Estimates for how many birds cats kill in the United States vary almost as widely. The lowest estimates are around 100 million and go up to the 2.5 billion, though the consensus seems to hover around half a billion. What this leaves out, of course, is that many vulnerable bird species are particularly threatened by cats (and, alas, sometimes dogs as well), a non-native predator that often kills small animals for the fun of it.
Cat defenders say that this is all bogus. If cats didn't slaughter the birds, natural predators would. Maybe, but they are, uh, natural predators, and nature's a big deal for environmentalists, right? Or have I been reading the wrong magazines? They also claim that losing habitat to development is a bigger threat than cats. OK, but even if that were true in some places, why should that get cats off the hook?
This raises an important insight into what is really going on here. The objection to DDT and pesticides has a great deal to do with the fear of technology and material "progress." For example, Carson's memory is still invoked regularly by the anti-pesticide movement today. Anti-pesticide activists claim that some 67 million birds die every year from such chemicals. In other words, compounds that make food cheaper and more abundant for everybody kill between 10 and 20 percent of the number of birds killed by cats every year. And yet, environmentalists are terrified of making cats a major issue, because it will split the movement. An official at the World Wildlife Fund calls the cat issue a "third rail" for environmentalists.
Whether DDT was as bad for birds as Carson and her heirs claim is still the subject of great controversy. What is not controversial is that the bans and regulations Carson's work implemented came with real costs. In the Third World, malaria continues to kill millions because Carson-induced DDT phobia. The bias against pesticides produces lower food yields with no proven benefits for human health.
Meanwhile, the contribution of feral cats is 100 percent aesthetic. We like kitties. This raises an outrageous double-standard. Dogs - our closest allies in the animal kingdom - can be shot for harassing wildlife or livestock. But free-loading cats are protected when they massacre birds for sport. Where's the justice?
This isn't to say that there aren't other important reasons why spring is becoming more silent. But the loss of habitat, pesticides and the advent of wind power all bring significant social benefits. While tolerance for the multitude of feral, often diseased, wild cats is pure, spoiled self-indulgence.