1400 tahr culled from South Westland National Park

Photo / File

The Department of Conservation is about a third of the way through its planned tahr control programme for the year, with most of its efforts focused this winter on the West Coast.

A report to the Tai Poutini West Coast Conservation Board shows DOC hunters have flown 60 of the 195 hours budgeted for the annual aerial cull.

The Himalayan mountain goat numbers have to be kept as low as possible in national parks because of their destructive impact on tussock and mountain plant habitat, and all tahr inside park boundaries are targeted in the annual cull.

But outside the Aoraki-Mt Cook and Westland National Parks, DOC leaves the big male animals prized by trophy hunters.

It focuses instead on reducing herd numbers and keeping them within a defined feral range across thousands of hectares of public conservation land.

DOC operations director in Wellington Dr Ben Reddiex said more than 100 tahr were shot this year outside the feral range, to the north.

Staff were still collating overall numbers but 1400 animals had been shot in the Westland National Park so far, Reddiex said.

"We will be putting out maps showing identifiable male tahr sightings on our website later this week to help hunters plan their next trip and we'll be doing a review of the control operation to date with the Game Animal Council at the mid-point, later this month."

The tahr carcases are not recovered and there have been concerns about the risk to kea which feast on them, sometimes consuming lead shot in the process.

But DOC no longer used lead ammunition, a spokesman said in an update for conservation boards this month.

The change to non-lead buckshot struck a glitch last year when it was found the lighter shell cases had hit helicopter tail rotors a couple of times, leaving grooves.

Experts advised there was no safety risk but the shell cases could cause costly damage to the rotor blades.

The problem had been resolved by modifying the shotguns used in the tahr cull to change the shell ejection pattern, DOC reported.