by Michael Broad
We simply don’t know how feral cats affect wildlife except on the rare occasions where feral cats have inhabited small islands. There is a lot on this subject and the position of people is very polarized and the discussions can get quite hot. A typical recent example (April 2010) is the case of the feral cats of Los Angeles, where a judge banned the city's support of TNR of feral cats on an application to the court by bird conservationists. The judge made a bad decision in my view because it was not clear to him/her as to how feral cats affect wildlife.
This is because there are people who want to wipe out the feral cat because it ostensibly slaughters millions of native animals every year and there are people like me who say, “hang on”, lets take a more balanced view on this emotive subject.
The truth is we just don’t have a good handle on the problem. All I ever see on the internet is:
- People quoting numbers with no reference to the research. The numbers seem to be plucked out of thin air or at best are estimates. This sort of situation normally comes from the anti feral cat brigade and a lot of people from this brigade live in Australia. Sorry, I am not anti-Australia. I like Australia and the Australians but….
- Very little sound research.
- Guesses as to the number of feral cats that exist.
- Guesses as to the number of feral cats that are euthanized each year. I see figures from 2.2 million to 14 million in the USA alone.
- An almost totally omission as to the impact that humans have on the populations of wildlife species through (a) increased traffic (b) increased building programs (d) increased human populations (e) habitat loss (the biggest impact) (f) farming’s impact through pesticides and loss of habitat (g) careless cat ownership (h) the fact that we, people, created the “feral cat problem”.
- A failure to factor in feral dog populations.
- A failure to factor in other predators including birds preying on birds.
- A failure to study and understand how the feral cat fits in to the ecosystem and whether its demise will improve wildlife species populations.
- Studies that have been carried out may and sometimes are biased to support political objectives.
OK there is more but I have made my point. We don’t really know how feral cats affect wildlife. For this reason we:
- Need to be cautious when discussing the subject.
- Need to do more large scale research.
- The research should be apolitical and truly scientific.
One example of what I personally don’t like about some articles on this subject is on this page:
Feral cats kill birds (link broken 2012)
It contains wild assertions such as, “They kill hundreds of millions of birds and other wildlife, and it's not going to be easy to get rid of them”. Sure, cats kill birds but we don’t know how many (see below).
This page:Stray Pet Advocacy (new window)
is far more balanced and it refers to research carried out in 2001 (Berkely, 2001), in which it was found that, ”the feline hunting style of wait and pounce is unsuitable for flying birds. Frequently, the flying birds consumed are injured or already dead”. (I have quoted verbatim for accuracy and given a link in exchange).
The Department of Sustainability and Environment (DSE) of the government Victoria, Australia, says, “In Victoria, on average, each pet in reference to cats can kill 25 creatures every year; this adds up to 12.5 million creatures every year”. But there was no reference to where this information came from.
One thing for certain that we do know, cats are carnivores so, yes, they will have an impact on wildlife. But how much? We don’t even know how many feral cats there are so how can we work out how feral cats affect wildlife?
Update 15th April 2010.... I refer at the beginning to cases of feral cats killing native wildlife on small islands. On these islands the native fauna has evolved without being preyed upon. For example, small islands where sea birds nest on the ground. There are cases of feral cats causing the extinction of island bird populations. I refer to the saddleback and New Zealand's Kakapo (a flightless parrot) which as at 2002 were on the brink of extinction mainly because of predation by feral cats (ref: Wild Cats of the World - Sunquists - 'WOW').
There are also cases of how feral cats have caused extinctions of populations of island reptiles. Between 1974 and 1976, 15,000 iguanas on the Turks and Caicos islands were killed by cats (and dogs?) introduced by a hotel who perhaps wanted to control rodents (ref: WOW).
One the Galápagos islands 'the endemic marine iguana' is endangered on some islands because of predation by cats, dogs, pigs and rats (ref: WOW).
We should remind ourselves that in these rare cases the problem is of our making as we introduced the cat to these places. I am also skeptical as to the veracity of some of these reports and surveys. There is a lot of bias in such reports. The truth is hard to come by.
See a lot of visitors' submissions on the feral cat - you'll like them
See some great personal stories about people and rescued feral cats (scroll down once you have reached the linked page).