Philanthropic economist Gareth Morgan is calling for the eradication of cats from New Zealand.

"The fact is that your furry friend is actually a friendly neighbourhood serial killer," his new Cats to Go website, set up by the Morgan Foundation, says.

The site says cats have contributed to the extinction of nine native bird species and impacted on 33 endangered native bird species.

CLAWS OUT: Gareth Morgan wants action.

It goes on to say that killing cats is not necessary but is an option.

"We appreciate the fact that you have an emotional connection with your pet and that pet ownership is a rewarding experience.

"But there's a real problem with cats - they kill for pleasure, and most of that killing is out of your sight so probably out of your mind.

"If you think New Zealand's native species are precious and should be fostered then it's important you be a responsible cat owner.

"That means keep them inside 24 hours a day and if that's impractical then when the time comes ensure this is the last cat you ever own."

Morgan also suggests other ways to reduce the impact cats have on native bird populations.

"I am advocating responsible pet ownership, not for people to bop their pets on the head. To me a responsible pet owner has their cat neutered, keeps it well fed and indoors as much as possible, and puts a bell on them. Then when their cat dies I think people should consider not replacing it".

Councils also need to step up and manage cats like they do already with dogs, he said.

"All cats should be registered, chipped and neutered, while setting live capture cage traps on your property and turning the miscreants over to the local authority should be encouraged."