A pest control programme on land near Lake Wanaka has eradicated almost 700 pests - including a cat compared in size to a panther - in little more than a year.
The 300ha of land includes the 49ha Glendhu Bluffs Conservation Area and adjacent privately owned land, such as the exclusive Emerald Bluffs subdivision.
The tally of 696 pests eradicated by the end of December comprised 300 rabbits, 217 possums, 45 cats, 34 hedgehogs, 33 stoats, 20 rats, 12 hares, nine mice and five ferrets.
The work is being done by Doug Beech of Matukituki Natives, who said "pockets" of rabbits attracted predators such as cats and stoats.
He described cat numbers as "quite scary" because he had cat traps on only one 40ha property. The cats became "quite cunning" and were difficult to catch once they became wary of a trap.
"I know there are a few around I still haven't caught."
The biggest cat he had caught was a "massive" black one, as long as the fish bin fixed to the back of his bike.
"This one looked like a big panther."
Mr Beech is using a "really effective" kill-trap for cats developed for Canada's fur trade. He considered it important to reduce cats, stoats and ferrets at the same time as reducing rabbit numbers.
"If the rabbits get down a bit [in number] they [other predators] then target the native birds even more. So it's a whole sort of vicious cycle."
The work being done by Mr Beech is funded by the Longview Environmental Trust in conjunction with the Department of Conservation.
Trustee John May says he has already noticed a substantial increase in birdlife in the area.
The successful breeding by a pair of karearea [New Zealand Falcon] was considered to be one example of the benefit of the pest control work.
Falcon numbers are declining generally because of predation and a reduction in the size of their habitat.