Poison drop delayed as by-kill numbers tallied

A planned 1080 drop over New Zealand’s largest farm has been pushed back as deer hunters collate by-kill numbers from a previous drop.

An aerial poison drop over 22,000 hectares of Molesworth Station, between Marlborough and Canterbury, was planned for June, but the OSPRI website said the drop had been ‘‘deferred’’.

New Zealand Deerstalkers Association branch treasurer Wayne Smith said he believed the postponement was related to their deer head count at the end of last year, as they tried to better understand the impact of 1080 on the deer population. OSPRI was approached for comment. Smith said using the poison on the highcountry farm was like ‘‘using a sledgehammer to crack an acorn’’.

Association president Bill O’Leary said they were happy with the deferment.

‘‘It gives us time to analyse why we got such a by-kill and to look for ways to mitigate the effect on deer if a second drop went ahead,’’ O’Leary said.

The club paid about $25,000 for scientists to prepare a report on the number of deer being affected by the controversial aerial 1080 programme.

Late last year, eight helicopters used GPS to spread 2 kilograms of 1080 per hectare over 61,000 hectares of the station.

Two helicopters were hired by the hunting club to perform a methodical aerial sweep after the drop to count deer carcasses.

Smith said the results of the survey were still forthcoming, with scientists still preparing a report from the data. ‘‘The survey is to gather scientific data on the number of by-kill related to aerial 1080 drops and to inform public debate.’’

The Department of Conservation managed Molesworth Station as a recreation reserve and approved the operation in support of OSPRI’s TBfree programme, aiming to eradicate bovine tuberculosis in possums by 2040.

In 2003 Molesworth Station had more than 140 cases of TB detected within the cattle herd and had the longest standing TB-infected cattle herd in New Zealand.

The station was a rugged block and, according to OSPRI, most parts were unsuitable for ground control methods.

Smith said the survey and anecdotal reports of deer by-kill in the area along with the possibility of a new cost-effective method of applying deer repellent deferred the drop at the station.

There had been consultation between OSPRI, DOC, Landcorp and the NZ Deerstalkers Association after the first drop. ‘‘We’ll be happy to have some good info at hand to discuss with OSPRI and DOC,’’ Smith said.

‘‘One of the issues we had is I don’t think OSPRI did a survey on possum numbers or density before and after the aerial drops to actually be able to measure if it worked.

‘‘We’ll see what happens next year.