Protect birds by reining in cats

Although some cat owners still let their pets roam free, the felines are a leading cause of bird mortality, and bird and cat proponents agree that both species are safer if cats are reined in.

The good news is that cat owners are, increasingly, keeping their felines enclosed.

"The cat realm is catching up to the dog realm in this," says Danielle Bays, community cats program manager for The Humane Society of the United States. The number of cats kept indoors has increased dramatically in recent years, she says.

Cats kill an estimated 2.4 billion birds in the United States and Canada every year, according to researchers from the Smithsonian and the U.S. Fish and Wildlife Service.