Do We Really Know That Cats Kill By The Billions? Not So Fast

[alarimer]

63. Yes, cats are an introduced species and the DO have an impact.

Think about this for a minute. There are millions of pet cats out there and many, many more millions of strays. If each one only killed one animal a year (which may be true for house cats, but not for strays), that's still millions of animals being killed. And that is a low-ball estimate. Logic would dictate that it would actually be much larger. Even excluding cats with homes from the picture because they are probably less likely to hunt frequently because they have a reliable food source, that still leaves an impact of millions of animals killed by strays or feral cats.

Now, the impact of such a loss is hard to evaluate. It probably depends on which species are being impacted the most. After all, there are probably BILLIONS of house sparrows out there. A few million less is probably no big deal. And house sparrows are an introduced species anyway. They have other predators and other pressures. But imagine a species that is in trouble or has declined. In that event, any predation by cats or other animals may well be the difference between survival of the population and extinction.

If cats are introduced into a more fragile ecosystem rather than one that has already been disturbed (like your backyard), it may have more dire consequences on populations in those kinds of places. Especially places like the Galapagos (which, to my knowledge, does not have an issue with cats, but possibly other introduced species) or similarly unique habitats. You can see that those birds would be sitting ducks (so to speak) for predators such as cats.

Feral cats can also be a problem because of disease. Not only could they spread disease to pets, they could also spread diseases to wild animals. The same goes for dogs and any other domesticated animals.