The Department of Conservation (DoC) will this week begin a controversial programme to cull 10,000 Himalayan tahr over the next eight months.
Conservation Minister Eugenie Sage had earlier flagged her intention for a major control operation, after aerial monitoring indicated that numbers of the wild alpine goats in the mid to lower South Island had ballooned, destroying flora and fauna.
The plans were met with opposition by hunting groups who challenged the monitoring methodology, and also by the National Party, but today Sage said they would go ahead after discussions with hunters and others in the Tahr Liaison Group (TLG).
While the target of 10,000 remained, the plan had been revised to provide for a "staged" control operation, with increased reporting to the TLG.
DoC and hunters would now work together to cull an initial 6000 animals over the next few weeks, to stop the population swelling further and wiping out more native plants.
DoC would then assess what further action was needed to reach the 10,000 animal target by next August.
"Two years of aerial monitoring has shown that the numbers of Himalayan tahr in the mountain lands of the Southern Alps have ballooned to damaging levels with estimates of more than 35,000 animals," Sage said.
"This is more than three times the number of animals permitted by the long established Himalayan Tahr Control Plan."
"Urgent action" was required to protect the environment.
"To be very clear though, there is absolutely no plan to eradicate tahr completely," she added.
"Even after this control work is done, there will still be thousands of tahr available for guided Himalayan tahr hunting and hunting tourist ventures."
DoC had been consulting hunters and others on the draft operational plan and how to best undertake the control operation.
"Finalising the operational plan has involved input from every organisation with an interest in Himalayan tahr through the Tahr Liaison Group," she said.
"It has been a constructive and productive effort by all parties."