Feral Cats Help Control Rat Populations

This is an important article. Many years ago, as a layman and not a scientist, I made the common sense point that feral cats could be useful to people and so did a visitor who called himself: DoctorM – see his short post. The feral cat could be our friend. I remarked that feral cats could be keeping down rat populations and if the feral cat was eradicated, as many people propose, we could see a surge in rat populations and the consequential impact on society and native mammals that would result. Rats are predators.

In a very comprehensive study of wildlife on many islands off the coast of Australia, where sailors had introduced: black rats, cats and foxes, the surprising conclusion (to the researchers) was that cats help in the survival of some species of native wildlife on these islands because they preyed on black rats which are more destructive of wildlife than the cats. The net result or overall outcome is that the presence of feral cats can be beneficial, which is the exact opposite to what government scientists in Australia have preached for years.

The impact of the feral cat on wildlife species is complicated. The feral cat is now part of the ecosystem and has perhaps become a new wild cat species in Australia, where for a long time, there has been a rather simplistic and crude approach to the feral cat, which is, by-and-large, a hated animal in Australia. The approach has been to kill it as fast as possible. The cry from government is to eradicate it as it kills native species.

But in doing so the research indicates that it could well make matters worse. It reminds me, in fact, of the Great Plague (1665–66) of London, during which it was ordered that the community cats of the city had to be killed because it was believed that they spread the plague. It transpired that the plague was being spread by rats and in killing cats the plague spread faster and with more ferocity.

What the researchers found was that on islands where sailors had only introduced black rats, the extinction rates of native mammals were higher than on islands where the rat, cat and fox had been introduced by sailors. The differences are quite stark. The extinction rates (the rate of killing of native species, to put it simply) were 15 per cent to 30 per cent where only rats were present. The figure dropped to 10 percent when cats were also present. Cats were killing other predators, specifically the rat.

The research also came to a conclusion on the impact of feral cats on native wildlife generally. This is important. The population size of mammals that are native to the islands were only reduced slightly when cats were brought to the islands. So, feral cats, wild roaming cats, do have an impact on native species. They are bound to because they are wonderful predators but it is far less than previously “estimated“. Scientists do have a bad habit of making very poor and biased guesses or guesstimates as to the impact of feral cats on native species.

As a result feral cat haters need to wake up and shape up. Feral cat haters and bird conservationists need to put away their bias and their prejudices and start to think more fairly, logically and sensibly. The feral cat is not the enemy that they believe it is and in any case the feral cat hater should remind himself that it is people who created this resourceful predator.

Associated page: How feral cats affect wildlife