Auckland Council and the Department of Conservation are currently working to eradicate deer that were illegally released in Omaha Scenic Reserve, near Mount Tamahunga.

A source tipped a DOC worker that six deer had been released, information which was supported by sightings of them in March.

Four of the six were shot, and the council are confident that they will be able to hunt down the remaining two.

Feral deer are a legally declared pest species in Auckland. Deer cause damage to native forests by feeding on forest plants, trees and seedlings. When deer populations get too large, plants like schefflera, broadleaf, three-finger, hen and chicken fern and lancewood are all but removed from the ground tier in forest understoreys. 

Deer in New Zealand have no natural predators (apart from hunters), so if left alone, the population can grow fast. 

While it is unknown how the deer got there, the most common reasons for deer turning up in areas include releasing them from captivity - an easy option for removing them from a farm - or recreational hunting.

It is illegal to release deer into the wild and perpetrators can face up to $15,000 in fines. The public is encouraged to report sightings of feral deer by emailing [email protected] or calling 09 301 0101.