Feral Cat Myth: "Feral cats kill mostly pest birds like starlings and sparrows."

There's just one hitch in the scheme to control nuisance birds with the introduced cat corps: Only a minority of birds killed every year by cats in the United States are the wily starlings and house sparrows. Many more victims are the native songbirds and neotropical migrants, the colorful little ones that fly north to the United States and Canada each spring to nest and try to keep their dwindling populations alive.
Placing an admittedly arbitrary value of $30 on each slain songbird, "Biological Invasions" editor David Pimentel sets the cat-killed tally at $17 billion a year. That doesn't count, he notes, all the native small mammals, amphibians and reptiles killed by feral cats and outdoor pet cats.
(Sources: "Biological Invasions: Economic and Environmental Costs of Alien Plant, Animal and Microbe Species," David Pimentel, editor; Cornell Lab of Ornithology; Cornell Cooperative Extension.)
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