Cats are listed among the 100 worst non-native invasive species in the world.
According to the British Ecological Society, globally, cats have contributed to the extinction of at least 40 bird species, 21 mammal species, and two reptile species.
The Migratory Bird Center, Smithsonian Conservation Biology Institute estimates that free-ranging domestic cats kill 1.3–4.0 billion birds and 6.3–22.3 billion mammals annually.
Cats kill anything that moves, no matter how well-fed or whether neutered. It’s so bad in Australia, they’ve taken to poisoning, trapping and hunting cats...