Dr Peter Marra, an academic who is the director of the Smithsonian migratory bird centre in Washington, has written a book called “Cat Wars”, and he’s made a call for all cats to be kept indoors or on a lead to address the “devastating impact” that they have on wildlife.
He goes on to suggest that all feral (unowned) cats should be caught, and if they cannot be adopted, they should be euthanased. He seems to have a vision of utopian cat-free world, where birds can flutter safely without the threat of a stalking cat around the corner.
Dr Marra claims that his views are based on scientific research, and when someone is a “doctor”, they are attached to a “Smithsonian” centre, and they call themselves an “academic”, it’s easy to see why people take them seriously. The problem is that in my opinion, and in the opinion of many others, he is wrong. The balance of scientific research does not support his claims.
As the Cats Protection charity has pointed out, there are many other factors affecting the bird and small mammal species loss that has happened in the past century, including mismanagement and loss of traditional wildlife habitat, climate change and the increased use of pesticides and fertilisers in modern farming. It’s just wrong to single out cats and suggest a major change to their place in society based on an unproven hypothesis.
If his suggestion was put into place, there would be a high risk of the Law of Unintended Consequences kicking in. Suddenly, one of the main predators of rodents in the UK would be removed from the ecosystem. There would be a population explosion of rats and mice, and what effect would that have on wild birds?
A friend of mine recently kept a tally of the prey brought home by his three cats over the previous three months: Sid, Teabag and Murray had differing preferences for various prey items, as you can see from the chalked totals. It’s the ratio of rodents to birds that is most noticeable: between them they took 20 rats and mice, 6 and a half birds (one survived), and 10 frogs. So stopping cats from being outside would have a far wider effect than just boosting the wild bird population.
There’s no doubt that there are specific circumstances where cats should be kept indoors: in areas where there may be ground nesting birds with limited populations (such as certain islands or parts of New Zealand and the USA). But cats have been part of the ecosystem in Europe for thousands of years, and there’s no good reason to change that now.