OK, this is the cat site. What are your thoughts on predation and TNR? - Page 2

Well, I've never adopted an animal from a shelter, and don't work with any shelters, so I wouldn't know. For whatever reason, we had our cats microchipped (if they ever got out, no one around here traps other than us, so I'm really not sure what our thinking was!) and we have to pay an annual fee - which we stopped paying for the very reason I just mentioned.

Amy already addressed this one.

I will add... I don't think anyone anywhere advocates that TNR in and of itself will solve the cat overpopulation problem. But then neither would trap-and-kill.

ALL TNR groups support low-cost s/n programs, educational programs, &etc. - and there are also those of us who work to relocate feral cats if they are on public land and potentially posing a problem to threatened/endangered species. TNR isn't appropriate everywhere, nor is it meant to work in a vacuum. The aim of trap-and-kill obviously is to increase mortality above naturally occurring limits, whereas in TNR we're just addressing fecundity. So either way - without stopping the inflow of "new" cats, you have to keep trapping or keep killing. Both require additional programs/laws/education.

I'm sorry, I don't mean to be a dunce here, but I'm still confused about the point you're trying to make that I'm just not getting. How do you trap the cats if you don't attract them? And if they're out there roaming - don't they need to be trapped to be sterilized? You put out food. The cats come. You trap them. You have them sterilized. If they're friendly, you try to find their owners - if you can't, you work on getting them adopted out - whether that's via a shelter or foster network - and the ferals or cats that have been so long on their own you think they're feral - get released. But how does not feeding them benefit anyone? If cats are in a neighborhood, and they're roaming, they need to be sterilized! If you're not feeding them... where do you put the traps? If you don't have food on a schedule... how do you know when to check the traps?

If you're not going to trap and sterilize - don't feed. Definitely. But if you're TNRing... You accidentally trap someone's cat. It's not microchipped and not wearing a collar. It goes home sterilized - with an ear tip.

Why?

If there's a community cat problem, and someone takes it upon themself to spend their own money trapping and sterilizing the animals that are out there because of other irresponsible members of the community, why should they legally be "burdened" with "ownership." All they're doing is providing a free service to the community in reducing the fecundity of animals that are already there and would be breeding if not for them.

But they're out there in numbers higher than "nature" can support anyway. Supplemental feeding by people simply creates an environment where they can be trapped and sterilized.

I STILL don't understand this point you're making between sterilized and intact cats. An ongoing TNR program attracts intact cats that are then sterilized.

Here's a real life example for you. I live in a farm community. People dump animals here. There are leftover barn cats that breed, so we have a constant source of "new" intact cats. We moved here in 2008. There were 3 feral cats (vet thinks they were 2 years old). We TNRd them, though it turned out one was female and pregnant, and gave birth exactly 1 hour after dropping her at the vet (four kittens). We got her and her babies (2 of which were female) into a foster network, and they were all adopted out. The two TNRd boys became somewhat social - we adopted one out and adopted one ourselves. 0 cats outside.

That winter when the park closed and the people who were obviously feeding cats left, we saw cats at the garbage dumpsters. So we started trapping.

Bottom line? Since the summer of 2008, we've removed 15 cats/kittens that were adopted out, TNRd an additional 15, have 1 yet to be trapped, and actively have 10 in the colony. We have a 94% sterilization rate (based on the 16 cats that showed up once we were at 0), as there is 1 male that we haven't yet trapped and sterilized.

One of the new cats that recently showed up (and that we TNRd) is clearly a stray - his poster is plastered everywhere. But he'll go into the foster network when kitten season eases up. Three of the younger cats are getting pretty friendly, so they'll likely go too. So we should be able to remove another four of the 10 that are still around.

Unless more cats are dumped, we'll likely be looking at 6 cats in the colony this winter. That's out of a total of 31 cats in the 2 year period. (12 of which were female).

I think you're not understanding how a properly managed TNR program works. Trapping and adopting out is ongoing, so high sterilization rates are possible. TNR programs often fail when it is illegal to feed, so they have to do the TNRing surreptitiously.

BTW, the studies out there indicate that for trap-and-kill to work, you need to trap 50% of the cats to make a dent in the population. For TNR to work, you need to trap 75%. Even the wildlife people don't argue these points, these are the published studies. It may seem a more difficult goal to trap 75% than 50%, but as most people don't want to see the cats killed, if trap-and-kill is the method of animal control, most people won't call to report feral or stray cats. When a community switches to TNR, people call to report the animals, making achieving the goal much more attainable.

I think this is a good example of the difference between theory and practice. I understand why you would think a baited trap is more enticing if there isn't food available on a regular basis, but I'm guessing you haven't worked with a TNR program? Or done any yourself? Because the food attracts the cats to a place at a given time so they can be trapped.

Again - good in theory, but as Amy pointed out, not practical in real-world dollars. Any good-size community can't afford enough animal control officers to manage such a program anyway- another reason trap-and-kill doesn't (hasn't) worked.

That's my biggest beef with The Wildlife Society and other wildlife conservation orgs. They don't want TNR, they want it to be illegal to feed free-roaming cats... yet there aren't enough Animal Control Officers or $ to trap the cats that are out there. So the cats are out there breeding and multiplying.... and they propose no solution, they just oppose TNR and feeding. TNR attracts volunteers (Gary and I do all of this at our own expense and there isn't a low-cost spay/neuter program around here). How many cats would be here now if we hadn't removed any or gotten 12 females spayed?

Great point!

Well, for those that are wondering...

There are a number of studies on cat predation. Most of them are conducted in Australia, a lot of them conducted on islands (because of the potential threat to breeding birds), though there are some pretty well constructed studies done in the UK. So before I include info, I think it's important to point out that there tend to be problems with predation studies. There are a lot of studies that get cited - one of them was a study of four cats. One was a study of six. Those, IMO, are meaningless. But here are the main issues:

• small sample sizes
• method of study recruitment
• data gathering techniques
• methods applied in statistical analysis of data gathered
• assumptions used in "adjusting" the data
• the proportion of scavanged animals in prey collection
• not addressing the extent to which predation is compensatory vs additive

THEN when you GET those numbers, "scaling up" to get to nationwide estimates have their own host of problems (apart from being built on potentially flawed studies of predation rates). These issues include:

• Using average predation rates instead of median numbers (this usually results in inflated estimates when extrapolating to the national level because you usually get about 10% of the cats being exceptional hunters)
• Using inflated cat population estimates
• assuming densities (of birds and cats) are evenly distributed
• Using inflated assumptions for the number of cats that are allowed outdoors
• using inflated estimates of the number of cats that hunt
• Extrapolation predation rates from one habitat into another (taking predation rates from an island study and using those for a continent, for example)

So, with that said...

Studies on continents of reasonable sample size indicate that cats (on average) kill from 1 to 8 birds per year. Now - that's spread across cats that don't hunt. The largest study in the U.S. was conducted by Carol Fiore in 2000. Her study (Wichita, KS) had an average of 4.2 birds per cat per year. She studied 41 cats. But because there were some "super predator" cats in her study, the median number was just 2 birds per cat per year.

As to cats that are allowed outdoors, ABC Birds (the American Bird Conservancy) likes to cite a survey the did in 1997 that showed that 35% of people keep their cats indoors all the time. What they never mention is that 31% said that their cats are kept "indoors mostly, with some outside access." Now - this would mean that 66% of cats aren't allowed to freely roam... meaning 34% of cats are allowed to roam. This number matches up much better with other studies, that indicate 40% (or less) of cats are allowed outside (Lord 2008, Clancey 2003, and the American Pet Products Association annual surveys). So of course the wildlife conservation people always use the 35% ABC number.

Of pet cats, the studies ALL indicate that not all of those allowed outside even hunt. The percent of cats that don't hunt range from 8.6% to 74%, but are grouped around 30%. So when cats are allowed outside, only about 70% of them even hunt.

A lot of people assume that feral cats hunt more birds than pet cats. This would be incorrect. Cats are opportunistic feeders, and the studies indicate that feral cats optimize their hunting strategy... meaning that if garbage is available, they will eat primarily that. But basically hunting cats that prey on birds range from 7.5% to 83%. But this is a number that is really influenced by what's available where the cats are being studied. The 83% number came from a study in New Zealand - which has NO native mammals (except two species of bats).

As to how many feral cats there are... this is something that REALLY needs a real study. There is not a single study that provides a real number based on any scientific method. The Humane Society conducted a survey that estimated there were about 33 million feral cats based on people feeding strays (back in 1993). But all the numbers that get cited now are just people basing a guess off of the number of pet cats. The estimates range from 60 million to 100 million. That said, there is a number based on something resembling a more scientific method. This was done by Merritt Clifton (of ANIMAL PEOPLE), who estimates the winter feral cat population may be as low as 13 million and the summer peak is probably no more than 24 million. His estimates are projected from the numbers of feral cats found in common habitat types taken from a national survey of cat rescuers, and cross compared with shelter intake data (2003). He confirmed in 2004 that the number of feral cats is probably lower than most people estimate based on road kill data he gathered from municipalities around the country. No one uses his number, because it doesn't support the idea that feral cats are a completely out-of-control problem across the country (IMO).

As to TNR vs trap-and-kill... Trap and kill got us where we are, so we can say it's a failed policy. TNR isn't for everywhere. I guess what bothers me the most is when wildlife conservationists attack TNR ... but yet propose nothing else other than killing the cats. There aren't enough dollars to hire enough animal control people to get enough traps out there to make a difference. So they want to ban feeding... but not support TNR, leaving the cats out there to breed and grow.

They like to say that cats are not natural to the environment...

But the fact of the matter is that while predators, cats are one of the very few predators that have the breeding characteristics of a prey species. A very famous study (of six cats) in the 1970s presented the idea that cats may not be a direct threat to populations of small mammals and birds - but they could represent a problem via competition for that food to native raptors. As it turns out - kittens make a good meal for raptors and coyotes (and other native predators).

The other thing most studies don't consider is the extent to which cats are scavenging already dead animals, or killing sick animals.

One last important point about cat predation... cats also prey upon non-native species. A number of studies conducted in Australia indicate that other than in certain areas, they prey primarily on introduced species. In Fiore's study in Wichita, house sparrows and starlings (both non-native to the US) represented the highest proportion of birds killed (26%).

As to the issues of disease... wildlife conservation organizations like to harp on the threat of rabies and toxoplasmosis. Of course TNR actually makes cats a barrier species because of rabies vaccinations. And while the cat IS "the definitive host" of toxo - what this means is that they are the only animal in which toxo completes is sexual cycle, and they are the only animal that can shed eggs via their feces. HOWEVER - toxo also reproduces asexually, and is transmitted orally. So if every cat (including wild ones) were to disappear from the face of the earth tonight, toxo would continue to be a threat, and we would still have to properly cook our meat. But for the wildlife people, that is good P.R., right? I mean - that the cat is the definitive host of toxo sounds really scary!