Poisoned bait has been dropped on a 6500ha trial area on Stewart Island/Rakiura
Last year, the Department of Conservation announced plans to drop 1080 bait to reduce the feral cat population endangering the southern New Zealand dotterel, of which there are about 105 birds left.
Cats will feed on the carcasses of rats and possums killed by the bait.
Aerial 1080 is the most effective tool to control predators including rats, possums, and feral cats over large areas and in rugged terrain, Doc says.
Bait dropped in hunting blocks will contain deer repellant.
Last month, two applications of non-toxic pre-feed bait were dropped to encourage rats and possums to eat the bait.
Zip operations director Duncan Kay said the 1080 drop started on Sunday afternoon when bait was distributed across about 1000ha of the 6500ha elimination trial area.
The drop continued yesterday and will finish today, weather permitting.
Remote cameras were placed in the trial area several weeks before the operation.
‘‘By comparing the number of rat, possum and feral cat detections before and after the operation, we will get an indication of the rate of bait uptake,’’ Mr Kay said.
The cameras would also help determine the number of animals that died.
How fast the animal died would depend on the species, body weight and how much bait it ate. Rats usually died within 2.5 to 36 hours and possums within five to 18 hours. In both cases, the pests died faster in cold conditions.
The operation was taking place in a remote area at a time of low use.
As there was no regulatory requirement to bury carcasses, it was likely they would lie where they died, he said.
In phase two of the operation, 1080 bait will be dropped on 43,000ha and begin with a non-toxic pre-feed in late July or early August.
No precise dates have been decided, but timing would be fine-tuned to achieve the maximum benefit for pukunui, he said.
