There are more than 90 million pet cats in the U.S., the majority of which roam outside at least part of the time. In addition, millions of stray and feral cats roam our cities, suburbs, and rural areas. Scientists estimate that free-roaming cats kill hundreds of millions of birds, small mammals, reptiles and amphibians each year. Cat predation is an added stress to wildlife populations already struggling to survive habitat loss, pollution, pesticides, and other human impacts (see: Domestic Cat Predation On Birds And Other Wildlife). Free-roaming cats are also exposed to injury, disease, parasites, getting hit by cars, or becoming lost, stolen, or poisoned. Millions of domestic cats are euthanized each year because there are not enough homes for them. Cats can also transmit diseases and parasites such as rabies, cat-scratch fever, and toxoplasmosis to other cats, wildlife or people (see: The Great Outdoors Is No Place For Cats).