabbits—the protection of which was a key factor in the creation of the IPMP/EA in the first place—will be protected from increased predatory pressure by non-native rats. Yet, based on the evidence presented by FWS, it’s quite clear that the elimination of free-roaming cats in the Keys will very likely have a negative impact on their numbers—and may very well lead to the extirpation of marsh rabbits from any Key where these rats are present.

The same may be true of the Key Largo cotton mouse [25, 26], Key Largo woodrat [27, 28], and silver rice rat [29, 30], all of which are identified as species of particular concern in the IPMP/EA, and which are threatened—either through predation or competition—by non-native rats such as the black rat.

Alternatives
According to FWS, “the Proposed Action is a fully integrated range of nonlethal and lethal predator management strategies that would be available for implementation on the FKNWRC, depending on the status, distribution, and extent of predation by targeted predator species.” [1] Where feral cats are concerned, however, the “Proposed Action” is nothing more than the “tradi­tional” trap-and-kill approach—this, despite the fact that FWS lacks sufficient data concerning the distribution of, and extent of predation by, feral cats.

FWS is less than forthright on this point, however. According to the IPMP/EA:

“The Monroe County animal control service provider will have the authority to determine the final disposition of the trapped cats according to county ordinances and standards, which may include returning to owner, adopting out, relocating to a long-term cat care facility on the mainland, or euthanizing.” [1]

It’s no secret what happens to nearly every feral cat brought into shelters. As Nathan Winograd writes in his book Redemption: The Myth of Pet Overpopulation and the No Kill Revolution in America, “there is no other animal entering a shelter whose prospects are so grim and outcome so certain.” [31]

I asked Connie Christian, Executive Director of the Florida Keys SPCA about this last month. “Every cat brought to our facility is assessed to determine their disposition,” Christian told me via e-mail. “Every attempt is made to return ‘non-feral’ cats to their owners or place for adoption.”

“Unfortunately,” she continued, “we do not have an outlet for feral cats that are brought to us without a request for return.” Which would likely be the case for cats unlucky enough to be trapped by FWS.

(As I understand it, there was a no-kill shelter available at the time of the stakeholder meetings, thus buy-in from those concerned for the welfare of these cats. However, as this is no longer the case (again, this is my understanding of the situation), FWS cannot assume that the same level of buy-in exists today. And in any case, the suggestion of a no-kill shelter or sanctuary as a solution to the Keys’ feral cat issue is at best disingenuous.)

Removing Cats
Setting aside for the moment the issues mentioned above, the IPMP/EA offers little to suggest that FWS will actually be able to remove the free-roaming cats from the Keys. The fact that the agency has no idea how many cats there are is only the beginning. Reports indicate that FWS has a rather poor track record when it comes to trapping cats. Its 2003 contract with USDA, for example, yielded just 23 cats over 31 days of trapping. [32]

In 2007, FWS “received $50,000 to remove cats from federal refuges on Big Pine Key and Key Largo, and to protect endangered marsh rabbits, silver rice rats and other animals and birds that call the refuges home.” [33] Unofficial reports (I’m told nothing official has been issued yet) suggest that fewer than 20 cats were caught—some of which were clearly not feral—along with 81 raccoons, 53 of which were released alive. [34]

I think it’s safe to say that the Keys’ wildlife reaped little or no benefit from either effort. Had the 2007 funding been used for TNR, on the other hand, the impact could have been substantial.

Eradication Efforts
As I’m sure FWS is aware, numerous eradication efforts—the horrors of which are spelled out in some of the papers cited in the IPMP/EA—have been used to successfully remove cats from islands:

  • Nogales et al., describing the “success” of Marion Island, note, “it took about 15 years of intense effort to eradicate the cats, combining several methods such as trapping, hunting, poi­soning, and disease introduction… The use of disease agents or targeted poisoning campaigns hold promise for an initial population reduction in eradication programs on large islands—such an approach may save effort, time, and money.” [35]
  • Cruz and Cruz point out that, of all the non-native mammals there, cats were “the most dif­ficult to control or eliminate on Floreana Island.” Although “hunting with dogs was the single most effective method employed and it gave a sure body count,” the authors warn that “the method was costly and with the limited manpower available was only useful over small areas. Both poisoning and trapping were effective and the combination of the three methods is probably the most effective approach, as well as being the best use of time and materials.” [2]
  • Veitch describes efforts on 11-square-mile Little Barrier Island as “a determined [cat] eradi­cation attempt” involving “cage traps, leg-hold traps, dogs and 1080 poison were used, but leg-hold traps and 1080 poison were the only effective methods.” [35] Four cats were also infected with Feline enteritis, but “because of the poor reaction to the virus no other cats were dosed and none were released… Altogether, 151 cats were known to have been killed before the eradication was declared complete. Important lessons learnt can be transferred to other feral cat eradication programmes.” [36] (By way of comparison, the Keys are approximately 137 square miles in total area.)

As FWS notes in its IPMP/EA, such methods are “not… socially acceptable” and “inconsistent with the points of consensus developed by the stakeholder group.” While I agree completely that these methods are unacceptable, the “fully integrated range of nonlethal and lethal predator man­agement strategies” proposed by FWS strike me as nothing more than business as usual. How will this be any different (other than perhaps in terms of scale) than the failed efforts of the past?

If implemented as-planned, it seems clear that FWS will not be able to remove the cats quickly enough to keep up with reproduction rates. Using a population model, Andersen, Martin, and Roemer have suggested that, in the absence of a sterilization program, 50 percent of cats would have to be removed in order for a colony to decrease 10 percent annually. [37] This model has its flaws (some of which are described in “Reassessment”) but even if Andersen et al. are off by a factor of two, FWS would need to remove 25 per­cent of the free-roaming, unsterilized (and in the absence of TNR, it won’t be long before that’s the norm) cats continuously in order to achieve a modest 10 percent annual reduction in overall numbers.

Does anybody at FWS really think that’s going to happen? Where’s the evidence to suggest that it’s even possible?

If the feeding of feral cats and TNR are eliminated (to whatever extent possible) throughout the Keys, these cats will simply “go underground.” That means no more monitoring—and steriliz­ing—by the “foot soldiers” who currently care for them.

Indeed, it’s quite likely that feral cat complaint calls to Monroe County, FWS, and USDA would taper off considerably, as it becomes clear that such a call is essentially a death sentence. Thus, the cats would become that much more difficult to locate—and sterilize. The population, there­fore, would increase—probably very quickly.

In other words, the most likely outcome of the IPMP/EA put forward by FWS is an increase in the number of feral cats in the Keys—and, of course, a corresponding increase in the negative impacts they have on the area’s wildlife and environment.

Trap-Neuter-Return
In contrast to the IPMP/EA—with its risk of mesopredator release, on the one hand, and poten­tial to inadvertently drive up the numbers of feral cats, on the other—TNR offers the potential to more carefully manage the population of feral cats in the Keys. Indeed, given the precarious nature of wildlife in the Keys, TNR may actually be the best approach to fulfill the purpose of the IPMP/EA:

“…conserve and restore federally-listed species and protect all native fauna and flora on the [refuges] from population decline and potential extirpation or extinction due to predation by non-native species and human-subsidized populations of native predators.” [1]

The fact that TNR was “considered but dismissed from further evaluation,” again, suggests that FWS failed to adequately analyze all of the available predator management alternatives. And, similar to its “justification for action,” FWS’s rationale for dismissing TNR doesn’t hold up to scrutiny.

FWS argues, for example, that TNR “does little to reduce cat predation on native wildlife.” Al­though few predation studies have examined the hunting behavior of cats belonging to managed colonies, those that have are revealing. Reporting on their study of free-roaming cats in Brook­lyn, Calhoon and Haspel write: “Although birds and small rodents are plentiful in the study area, only once in more than 180 [hours] of observations did we observe predation.” [38]

And Castillo and Clarke (though highly critical of TNR) actually documented remarkably little predation in the two Florida parks they used for their study. 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” [39] 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.” [39]

“In addition,” argues FWS, “the TNR method has little valid scientific support for claims that it actually reduces cat colony numbers over time and often has been shown to attract people to release new cats into an area.” [1] Ironically, some of the greatest TNR success stories are right there in the papers cited by FWS. Natoli, for example, 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.” [40] And, as of 2004, ORCAT, run by the Ocean Reef Community Associa­tion, had reduced its “overall population from approximately 2,000 cats to 500 cats.” [41] Accord­ing to the ORCAT website, the population today is approximately 350, of which only about 250 are free-roaming.

Any TNR program contends with the unfortunate (and illegal) dumping of cats. Still, it’s difficult to imagine that the presence or absence of a nearby TNR program would affect a person’s decision to abandon his/her pet cat(s). (If any studies had demonstrated such a connection, TNR opponents would surely cite them.) On the other hand, cats dumped near a managed colony are far more likely to be adopted and/or sterilized—thereby mitigating their potential impact on the overall population of unowned cats—as well any impacts to wildlife and the environment.

Moreover, FWS ignores the value of population stabilization. Julie Levy, Maddie’s Professor of Shelter Medicine in the University of Florida’s College of Veterinary Medicine, and one of the country’s foremost experts on feral cats, argues that “wildlife benefits when populations of cats that are trending rapidly upwards are at least stabilized.” [42] Nothing in the IPMP/EA suggests that such stabilization will be achieved in the Keys.

ESA and MBTA
Among the more perplexing aspects of FWS’s argument is their claim that “TNR practices are prohibited on National Wildlife Refuges, and violate the Endangered Species Act (ESA) and the Migratory Bird Treaty Act (MBTA) because they may result in the direct harm of protected species.”

This is an argument that’s been thrown around since at least 2003, when Pamela Jo Hatley, then a law student, suggested the possibility. But that’s all it was—and, apparently, is—a possibility.

“It is quite obvious that cats can be lethal to birds,” writes Hatley, “and if the death of a migratory bird can be traced to a cat, or a cat colony, which can be further traced to an individual or orga­nization, there may be strict liability for that person under the MBTA.” [43] Hatley’s argument for violations of the Endangered Species Act is similarly speculative: “…persons who release cats into the wild or who maintain feral cat colonies could be found liable for a take under section 9 of the ESA if maintenance of feral cats in the wild is found to kill or injure wildlife by degrading habitat.” [43]

It’s been nearly eight years now—a period during which TNR has undoubtedly increased substantially across the country—so where are all the court cases? If this were as black-and-white as FWS makes it sound, there wouldn’t even be a discussion about TNR (and the Urban Wildlands Group would likely have taken a very different tack in its opposition to TNR in Los Angeles).

Summary
There is no doubt that the Florida Keys are immensely valuable for their diversity of animal and plant life, some of which can be found nowhere else in the world. Due to a wide range of fac­tors—most of them human-caused—this habitat has become quite fragile, with some animal and plant species on the brink of extinction. Ecosystems—especially those as fragile as the Keys—are incomprehensibly complex, and tinkering with them is incredibly risky. And there’s plenty we simply do not know, and cannot—despite our best efforts—predict.

In its attempt to eliminate free-roaming cats from the Keys, FWS overlooks several important factors, thereby imposing a greater risk to the very native wildlife it aims to protect.

The IPMP/EA proposed by FWS fails to adequately address (1) the presumed impacts of free-roaming cats on native wildlife in the Keys, and (2) the risks inherent with the improper man­agement of these cats. It’s easy to imagine the losers in the deal—the cats, obviously, but also all of the wildlife FWS wants to protect. And the taxpayers, too, of course—this promises to be a dismal return on investment for all of us, no matter what our position might be on feral cats, wildlife conservation, and the like. The question is, where are the winners?

I strongly encourage FWS to revise its IPMP/EA, paying particular attention to these two issues, and to give further consideration to TNR in light of these and other important factors outlined in this letter.

Respectfully,

Peter J. Wolf
Independent Researcher/Analyst
www.VoxFelina.com

Literature Cited

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http://www.fws.gov/nationalkeydeer/pdfs/USFWS%20FL%20Keys%20Refuges%20Integrated%20Predator%20Mgmt%20Plan%20&%20EA%20FINAL%20DRAFT.pdf

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20. Fitzgerald, B.M., Karl, B.J., and Veitch, C.R., “The diet of feral cat (Felis catus) on Raoul Island, Kermadec group.” New Zealand Journal of Ecology. 1991. 15(2): p. 123–129. http://www.feral.org.au/the-diet-of-feral-cats-felis-catus-on-raoul-island-kermadec-group/

www.newzealandecology.org.nz/nzje/free_issues/NZJEcol15_2_123.pdf

21. Fan, M., Kuang, Y., and Feng, Z., “Cats protecting birds revisited.” Bulletin of Mathematical Biology. 2005. 67(5): p. 1081–1106. http://www.springerlink.com/content/p0h5854n56183874/

22. Courchamp, F., Langlais, M., and Sugihara, G., “Cats protecting birds: modelling the mesopredator release effect.” Journal of Animal Ecology. 1999. 68(2): p. 282–292. http://dx.doi.org/10.1046/j.1365-2656.1999.00285.x

http://deepeco.ucsd.edu/~george/publications/99_cats_protecting.pdf

23. 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

24. n.a., Multi-Species Recovery Plan for South Florida: Lower Keys Rabbit. 1999, U.S. Fish and Wildlife Service: Atlanta, GA. p. 151–171. http://www.fws.gov/verobeach/index.cfm?Method=programs&NavProgramCategoryID=3&programID=107&ProgramCategoryID=3

www.fws.gov/verobeach/images/pdflibrary/lkmr.pdf

25. n.a., Multi-Species Recovery Plan for South Florida: Key Largo Cotton Mouse. 1999, U.S. Fish and Wildlife Service: Atlanta, GA. p. 79–96. http://www.fws.gov/verobeach/index.cfm?Method=programs&NavProgramCategoryID=3&programID=107&ProgramCategoryID=3

http://www.fws.gov/verobeach/images/pdflibrary/klcm.pdf

26. n.a., Key Largo Cotton Mouse (Peromyscus gossypinus allapaticola) 5-Year Review: Summary and Evaluation. 2009, U.S. Fish and Wildlife Service, Southeast Region, South Fiorida Ecological Services Office: Veero Beach, FL. p. 19. http://ecos.fws.gov/speciesProfile/profile/speciesProfile.action?spcode=A086

http://ecos.fws.gov/docs/five_year_review/doc2378.pdf

27. n.a., Multi-Species Recovery Plan for South Florida: Key Largo Woodrat. 1999, U.S. Fish and Wildlife Service: Atlanta, GA. p. 195–216. http://www.fws.gov/verobeach/index.cfm?Method=programs&NavProgramCategoryID=3&programID=107&ProgramCategoryID=3

http://www.fws.gov/verobeach/images/pdflibrary/klwr.pdf

28. n.a., Key Largo Woodrat (Neotomafloridana smalli) 5-Year Review: Summary and Evaluation. 2008, U.S. Fish and Wildlife Service, Southeast Region, South Fiorida Ecological Services Office: Vero Beach, FL. http://ecos.fws.gov/speciesProfile/profile/speciesProfile.action?spcode=A087

http://www.ecos.fws.gov/docs/five_year_review/doc1985.pdf

29. n.a., Multi-Species Recovery Plan for South Florida: Rice Rat. 1999, U.S. Fish and Wildlife Service: Atlanta, GA. p. 173–194. http://www.fws.gov/verobeach/index.cfm?Method=programs&NavProgramCategoryID=3&programID=107&ProgramCategoryID=3

http://www.fws.gov/verobeach/images/pdflibrary/srra.pdf

30. n.a., Rice rat (Oryzomys palustris natator) 5-Year Review: Summary and Evaluation. 2008, U.S. Fish and Wildlife Service, Southeast Region, South Florida Ecological Services Office: Vero Beach, FL. http://ecos.fws.gov/speciesProfile/profile/speciesProfile.action?spcode=A083

http://ecos.fws.gov/docs/five_year_review/doc1958.pdf

31. Winograd, N.J., Redemption: The myth of pet overpopulation and the no kill revolution in America. 2007: Almaden Books. http://www.nathanwinograd.com/?page_id=164

32. n.a., Feral and Free-Ranging Cat Trapping by the USDA, APHIS, Wildlife Services (WS) on North Key Largo. 2004, U.S. Department of Agriculture

33. 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

34. 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

35. 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

36. Veitch, C.R., “The eradication of feral cats (Felis catus) from Little Barrier Island, New Zealand.”New Zealand Journal of Zoology. 2001. 28: p. 1–12. http://www.royalsociety.org.nz/publications/journals/nzjz/2001/001/

http://www.royalsociety.org.nz/media/publications-journals-nzjz-2001-001.pdf

37. 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. http://www.avma.org/avmacollections/feral_cats/default.asp

http://www.avma.org/avmacollections/feral_cats/javma_225_12_1871.pdf

38. Calhoon, R.E. and Haspel, C., “Urban Cat Populations Compared by Season, Subhabitat and Supplemental Feeding.” Journal of Animal Ecology. 1989. 58(1): p. 321–328. http://www.jstor.org/pss/5003

39. 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.

40. 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

41. 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

42. Levy, J.K., Personal communication, 2010.

43. Hatley, P.J., Feral Cat Colonies in Florida: The Fur and the Feathers Are Flying. 2003, University of Florida Conservation Clinic: Gainsville, FL. http://www.animallaw.info/articles/arus18jlanduseenvtll441.htm

www.law.ufl.edu/conservation/pdf/feralcat.pdf

On Invasion and Persuasion

Smithsonian magazine is, according to its website, “created for modern, well-rounded individuals with diverse interests” and “chronicles the arts, history, sciences and popular culture of the times.” Jess Righthand’s recent article, “The World’s Worst Invasive Mammals,” seems—despite its inclusion in the online edition’s “Science & Nature” section—better suited for the pop culture category.

Indeed, the story has more to do with sensationalism than science.

Feral Cat Population
Righthand’s claim that “there are an estimated 60 million feral cats in the United States alone” is conservative compared to some other estimates. David Jessup, for example, suggested in 2004 that there were 60–100 million [1], while, more recently, The American Bird Conservancy Guide to Bird Conservation puts the figure at 60–120 million [2] (neither cites a source).

Still, Merritt Clifton of Animal People, an independent newspaper dedicated to animal protection issues, makes a compelling argument that the population of feral cats in the U.S. is much smaller than is often reported, and may very well be on the decline. [3]

Clifton’s estimates are derived not from surveys of homeowners feeding stray and feral cats, but from “information about the typical numbers of cats found in common habitat types, gleaned from a national survey of cat rescuers… cross-compared with animal shelter intake data.” [4] In 2003, Clifton suggested that “the winter feral cat population may now be as low as 13 million and the summer peak is probably no more than 24 million.” [4]

Predation on Birds
Righthand puts the figure for annual bird deaths attributed to feral cats at “around 480 million.” Nowhere near the “one billion birds” proposed by Nico Dauphine and Robert Cooper, [5] of course, but more than enough to get the attention of Smithsonian readers.

But, as I’ve pointed out repeatedly, even high rates of predation do not equate to population declines (though, clearly, it’s easy to suggest as much). Many researchers have disputed the kind of broad, overreaching claims to which Righthand alludes. Biologist C.J. Mead, for example, reviewing the deaths of “ringed” (banded) birds reported by the British public, suggests that cats may be responsible for 6.2–31.3 percent of bird deaths. “Overall,” writes Mead, “it is clear that cat predation is a significant cause of death for most of the species examined.” Nevertheless, Mead concludes:

“there is no clear evidence of cats threatening to harm the overall population level of any particular species… Indeed, cats have been kept as pets for many years and hundreds of generations of birds breeding in suburban and rural areas have had to contend with their predatory intentions.” [6]

Mike Fitzgerald and Dennis Turner come to essentially the same conclusion: “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.” [7]

Then, too, there’s the critical distinction between compensatory and additive predation—again, a point I’ve made numerous times. Two very interesting studies have generated compelling evidence that birds killed by cats are, on average, significantly less healthy than those killed through non-predatory events (e.g., collisions with buildings). [8, 9] In other words, these birds probably weren’t going to live long enough to contribute to the overall population numbers; predation was compensatory rather than additive.

Public Health Threats
“When house cats are allowed free range outdoors by their owners,” argues Righthand, “or simply don’t have owners, they not only wreak havoc as opportunistic hunters, they can also spread disease. In addition to carrying rabies, 62 to 82 percent of cats in a recent study tested positive for toxoplasmosis.” Here, Righthand seems to be cribbing off of Hildreth, Vantassel, and Hygnstrom, of “Feral Cats and Their Management” fame—hardly a reputable source.

Rabies
Regarding rabies—a topic I’ll save for future posts—I think it’s important to put this into perspective. I happen to have data from Florida handy, and according to that state’s Department of Health, approximately 22,000 Florida residents have died of the flu or pneumonia since 2006 (actually, that figure accounts for only 24 of Florida’s 67 counties, so the total is surely much higher).

By way of comparison: from 2005 through mid-May of this year, there were 11 reported cases of rabies in humans across the entire country (though, I believe there were a handful of reported cases this summer as well).

In terms of public health, then, I think we’re all better off focusing on frequent hand washing, sneezing into our sleeves, and the like—as opposed to, say, exterminating this country’s most popular companion animal by the millions.

Toxoplasma gondii (I)
While it’s true that cats are the definitive host of Toxoplasma gondii, it’s important to note that “wild game can be a source of T. gondii infection in humans, cats, and other carnivores. Serologic data show that a significant number of feral pigs, bears, and cervids are exposed to T. gondii. [10]

“Humans,” write Elmore et al., “usually become infected through ingestion of oocyst-contaminated soil and water, tissue cysts in undercooked meat, or congenitally. Because of their fastidious nature, the passing of non-infective oocysts, and the short duration of oocyst shedding, direct contact with cats is not thought to be a primary risk for human infection.” [11]

But to Righthand’s point: the rate of cats testing positive—or seroprevalence—is, in any event, not a useful measure of their ability to infect other animals or people.

According to Dubey and Jones, “most cats seroconvert after they have shed oocysts. Thus, it is a reasonable assumption that most seropositive cats have already shed oocysts.” [12] “Testing positive,” in this case, is nothing more than the detection of antibodies resulting from seroconversion (the same process, by the way, that takes place in humans after receiving a flu shot).

So, what exactly is Righthand’s point? Did she simply not do her homework here, or is the idea to portray these cats as a threat far, far beyond what the scientific evidence supports? Both, I suspect.

Toxoplasma gondii (II)
T. gondii
, Righthand continues, “has been shown to cause neurological damage to sea otters and other marine mammals that are exposed when heavy rainfall washes infected cat feces into the water.” Again, this is terrain I’ve covered previously. (Righthand, it seems, could do herself—and Smithsonian readers—a favor by subscribing to Vox Felina!)

Yes, T. gondii has been linked to the illness and death of marine life, primarily sea otters [13], prompting investigation into the possible role of free-roaming (both owned and feral) cats. [14, 15] It’s generally thought that oocysts (the mature, infective form of the parasite) are transferred from soil contaminated with infected feces to coastal waterways by way of freshwater run-off. [15]

However, one study found that 36 of 50 sea otters from coastal California were infected with the Type X strain of T. gondii [16], a type linked to wild felids (mountain lions and a bobcat, in this case), but not to domestic cats. [15] A recently published study from Germany seems to corroborate these findings. Herrmann et al. analyzed 18,259 fecal samples (all from pet cats) for T. gondii and found no Type X strain. (It’s interesting to note, too, that only 0.25% of the samples tested positive for T. gondii). [17]

Once again, we’re back to the question: What is Righthand trying to accomplish here?

Population Impacts
“Cats have,” writes Righthand, “also hurt populations of birds, reptiles and other creatures. The black stilt of New Zealand (a seabird), the Okinawa woodpecker and the Cayman Island ground iguana are just a few of the dozens of endangered species at risk due to the proliferation of feral cats.”

At the risk of pointing out the obvious, endangered species are—by definition—at risk due to the proliferation of all sorts of threats. That’s how they became endangered in the first place. To suggest, as Righthand does, that cats are the sole threat these animals face is both misleading and irresponsible.

Righthand (taking a cue, perhaps, from the authors of The ABC Guide?) also makes the common mistake of using island impacts (which are, themselves, more complex than often acknowledged) to imply impacts elsewhere (better yet: everywhere). Readers, it seems, are on their own in terms of doing any research on the topic.

Mission Failure
How much of the blame we can put on Righthand, I don’t know. According to Smithsonian’s website, she’s an intern with the magazine. Had the editors wanted a more thoroughly researched article, they could have demanded one. (This, some readers will recall, is not the first time I’ve been disappointed with the Smithsonian’s lack of rigor.)

According to its website, the mission of the Smithsonian is straightforward but ambitious: “the increase and diffusion of knowledge.” Righthand’s article—misleading at best—falls well short. It seems she’s still struggling with how to best express the organization’s proclaimed values—in this case, going overboard on the creativity at the expense of excellence and integrity.

Literature Cited
1. Jessup, D.A., “The welfare of feral cats and wildlife.” Journal of the American Veterinary Medical Association. 2004. 225(9): p. 1377-1383. http://avmajournals.avma.org/doi/abs/10.2460/javma.2004.225.1377

2. 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. Clifton, M. (2003) Roadkills of cats fall 90% in 10 years—are feral cats on their way out? http://www.animalpeoplenews.org/03/11/roadkills1103.html Accessed May 23, 2010.

4. Clifton, M. Where cats belong—and where they don’t. Animal People 2003 [cited 2009 December 24].  http://www.animalpeoplenews.org/03/6/wherecatsBelong6.03.html.

5. 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. www.pwrc.usgs.gov/pif/pubs/McAllenProc/articles/PIF09_Anthropogenic%20Impacts/Dauphine_1_PIF09.pdf

6. Mead, C.J., “Ringed birds killed by cats.” Mammal Review. 1982. 12(4): p. 183-186. http://dx.doi.org/10.1111/j.1365-2907.1982.tb00014.x

7. 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.

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. http://dx.doi.org/10.1111/j.1474-919X.2008.00836.x

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. Hill, D.E., Chirukandoth, S., and Dubey, J.P., “Biology and epidemiology of Toxoplasma gondii in man and animals.” Animal Health Research Reviews. 2005. 6(01): p. 41-61. http://journals.cambridge.org/action/displayAbstract?fromPage=online&aid=775956&fulltextType=RA&fileId=S1466252305000034

11. Elmore, S.A., et al., “Toxoplasma gondii: epidemiology, feline clinical aspects, and prevention.” Trends in Parasitology. 26(4): p. 190-196. http://www.sciencedirect.com/science/article/B6W7G-4YHFWNM-1/2/2a468a936eb06649fde0463deae4e92f

12. 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

13. 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

14. 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://avmajournals.avma.org/doi/abs/10.2460/javma.229.1.74

15. 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

16. 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

17. 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

Rap(tor) Sheet

Perhaps it’s an act of desperation, this “kitchen sink” approach favored by some free-roaming cat/TNR opponents. Throw everything—including the kitchen sink—into the anti-cat argument, and perhaps something will stick. Their impact on wildlife and the environment, for instance, or their threat to public safety—it seems there’s something for everybody. (Surely it’s only a matter of time before beach erosion, ozone depletion, and climate change are added to this growing rap sheet.)

But for those of us willing to sort through this quantity-over-quality smokescreen, such arguments rarely prove substantive.

I touched on this point in one of my first Vox Felina posts, referring to how the now-classic predation study conducted by William G. George has been misread, misinterpreted, and misrepresented. This work, perhaps more than any other, has been used to suggest an indirect impact of free-roaming cats on raptors.

George was very cautious about drawing such a connection, acutely aware of the speculative nature of his own work. In recent years, however, the details of George’s work—and his well-tempered conclusions—have given way to a kind of mythology, having been co-opted by scientists more interested in their own agendas than in rigorous scientific inquiry.

The Study
Over four years, from January 1, 1968 through December 31, 1971, George monitored and recorded with meticulous care the various small mammals his three cats killed on his “fallow farmland” property in rural Cobden, Illinois. “As predators on rodents,” writes George, “cats inevitably compete for prey with many of our declining raptors, and therein may lie a serious problem.” (emphasis mine) [1].

“I am not suggesting a cause-and-effect relationship exists between the historical increase of cats and the historical decrease of raptors; however, cats, which are as efficient in their way as guns and DDT, accompany and add another dimension to man’s encroachment into wildlife areas.” [1]

The trouble, of course, is that so many scientists citing George’s work have suggested exactly that.

The Myth
“Cat predation on mammals,” write Longcore et al., is “cause for concern because of direct impacts to native species and competition with native predators (George 1974).” [2] “Human-subsidized cats,” warn Guttilla and Stapp, “can spill over into less densely populated wildland areas where they reduce prey for native predators (George 1974).” [3]

Of course anybody who grew up, as I did, watching Wild Kingdom, knows that competition is a central theme of many stories played out in the natural world. But competition for prey is one thing; having an impact on the population of competitors is something else altogether.

Which is precisely what Loyd and DeVore—citing only George’s research—suggest: “Feral cats can also have a considerable impact on the broader health of ecosystems by outcompeting native predators (George 1974)…” [4]

Dauphiné and Cooper, too, interpret George’s work rather loosely, but also seem to offer additional evidence of the indirect impacts about which he speculated:

“In addition to having direct impacts on prey, cats compete with avian predators, such as American Kestrels (Falco sparverius), Northern Harriers (Circus cyaneus), and Redtailed Hawks (Buteo jamaicensis) (George 1974, Mosher 1989, Lepczyk et al. 2004). George (1974) estimated that cats killed 5.5 million rodents and other vertebrates in a 26,000 square mile area in Illinois, effectively depleting the prey base for wintering raptors and other native predators.” [5]

What did Lepczyk add to the conversation? Nothing, actually; he merely cited George’s study:

“… cats may be directly competing with avian predators, such as American Kestrels (Falco sparverius), Northern Harriers (Circus cyaneus) and Red-tailed Hawks (Buteo jamaicensis; George, 1974).” [6]

And Mosher? This one’s far more interesting. According to Dauphiné and Cooper, Mosher’s research reveals some compelling evidence:

“In a study in Maryland of Cooper’s Hawks (Accipiter cooperii) that depended heavily on eastern chipmunks (Tamias striatus) to feed nestlings, Mosher (1989) found that these raptors altered their diet to prey more on songbirds in an area where chipmunks were eradicated by cats. The resulting increase in hunting time and difficulty for Cooper’s Hawks was associated with a decrease in nestling survival.” [5]

But Mosher’s paper includes no mention of cats at all. In fact, he suggests only “that reproductive performance, especially in studies encompassing relatively small areas, may reflect natural phenomena such as dependence on a particular prey species that undergoes population fluctuations.” [7] I found an earlier paper by Mosher, also mentioning chipmunks and Cooper’s Hawks [8]—but again, no mention of cats.

It’s possible this is an honest mistake, that Dauphiné and Cooper merely included the wrong reference. However, I was unable to find a hint of any such research in my (admittedly brief) online sleuthing. And, given the sloppiness and bias that permeates the rest of their paper, nothing these two might do would surprise me.

(If, as Dauphiné and Cooper suggest, the real problem is that raptors are preying on songbirds rather than chipmunks, then shouldn’t we be doing everything in our power to increase the chipmunk population? It’s an absurd suggestion, of course—but only slightly more so than many accepted wildlife “management” practices.)

Getting back to George’s research, the winner for most distorted version undoubtedly goes to David Jessup, who writes with a certitude generally reserved for politicians, marketers, and novelists. Gone is the trepidation 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.” [9]

Local/Regional Raptor Update
So, how have those raptors fared in the subsequent 40 years? Certainly there are factors other than cats that would likely contribute to their decline—habitat fragmentation and destruction, for instance. Such environmental impacts have the potential to affect the birds themselves, clearly, but also their prey.

Research into the population trends of Red-tailed Hawks, Northern Harriers, and American Kestrels—three raptors identified specifically by George—suggests that his concerns were largely unfounded.

BBS Routes and Data
Only one Breeding Bird Survey (BBS) route runs into Union County, Illinois, where George’s property was located. Unfortunately, count data for BBS Route 34080 go back only to 1993. However, data for neighboring routes are available from the time of George’s study through 2006. Surveys along two nearby routes in Illinois (34059 and 34061) began in 1970; surveys of two others, along the eastern edge of Missouri (52001 and 52007), date back to 1967.

Selected BBS Routes: Missouri and Illinois

No BBS count data from the routes in question are available for Northern Harriers, suggesting that perhaps this species was, for one reason or another, simply not included. Data sets for other birds—the Red-shouldered Hawk, for example—exist despite frequent counts of zero (in the case of the Red-shouldered Hawk, just one bird was recorded along Routes 52001 from 1967 through 2006).

BBS data for Red-tailed Hawks indicate a rather dramatic population increase for the two southwestern Illinois routes, and slight increases for the same period across the two eastern Missouri routes, as indicated in the following graphs.

Red-tailed Hawks Four BBS RoutesBBS Data: Red-tailed Hawks for two Illinois and two Missouri routes (adapted from North American Breeding Bird Survey website)

Populations of American Kestrels (along the same routes and for the same period) remained mostly stable.

American Kestrels Four BBS RoutesBBS Data: American Kestrels for two Illinois and two Missouri routes (adapted from North American Breeding Bird Survey website)

The bottom line? If the area’s cats are out-competing the raptors for prey, there’s no evidence in the BBS count data.

Prairie Voles
Of particular interest to George were prairie voles, which made up “more than 41 percent of all captured vertebrates and 45 percent of the captured mammals.” [1] And whose reduced numbers, suggested George, “could well pose the principal threat to the success of wintering hawks in my area of study.” [1] But maybe the voles weren’t as important as George surmised.

In Minnesota, the declining population of prairie voles—significant enough to warrant “special concern species” status beginning in 1984—seems to have had no effect on the populations of Northern Harriers, Red-tailed Hawks, and American Kestrels. Indeed, BBS data indicate that these raptors’ numbers have fluctuated little over the past 40 years or so. (And, according to the Minnesota Department of Natural Resources, the reason for the state’s declining vole numbers has nothing to do with cats, but “is due almost exclusively to the destruction of its prairie habitat through plowing and over-grazing.”)

BBS Data: Three Raptors across MinnesotaBBS Data: Three raptor species across Minnesota (adapted from North American Breeding Bird Survey website)

Raptors Across the Country
Of course, isolating the relationship between the population of a predator and that of its preferred prey species is incredibly difficult; there are simply too many additional—often interdependent—factors that must be considered. Zooming out for a big-picture view of population dynamics across the U.S. only blurs such relationships, thereby complicating any subsequent analysis.

Nevertheless, I think it’s worth a look. George claimed (unfortunately, without referring to a specific source, and without specifying whether he was referring only to owned/pet cats) that there were 31 million cats in the U.S. at the time of his study. [1] Today, according to the American Pet Products Association’s 2009–2010 National Pet Owners Survey, there are 93.6 million.

Direct comparisons over this 40-year time frame are difficult for a number of reasons (e.g., lack of reliable data, the increasing proportion of indoor-only cats in recent years, etc.). But if, as some suggest, cats are having an negative impact on raptor populations—and there are now three times as many of them (not accounting for feral cats, whose numbers have also likely increased)—well, one might expect find these birds in dire straights by now.

Hawk Mountain Sanctuary
To see for myself, I turned to Hawk Mountain Sanctuary’s Conservation Status Reports. Located in east-central Pennsylvania, Hawk Mountain Sanctuary is, according to its website, “the world’s first refuge for birds of prey.”

The outlook for the Northern Harrier and Red-tailed Hawk is mostly good. “The Northern Harrier is considered secure in most of North America,” notes its 2007 conservation report, “but it is a species of concern regionally in many of the [Bird Conservation Regions] west of the Mississippi River.”

The Red-tailed Hawk, too, “is considered secure throughout most of its range in North America.

“Migration counts have declined in eastern North America since 1995, but concurrent increases in [Breeding Bird Surveys] and [Christmas Bird Counts] suggest that these migration trends may be the result of changes in migration geography or behavior. Elsewhere in North America, population monitoring generally indicates increasing or stable populations of this common raptor.”

American Kestrels, on the other hand, seem to be in trouble: “Overall, the data suggest substantial declines in populations… across much of North America, and consequently strong cause for conservation concern.” The factors affecting these declines are unknown and, the report notes, “warrant further investigation.” However, some patterns have been observed—“factors exerting negative influences on populations are strongest along the Atlantic coast,” for example. Also: “More recent declines in western North America… appear to have occurred in concert with a prolonged drought.”

The Cornell Lab of Ornithology’s website paints a rather different picture, noting that the population of American Kestrels “increased greatly with historical deforestation of North America. No significant trend across North America, but some local increases and decreases.”

*     *     *

All of which adds up to… what? Like the BBS data, the Hawk Mountain Sanctuary Conservation Status Reports reveal population trends perhaps best described as “mixed.” Nowhere is there any indication that declining raptor numbers can be linked to the success of competing predators—including cats.

For George, the idea was nothing more than a hypothesis anyhow. But rather than put it to the test (ostensibly the role of scientists), Longcore, Dauphiné, Jessup, and the rest, have instead tried to elevate its status through nothing more than repetition—thereby betraying an agenda that has little to do with science at all.

Literature Cited
1. George, W., “Domestic cats as predators and factors in winter shortages of raptor prey.” The Wilson Bulletin. 1974. 86(4): p. 384–396. elibrary.unm.edu/sora/Wilson/v086n04/p0384-p0396.pdf

2. 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.

3. 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

4. Loyd, K.A.T. and DeVore, J.L., “An Evaluation of Feral Cat Management Options Using a Decision Analysis Network.” Ecology and Society. 2010. 15(4). http://www.ecologyandsociety.org/vol15/iss4/art10/

5. 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. www.pwrc.usgs.gov/pif/pubs/McAllenProc/articles/PIF09_Anthropogenic%20Impacts/Dauphine_1_PIF09.pdf

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. http://www.sciencedirect.com/science/article/B6V5X-48D39DN-5/2/d27bfff8454a44161f8dc1ad7cc585ea

7. Mosher, J.A., Accipiters, in Northeast Raptor Management Symposium and Workshop, B.A.G. Pendleton, Editor. 1989, National Wildlife Federation Scientific and Technical Series No. 13.: Syracuse, NY. p. 47–52.

8. Mosher, J.A., “Breeding Biology of Raptors in the Central Appalachians.” Raptor Research. 1982. 16(1): p. 18–24.

9. Jessup, D.A., “The welfare of feral cats and wildlife.” Journal of the American Veterinary Medical Association. 2004. 225(9): p. 1377-1383. http://avmajournals.avma.org/doi/abs/10.2460/javma.2004.225.1377

Docs’ Docs

The American Veterinary Medical Association (AVMA) recently made available online (via downloadable PDFs) several of its articles related to free-roaming cats/TNR. Although abstracts have been online for some time, access to the full text for these papers has generally required either a subscription to the Journal of the American Veterinary Medical Association or access to a subscribing library.

Among the articles that make up this edition of AVMA Collections are several I’ve referred to over the past few months—including two I’ve been quite critical of: one by Linda Winter, former director of the American Bird Conservancy’s Cats Indoors! campaign, and another by David Jessup.

The AVMA and Free-roaming Cats
Although “the AVMA encourages and supports actions to eliminate the problem of free-roaming abandoned and feral cats,” its policy regarding Free-roaming Abandoned and Feral Cats is, it must be said, ambivalent at best. The organization “neither endorses nor opposes appropriately managed cat colony programs,” for example. When it comes to the “treatment” of cats not in managed colonies, however, the AVMA is quite clear—as is the likely fate of these cats (despite the policy’s euphemistic language):

“The AVMA strongly supports reducing the number of unowned free-roaming abandoned and feral cats through humane capture (with placement in homes where appropriate) by local health departments, humane societies, and animal control agencies. All free-roaming abandoned and feral cats that are not in managed colonies should be removed from their environment and treated in the same manner as other abandoned and stray animals in accord with local and state ordinances.”

Another worrisome aspect of the AVMA’s policy is its matter-of-fact assertion that “these free-roaming abandoned and feral cats also represent a significant factor in the mortality of hundreds of millions of birds, small mammals, reptiles, amphibians, and fish” (the wording of which matches almost exactly a claim made by the American Bird Conservancy).

*     *     *

As with all large, politically-minded organizations, policy change at the AVMA is likely to be a slow process. Perhaps, though, by making this collection of articles available to the general public, they have, knowingly or not, given that process a nudge. Regardless of its intent—which seems to consider only a veterinary professional readership—the AVMA’s move may help foster a better-informed, more engaged debate among those outside the profession.

Parasite Lost

Until now, my posts have focused almost exclusively on wildlife impacts (real and otherwise) related to predation by cats, a topic I’ll be returning to soon enough. Over the past week or so, however, I’ve been researching the Toxoplasma gondii parasite (another subject that will keep me busy well into the future). As it turns out, there’s big news on the T. gondii front—though in this case, the “news” is actually two years old.

Toxoplasma gondii
Toxoplasma gondii
is found in many mammals and birds, but its definitive host—the animal in which the parasite reproduces—is the cat, both domestic and wild species. Cats pass the mature, infective form of the parasite in their feces—a process called “shedding oocysts.” T. gondii infection, or toxoplasmosis, in humans can be traced to “ingestion of oocyst-contaminated soil and water, from tissue cysts in undercooked meat, by transplantation, blood transfusion, laboratory accidents, or congenitally.” [1]

How often cats shed oocysts, and to what extent, is a complex issue—one I’ll save for later. For now, I will simply note that, in general, it is thought that most cats build up immunity to re-shedding oocysts (though exceptions have been documented in laboratory testing). [2] (For a concise overview of T. gondii’s prevalence in, and risks to, humans, download Toxoplasma gondii: Epidemiology, feline clinical aspects, and prevention.”)

T. Gondii, Cats, and Sea Otters
In recent years, T. gondii has been linked to the illness and death of marine life, primarily sea otters [2], thereby prompting investigation into the possible role of free-roaming (both owned and feral) cats. [3, 4] It’s generally thought that oocysts are transferred from soil contaminated with infected feces to coastal waterways by way of freshwater run-off. [4] And it’s also generally thought that domestic cats are the culprits—or at least it was.

As I was sifting through my growing pile of T. gondii studies, I was rather shocked to find this:

“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.” [4] (italics mine)

Let me explain. There are multiple strains of T. Gondii. Studies of southern sea otters from coastal California found that 36 of 50 otters were infected with the Type X strain. [5] In other words, 72% of the otters were infected with a strain of T. gondii that has yet to be traced to domestic cats.

Now, I’ll be the first to admit that these results are to be treated with caution—as Miller et al. note, “subsequent studies” are in order. For one thing, 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). In addition, this area of research is quite active—and, as this study illustrates, the results can be surprising. Future research intended to confirm or refute this work could just as easily take us off in another direction altogether.

That said, this is still big news. Nearly two years old now, however, it’s not exactly breaking news. So why is this the first I’ve heard about these important findings?

What’s the Story?
For some reason, Miller et al. downplay their findings. Worse, they confuse matters by going into detail about the estimated mass of “feline fecal deposition” created by domestic cats in the communities adjacent to their study site. Suddenly, the focus is back on domestic cats. Given the authors’ findings, I’m not sure how this is relevant, other than as background—previous assumptions being called into question by their results. Perhaps it’s merely the inevitable result of 14 co-authors (one of whom, it should be noted, is David Jessup, of whose work I have been critical in the past) collaborating on a single paper.

But I’m unwilling to give Longcore et al. the same benefit of the doubt. In their essay, Longcore et al. [6] dissemble to such an extent that readers are likely to come away missing the point entirely:

“The large quantity of waste from feral and free-roaming cats containing Toxoplasma oocysts [3, 7] and the correlation between freshwater runoff and toxoplasmosis in marine mammals [8] has led researchers to suspect domestic cats as the source of the infections, although further research is needed to determine the relative importance of native versus exotic felids as sources of this parasite [4].”

While technically correct, Longcore et al. gloss over the fact that, based on the very study they cite, “the relative importance of native versus exotic felids as sources of this parasite” might be something like three-to-one.

And it’s not as if these authors are unwilling to consider speculative findings—such as those by Baker et al. [9] and Hawkins [10]. Longcore et al. even take seriously the Wisconsin Study [11] and its findings that “aren’t actual data.” [12] And they leave out plenty, too—which in the case of the Miller et al. work, might have been a more honorable approach.

Something else they should have omitted:

“Felids, including feral and free-roaming cats, shed Toxoplasma oocysts that infect southern sea otters [8, 5], Pacific harbor seals, and California sea lions.” [6]

In fact, Conrad et al. examined just one harbor seal and one sea lion—and in both cases found the Type X strain of T. gondii. [5] Which, when combined with the results from Miller et al., suggests wild felids as the more likely source, rather than domestic cats.

These two studies not only contradict the specific claims made by Longcore et al., they also challenge the native-good/non-native-bad dichotomy that seems to be at the root of so many feral cat/TNR complaints.

*     *     *

I sent an e-mail to Melissa Miller, lead author of “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,” asking her to comment on my reading of the study. I have not yet received a response.

Literature Cited
1. Elmore, S.A., et al., “Toxoplasma gondii: epidemiology, feline clinical aspects, and prevention.” Trends in Parasitology. 26(4): p. 190-196.

2. Jones, J.L. and Dubey, J.P., “Waterborne toxoplasmosis—Recent developments.” Experimental Parasitology. 124(1): p. 10-25.

3. 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.

4. 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.

5. 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.

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. Dabritz, H.A., et al., “Detection of Toxoplasma gondii-like oocysts in cat feces and estimates of the environmental oocyst burden.” Journal of the American Veterinary Medical Association. 2007. 231(11): p. 1676-1684.

8. Miller, M.A., et al., “Coastal freshwater runoff is a risk factor for Toxoplasma gondii infection of southern sea otters (Enhydra lutris nereis).” International Journal for Parasitology. 2002. 32(8): p. 997-1006.

9. 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.

10. 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

11. 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

12. Elliott, J., The Accused, in The Sonoma County Independent. 1994. p. 1, 10.

Sanctuary In Name Only

Although Vox Felina was launched in April of this year, its origins can be traced back to 2007 and the town of Pahrump, Nevada. There, 748 cats were abandoned in the summer heat—left sick, starving, and dehydrated by the very people who claimed to be their rescuers. Were it not for the heroic efforts of Best Friends Animal Society and a tireless team of volunteers (local and from across the country), nearly all of those cats would have died.

Within the organization operating the Pahrump sanctuary—For the Love Of Cats and Kittens, or FLOCK—there was nothing but finger-pointing. Earlier this year, the case against FLOCK’s former board members was dismissed on a technicality—the result of the case having been badly botched from the outset by the Nye County District Attorney’s Office. Anybody familiar with the story knows of D.A. Robert Beckett’s incompetence and questionable judgment (e.g., in a six-hour period, Beckett once rolled two cars—one of which belonged to the county—resulting in a citation for DUI). Then, last week, The Wall Street Journal reported that Beckett’s under investigation for dipping into County funds.

All of this got me thinking—not of Beckett or the D.A.’s Office, but of FLOCK. The organization is still around (although I’m told the leadership has changed). And a few months ago there were reports—which I have been unable to confirm—that FLOCK might be establishing a new sanctuary, this time in neighboring Clark County.

Another FLOCK sanctuary would be a recipe for disaster, and not just because of that organization’s abysmal record. Many cat sanctuaries are overcrowded, underfunded, and—lacking any kind of contingency plan, as is often the case—prone to collapse. And they can be used to cover up institutional hoarding.

Sanctuaries as Alternatives to TNR?
Cat sanctuaries were among the topics discussed at the American Veterinary Medical Association’s 2004 Animal Welfare Forum, “Management of Abandoned and Feral Cats.” Among those suggesting that sanctuaries are a viable alternative to TNR were Linda Winter, former director of the ABC’s Cats Indoors! program:

“Cat sanctuaries, such as those run by Best Friends in Utah, Rikki’s Refuge in Virginia, the Humane Society of Ocean City in NJ, the CCC in California, the Delaware Humane Association in Delaware, and the Habitat for Cats Sanctuary in Massachusetts, keep cats sheltered, safe, and well fed; provide access to routine veterinary care; protect wildlife; and reduce health risks for cats and people. The ABC strongly supports sanctuaries for stray and feral cats as an alternative to TNR that is more humane to both cats and wildlife.” [1]

Former Chief of the U.S. Army Veterinary Corps, Paul Barrows, was another participant in favor of sanctuaries as an alternative to TNR:

“Whether adopted; placed in a confining sanctuary; judiciously used in research, training, or education; or euthanized, removal and not return seems to be the most responsible course of action.” [3]

David Jessup, Senior Wildlife Veterinarian with the California Department of Fish and Game, also weighed in with his own enthusiastic endorsement:

“Recently, another option has become available: enclosed sanctuaries where cats can live out their lives protected from weather and most injury. Large and well-known cat sanctuaries exist in Delaware, Massachusetts, New Jersey, New Mexico, Virginia, and several places in California. Others are being built and operated by individuals and organizations on small and moderate scales similar to other sanctuaries, as described by Winter. This is happening simply because people sense it is the right thing to do. Hopefully, we can all agree this is one thing that truly serves the welfare of both cats and wildlife.” [2]

However, this is the same article in which Jessup alleges—without so much as a single reference to support him—that there are “60–100 million feral and abandoned cats in the United States.” [2] Clearly, there isn’t nearly enough sanctuary space for the number of cats; in fact, sanctuaries are “another option” for only a tiny fraction of the stray, abandoned, and feral cats out there (even when more accurate estimates are considered).

Indeed, in their contribution to AVMA’s 2004 Animal Welfare Forum, Julie Levy and Cynda Crawford suggest as much: “most sanctuary programs that permanently house feral cats are filled to capacity almost immediately after opening.” [5]

And yet, years later, sanctuaries are still being marketed as alternatives to TNR. The ABC, for example, echoes Winter’s 2004 comments in its brochure “Managed” Cat Colonies: The Wrong Solution to a Tragic Problem, and in its short film Trap, Neuter, and Release: Bad for Cats, Disaster for Birds. In the film, produced last year, Steve Holmer, the ABC’s Director of Public Relations, suggests:

“A better solution is to trap, neuter, and remove feral cats, and then relocate them to enclosed cat sanctuaries or shelters, or to adopt them out to safe and comfortable homes.”

Sanctuaries: The Realities and Impacts
Alley Cat Allies opposes sanctuaries for feral cats, citing as concerns the inherent economic and medical challenges, as well as the overall lack of capacity—factors that too often prove insurmountable:

“A number of sanctuaries are forced to close their doors every year due to insufficient funds or an inability to properly care for the cats in the existing confined space.”

FLOCK was a case study, demonstrating in horrific detail that the sanctuary option—even when it’s available—is not always in the best interest of the cats. As one of my Best Friends contacts who was involved in the FLOCK clean-up effort told me, “I’ve got one of the Pahrump cats… I would rather see that cat back on the streets of Vegas, looking for food in Dumpsters, than be where they were at FLOCK.”

Indeed, the FLOCK story is all too familiar to people involved in such large-scale rescue efforts. Consider some of the more dramatic—and therefore “story-worthy”—incidents in recent years:

  • Voice of the Animals Sanctuary (Blanchard, ID, 2006)
    “Disaster responders from The HSUS, working alongside the Idaho Humane Society, found more than 400 cats, and a number of dogs, goats and chickens. Many were in extremely poor health and had to be euthanized.”

    “The animals were housed in and around nine dilapidated mobile homes on the property, according to published reports. Inside the trailers, investigators found that the walls were soaked in urine and the floors caked with feces and filth. Veterinarian and IHS executive director Dr. Jeff Rosenthal described the cats as all being ‘infested with fleas and ear mites. The majority were also in an emaciated state and suffered with upper respiratory illnesses, chronic diarrhea and abscesses,’ among other ailments.” (source: www.Pet-Abuse.com)

  • Tiger Ranch (Tarentum, PA, 2008)
    “All told, 380 living cats and 106 dead ones were discovered during a police raid at Tiger Ranch in Frazer Township, which owner and operator Linda Bruno billed as a pet adoption center and Hospice. Since then, many of the cats have died.”

    “‘It’s a death camp,’ said [Howard] Nelson [director of the Philadelphia-based Pennsylvania SPCA, which orchestrated the raid], speaking by cell phone as he helped gather emaciated and diseased cats crammed into trailers and other outbuildings across the 30-acre property. ‘I see cats that can’t walk, and dead cats in litter boxes and lying by food bowls.’” (source: www.Pet-Abuse.com)

  • Cats with No Name (Pine Grove Township, PA, 2009)
    “SPCA volunteer Beth Hall said the condition the 148 cats and 10 other animals were found in was unspeakable. ‘Our opinion is that it was heinous. In my opinion, it was like a kitty concentration camp,’ she said. ‘We just don’t understand.’ Mary Ellen Smith, president of the Steinert SPCA board, said the animals were subjected to ‘obvious cruelty and neglect.’”

    In addition, the couple responsible was “accused of stockpiling donated cat food and reselling some of it at auctions to finance drug binges while leaving dozens of animals to go hungry.” (source: www.Pet-Abuse.com)

  • 10th Life Sanctuary (LaBelle, FL, 2009)
    “The final statistics tell a story of success and sadness. The closure of the 10th Life Sanctuary represents one of the largest cat rescues in US history. A total of 110 cats were euthanized in the first days of medical triage due to critical medical illnesses, including 17 that were euthanized immediately following the unannounced inspection. Of the remaining 485 cats, 75 of the ferals were euthanized when new placements could not be found for them. This 15% euthanasia rate for the savable cats is in stark contrast to the vast majority of large-scale feline cruelty impoundments in which mass euthanasia is the most common outcome.” (source: Maddie’s Shelter Medicine Program, University of Florida)

*     *     *

To be clear, I’m not opposed to sanctuaries as such. Indeed, I’m a supporter of Best Friends and Shadow Cats Rescue. What I am opposed to is sanctuaries being oversold—generally to an audience that has no knowledge of such matters—as a viable alternative to TNR. To suggest anything of the sort is, at best, disingenuous. Sanctuaries are no more an alternative to TNR than zoos are to the protection of endangered species.

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

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. 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.

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. 2009. p. 205–219

5. 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.