Collisions, Predation, and Bird Populations

Masts of the Rugby Radio Station transmitter, Warwickshire, England. Courtesy of Wikimedia Commons and Sreejithk2000.

Recent research suggests that collisions with buildings and communication towers have no significant effect on bird populations. These findings raise additional questions about the often-implied connection between predation by free-roaming cats and declining bird numbers.

According to the American Bird Conservancy, 300 million to 1 billion birds are killed each year in “collisions with glass on buildings, from skyscrapers to homes.” As many as 50 million more are killed annually by communication towers.

Yet, according to a study published last September in the open-access, online publication PLoS ONE, “this conspicuous source of mortality has had no discernible effect on long-term population dynamics among North American landbirds.” [1]

“At worst,” suggest authors Todd Arnold and Robert Zink, conservation biologists from the University of Minnesota, “collision mortality could be described as an added burden for populations already in decline for other reasons.” [1]

Which would seem to be, if not good news for the folks at ABC, then at least news. (Even solutions “that can greatly reduce avian collision mortality at manmade structures,” warn the researchers, “will not halt population declines among North American migratory birds.” [1])

So, why is there no mention of this study—published nearly six months ago—on the ABC website?

I suspect it will never appear there—or in any ABC publication. And they’re certainly not going to mention it to the media—too many awkward questions about contradictory assertions, resource allocation, and the like. After all, this is an organization that prides itself on using “the best available science” to shape policy.

(To be clear: Arnold and Zink are not opposed to “the deployment of simple design solutions that can greatly reduce avian collision mortality at manmade structures,” [1] despite the rather dire results of their analysis.)

The Study
To better understand potential population-level impacts, Arnold and Zink compared “long-term records of avian mortality from communication towers and urban buildings… with population estimates and trend data from the North American Breeding Bird Survey.” [1] The relative vulnerability of various species (188 in the case of communication towers, 147 for buildings) was quantified by comparing the proportion of birds killed in collisions with towers and/or buildings with their proportion in the overall bird population.

Species with very high collision mortalities relative to their abundance were dubbed “super colliders,” while species with very low instances of collisions relative to their numbers were dubbed “super avoiders.”

The spread between the two extremes is astonishing. Bay-breasted warblers, for example, were found to be 236 times more likely to collide with towers than would be predicted by chance alone (but are nevertheless considered a species of Least Concern). Horned larks, on the other hand, are 688 times more likely to avoid the same towers.

Fascinating work! What caught my eye, though, was the authors’ suggestion that their analysis technique would be appropriate for assessing “many poorly quantified conservation threats [including] house cat predation.” [1]

Future (Hypothetical) Study
Curious, I contacted Arnold, asking him how one would go about conducting such a study. Surely, obtaining an accurate count of mortalities due to predation is far more complicated than tallying mortalities due to man-made structures (itself, no trivial undertaking).

In fact, the greatest challenge, suggests Arnold, is not the data collection or subsequent analysis.

“In order to do the scientific study that you asked about, it’s necessary to approach it objectively, and I’d worry that anybody tackling this issue would be in one camp or the other, and the study really demands an impartial referee. A possibly better alternative would be to get members of both sides to agree in a mediated discussion what would constitute a valid study of the issue, and how such a study would be designed, implemented, and interpreted.”

Fair enough. Still, though: if implementation and interpretation pose particular challenges, the design of the study is actually fairly straightforward. “To apply the approach that we used for tower and building collisions,” Arnold says, “you would need to assemble a large data set on what species of birds are killed by cats.”

“It would probably take a large network of citizen scientists to accumulate a database on species composition of cat-killed wildlife; they would need to be people who had frequent and regular access to one or more cats—so, cat owners, cat monitors, and cat stewards who would agree to participate on a long-term basis. It would be important that sampling wasn’t driven by spectacular events (e.g., a cat owner ignores several non-descript House Sparrows that their cat brings home, and only submits information when a colorful Northern Cardinal gets killed). Conversely, you’d need to worry about people who might report only the boring and common things and fail to report when a rare or well-loved bird is killed because they are ashamed or fear backlash from the bird-loving public.”

Proper identification of each species would, of course, be critical. This, says Arnold, could be done using digital photos or by collecting remains (a method often employed in predation studies [2] and [3] and [4]).

“The study would have to continue until several thousand birds had been identified to species (Bob Zink and I worked with data sets that were a minimum of about 5,000 dead birds). From the mortality records, one would first identify the species that were most vulnerable to cats by comparing their proportion in the cat-kill data to their expected proportion based on population estimates. So, say for example, that juncos and American robins were 5.2 and 3.2 percent of the mortality records, but only 1.3 and 1.6 percent of the total bird population, then they’d be 4 and 2 times more vulnerable to cats than expected by chance. Other species would be less vulnerable than expected by chance. This part of the study would identify which species of birds were most vulnerable to predation by cats, and a priori I’d expect to see that ground-feeding birds like juncos and robins were more vulnerable, as well as urban- and suburban-adapted birds like robins, starlings, chickadees, etc.”

As Arnold and Zink point out in their paper, “total body counts reveal little about relative mortality risk for each species”—a fact often overlooked or ignored by those trying to link predation by cats to declining bird populations. And so, “the final—but critical—step” in our hypothetical study, says Arnold, “is to ask: Does this mortality factor matter do bird populations?

“It obviously matters to the individuals that were killed, but given that 40–50 percent of the fall bird population is probably not going to be alive one year later, the focus here has to be on long-term population dynamics. And so, the final step would involve correlating the measure of vulnerability to cat predation from the first step with long-term population trends for these same species. If one finds that cat predation rates are not correlated with bird population trends, then it’s time to stop vilifying cats for bird declines (with the important caveat that it might still be important for one or two endangered/threatened species). If one finds that cat predation rates are negatively correlated with bird population declines, then it suggests that cats might be an important limiting factor of birds populations (with the important caveat that it might be due to some other unmeasured factor that is also correlated with cat predation).”

What We Already Know
Unfortunately, I’m in no position to undertake the study Arnold describes. And, in any case, am (unapologetically) in “one camp or the other.” (That said, I’d jump at the chance to be part of the aforementioned “mediated discussion.”)

On the other hand, there’s already plenty of research suggesting that predation does not necessarily result in population-level impacts. In The Domestic Cat: The Biology of Its Behaviour, for example, Mike Fitzgerald and Dennis Turner thoroughly reviewed 61 predation studies, concluding rather unambiguously: “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.” [5]

Also: it’s well-known that predators—cats included—tend to prey on the young, the old, the weak and unhealthy. Indeed, at least two research studies have investigated this phenomenon in great detail. In one, researchers comparing the fat reserves of birds killed by cats to those of birds killed through non-predatory events (e.g., collisions with windows or cars) found that “mean fat scores evident in the cat-killed birds… were sufficiently low that these individuals were likely to have had poor long-term survival prospects.” [6]

In another study, researchers found that songbirds killed by cats tend to have smaller spleens than those killed through non-predatory events, leading them to conclude that “avian prey often have a poor health status.” [7]

As the UK’s Royal Society for the Protection of Birds notes: “It is likely that most of the birds killed by cats would have died anyway from other causes before the next breeding season, so cats are unlikely to have a major impact on populations.” [8]

(Frank Gill makes this very point in the third edition of Ornithology: “With some conspicuous exceptions… predators don’t limit or regulate the bird populations on which they prey. Instead, they take weak, sick, and young birds, many of which are part of the surplus that exceeds locally limiting food supplies.” [9] When it comes to cats, however, Gill considers “managed feral cat colonies [to be] potentially a serious threat to local bird populations.”)

•     •     •

Granted, the studies referenced above are no substitute for the one Arnold describes. And I don’t expect ABC to “stop vilifying cats for declining bird populations” anytime soon.

Nevertheless, Arnold and Zink’s findings ought to make it more difficult for ABC (or any other organization blaming cats for declining bird populations) to continue using cats as scapegoats. After all, even using the figures cited by ABC, it seems quite likely that collisions with buildings and communication towers are responsible for more bird deaths than are cats.* And the man-made structures are taking out healthy individuals.

Of course, as Arnold notes in his e-mail, bird species vulnerable to man-made structures may not be vulnerable to predation by cats, and those vulnerable to predation by cats may not be vulnerable to collisions. Still, taken together, all of this research begs the question: If building- and tower-collisions aren’t having population-level impacts, how likely is it that free-roaming cats are?

Which is exactly what I asked Darin Schroeder, ABC’s Vice President of Conservation Advocacy, and Steve Holmer, their Director of the Bird Conservation Alliance. That was three weeks ago.

*According to The American Bird Conservancy’s Guide to Bird Conservation, “532 million birds [are] killed annually by outdoor cats.” [10] Though far less than the “one billion birds” sometimes cited by TNR opponents, [11] ABC’s “estimate” is based on some dubious assumptions.

Thanks to my friends at Alley Cat Allies for bringing Arnold and Zink’s paper to my attention.

Literature Cited
1. Arnold, T.W. and Zink, R.M., “Collision Mortality Has No Discernible Effect on Population Trends of North American Birds.” PLoS ONE. 2011. 6(9): p. e24708.

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

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

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

5. 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.

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

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

8.  n.a. (2011) Are cats causing bird declines? Accessed October 26, 2011.

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

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

11. 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.

Portland Tribune Letter to the Editor

My sincere thanks to the folks at the Portland Tribune for publishing my letter to the editor, written in response to their January 19 story, “Fowl play: birders clash over wild-cat spaying.”

Why doesn’t anybody pin down Steve Holmer or anybody else at the American Bird Conservancy when they make their indefensible claims? Hundreds of millions of birds each year? Where’s the science to support such an assertion?

Aggregate predation figures, such as those routinely used by the ABC (as well as the U.S. Fish and Wildlife Service, and others), can typically be traced to small—often flawed—studies, the results of which are subsequently extrapolated from one habitat to another, conflating island populations (where the presence of cats can have dire consequences) and those on continents, combining common and rare bird species and so forth.

Something else to keep in mind: predators—cats included—tend to prey on the young, the old, the weak and unhealthy. As the UK’s Royal Society for the Protection of Birds notes: “It is likely that most of the birds killed by cats would have died anyway from other causes before the next breeding season, so cats are unlikely to have a major impact on populations.”

All of which raises serious doubt about the implied connections—both direct and indirect—between predation and population impacts. Indeed, there is plenty of scientific evidence to suggest that such a connection is relatively rare and highly context-specific.

While I’m pleased to see [conservation director of the Audubon Society of Portland] Bob Sallinger supporting trap-neuter-release, he makes essentially the same error when he says, “There’s no question that outdoor cats are harming the local wild bird population.” Rehab intakes provide, at best, a soda-straw view of the world. It’s a bit like making conclusions about a community’s human population based on one’s experience as an ER nurse.

What’s truly bizarre about ABC’s “mayors letter” is their suggestion that policies prohibiting trap-neuter-release and the feeding of outdoor cats would, as ABC’s media release puts it, “stop the spread of feral cats.” Again, where’s the science to support such a ridiculous claim? That’s easy: it doesn’t exist; indeed, the inevitable result of such policies is, contrary to ABC’s assertion, more cats.

For years now, ABC has been promoting erroneous and misleading information (e.g., baseless feral cat population numbers, exaggerated/erroneous predation rates, etc.) in their tireless effort to vilify free-roaming cats. No organization has been more effective at working the anti-trap-neuter-release pseudoscience into a message neatly packaged for the mainstream media, and eventual consumption by the general public. Their “mayors letter” is just their latest attempt to fuel the witch-hunt.

Something else not mentioned here—and something ABC’s certainly not going share with the mayors on their mailing list: we can’t kill our way out of the “feral cat problem.”

Mark Kumpf, former president of the National Animal Control Association, refers to the traditional trap-and-kill approach as “bailing the ocean with a thimble.” “There’s no department that I’m aware of that has enough money in their budget to simply practice the old capture-and-euthanize policy; nature just keeps having more kittens.”

I agree that the feral cat population is, as ABC’s Darin Schroeder puts it in his letter, a human-caused tragedy, but let’s be clear: ABC is part of the problem, not part of the solution. Their recent letter is merely a sign of desperation – the result of having neither public opinion nor science on their side.

Crazy Is As Crazy Does

An article in The Atlantic describes fascinating research into the effects of Toxoplasma gondii infection, but what role do domestic cats really play?

Although we’re not even halfway through February, an article in the March issue of The Atlantic is already getting a lot of attention. But with a title like “How Your Cat Is Making You Crazy,” that’s no surprise. (Don’t get me wrong: the article is a great read.)

What is surprising is that the story hasn’t been picked up by the American Bird Conservancy or, more likely, The Wildlife Society.

Not yet, anyhow. Surely, it’s only a matter of days before ABC, TWS, and others (mis)use the article to stir up their witch-hunt against free-roaming cats. A careful read, however, suggests such a move would be both premature and misguided (as if that makes any difference).

At the center of “How Your Cat Is Making You Crazy” is the intriguing research* of Jaroslav Flegr, an evolutionary biologist at Charles University in Prague, who’s spent the past 20 years or so exploring the possible connections between infection with Toxoplasma gondii, a parasite cats can pass in their feces, and human behavior.

“Healthy children and adults,” explains writer Kathleen McAuliffe, “usually experience nothing worse than brief flu-like symptoms before quickly fighting off the protozoan, which thereafter lies dormant inside brain cells—or at least that’s the standard medical wisdom.”

But if Flegr is right, the ‘latent’ parasite may be quietly tweaking the connections between our neurons, changing our response to frightening situations, our trust in others, how outgoing we are, and even our preference for certain scents. And that’s not all. He also believes that the organism contributes to car crashes, suicides, and mental disorders such as schizophrenia.

As I say, it’s just a matter of time—and not much of it, I suspect—before TNR opponents jump all over this, shaping it to fit their (tired) message.

I expect to see the lengthy quote from Joanne Webster, a parasitologist at Imperial College London, parsed very carefully, for example. Webster and her colleagues discovered that Toxo-infected rats are actually attracted to cat urine, a phenomenon they dubbed “fatal feline attraction.” Commenting on Flegr’s research, Webster is, in McAuliffe’s words, “more circumspect, if not downright troubled.”

I don’t want to cause any panic. In the vast majority of people, there will be no ill effects, and those who are affected will mostly demonstrate subtle shifts of behavior. But in a small number of cases, [Toxo infection] may be linked to schizophrenia and other disturbances associated with altered dopamine levels—for example, obsessive-compulsive disorder, attention-deficit hyperactivity disorder, and mood disorders. The rat may live two or three years, while humans can be infected for many decades, which is why we may be seeing these severe side effects in people. We should be cautious of dismissing such a prevalent parasite.

I imagine those first two sentences will be among the first to be dropped from any ABC or TWS reference to the article. As will this response from Robert Sapolsky, a professor of biology and neurology at Stanford:

…I’m not too worried, in that the effects on humans are not gigantic. If you want to reduce serious car accidents, and you had to choose between curing people of Toxo infections versus getting people not to drive drunk or while texting, go for the latter in terms of impact.

Infection in Humans
“Humans,” explains McAuliffe, “are exposed not only by coming into contact with litter boxes, but also, he found, by drinking water contaminated with cat feces, eating unwashed vegetables, or, especially in Europe, by consuming raw or undercooked meat. According to the Centers for Disease Control and Prevention, the infection rate in the U.S. among those 12 and older is estimated to be 22.5 percent.

And while Toxoplasmosis “can come from cats,” the CDC points out that “people are more likely to get it from eating raw meat or from gardening.”

Nowhere in McAuliffe’s article does she mention the proportion of people infected through contact with cat feces, as compared to those infected from eating raw or undercooked meat. For the purposes of Flegr’s work, the source is largely immaterial. (And, virtually impossible to know, I gather—which would explain why I’ve never seen so much a guess.)

Infection in Cats
In the infamous “University of Nebraska-Lincoln paper,” published in 2010, the authors report—correctly, according to their source—that “most feral cats (62 percent to 80 percent) tested positive for toxoplasmosis.” [1] Trouble is, testing positive—seroprevalence—is simply not a useful measure of their ability to infect other animals or people.

“Most cats only shed oocysts for about one week in their life” (Note: The Atlantic suggests a three-week duration, as noted below) and seroconvert afterward. [2] “Thus, it is a reasonable assumption that most seropositive cats have already shed oocysts.” [2] “Testing positive,” in this case, is nothing more than the detection of antibodies resulting from seroconversion. Furthermore, because “most seronegative cats shed millions of oocysts after exposure to T. gondii… seropositive cats are likely to be less of a public health risk than seronegative cats.” [3]

Environmental Contamination
Because Flegr’s work doesn’t involve environmental contamination, McAuliffe only touched on the subject (“the parasite is typically picked up from the soil by scavenging or grazing animals—notably rodents, pigs, and cattle…”). For many TNR opponents, however, this is a hot topic—as some have suggested a direct connection between the presence of domestic cats and toxo-related infections in other animals, primarily land and marine mammals. (See, for example, my post from May 17 of last year.)

As a recent paper reports, bluntly: “Cats are the definitive host: the disease only occurs when cats are present.” [4] In fact, this claim is contradicted by a number of studies:

  • High levels (75 percent) of congenital transmission of T. gondii, for example, in a “wild population of mice,” led UK researchers to conclude “that this phenomenon might be more widespread than previously thought.” [5] Infections in sheep also point to congenital transmission, which “may be more important than previously considered.” [6]
  • The “high incidence of T. gondii found, among others, in free-living ruminants suggests a possibility of other, so far unknown, paths of transmission of this protozoan.” [7] “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.” [7]
  • Of particular interest are studies in the Arctic, where the prevalence of T. gondii infection in arctic foxes, Svalbard reindeer, sibling voles, walruses, kittiwakes, barnacle geese, and glaucous gulls “indicates that infection by oocysts is not an important mode of transmission on Svalbard.” [8] “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.” [8] Researchers studying infection rates in polar bears concluded: “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.” [9]

In the Spring 2011 issue of The Wildlife Professional’s special section, “The Impact of Free Ranging Cats,” the authors argue: “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.” [10] What the fail to acknowledge is that the most common type of T. gondii found to be infecting sea otters is the Type X strain, [11] which has yet to be traced to domestic cats, [12] or that “dual infections of T. gondii and S. neurona were more frequently associated with mortality and protozoal encephalitis than single infections, indicating a role for polyparasitism in disease severity.” [13]

Now What?
So, what are we to make of all this?

Or, as McAuliffe poses the question: “Given all the nasty science swirling around this parasite, is it time for cat lovers to switch their allegiance to other animals?”

Even Flegr would advise against that. Indoor cats pose no threat, he says, because they don’t carry the parasite. As for outdoor cats, they shed the parasite for only three weeks of their life, typically when they’re young and have just begun hunting. During that brief period, Flegr simply recommends taking care to keep kitchen counters and tables wiped clean. (He practices what he preaches: he and his wife have two school-age children, and two outdoor cats that have free roam of their home.)

Certainly, there’s still plenty we don’t know about T. gondii. A May 2011 article in Scientific American, for example, concedes simply: “The exact link between T. gondii and psychiatric diseases is tantalizing but remains murky.” [14]

Most telling of all may be the reaction of the pharmaceutical industry. Or, lack of a reaction, to be more precise. “Until solid proof exists that Toxo is as dangerous as some scientists now fear,” observes McAuliffe, “pharmaceutical companies don’t have much incentive to develop anti-Toxo drugs.” And if Big Pharma doesn’t think there’s money to be made here, how worried should we really be?

•     •     •

If history is any indication, “How Your Cat Is Making You Crazy” will be badly misrepresented by some TNR opponents, used to further vilify free-roaming cats as a public health threat. Not that they’ll offer anything in the way of a solution, of course—just more fear-mongering.

Now, if ABC, TWS, and all the rest are really concerned about toxo, why not propose a meat-free diet? OK, now that’s crazy.

*As opposed to, say, the unconvincing claims attempting to link T. gondii to brain cancer, published in a paper last summer. As expected, TWS took the bait.

Literature Cited
1. Hildreth, A.M., Vantassel, S.M., and Hygnstrom, S.E., Feral Cats and Their Management. 2010, University of Nebraska-Lincoln Extension: Lincoln, NE.

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.

3. Vollaire, M.R., Radecki, S.V., and Lappin, M.R., “Seroprevalence of Toxoplasma gondii antibodies in clinically ill cats in the United States.” American Journal of Veterinary Research. 2005. 66(5): p. 874–877.

4. Duffy, D.C. and Capece, P., “Biology and Impacts of Pacific Island Invasive Species 7. The Domestic Cat (Felis catus).” Pacific Science. 2011. 66(2 (Early View)): p. 000–000.

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.

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

7. 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.

8. 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.

9. 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.

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

11. 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.

12. 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.

13. 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.

14. Koch, C., “Protozoa Could Be Controlling Your Brain.” Scientific American. 2011.

We Report, You Decide

According to a story in last Saturday’s Akron Beacon Journal, the American Bird Conservancy “estimates there are 90 million wild cats nationwide, part of a free-roaming population that is killing more than a half billion birds annually.”

Beacon Journal readers unfamiliar with ABC’s free-roaming cats “message” probably assumed those “estimates” correspond to real numbers, give or take a few million. For the rest of us—those who know the organization’s line of misrepresentations, inaccuracies, and flat-out fabrications all too well—such “estimates” are taken about as seriously as the claims accompanying wee-hour infomercials.* Indeed, their greatest value, more often than not, is as fodder for another round of Feral Cat Witch-hunt Bingo.

And George Fenwick, ABC’s president, did not disappoint in this regard.

“Our read is really quite clear that free-roaming cats—that includes TNR cats—are proliferating. They are expanding horrifically and the data that we have, that’s been peer reviewed and published, makes it quite clear that there is no evidence that TNR works.”

In fact, what seems to be expanding horrifically is ABC’s witch-hunt—resulting in increasingly desperate, indefensible claims. All of which I pointed out—with quotes and citations from several peer-reviewed, published articles—to Beacon Journal reporter Kathy Antoniotti.

She was, I think it’s safe to say, unimpressed.

“It is my job to make sure that both sides are represented in any story I do,” she told me via e-mail, “and Mr. Fenwick has impressive credentials as a scientist.”

“I realize everyone thinks they are right on this issue. But as a reporter I have an obligation to present both sides of the argument, not to interrupt the information with my personal beliefs.”

Both Sides
Now, in Antoniotti’s defense, she did interview Julie Levy, Maddie’s Professor of Shelter Medicine in the University of Florida’s College of Veterinary Medicine, Alley Cat Allies president Becky Robinson, as well as individuals from nearby One of a Kind Pet Rescue and Dancing Paws Wellness Center for the piece. And, unlike so many reporters, she didn’t frame the debate as “the respected scientists” vs. “the crazy cat ladies.”

Antoniotti also refused to disclose the location of the three managed colonies she refers to in the story’s lede (a professional courtesy not to be taken for granted).

But, still: does her obligation really end with the representation of both sides?

In my reply to her e-mail, I asked Antoniotti if she’d be satisfied with presenting “both sides” of the climate change debate. What about intelligent design, or the MMR vaccine/autism “controversy”?

“I have great respect for journalists,” I continued, “but fully expect that their role is not to present both sides, but to get at, to whatever extent possible, the truth of a story (which means questioning even those with ‘impressive credentials’).”

Why didn’t Antoniotti at least ask Fenwick what ABC proposes instead of TNR—a perfectly reasonable follow-up? (Her failure to do so does not bode well for any subsequent follow-ups in response to ABC’s standard talking points about sanctuaries, the various risks to outdoor cats, and so forth.)

Or, how prohibiting TNR and the feeding of outdoor cats would, as ABC claims in its October 2011 letter to big-city mayors—to which Antoniotti refers in her story—“stop the epidemic spread of feral cats that threaten national bird populations as well as scores of other wildlife.”

Antoniotti was quick to respond, but never addressed these questions, suggesting simply, “we will have to agree to disagree.” She also explained that she’d “spent several days on this article and more than a month on research, when time allowed.”

Well, OK. I, more than most people, understand the enormous challenges of wading through the various claims, published studies, government reports, etc. in search of the truth (generally without the added pressure of deadlines or space constraints). A single report leads to half-a-dozen important articles, each of which leads to others—some of which are easily obtained, while others require connections to a network of libraries and subscription-only databases. Before you know it, you’ve forgotten what you were after in the first place.

On the other hand, some claims are remarkably easy to debunk—such as Antoniotti’s assertion, attributed to the Humane Society of the United States, that, “in seven years, one female cat and her offspring theoretically can produce 420,000 cats.” The Wall Street Journal’s “Numbers Guy,” Carl Bialik, untangled this one more than five years ago:

“Hundreds of media reports have repeated that startling stat… This is one feline number that has nine lives. Though no one I spoke to could say for sure where it comes from, and no one defended it, the myth of the precociously procreating cat has lived on as an advocacy tool for spaying cats for at least 18 years.”

See that? Dig into the claim a little bit, and it turns out there aren’t actually “two sides” after all.

Return to Akron
Meg Geldhof, a veterinarian with One of a Kind Pet Rescue, told Antoniotti that she doesn’t necessarily think TNR conflicts with ABC’s “goal… to reduce the number of feral cats.”

“If we do nothing, then we will continue to have an overpopulation of cats. This actually reduces them. And, isn’t that what they want?”

Good question. What exactly does ABC want? Absolutely no outdoor cats is the obvious the answer. And how do we get there? What’s to be done with the millions of stray, abandoned, and feral cats—90 million of them, if ABC is to be believed?

Here’s a hint: the answer is not sanctuaries. (Actually, I speculated about four possible scenarios in a post last month.)

So why is the press so reluctant to pin down ABC on this issue? For Antoniotti and the Beacon Journal, in particular, this was a missed opportunity. Since Akron approved its “cat ordinance” nearly 10 years ago, it’s become a hotspot in the TNR/free-roaming cat debate.

Ordinance 332-2002 made it illegal for cats to be “off the premises of the owner and not under restraint by leash, cord, wire, strap, chain, or similar device or fence or secure enclosure adequate to contain the animal.” In addition, it became the duty of Akron’s Animal Control Wardens to “apprehend” and “impound” any cats “running at large.”

All of which would, it seems, make the city a kind of poster-child for ABC and its Cats Indoors! program (not quite the ideal fully realized, obviously, but a significant step in what the organization views as the right direction). So, why isn’t Fenwick singing the praises of Akron’s forward-thinking policymakers, bragging about the area’s soaring population of birds now that cats are Public Enemy #1, and so forth? (ABC has, after all, been claiming Akron’s decision as a victory since at least 2004. [1])

Because there are no such success stories, would be my guess.

Now there’s something Beacon Journal readers ought to know about. And, how many cats have been rounded up and killed over the past 10 years as a result of the ordinance. Last year, one of Antoniotti’s colleagues at the paper reported on Summit County Animal Control’s 2010 adoption numbers (“More than 1,925 cats and dogs were adopted last year through the county—the largest number in at least the past seven years. Slightly more cats—986—were adopted than dogs.”), but the story never mentioned the number of pets that don’t make it out the front door. (When I asked Animal Control Manager Christine Fatheree about the agency’s intake, redemption, adoption, and “euthanasia” figures I was told: “These records were destroyed per our records retention schedule and no longer available.”)

Readers (and, since the Beacon Journal is now published online, this audience extends far beyond Summit County) might also like to know how the city’s policy has affected the population of free-roaming cats in the area—assuming, of course, it has. In short: what return have Akron taxpayers gotten for their investment?

Like all controversial stories, such ambitious journalistic undertakings would have (at least) two sides to tell. But the job doesn’t end there. Readers—many of whom are in-the-trenches stakeholders in the debate—expect and deserve better.

* I suspect that 90 million figure is derived, more as a matter of convenience than anything else, from a 2003 paper by Levy, Gale, and Gale, in which the authors write: “The number of unowned free-roaming cats in the United States is unknown, but is suspected to rival that of pet cats (73 million in 2000).” [2] These days, the number of pet cats is estimated to be 86.4 million, according to the 2011–2012 American Pet Products Association National Pet Owners Survey. Now, it’s quite a leap to suggest that for every additional pet cat acquired over the past 12 years in the U.S., there has been a one-cat increase in the free-roaming population—assuming two populations were more or less identical in 2000. Animal People’s Merritt Clifton estimated (also in 2003) 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.” [3] Later that same year, using roadkill data as a guide, Clifton suggested, “the U.S. feral cat population may have been reduced to as few as five million.” [4] “Since then,” Clifton tells me via e-mail, “the numbers suggest to me that the U.S. feral cat population has been flat, at about 6.5 million in winter, 13–16 million in summer.”

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

3. Clifton, M. (2003) Where cats belong—and where they don’t. Animal People.

4. Clifton, M. (2003) Roadkills of cats fall 90% in 10 years—are feral cats on their way out? Animal People.