Drunken wood pigeons have become a nuisance for bird rescue staff in New Zealand, with about 30 having to be rescued in the last two months.

Robyn Webb, of the Whangarei Native Bird Rescue Center says, the kereru birds have been eating guava berries, which have fermented and caused the birds to become intoxicated.

Webb says there has been a lack of food in the forest this year, prompting the birds to feed on the berries. The problem is their inebriated state makes them more vulnerable to predators, like cats and dogs.

The center learned of the birds drunken habits after receiving calls reporting kereru falling out of trees or bumping into windows.