Miami Beach officials, disturbed by reports of a hookworm outbreak, have taken a rather unique approach to the problem: they’ve created a cat and cat poop map.

This fall, several cases of cutaneous larval migrans were reported – and highly publicized – in the Miami Beach area, something that is of particular concern for a tourist city that doesn’t want people thinking the city’s beaches are biohazardous.

Cutaneous larval migrans is a skin condition caused by migration of hookworm larvae through the skin. Dogs and cats can be carries of hookworms and pass eggs in their feces. Larvae then hatch from these eggs and can penetrate the skin (of people and animals alike) after being in the environment for a few (usually 2-9) days. If someone has contact with infectious larvae, such as by stepping on them while bare foot on a beach, the larvae get into their skin and start migrating, causing this very itchy skin condition.

Feral (stray) cats are the main problem in Miami Beach. Stray cats and beaches are a bad combination, since stray cats tend to have high rates of hookworm carriage, they often defecate in sand on the beach, and of course people often have direct contact between bare skin and beach sand. Identifying where stray cats live (and poop) is important for disease control and public education. “We needed to identify where the cats are eating — and where they’re pooping — to address this problem” stated a program organizer. To do this, city sanitation workers were given GPS devices and instructions to go find cats. Data were uploaded into a mapping system, and areas where cats tend to congregate were identified. Not surprisingly, certain areas of sane dunes are being used as industrial-sized litterboxes by the cats.

This type of information can be used in several ways. It can be useful for evaluating cat populations: where they are, where they go, and what happens to them over time. It can help identify areas where the cat population needs to be addressed through measures such as trap, neuter and release programs (as are being used in Miami Beach). It can also help with development of targeted education programs, by putting up warnings in heavily cat- and cat poop-infested areas. City health officials think that the combination of tracking, the increased spay/neuter program and targeted warnings to sunbathers have helped staunch the outbreak.

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  • Cat

    Except that TNR addresses nothing except avoiding euthanasia. The method does not reduce the number of feral cats. There is collateral damage to the environment (and to public health). There is no scientific literature that supports that the method will reduce the risk of disease transmission to people or to native wildlife. The method infringese on property rights, and some feel that TNR is an inhumane option for domestic animals – which is what feral cats are – they are not wildlife. The cats need to be removed.

    And tonight in Canada:

  • Scott Weese

    There’s no doubt that TNR is controversial, but what does “The cats need to be removed” mean and how does it help? These are feral animals and most would not be potential pets. They’d be euthanized if rounded up for a shelter and would take up space for more adoptable animals. Otherwise, you’re talking about a mass cull. Culling of cats has never been shown to be effective because you can’t kill them all. Their reproduction rate means that other cats rapidly fill the ecological niche left open by the cull. In a short period of time, you’re at the same spot. TNR isn’t perfect but at least you are helping reduce propagation of that cat population. The answers aren’t nearly as clear as the misleading information on your website (i.e. take a look at the full sentence from the AVMA, not just the partial sentence you cite. You present a misleading opinion of the AVMA’s statement, which eliminates any credibility. PETAs position that you state is also not what they really say. Yes, they have concerns about how some TNR programs are run, but they have guidelines for management of feral cat colonies that includes TNR).

  • The problem of feral cat management is admitterly complicated, but TNR management is simply NOT working to control cat populations, which are a growing environmental and human health problem. The estimated 120 million(and growing)feral and free-ranging housecats in the U.S. are killing up to an estimated one billion migratory and resident birds and other small animals (including endangered species in the United States each year (note that the massive Gulf oil spill killed only 10,000 birds in comparison). They spread diseases and parasites, such as rabies, toxoplamosis and hookworm, to wildlife and humans.

    Miami’s answer to this is to spay and re-release the cats back into nature and to map cat poop on the beach. That’s pathetic. Our nation’s citizens and native wildlife deserve more protection than this. In addition, such practices are cruel to the feral cats themselves. In the absence of human care, cats are much more likely to live miserable shortened lives, killed by collisons with cars, predation by coyotes (a recent study showed that 40% of the diet of coyotes in Tuscon, AZ were cats), and disease. Even PETA, among the most radical of all animal rights groups, is now calling for live capture and euthanasia as the answer to feral cat over-population, not ineffective TNR. The Wildlife Society, an oranization representing over 10,000 wildlife professionals, as well as many other conservation and scientific organizations have also come out against TNR. That should tell you something!

  • Cat

    To answer your first question – removed means exactly that. Trap them and take them out of the environment. Do not put them back (which many feel is simply re-abandonment). The results? Yes, most may be euthanized in impoundment facilities/shelters, although many of the cats in these colonies are not so feral. These cats can be socialized and adopted as pets. There are few sanctuaries dedicated to feral cats, but people caring for outside cats may be able to fence them in or enclose them on private property.

    And how would the feral cats take up space in a shelter if they were going to be euthanized?

    Given the number of feral cats roaming the US, you are right – we cannot trap and remove them all, but we certainly cannot TNR them all either. That IS an important point of the AVMA position statement. There is no significant reduction through TNR – nothing misleading about that. The full statement is available on the Positions page:

    People will TNR to avoid euthanasia despite the impact on public health and the environment hence there are guidelines. But, PETA does not support TNR – they feel euthanasia is the more compassionate option.

    And here:

    “We believe that it can be marginally acceptable to trap, vaccinate, alter, and release feral cats when the cats are isolated from roads, people, and animals who could harm them, are regularly attended to by people who not only feed them but also provide them with veterinary care, and are kept in areas where they do not have access to wildlife and the weather is temperate. The biggest problem is that most cats, once they are caught to be sterilized, will not be able to be lured by traps again when they are sick or injured.”

    Marginally acceptable. And the cats cannot have access to wildlife. How many colony caregivers do you know who abide by that? Or the rest of those guidelines?

    PETA is not in favor of the concept of ‘no kill’ either.

    As for cats filling the niche – not so, if nothing is there to support them. The food source needs to be removed. TNR advocates refer to what you mentioned as “the vacuum effect”.

    You also ask how removal helps. Stopover sites are vital for many species of migratory birds. Removal provides respite, as even the mere presence of cats can affect reproduction and breeding success. Even if at some point in the future – weeks, months, or a year or more away, a new cat shows up – the time in between is beneficial, if not critical, for breeding and resident wildlife. In TNR, there is no break. The colonies exist indefinitely – the cats are always there. Feeding does not lessen the motivation to hunt.

    You say that in TNR ‘at least you are helping reduce the propagation of that cat population’. There is no scientific support for that statement. What about the cats that have evaded capture and continue to breed?

    The root cause of cat overpopulation is irresponsible pet ownership. Aside from avoiding euthanasia, there is one more thing that TNR does – and that is – undermine any effort to promote responsible pet ownership. TNR not only enables abandonment – in essence, the method condones it.

  • Scott Weese

    I’m not actually an active proponent of TNR programs, but I feel that I should point out the issues that get raised.

    Saying TNR is not working to control cat populations is a rather weak statement since it is so rarely used.

    Yes, cats kill a lot of birds. But, there’s a difference between an oil spill and an ecological cycle. Raptors kill a lot of birds every year. We don’t want to cull them to save songbirds. (I know…not a great example but we need to think broadly).

    Yes, feral cats don’t live pampered lives and they may become prey. But, does that mean that a cat who lives in a feral colony and is ultimately killed by a predator lived a miserable life and was better off being killed earlier by human hands? I have a hard time convincing myself about that one.

    I’m also not convinced PETA is pushing for capture and euthanasia over properly done TNR. Neither is ideal.

    TNR isn’t the solution, but it still might be a useful tool in some situations if done well. It would be better to make sure people kept their cats indoors and had them neutered, but 100% compliance isn’t realistic so other measures need to be considered.

    How do we balance cat welfare and wildlife welfare? It’s hard to say. It gets complicated and confusing when groups with specific focuses get involved.

    None of our options are great. Just because something isn’t a good option doesn’t mean it’s a bad option that shouldn’t be done. If Miami does a good TNR program, with proper colony management and vaccination of cats, is this actually hurting? Maybe it’s increasing the number of birds killed by those cats, but is there a net negative effect on the overall bird population in the area? I don’t know. Is there a negative impact on humans? Maybe not. In fact, if this increases the percentage of rabies-vaccinated cats, it might help, compared to an unmanaged colony. I don’t pretend to have the answers but we need unbiased assessments.

  • dave jessup

    Dear Scott et al,

    If you are not a proponent of TNR you are certainly repeating their arguments and often misleading statements. As others have stated there is no good evidence that TNR actually reduces feral cat populations in the long run and over landscapes. Even Julie Levy has admitted that in some writings (see Foley, Foley and Levy), although often denies it in talks.

    Nor is there any evidence that once removed, feral cat populations will come back to an area IF THE FOOD IS REMOVED. It is a self perpetuating situation and becomes a spot for the worst oe owners to “dump and run”, it enables abandonment.

    When local numbers get high and just spaying can keep up with abandonment and kittens TNR groups regulalry remove cats from TNR colonies and move them to new locations and start new ones. This is not credible population control, it is assisted metasitsis.

    Feral cats may not be easy to make pets of, but many can be tamed and become wonderful pets. I have done this with 4 cats in the last 20 years myself and only 1 remained mean, and my family and I have tamed many feral kittens for adoption. If you really take the time to sit and observe feral cats you will really understand that TNR is not doing many of them a kindness. Being killed by cars, dogs, coyotes, folks with sticks and pellet guns who don’t like cats in their yard, yellow jacket stings, raccoon mauling, cat bite abcesses, violent cold streaks and other things that most commonly kill feral cats are neither painless nor humane.

    Which species most commonly is associated with human PEP for rabies…..cats….where do cats get exposed to rabid skunks, raccoon and fox….do you suppose outdoor feeding sites might be a good answer ?

    Sure you can deal with a cat flea associated typhus outbreak by bombing the area with insecticides, but if you don’t remove and surpress the cat numbers are you going to do that monthly until Hell freezes over ?

    Does the person whose child gets visceral or occular larval migrans after going swimming at the beach in Miami have a case when they sue the city for everything as well as pain and suffereing for failure to implement adequate measures to protect public health ?

    Hearing a colleague and credible public health veterinarian defend TNR instead of defending public health is very disturbing. It may stem in part from the regular lobbying that your professional organizations have allowed pro-TNR groups at your meetings over the last 4-5 years while consistiently refusing to listen to those with alternative points of view. Your speciality is being mislead…..

    dave jessup

  • Scott Weese

    Dave et al

    This is an interesting debate and I appreciate the reasonable nature of all the posts (no name calling and the like!).

    I do see both sides and as I said, I’m not an active supporter of TNR. I think these comments highlight the complexity of the problem and the fact that what is good for one thing may not be good for something else. It also highlights the need for objective data generated by proper research.

    I’m certainly not arguing for TNR at the detriment of public health (since I’m not arguing for it, for one thing, and since I’m not sure about the net public health benefit or risk).

    Does rabies vaccination of colonies reduce the risk of rabies exposure in the human population? Probably, if done well, it reduces cat-associated rabies risk. But doing it well is an issue.

    Are TNR cats a risk for ocular and visceral larva migrans? Maybe, but it’s got to be very low in most areas given the low incidence of disease. Cutaneous larva migrans is certainly a greater risk, but a much less serious disease.

    Do colonies help maintain vector-borne pathogens like Bartonella? Probably. Does that pose a risk to people if they have no contact with the animals? Does that pose a risk to indoor-outdoor cats? Are we better off focusing more efforts on keeping cats indoors?

    I don’t know, and I don’t think anyone really knows the answer. We can probably all agree that poorly done (or in an inappropriate location), TNR is not a good thing. Are there situations where it can be helpful, or at least not detrimental to human and pet populations? I don’t know.

    It is a very polarizing topic. There are certainly extreme positions at both ends, and lobbying based on questionable science. I think the only way for the middle majority to make objective decisions is for independent research to be performed on the impact of TNR versus colony eradication versus no intervention. that won’t answer all the questions because of the potential for variability between sites, but it would help.

    It would be easier if we had more responsible pet ownership so the feral population wouldn’t be replenished so easily, and indoor only cats to reduce the bridge between feral cats and housedholds, but that’s not easy either.

  • Scott, feral and free-ranging domestic cats are an exotic invasive species–unlike raptors, they do not belong in North American habiats and their numbers are artificially exaggerated through human care and feeding. You are comparing apples and oranges.

  • dave jessup

    Hi Scott,

    Yes, it is controversial. But there is a good deal of published science on this. Unfortunately TNR folks and some in the veterinary community choose to ignore that which doesn’t suit their view, or which is not published in a veterinary journal. If we expect to have our views taken seriously we should probably respect and seriously utilize all the published literature. In the 2004 paper I publihsed in the JAVMA special issue on feral cat welfare you will find over 50 citations supporting various points made, in Linda Winters paper about another 50.

    As Mike points out, cats are not native, when subsidized and concentrated they wipe out most native North American species that did not evolve with them. Unfortunately the species people claim they control, black rats and house mice, have had thousands of years to adapt to cats, and although they will certainly kill them, populations of both survive in significant numbers in the presence of cats. Not so for native wildlife. So much for “green rodent control”

    Sure, vaccination for rabies, IF it is provided, seems like a good idea. But when a feral cat bites or scratches someone there is no record of the date and type of vaccine used, little if any ability to indentify, catch and quarenteen the cat, so the human patient has to get a PEP or take the risk. So all the public health expense and risk is not mitigated by rabies vaccination. And many TNR programs do not vaccinate and/or do not followup to maintain vaccination. The largest TNR program in California, run by the CVMA, released 90,000 unvaccinated feral cats.

    So, as we have traveled down this road to TNR as public policy, what happened to concept of preventive medicine ?
    How and when did cat poop in public parks, on beaches and on the private property of unwilling citizens ever have neutral or no risk of negative public health consequences ?
    I don’t care if you are talking hookworm, roundworms, toxoplasmosis or ringworm, typhus or rabies, (obviously the later 3 not fecal asscoaited, but feral cat associated), there is an increased public health risk when feral cats can live and crap wherever they need to and people don’t know they are being exposed.

    As a public health expert I am sure you are well aware of the many worldwide local epidemics of soil or water source asscociated toxoplasmosis. Those can only be from oocysts shed in cat feces, usually by definition, feral cats. No other form of Toxo can live outside a hosts body and be infectious in soil or water. Yes, as TNR folks are quick to point out, a majority of cases worldwide are due to ingestion of the tissue cysts in undercooked meat. Latest molecular detective work says about 60%. That is cold comfort the the remaining 40% isn’t it ? If you do the numbers that is many, mnay tens of thousands. Again, what happened to preventive medicine ?

    With so many people today on immunosurpressive therapy, so many with HIV/AIDS, and many pregnant mothers, how can public health not be jeopardized by unexpected and unwanted cat poop on public property. And, unfortunately, in many cities and towns, public officials have been told that the public health risks of feral cats and TNR are negligable, often by well meaning, but TNR brainwashed public health officials.

    Finally….even when there are no controlled studies and absolute proof….Absence of evidence is not evidence of absence…What happen to preventive medicine ? I doubt Snow won any popularity contests when he took the handles off the water pumps in London….but he saved many lives, reduced suffering and founded modern preventive medicine…..


  • Here’s a brief list of organizations that have policies against TNR management of feral cats and that have also expressed the need for a much different and more effective approach to feral and free-ranging housecat management in this country and worldwide, one that emphasizes keeping cats indoors:

    Wildlife Disease Association
    American Bird Conservancy
    American Society of Mammalogists
    The Wildife Society
    Society for Conservation Biology
    National Aududon Society
    National Wildlife Federation
    American Association of Wildlife Veterinarians
    There are many others…

  • Cat

    Maybe these will convince you about PETA.

    The only way to balance cat and wildlife welfare is to keep them separate. As soon as we allow the cats access – a choice has been made and the choice is not in favor of native species whose true home is outdoors. A re-released cat may kill dozens if not hundreds or more animals in her lifetime – that is just not fair to wild animals already struggling to survive. Any solution cannot come at the expense of our natural resources or public health.

    The mantra by the TNR advocates is that by providing a single rabies vaccination a ‘barrier of protection’ is created. But where is the science to support this? In an open system that not only serves as a dumping ground, but also attracts rabies vector wildlife, often has friendly approachable cats, and harbors hard-to-trap cats that never get fixed or vaccinated (not to mention from your other blog post that vaccines may fail anyway), TNR can never work to improve public health. And a rabies shot certainly does no good for the myriad of other diseases transmittable to humans and/or wildlife. Did you know that feline panleukopenia virus can be transmitted to raccoons?

    Since when does being informed mean people/assessments are biased? The TNR Reality Check website is a resource that provides information of which many people are unaware.

    About one disease:

    Toxoplasmosis is the most common cause of intraocular inflammation in the world.

    More info here:

    BTW, you mentioned appreciating the reasonable nature of the posts. Gotta tell ya – you had nothing to worry about. By and large, the name-calling and other unacceptable behavior is a characteristic of the TNR crowd. Groups like Alley Cat Allies and too many individuals deem those simply opposed to the method as anti-cat and cat haters. Those descriptions are the less colorful ones – can’t post the others!

  • Peter Wolf

    I, too, appreciate the civil discourse here. And, as the topic already seems to have drifted from hookworms to TNR, I feel comfortable chiming in…

    Rather than dispute the various claims here (e.g., the number of the free-roaming cats, bird kills, rabies, Toxoplasma gondii, etc.), as I have done on my blog (—and which, would likely fall on deaf ears—I’d like to shift the focus further still if I may.

    In the interest of full disclosure (more for Steve than anybody else, as Michael Hutchins and David Jessup are very much aware of my position on the subject), I am a proponent of TNR.

    What I’d like to know is, what happens if TNR and the feeding of feral cats is outlawed? Then what?

    I’ve yet to hear from any TNR opponent spell it out. We all know the cats won’t disappear in the absence of TNR/feeding (though David Jessup suggests as much in his earlier comment). We can argue about rates of population growth, carrying capacity, etc.—but let’s keep it simple here. Under such a plan, there are these feral cats—an awful lot of them—that no longer have access to the assistance of humans (other than scavenging trash, say). OK, now what?

    Will it be like what was done on Marion Island, where—despite being only 115-square-miles in size, barren, and uninhabited—it took something like 16 years to eradicate 2,500 cats? Using disease (feline distemper), poisoning, intensive hunting and trapping, and—if I’m not mistaken—dogs. (I don’t imagine you’ll see this “success story” referred to by the organizations opposing TNR.)

    Or does Macquarie Island make for a better model? In 2000, cats were eradicated from this United Nations Educational, Scientific and Cultural Organization World Heritage Site in order to protect seabird populations. The resulting rebound in rabbit and rodent numbers, however, has been disastrous, prompting Federal and State governments in Australia to committed AU$24 million for an integrated rabbit, rat, and mouse eradication program.

    These are not rhetorical questions. As I say, I’ve heard plenty of arguments against TNR over the past year or so. I’ve yet to hear a single counter-proposal. Not one.

    Trap-and-remove? That’s not a proposal; it’s a sound bite. I really want to hear about how all this would play out.

    Peter J. Wolf

  • joe

    If stray cat feces is in the sand, Toxoplasmosis is in the water. Last one in is a rotten tape worm. Stray cats carry over thirty diseases they communicate to man. Most can be fatal. Anyone for a dip?