http://gizmodo.com/feral-cats-are-an...ter-1786809713

Cats are an ecological disaster€”theyre shaping up to be one of the
biggest contributors to the sixth mass extinction. A global analysis
published this week in the Proceedings of the National Academies of
Sciences finds that feral cats have helped drive at least 63 species of
birds, mammals, and reptiles into the dirt over the past 500 years. The
only group of invasive predators thats done more harm is rodents, which
are linked to 75 species extinctions.

All told, invasive predators have contributed to at least 87 bird, 45
mammal, and ten reptile extinctions, which amounts to more than half of
all known extinctions in these groups. Another 596 species are now
threatened by introduced carnivores.