The above is an example of what you get when your understanding of the natural world comes from repeated 'Bambi'-viewings.  Nature is one hundreds of million year-long PARADE of extinction that stretches from before trilobites down to the present day.

Sustained eradication campaigns against feral cats are particularly effective on islands.  The Island Conservation and Ecology Group, Instituto de Ecologia del Universidad Autonoma de Mexico, Centro de Investigationes de Biologias de Noroeste and offices of the Areas Naturales Protegidas in 1994 helped local folks eradicate feral cats from 26 islands off the northwest Mexican coast. In five years they'd succeeded on 16 of them. Twenty-six endemic reptile, 21 endemic mammal and one endemic bird species recovered once the cats were gone.

For two other endemic birds it was too late — they're extinct.  I'd really, really hate it if we became the next species to become extinct because of overweening affection for a disease-ridden "pet".