Posts tagged with Lower Keys marsh rabbit

Key Lie Kitties

7 Mar 2013

It was easy to miss,* what with all the media attention devoted to the Smithsonian/USFWS’s “killer cat study,” published less than 24 hours later, but on January 28th, the Florida Keys National Wildlife Refuges Complex (managed by USFWS) released the Florida Keys National Wildlife Refuges Complex Integrated Pest Management Plan. Regular readers will recall that the draft version, released two years earlier, proposed the roundup of any free-roaming cats found on Refuge lands, but failed to offer any evidence whatsoever in terms of their estimated numbers, location, or diet.

In other words, evidence that the cats are the threat USFWS claims they are.

Two years later, that hasn’t changed. Indeed, there’s actually more to object to, not less. Read more

Cat Management Plan Reads Like Fiction

14 Apr 2011

In her recent attempt to “respond to recent comments and misinformation voiced by concerned citizens,” Anne Morkill, Refuge Manager for the Florida Keys National Wildlife Refuges, misrepresented both the rationale for, and implications of, the U.S. Fish and Wildlife Service’s indefensible Predator Management Plan. My response to Morkill’s opinion piece was published in today’s Upper Keys Free Press (download 15.4 MB PDF) (p. 43) under the headline “Cat management plan reads like fiction”:

I’d like to challenge some of the assertions made by Anne Morkill in her recent letter (“Refuges, animal advocates have common goal,” March 30), beginning with her suggestion that the impact of free-roaming cats on the Keys’ wildlife is well understood. In fact, the rationale presented by the U.S. Fish and Wildlife Service in its Florida Keys National Wildlife Refuges Complex Integrated Predator Management Plan/Draft Environmental Assessment (download PDF) demonstrated quite clearly that the organization lacks the necessary understanding (e.g., estimates of population size, range, diet, etc.) to begin “managing” cats on or near the refuges.

Given the fact that the USFWS has been struggling with this issue for years (at taxpayer expense, of course), one might expect a better foundation of knowledge from which to proceed (again, at taxpayer expense).

Morkill is quick to brush aside allegations that wildlife impacts have “been overstated and the science is flawed,” but offers little in the way of details. She notes the obvious—that cats do kill birds, small mammals and so forth—but says nothing about the extent of such predation or its impact on those populations of greatest concern (e.g., the Lower Keys marsh rabbit and Key Largo woodrat, etc.). And her mention of “popular literature” as a legitimate source for such evidence—a reference, I assume, to Jonathan Franzen’s latest novel, Freedom, in which the author (who sits on the board of the American Bird Conservancy) gives voice to his own opinions about cats and birds through one of his characters—is enough to erode any credibility she may have had on the subject.

On the other hand, much of the “justification for action” presented by USFWS in its Predator Management Plan is itself a kind of fiction. To support their claim that free-roaming cats have been a major cause of 33 extinctions around the world, for example, USFWS references studies of species that simply aren’t extinct. And, among the “evidence” of island extinctions are studies that—in addition to having nothing to do with extinctions—were not conducted on islands (e.g., rural Wisconsin, the small English village of Felmersham, etc.).

USFWS claims that free-roaming cats kill at least one billion birds every year in the U.S., but provides virtually nothing in the way of support. Indeed, one the three articles referenced—published in a birding magazine—is about defending one’s garden from neighborhood cats (“… 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.”). Another article cited by USFWS isn’t about cats at all. Or even invasive animals. It’s about invasive plants.

For USFWS to include such egregious errors in its Predator Management Plan (and there are plenty more, as I’ve documented in my comments to USFWS) suggests carelessness, clearly, but also a disregard for the public they are supposed to serve.

Had USFWS been more diligent in its review of the science, its plan would have addressed the risk of removing free-roaming cats from the Keys. If the agency were successful in removing the cats (unlikely, given their poor track record), the population of black rats would likely skyrocket—and decimate the very populations of native birds, mice and rats USFWS is trying to protect. As would the use of rodenticides that they would use ordinarily to control the population of rats. This phenomenon is well documented in the scientific literature, yet USFWS fails to acknowledge even the possibility in the Keys.

And they fail to acknowledge what’s involved in “successful” removal efforts. On Marion Island, located in the sub-Antarctic Indian Ocean, it took 19 years to eradicate something like 2,200 cats—using disease, poisoning, intensive hunting and trapping, and dogs. This, on an island that’s only 115 square miles in total area (slightly smaller than the combined area of the Keys), barren and uninhabited. The cost, I’m sure, was astronomical.

USFWS has a much more difficult task on its hands, obviously, though one would never guess this was the case reading through its Predator Management Plan.

And finally, a few comments about Morkill’s claim that “the service will not kill any cats.” Does she really think readers won’t pick up on the game she’s playing? If USFWS goes through with its plan, as proposed, it’s quite likely that many cats will end up dead. Does it matter that the dirty work will be done by Monroe County animal control shelters, rather than USFWS? As Morkill points out, the shelters “will be responsible for choosing the best future for the cats,” which, she adds, “may be adopted by individuals or groups that can provide long-term care.”

I asked Connie Christian, executive director of the Florida Keys SPCA, about this issue earlier this year, and she told me, “We do not have an outlet for feral cats that are brought to us without a request for return.” In other words, that “best future” Morkill refers to is—almost certainly—no future at all.

Like Morkill, I “agree that this is a people problem.” Unfortunately, she missed the irony in her comment: some of the people at the heart of the problem are right there at USFWS.

Best Available Science?

1 Mar 2011

After a while, I suppose, such things will no longer surprise me.

A couple weeks ago, the American Bird Conservancy released a statement in support of the Florida Keys National Wildlife Refuges Complex Integrated Predator Management Plan/Draft Environmental Assessment proposed by the U.S. Fish and Wildlife Service (USFWS):

“American Bird Conservancy, the nation’s leading bird conservation organization, and 27 additional science and conservation organizations have signed a letter to the Florida Keys National Wildlife Refuge supporting their plans to remove cats and cat feeding stations found on refuge lands in the Keys because of the harm they are causing to birds and other wildlife, including endangered species.”

No surprise there, really. It’s the following paragraph that caught my eye:

“The U.S. Fish and Wildlife Service deserves credit for bringing the best available science to bear on the management of exotic predators inhabiting National Wildlife Refuge lands regardless of the emotional aspects of the issue,” said Steve Holmer, Senior Policy Advisor for American Bird Conservancy. “Given the overwhelming evidence of harm to native birds inhabiting and migrating through the Keys, this predator management plan offers hope for healthier environment.”

“Best available science”? Are we talking about the same document here?

Granted, this is Steve Holmer—the same guy who, a year ago, told the Los Angeles Times that there are 160 million feral cats in the U.S. (a figure he arrived at by “reinterpreting” the already inflated figure proposed by Dauphine and Cooper).

In other words, consider the source.

Among the letter’s highlights (the letter itself doesn’t seem to be available, which is a shame, as I’m very interested in knowing which other “science and conservation organizations” are supporters):

“…cat predation accounted for 50 percent and 77 percent of mortality of two endangered species—the Lower Keys Marsh Rabbit and the Key Largo Woodrat.”

Lower Keys Marsh Rabbit
ABC’s claim about cats being responsible for half the mortality of marsh rabbits doesn’t actually correspond with what’s in the USFWS plan:

“Free-roaming domestic cat predation accounted for 50 percent of adult Lower Keys marsh rabbit mortality during radio telemetry studies and was cited as the largest factor limiting their population viability in the 1990s (Forys and Humphrey 1999).” [1]

During her PhD dissertation work, Elizabeth Forys’ found that 13 of 24 rabbits monitored over the course of her research were killed by cats, [2] findings she described four years later (in the paper cited by USFWS) this way:

“Twenty-seven (18 M, 9 F) of the 43 radiocollared individuals died during our 2.5-year study. Domestic cats killed the most marsh rabbits (53 percent of all mortality), killing nearly an equal number of both juvenile and adult marsh rabbits.” [3]

ABC misrepresents both Forys’ work and the USFWS plan by transforming those 13 marsh rabbits into “50 percent of mortality of [this] endangered species.” And this is too straightforward to be an accident.

For what it’s worth, this has been done before.

Impact of Cats on Marsh Rabbits
The Multi-Species Recovery Plan (MSRP) for South Florida, published in 1999 by USFWS, refers repeatedly to Forys’ work, noting, for example:

“Although habitat loss is responsible for the original decline of the Lower Keys marsh rabbit, high mortality from cats may be the greatest current threat to the persistence of the Lower Keys marsh rabbit [4].”

The report’s authors alternate between concessions and allegations, the latter of which are based on what can only be considered—even in the most generous light—circumstantial evidence. They acknowledge, for instance, that “a detailed study of cat diets in the Keys has not been conducted,” but then point out that “rabbits were the largest component of feral cat diets in several studies that have been conducted elsewhere (Jones and Coman 1981, Liberg 1985).” [5]

Let’s set aside for the moment the debate about whether or not two is considered “several” (and the fact that they got the year wrong on the Liberg study). Where exactly were those studies conducted? “Victorian Mallee, Kinchega National Park in western New South Wales, and the Victorian eastern highlands” [6] and “Revinge area in southern Sweden.” [7]

None of which, it’s safe to say, could be mistaken for the Florida Keys.

USFWS also acknowledges that “the exact extent [of predation by cats] cannot be determined,” though they imply that it must be increasing: “the number of cats present in the Lower Keys has increased over the past 20 years with the increase in the residential population.” [5]

(In fact, a number of studies have shown that cats will shift their “preferences” according to prey availability [see, for example, the review in 8]. Indeed, this was the case in the study from southern Sweden cited by USFWS: “Wild rabbits were the most important prey, and cats responded functionally to changes in abundance and availability of this prey.” [7])

The less common the rabbits, the less likely they are to fall prey to free-roaming cats.

Telling Stories
Somewhere along the line, though, the marsh rabbit story began to change.

An article in The Key West Citizen describing USFWS’s 2007 effort to round up cats in the Keys [9, 10] is a clear reference to—and equally clear misrepresentation of—Forys’ work:

“According to a 1999 U.S. Fish and Wildlife report, feral cats have killed 53 percent of marsh rabbits in the Lower Keys.” [9]

Contributors to the 2008 South Florida Environmental Report claim, “feral cats… have contributed to a 50 percent decline in populations of Hugh Hefner’s rabbits (Sylvilagus palustris hefneri, an endangered subspecies of marsh rabbit named for Hefner’s contributions to their research) on Big Pine Key (CNN.com, accessed May 20, 2007).” [11] I was unable to find anything at the CNN site, but suspect the story was nothing more than a pick-up of the story that ran in The Key West Citizen. (Florida residents will no doubt take great comfort in knowing that the South Florida Water Management District, publisher of the report, is unwilling to look any further than CNN.com for its science.)

In the 2009 book Invasive Species: Detection, Impact and Control, the story is much the same:

“[cats] have been a factor in the 50 percent decline in populations of the endangered Lower Keys marsh rabbit (Forys and Humphrey 1999).” [12]

In fact, Forys and Humphrey have little to say about the declining population:

“During the 1970s and 1980s, a period of intense habitat destruction, a decline in marsh rabbits was reported (Lazell 1984).” [3]

And Lazell? Nothing at all about the marsh rabbit population. I did, however, find this interesting:

“In 1980 I live-trapped five specimens on Lower Sugarloaf Key under Florida Game and Fresh Water Fish Commission (FGFWFC) permit 28. Three were prepared as skins and skeletons; two were released after physiological studies (Dunson and Lazell, 1982).” [13]

Not that Lazell was the only scientist taking marsh rabbits. North of the Keys, 10 years earlier, Nicholas Holler and Clinton Conaway were studying the reproduction of this now-endangered species.

“From September 1968 through August 1969, 610 marsh rabbits were collected by hand or with a .22 caliber rifle in sugarcane plantations south and west of Belle Glade, Palm Beach and Hendry counties, Florida, at the southern edge of Lake Okeechobee. Rabbits were readily obtained except in July, August, and September…. After collection, rabbits were weighed and one eye and one front paw were preserved in 10 percent formalin.” [14]

To put this into perspective, the MSRP (published 30 years after Holler and Conway’s research) suggests that there may be only 100–300 marsh rabbits left. [5]

How’s that for irony? It seems the best evidence of a declining population comes from two scientists who killed several hundred marsh rabbits 40 years ago.

Key Largo Woodrat
ABC’s reference to Key Largo woodrat mortality is actually an accurate recounting of what’s in the USFWS plan:

“In addition, cats accounted for 77 percent of the mortality during a recent re-introduction of the Key Largo woodrat (S. Klett, Refuge Manager, personal communication).” [1]

Such personal communications—even by knowledgeable, honest professionals—are no substitute for rigorous, science-based reporting. What kind of sample size are we talking about? Over what duration? Under what conditions? Where? Etc.

More to the point, though: here is ABC once again blatantly misrepresenting the science (or the closest thing we’ve got to science, in this case). USFWS is talking about a portion of the population, while ABC is talking about the entire population. And I have to think the people responsible are smart enough to know the difference—which, of course, can mean only one thing: it’s not the intelligence that’s lacking here, but the integrity.

The Rest of the Best
But what about all the rest of the science—the “best available,” according to Holmer, don’t forget—that USFWS including in its Integrated Predator Management Plan/Draft Environmental Assessment? Among the more egregious errors and misinterpretations I cited in my comments to USFWS:

  • Another of the papers cited by USFWS 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.” [17]
  • 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, [18] while Churcher and Lawton surveyed residents of a small English village. [19]
  • Among the evidence 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] is Rich Stallcup’s 1991 article from the Observer, a publication of the Point Reyes Bird Observatory. In fact, “A Reversible Catastrophe” is little more than Stallcup’s advice—at once both folksy and sinister—about defending one’s garden from neighborhood cats (“…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.” [21]).
  • Another of the studies cited by FWS—a 2008 paper by Sax and Gaines—isn’t about cats at all. Or even invasive animals. It’s about invasive plants. [22]
  • Citing the Centers for Disease Control and Prevention’s website, USFWS 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.”

    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.”

    (Unwilling to do their own research and writing, ABC uses exactly the same language and cites the same CDC website as USFWS. Had they simply clicked on the link, they might have avoided the blunder—which, I think, speaks volumes about little scrutiny they gave the USFWS plan before backing it.)

This is what Holmer is referring to when he says USFWS “deserves credit for bringing the best available science to bear on the management of exotic predators inhabiting National Wildlife Refuge lands regardless of the emotional aspects of the issue.”

What’s Missing
In addition to everything USFWS gets wrong, though, there’s also everything they overlooked or ignored (again, each point is covered in detail in my comments to USFWS). For example:

Mesopredator Release
“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.” [23] Several studies have demonstrated such an “explosion” of non-native rat populations as a result of cat populations being eliminated. [24–27]

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.” [26] 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.” [25]

But USFWS doesn’t even mention the risk of mesopredator release, 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. And controlling these rats is complicated considerably by the need to protect Lower Keys marsh rabbits. Indeed, the MSRP warns of these rabbits coming into contact with pesticides and “poisons used to control black rats.” [5]

Based on evidence cited by USFWS itself, it’s clear that a dramatic reduction in the number of free-roaming cats in the Keys (assuming it’s possible—see below) will very likely have a negative impact on the marsh rabbit population—and may well lead to their extirpation from any Key where these rats are present.

Such impacts would also likely affect the Key Largo cotton mouse [28–29], Key Largo woodrat [30–31], and silver rice rat [32–33], all of which USFWS identifies as species of particular concern, and which are threatened—either through predation or competition—by non-native rats such as the black rat.

Removing Cats
Reports indicate that USFWS 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. [34] Their efforts four years later—at a cost of $50,000—were equally ineffective. [9–10]

None of which should surprise USFWS. “Successful” eradication efforts require both extraordinary resources and profound cruelty. For example:

  • 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.” [15]
  • 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.” [36] 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 USFWS admits, such methods are “not… socially acceptable” and “inconsistent with the points of consensus developed by the stakeholder group.” Yet, they offer nothing in the way of a feasible alternative; their latest plan is just more of what’s been done—and proven ineffective—in the past.

Because it’s extremely doubtful that USFWS will be able to remove the cats quickly enough to keep up with reproduction rates (again, consider the “success” stories outlined above), the most likely outcome of their plan 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.

•     •     •

I fully expected ABC to support the USFWS plan. And, come to think of it, I should have expected them to blindly embrace the underlying science. After all, this is the same organization that’s been trying, since at least 1997, to sell the Wisconsin Study as valid research.

And, more recently, ABC endorsed “Feral Cats and Their Management” (also known as the University of Nebraska report) as if it were valid research.

Perhaps this is what ABC President and CEO George Fenwick meant when he wrote, in the preface to The American Bird Conservancy Guide to Bird Conservation, “every point of view has its own science.” [37]

Literature Cited
1. 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

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

2. Forys, E.A., Metapopulations of marsh rabbits: A population viability analysis of the Lower Keys marsh rabbit (Sylvilagus palustris hefneri), in Department of Wildlife Ecology and Conservation. 1995, University of Florida: Gainesville. p. 244.

3. 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

4. Forys, E.A. and Humphrey, S.R., “Home Range and Movements of the Lower Keys Marsh Rabbit in a Highly Fragmented Habitat.” Journal of Mammalogy. 1996. 77(4): p. 1042-1048. http://www.jstor.org/stable/1382784

5. 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

6. Jones, E. and Coman, B.J., ” Ecology of the feral cat, Felis catus (L.), in southeastern Australia.” Australian Wildlife Research. 1981. 8: p. 537–547. http://www.publish.csiro.au/paper/WR9810537.htm

7. Liberg, O., “Food Habits and Prey Impact by Feral and House-Based Domestic Cats in a Rural Area in Southern Sweden.” Journal of Mammalogy. 1984. 65(3): p. 424-432. http://www.jstor.org/stable/1381089

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

9. 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

10. 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

11. Ferriter, A., et al., The Status of Nonindigenous Species in the South Florida Environment, in 2008 South Florida Environmental Report. 2008, South Florida Water Management District.

12.  Engeman, R., Constantin, B., and Hardin, S., “Species Pollution” in Florida: A Cross Section of Invasive Vertebrate Issues and Management Responses, in Invasive Species: Detection, Impact and Control, C.P. Wilcox and R.B. Turpin, Editors. 2009. p. 179–197.

13. Lazell, J.D., Jr., “A New Marsh Rabbit (Sylvilagus palustris) from Florida’s Lower Keys.”Journal of Mammalogy. 1984. 65(1): p. 26–33. http://www.jstor.org/stable/1381196

14. Holler, N.R. and Clinton, H.C., “Reproduction of the Marsh Rabbit (Sylvilagus palustris) in South Florida.” Journal of Mammalogy. 1979. 60(4): p. 769–777. http://www.jstor.org/stable/1380192

15. Cruz, J.B. and Cruz, F., “Conservation of the dark-rumped petrel Pterodroma phaeopygia in the Galápagos Islands, Ecuador.” Biological Conservation. 1987. 42(4): p. 303-311. http://www.sciencedirect.com/science/article/B6V5X-48XKMBP-17J/2/f81b57e317f217802d9aca8b6927a88c

16. Kirkpatrick, R.D. and Rauzon, M.J., “Foods of Feral Cats Felis catus on Jarvis and Howland Islands, Central Pacific Ocean.” Biotropica. 1986. 18(1): p. 72-75. http://www.jstor.org/stable/2388365

17. Calver, M., et al., “Reducing the rate of predation on wildlife by pet cats: The efficacy and practicability of collar-mounted pounce protectors.” Biological Conservation. 2007. 137(3): p. 341-348. http://www.sciencedirect.com/science/article/B6V5X-4NGBB7H-3/2/456180347a2c3916d1ae99e220dd329e

18. Coleman, J.S. and Temple, S.A., “Rural Residents’ Free-Ranging Domestic Cats: A Survey.”Wildlife Society Bulletin. 1993. 21(4): p. 381–390. http://www.jstor.org/pss/3783408

19. Churcher, P.B. and Lawton, J.H., “Predation by domestic cats in an English village.” Journal of Zoology. 1987. 212(3): p. 439-455. http://dx.doi.org/10.1111/j.1469-7998.1987.tb02915.x

20. 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.

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

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

22. Sax, D.F. and Gaines, S.D., Species invasions and extinction: The future of native biodiversity on islands, in In the Light of Evolution II: Biodiversity and Extinction,. 2008: Irvine, CA. p. 11490–11497. www.pnas.org/content/105/suppl.1/11490.full

http://www.pnas.org/content/105/suppl.1/11490.full.pdf

23. Soulé, M.E., et al., “Reconstructed Dynamics of Rapid Extinctions of Chaparral-Requiring Birds in Urban Habitat Islands.” Conservation Biology. 1988. 2(1): p. 75–92. http://www.jstor.org/pss/2386274

http://deepblue.lib.umich.edu/bitstream/2027.42/74761/1/j.1523-1739.1988.tb00337.x.pdf

24. 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

25. 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/

26. 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

27. 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

28. 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

29. 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

30. 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://ecos.fws.gov/docs/five_year_review/doc1985.pdf

31. 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

32. 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

33. 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

34. 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.

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

Keys: To the Future

3 Feb 2011

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

1. 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

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

2. Cruz, J.B. and Cruz, F., “Conservation of the dark-rumped petrel Pterodroma phaeopygia in the Galápagos Islands, Ecuador.” Biological Conservation. 1987. 42(4): p. 303-311. http://www.sciencedirect.com/science/article/B6V5X-48XKMBP-17J/2/f81b57e317f217802d9aca8b6927a88c

3. Kirkpatrick, R.D. and Rauzon, M.J., “Foods of Feral Cats Felis catus on Jarvis and Howland Islands, Central Pacific Ocean.” Biotropica. 1986. 18(1): p. 72-75. http://www.jstor.org/stable/2388365

4. Calver, M., et al., “Reducing the rate of predation on wildlife by pet cats: The efficacy and practicability of collar-mounted pounce protectors.” Biological Conservation. 2007. 137(3): p. 341-348. http://www.sciencedirect.com/science/article/B6V5X-4NGBB7H-3/2/456180347a2c3916d1ae99e220dd329e

5. Coleman, J.S. and Temple, S.A., “Rural Residents’ Free-Ranging Domestic Cats: A Survey.”Wildlife Society Bulletin. 1993. 21(4): p. 381–390. http://www.jstor.org/pss/3783408

6. Churcher, P.B. and Lawton, J.H., “Predation by domestic cats in an English village.” Journal of Zoology. 1987. 212(3): p. 439-455. http://dx.doi.org/10.1111/j.1469-7998.1987.tb02915.x

7. n.a., State of the Birds, United States of America, 2009. 2009, U.S. Department of Interior: Washington, DC. p. 36. http://www.stateofthebirds.org/

www.stateofthebirds.org/pdf_files/State_of_the_Birds_2009.pdf

8. 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

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://www.ncbi.nlm.nih.gov/pubmed/15552312

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

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

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

11. Sax, D.F. and Gaines, S.D., Species invasions and extinction: The future of native biodiversity on islands, in In the Light of Evolution II: Biodiversity and Extinction,. 2008: Irvine, CA. p. 11490–11497. www.pnas.org/content/105/suppl.1/11490.full

http://www.pnas.org/content/105/suppl.1/11490.full.pdf

12. Elliott, J. (1994, March 3–16). The Accused. The Sonoma County Independent, pp. 1, 10.

13. 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

14. 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

15. 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

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

17. 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/

18. Soulé, M.E., et al., “Reconstructed Dynamics of Rapid Extinctions of Chaparral-Requiring Birds in Urban Habitat Islands.” Conservation Biology. 1988. 2(1): p. 75–92. http://www.jstor.org/pss/2386274

http://deepblue.lib.umich.edu/bitstream/2027.42/74761/1/j.1523-1739.1988.tb00337.x.pdf

19. Crooks, K.R. and Soulé, M.E., “Mesopredator release and avifaunal extinctions in a fragmented system.” Nature. 1999. 400(6744): p. 563–566. http://www.nature.com/nature/journal/v400/n6744/abs/400563a0.html

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

Operation Sisyphus

13 Jan 2011

The draft environmental assessment (EA) for the Florida Keys National Wildlife Refuges Complex Integrated Predator Management Plan (download PDF), released last week by the U.S. Fish and Wildlife Service (FWS), aims to eliminate free-roaming cats in the Keys. Not that this is anything new—FWS (along with USDA, and some state agencies) has been trying to do this for years now.

Plans include the trapping/removal of free-roaming cats—owned and unowned alike—from refuge lands and other public lands nearby, as well as from other land (including private property) where cats may be considered a threat to vulnerable native species. TNR has been dismissed as an option, and FWS proposes to prohibit the feeding of feral cats wherever possible.

Unfortunately, the proposed plan is unlikely to be any more successful than previous efforts. There’s plenty to dislike about the FWS plan—including the risk that it may set a dangerous precedent nationwide. The deadline for public comments (see Plan for details) is February 3.

Justification or Rationalization?
In a section of the document called Justification for Management Action, FWS lays out their numerous grievances against “non-native species and human-subsidized populations of native predators.” [1] As a review of the relevant literature, the sub-section on domestic cats leaves much to be desired is a train wreck.

In fact, if this were a college-level term paper, it would likely receive a failing grade—followed, perhaps, by disciplinary action. (And, if it were allowed under the law, maybe a drug test, too.)

Science
Among the references cited here (about three-quarters of which I’m familiar; the rest I’m still chasing down) is, admittedly, some rather damning evidence. For example:

  • The near-extirpation of rock iguanas from Pine Cay in the Caicos Islands during the 1970s. “The decline, from an estimated adult lizard population of nearly 5,500, was due primarily to predation by domestic dogs and cats introduced to the island simultaneously with hotel construction.” [2] (Strangely, FWS cites Iverson’s paper not as an example of a near-miss, but of a global extinction. This, however, pales in comparison to the “strangeness” of many of their other citations.)
  • On Little Barrier Island, off the coast of New Zealand, cats “were considered to have been the sole cause of the local eradication of North Island saddleback and to have contributed to the extinction of the Little Barrier snipe, and to threaten, by their continued presence, grey-faced, black, and Cook’s petrels. Cats probably also contributed to the decline of tuatara and the 12 lizard species known to be present on Little Barrier Island.” [3]

Sci-Fi
On the other hand, much of the FWS’s evidence is, at best, circumstantial. Among the studies cited to support their claim that “free-roaming cats have been shown to be a major cause of 33 native species extinction [sic] globally,” 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.” [4]

And, as with the rock iguanas, 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. 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.

Another of the papers cited by FWS has nothing to do with extinctions at all. As the authors themselves 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.” [5]

FWS argues that “many of the species impacted by free-roaming cats are federally listed threatened or endangered species and federally protected migratory birds.” While probably true, this statement is also largely meaningless. According to the 2009 State of the Birds report, published by the Department of the Interior (which oversees FWS):

“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.” [6]

That translates to approximately 31 percent of all birds in this country being species of concern. FWS makes it sounds as if perhaps the cats are targeting these birds; in fact, they could just as easily have claimed that many of the species impacted by all forms of mortality are federally listed threatened or endangered species and federally protected migratory birds of these birds.

Hang in there, though—it gets better. I mean worse.

Fantasy
Also listed among the evidence of island extinctions were Coleman and Temple’s 1993 survey of rural Wisconsin residents about their outdoor cats [7], and Churcher and Lawton’s “English Village” study [8]. (While England is an island, it’s quite a stretch to suggest that Felmersham’s House sparrows are at risk of extinction.)

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 [9] and Jessup. [10]

As I’ve discussed previously, Hawkins’ dissertation work was 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,” [9] for example. A closer look reveals that five of the nine ground-feeding birds showed no preference for either area of the study site. One could, based on Hawkins’ findings, just as easily conclude that more than half of the ground-feeding species studied were indifferent to the presence of cats.

Jessup cites some well-known predation studies, but his concern is the condemnation of “trap, neuter, and reabandon,” [10] as he calls it (“Abandonment of animals cannot be morally justified and is illegal under state humane laws… If it is illegal to abandon a cat once, how can it be legal to do it a second time? How can veterinarians justify being party to abandonment, an illegal act of animal cruelty?” [10])

FWS suggests 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 their 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 Stallcup gets most of that wrong. Mostly, 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.” [11]

Discourage them? Among Stallcup’s suggestions: “…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.” [11]

No feral cat witch hunt would be complete without some public health threat fear-mongering, and FWS’s plan is no different:

“According to the Centers for Disease Control (CDC), 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]

But 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.”

And finally, there’s the paper by Sax and Gaines. If the previous examples miss their mark, this one’s a full-blown non-sequitur. Though the authors do mention “the extinction of many native animal species on islands” [12] 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.” [12, emphasis mine]

•     •     •

FWS intends to eliminate free-roaming cats from the Florida Keys, and this is the best they can do? If so, well, perhaps they ought to be doing something else. If this is their “justification for action,” then any subsequent action can, I think, rightfully be considered unjustified.

Predator Management
Among the animals to be monitored throughout and/or removed from the four refuges that make up the Florida Keys National Wildlife Refuges Complex (National Key Deer Refuge, Key West National Wildlife Refuge, Great White Heron National Wildlife Refuge, and Crocodile Lake National Wildlife Refuge) are non-native reptiles and rodents, native raccoons, and, of course, the cats.

“Presence of exotic non-native iguanas, lizards, and large-bodied snakes will be detected through reports, incidental sightings, and the community-based interagency ‘Python Patrol’ network. Exotic reptiles will be immediately dispatched in accordance with AVMA guidelines for humane euthanasia.” [1]

“Any non-native opossum, armadillo, or rat caught incidentally in the live traps targeted for cats on Refuge lands will be immediately dispatched in accordance with the American Veterinary Medical Association (AVMA) guidelines for humane euthanasia. All native species will be immediately set free.” [1, emphasis mine]

“Raccoons trapped incidentally in live traps targeted for cats or other non-native predators will be released alive at the trap location… Raccoons that exhibit severe disease or other serious health issues will receive appropriate evaluation, which may include care by a state-certified wildlife rehabilitator or euthanasia as recommended by a qualified veterinarian or animal control services provider… If field studies and monitoring indicate that raccoon populations are having a negative impact on endangered species, the USFWS will reevaluate the need to implement more direct control by removal of raccoons from sensitive habitats. Removal could include, but not be limited to, transfer to a wildlife park or zoo, a state-certified wildlife rehabilitator, or euthanasia. Any decision by the Service to use lethal control measures on raccoons will trigger additional public notification and an amendment to this EA.” [1]

Free-roaming Cats
But, as I say, the cats are the real focus here: “The USFWS will remove all free-roaming cats found on Refuge lands through live trapping,” at which point, the cats will become of the responsibility of any one of three (currently, two; a third contractor is currently being sought) Monroe County animal control providers.

“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]

Of course, it’s no secret what happens to the vast majority of feral cats 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.”

I asked Connie Christian, Executive Director of the Florida Keys SPCA, about this last week. “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. (Interestingly, FKSPCA is involved with TNR, which FWS wants to eliminate—more on that in a moment.)

What about that “relocation to long-term facilities on the mainland” option? There was some discussion of this option during stakeholder meetings that took place in 2008. And local papers carried stories suggesting the possibility. [13, 14] Now it looks like FWS is dumping this is the laps of Monroe County animal control providers.

I guess they can say they tried.

Expanding Territory
But FWS isn’t stopping at their property line—and the four refuges included in the plan already make up, according to my calculations, more than 28 percent of the Keys’ total land mass. According to the South Florida Multi-Species Recovery Plan (MSRP), FWS has plans to use land acquisition and conservation easements or agreements to protect the endangered Lower Keys marsh rabbit. [15]

The MSRP, excerpts of which are included in the EA, also spells out FWS’s intention to “remove nuisance feral cats” from land “near rabbit habitat” in the Lower Keys. [1] Additional plans include deed restrictions “to prohibit free-roaming cats” [1] in areas where they might be a threat to the rabbits, the Key Largo Woodrat, or the Key Largo Cotton Mouse. And to “enforce deed restrictions of cat control in Ocean Reef Club and other areas.” [1]

The Ocean Reef Club, of course, is home to ORCAT, perhaps the best known—and certainly one of the most successful—TNR programs in the country. According to their website, ORCAT has reduced the island’s population of cats from approximately 2,000 cats, in the early 1990s, to about 350 today, “about 100 of which reside at the Grayvik Animal Care Center.”

Frankly, I’m not sure what FWS means by “enforce deed restrictions” (one of many follow-up items on my to-do list). Other aspects of their plan, however, are straightforward:

“Feral cat colonies and feeding stations on Refuge lands will be identified and removed. The USFWS will also coordinate with county and state agencies to assist in the identification and removal, where feasible and legal, cat colonies and feeding stations on other public properties that are adjacent to or near Refuge lands. Extensive public outreach will be conducted to encourage people who feed free-roaming cats to cease doing so, and to promote trapping and relocating those animals to long-term facilities on the mainland where they will no longer be a threat to Refuge’s wildlife.” [1]

Something else that’s clear: FWS is going after pet cats, too. The MSRP includes plans to “establish a program to license domestic cats, implement leash laws, eliminate cat-feeding stations, implement spay and neuter program, increase awareness through educational material, test diseases, and remove nuisance feral cats.” [15]

Is this mandatory spay/neuter (which has been shown to fail when implemented in the absence of adequate low- and no-cost services)? Does the FWS plan to test pets for, say FIV and FeLV? Lots of unanswered questions here, obviously.

Trap-Neuter-Return
It’s no surprise, then, given their plan for the removal of feeding stations—and cats—that FWS is staunchly opposed to TNR, which, they argue “does little to reduce cat predation on native wildlife.” [1]

Success Stories
“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.” [16]

Castillo and Clarke, though highly critical of TNR 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” [17] prior to beginning their research), Castillo and Clarke “saw cats kill a juvenile common yellowthroat and a blue jay.” [17]

“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.” [17]

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” [18].

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.” [1]

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.” [19] 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.” [19]

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 Los Angeles).

PETA
Finally—perhaps in a desperate attempt to appear as though their plan has the support of animal welfare organizations—FWS gives PETA a plug.

“Some animal advocates therefore often agree that traditional TNR programs are not the most appropriate choice, especially where cats are released near designated wildlife areas and at-risk wildlife populations (see the People for the Ethical Treatment of Animals’ Animal Rights Uncompromised fact sheets at www.peta.org/about/why-peta/default.aspx). For these reasons, TNR was considered but dismissed from further evaluation.” [1]

PETA, of course, is also opposed to caged birds, crating dogs, and zoos. When PETA is the only “animal advocate” you can get to endorse your approach, it’s time to rethink it.

Operation Sisyphus
The purpose of FWS’s Plan/EA “is to 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]

Will the plan work? Only time will tell, of course—but there’s plenty of reason for skepticism. If their “literature review” is any indication, FWS either doesn’t have a particularly strong grasp of the issues involved—or they’re not interested in sharing that understanding with the public.

Nitpicking? I don’t think so. In their attempt to focus—however carelessly—on the impacts of cats, FWS overlooks some key factors.

Mesopredator Release
FWS refers to two often-cited papers [20, 21] 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.” [20]

In Soulé’s example, 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 rats becoming the mesopredators.

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.” [23]

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.” [24]

Could something like this happen in the Florida Keys?

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 MSRP warns of these rabbits coming into contact with pesticides and “poisons used to control black rats.” [15]

“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.” [15]

Removing Cats
It’s also not clear that FWS will be able to remove the free-roaming cats from the Keys. For one thing, they have no idea how many are there. Only now—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]

Plus, FWS has a rather poor track record when it comes to actually trapping cats.

In 2007, they “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.” [25] Reports (from what I can tell, nothing official has been issued) suggest that fewer than 20 cats were caught—some of which were returned to their owners (kudos to FWS and USDA)—along with 81 raccoons, 53 of which were released alive. [26]

I think it’s safe to say that the Keys’ wildlife reaped little or no benefit from this effort. Had that same money been used for TNR, on the other hand…

So what’s different this time around?

Déjà Vu
All the while I’ve been doing the research for this post, I’ve been haunted by two quotes I’ve used rather extensively in the past. Actually, the first is not a quote as such, but the title of Merritt Clifton’s excellent article: Where cats belong—and where they don’t. [27]

The second comes from Gary Patronek, who argues that “the release of cats into an environment where they would impact endangered or threatened species, or even into wildlife preserves or refuges, is inexcusable.” [28] Patronek, the former Director of the Center for Animals and Public Policy at the Cummings School, and one of the founders of the Hoarding of Animals Research Consortium, continues:

“I do not believe that this is being advocated by cat protectors who see urban, managed colonies as an imperfect but still preferable alternative to the euthanasia of healthy animals. Abandoned pet cats whose own habitat has been reduced to colonies, and the wild species endangered by clear-cutting or beachfront development, are casualties of the same callous disregard for the lives of animals. I see little justification for shifting the role of cats to that of scapegoat.” [28, emphasis mine]

Well, isn’t this precisely what I’m advocating? I honestly don’t know.

Here’s what I do know:

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. And, in such habitats, it’s been shown that free-roaming cats can have a significant negative impact.

I also know that where cats have been eradicated, the process is a horror. In fact, it’s spelled out in some of the papers cited by FWS (though, understandably, they don’t draw attention to that):

  • 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.” [29]
  • 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.” [4]
  • 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.” [3] 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.” [3] (By way of comparison, the Keys are approximately 137 square miles in total area.)

I know that ecosystems—especially those as fragile as the Keys—are incomprehensibly complex, and that tinkering with them is incredibly risky. And there’s plenty we simply do not know, and cannot—despite our best efforts—predict.

But I know, too, that time is short. And that we’ll never have all the answers we’d like to have before the need for action precludes further inquiry.

Implementation
Put another way: I’ve given this issue a lot of thought—and, here’s what I’m afraid will happen in the Keys:

FWS will proceed with their plan, rounding up cats—ferals and pets alike—on and “near” public lands. The pet cats will mostly be returned, but some mistakes—the risk of which will likely increase in an atmosphere of mass trapping—will surely be made. Feral cats will be killed.

Progress will move slowly, as these things often do—far too slowly to keep up with reproduction rates. If feeding and TNR are eliminated (to whatever extent possible) throughout the Keys, the cats will simply “go underground.” No more monitoring—and sterilizing—by the “foot soldiers” who currently care for colonies of cats.

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

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. [30] By contrast, the authors suggest that 75 percent of cats would need to be sterilized to achieve the same result.

This model has its flaws, as I’ve explained elsewhere, but the study is one many researchers are familiar with. And, frankly, it’s convenient for my purposes here.

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 once they chase away the colony caretakers, it won’t be long before that’s the norm) cats continuously in order to achieve a 10 percent reduction in overall numbers.

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

FWS has—it seems—taken off the table the unspeakable methods so often employed on small, uninhabited islands.

“While lethal control is allowed by Refuge System policy, it is not a socially acceptable approach and is inconsistent with the points of consensus developed by the stakeholder group. This alternative would likely not be logistically feasible on a FKNWRC-wide basis and would not allow for adaptive management under a strategic habitat conservation approach.” [1]

But they’ve also taken TNR off the table. So, what’s left? We’re back to doing what we’ve been doing for years now—which, of course, is how we got into this mess in the first place.

From what I can tell, the FWS plan is nothing more than a warmed-over version of old-school trap-and-remove, an approach Mark Kumpf, president of the National Animal Control Association President from 2007 to 2008, describes as “bailing the ocean with a thimble.” [31] (There’s a metaphor that ought to resonate with people in the Keys!)

If so, 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—not much of a 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?

Literature Cited
1. 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.

2. Iverson, J.B., “The impact of feral cats and dogs on populations of the West Indian rock iguana, Cyclura carinata.” Biological Conservation. 1978. 14(1): p. 63–73. http://www.sciencedirect.com/science/article/B6V5X-48XKN72-1NN/2/bff9bfdeecb8ff6cec68527221b99a97

3. 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/

4. Cruz, J.B. and Cruz, F., “Conservation of the dark-rumped petrel Pterodroma phaeopygia in the Galápagos Islands, Ecuador.” Biological Conservation. 1987. 42(4): p. 303–311. http://www.sciencedirect.com/science/article/B6V5X-48XKMBP-17J/2/f81b57e317f217802d9aca8b6927a88c

5. Calver, M., et al., “Reducing the rate of predation on wildlife by pet cats: The efficacy and practicability of collar-mounted pounce protectors.” Biological Conservation. 2007. 137(3): p. 341-348. http://www.sciencedirect.com/science/article/B6V5X-4NGBB7H-3/2/456180347a2c3916d1ae99e220dd329e

6. n.a., State of the Birds, United States of America, 2009. 2009, U.S. Department of Interior: Washington, DC. p. 36.

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

8. Churcher, P.B. and Lawton, J.H., “Predation by domestic cats in an English village.” Journal of Zoology. 1987. 212(3): p. 439-455. http://dx.doi.org/10.1111/j.1469-7998.1987.tb02915.x

9. 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.

10. 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.avma.org/avmacollections/feral_cats/javma_225_9_1377.pdf

11. Stallcup, R., “A reversible catastrophe.” Observer 91. 1991(Spring/Summer): p. 8–9.

12. Sax, D.F. and Gaines, S.D., Species invasions and extinction: The future of native biodiversity on islands, in In the Light of Evolution II: Biodiversity and Extinction,. 2008: Irvine, CA. p. 11490–11497. www.pnas.org/content/105/suppl.1/11490.full

13. n.a. (2007, March 29). Key Deer Refuge wants to control feral cats: A plan to round up feral cats in the National Key Deer Refuge on Big Pine and No Name keys has animal-rights groups and area cat owners upset. The Reporter.

14. Busweiler, R. (2008, December 1). Feds begin drafting rabbit protection plan—BIG PINE KEY. The Key West Citizen.

15.  n.a., Multi-Species Recovery Plan for South Florida: Lower Keys Rabbit. 1999, U.S. Fish and Wildlife Service: Atlanta, GA. p. 151–171. www.fws.gov/verobeach/images/pdflibrary/lkmr.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. www.kiccc.org.au/pics/FeralCatsRome2006.pdf

17. 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.

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

19. Hatley, P.J., Feral Cat Colonies in Florida: The Fur and the Feathers Are Flying. 2003, University of Florida Conservation Clinic: Gainsville, FL. www.law.ufl.edu/conservation/pdf/feralcat.pdf

20. Soulé, M.E., et al., “Reconstructed Dynamics of Rapid Extinctions of Chaparral-Requiring Birds in Urban Habitat Islands.” Conservation Biology. 1988. 2(1): p. 75-92. http://deepblue.lib.umich.edu/bitstream/2027.42/74761/1/j.1523-1739.1988.tb00337.x.pdf

21. Crooks, K.R. and Soulé, M.E., “Mesopredator release and avifaunal extinctions in a fragmented system.” Nature. 1999. 400(6744): p. 563–566. http://www.nature.com/nature/journal/v400/n6744/abs/400563a0.html

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

23. Fan, M., Kuang, Y., and Feng, Z., “Cats protecting birds revisited.” Bulletin of Mathematical Biology. 2005. 67(5): p. 1081-1106. http://dx.doi.org/10.1016/j.bulm.2004.12.002

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

25. O’Hara, T. (2007, April 3). Fish & Wildlife Service to begin removing cats from Keys refuges. The Key West Citizen.

26. n.a., Lower Florida Keys National Wildlife Refuges Comprehensive Conservation Plan. 2009, U.S. Department of the Interior, Fish and Wildlife Service: Atlanta, GA.

27. Clifton, M. Where cats belong—and where they don’t. Animal People 2003.  http://www.animalpeoplenews.org/03/6/wherecatsBelong6.03.html.

28. Patronek, G.J., “Letter to Editor.” Journal of the American Veterinary Medical Association. 1996. 209(10): p. 1686–1687.

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

30. 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/javma_225_12_1871.pdf

31. 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/broader_view_of_cats.pdf