Ferrets as pests

Ferrets like other mustelids as ermine prey on indigenous wildlife of New Zealand. First introduced in 1879 as a means to control feral rabbits, ferrets caused great concern among the New Zealanders they started to hunt the land birds of the island.

This was because New Zealand’s birds evolved without contact with mammalian predators, and are therefore easier prey for them.

The owners of ferrets in New Zealand defended ownership saying the animals released were polecat ferret crosses the wild European polecat from fur farms.
Today, domestic cats cause more damage in wild bird populations that ferrets, since they are usually castrated at a young age 6 to 8 weeks and remain confined in their houses.

However, many locations around the world have banned the possession of ferrets as pets because of the problems encountered in New Zealand.