Cats are one of the predators that were introduced by humans to the Hawaiian Islands. The State of Hawai'i Department of Health estimates that there are 500,000 cats on the island of Maui. Thousands of these are feral, non-domesticated animals left to hunt and capture prey in the wild.
Feral cats (Felis catus) inhabit most environments on the Hawaiian Islands, including wet, montane forest environments where native birds are found. Cats and cat signs (scat or tracks) have been observed in Hanawi Natural Area Reserve, The Nature Conservancy's Waikamoi Preserve, and Haleakalā National Park by Maui Forest Bird Recovery Project staff members as well as outside researchers. Cat scat found within Hanawi contained the remains of both nestlings and adults of native and non-native bird species. Cats utilize a wide range of food resources including eggs, nestlings, and adult birds. Forest birds that forage in the understory, such as the Po'ouli and Maui ‘Alauahio, are especially vulnerable to cat predation.
Predation by feral cats has had serious negative effects on populations of avifauna and have been associated with extinctions of various types of species throughout the world.
Effective predator control of these animals helps to alleviate their impact on forest bird populations. Feral cat colonies should not be supported not only for the birds, but for human and cat health. Spaying and neutering pets, keeping pets on leashes also helps. See the American Bird Conservancy's website for downloadable materials about Keeping Cats Indoors.
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