The Department of Conservation will start culling pests such as rodents and possums in the Catlins in order to protect mohua and other birds.
The Battle for our Birds operation in the south-eastern corner of the South Island begins on Saturday with an aerial application of non-toxic baits over 10,100 hectares.
It comes after monitoring results revealed rapidly rising rat and mice numbers throughout the Catlins' silver beech forest.
"This will trigger a stoat plague over the summer," said Catlins ranger Cheryl Pullar.
This is a risk to mohua, also known as yellowhead, who are nesting and trying to raise their young during the season, she said.
Last year more than 47,000 hectares of forest underwent aerial pest control, which the department says resulted in mohoa numbers increasing to the highest level recorded since the population suffered a big decline 15 years ago.
In line with safety procedures, warning signs regarding the presence of poison will be present at all entrance points to the area.
There are two phases to the pest control: first non-toxic pre-feed bait is distributed, which is then followed by biodegradable poison 1080-laced cereal baits around five days later.
The Catlins is one of 25 operations using aerially applied 1080.
A total of about 700,000 hectares of conservation land - mostly beech forests on the South Island - will be subjected to the pest control.
So far DoC has completed 427,186 or 61 percent of its bird-saving operations.
Read more: http://www.3news.co.nz/nznews/1080-to-cull-pests-in-catlins-2014110807#ixzz3IbmrDBa4