Cats and Birds

Domestic cats (Felis catus) can make wonderful pets. But when allowed to roam outdoors, cats threaten birds and other wildlife and disrupt ecosystems. The best way to help protect birds and other wildlife is to keep cats indoors.

Piping Plover with chick, (c) Michael Stubblefield

Cats: Threat to Birds & Biodiversity

Outdoor domestic cats are a recognized threat to global biodiversity. Cats have contributed to the extinction of 33 species and continue to adversely impact a wide variety of other species, including those at risk of extinction such as Piping Plover.

The ecological dangers are so critical that the International Union for the Conservation of Nature (IUCN) lists domestic cats as one of the world’s worst non-native invasive species.

Bird decline drivers from the 2014 State of the Birds report

Cats #1 Threat to Birds

Predation by domestic cats is the number-one direct, human-caused threat to birds in the United States and Canada, as the graphic on the left details. (2014 State of the Birds report.)

In the United States alone, outdoor cats kill approximately 2.4 billion birds every year. Although this number may seem unbelievable, it represents the combined impact of tens of millions of outdoor cats. Each outdoor cat plays a part.

Cat with a bird, Talya Photo/Shutterstock

Instinctive Predators of Wildlife

Even well-fed cats will hunt and kill. Upon reflection, most cat owners will have observed this behavior. When a cat plays with a feather toy or laser, it is practicing predatory behaviors. When these behaviors continue outdoors, the results are deadly for birds and other wildlife.

Unfortunately, the mere presence of cats outdoors is enough to cause significant impacts to birds. Because cats are recognizable predators, their presence near nesting birds has been shown to reduce the health of chicks and decrease nest success.

Stray cat on Oahu, Lauren Orr/Shutterstock

Cats & Hawai’i

Hawai’i was originally a paradise for birds. Geographic isolation and the absence of mammalian predators resulted in remarkable biodiversity, including such iconic species as the ‘I’iwi and Maui Parrotbill.

Unfortunately, the introduction of cats to the Hawaiian Islands in the late 1700s has resulted in the widespread predation of unique native birds and broad environmental contamination affecting people and wildlife alike.

  • Cats are indiscriminate predators that kill endangered species such as ‘Ua’u (Hawaiian Petrel), Palila, Nene (Hawaiian Goose), and many other species.
  • The presence of outdoor cats in Hawai’i also contaminates the environment with the parasite Toxoplasma gondii. Recent deaths of species that do not directly interact with cats, such as Hawaiian monk seals and otters, suggest that neighborhoods, beaches, and waterways may be heavily contaminated.

Our Hawai’i Cats PSA provides an overview of the special issue of cats in our 50th state. View the video.

Scientific Literature on Cats & Birds