There are over 66 million pet cats in the United States. A recent poll shows approximately 35 percent never go outside. That leaves more than 40 million pet cats free to kill wildlife. Loss and fragmentation of wildlife habitat is by far the leading cause of declining bird populations. Domestic cats are numerous, efficient, non-native predators who contribute to the decline.
Habitat fragmentation provides cats easier access to wildlife.
Rather than havens for wild creatures, these smaller tracts can be death traps. Some presume that a cat's killing certain animals, such as field mice, is beneficial, but native small mammals matter to ecosystems. Mice and shrews are an important food source for birds such as the great horned owl, red-tailed hawk, and American kestrel. Pet cats have huge advantages over native predators. They get protection from disease, predation, competition, and starvation, factors that control native predators such as owls, bobcats, and foxes.