High country sheep have been sprayed with a kea repellent in a trial designed to make the sheep-riding parrots feel sick and prevent them from harming stock.
The Kea Conservation Trust sourced funding from the Cincinnati Zoo and its own operational funds (from public donations) to run the trials on Wakatipu high country stations in 2011-12 and in May-June this year.
Trust chairwoman Tamsin Orr-Walker said the trust would like to hear from more farmers wanting to be involved with further trials.
The only costs to farmers would be bringing the stock in, which could be done during regular mustering, and providing shearing quarters accommodation for trust volunteers, she said.
In this year's trial, sheep were sprayed with anthraquinone/lanolin repellent and results looked promising as the sheep were later examined and no evidence of damage or flagging was found.
It was the first time in six or seven years no sheep were killed by kea strike on that particular farm.
Acoustic recorders were also used in the high country blocks to establish whether keas were in the area.
The repellent ''makes the bird feel queasy and hopefully realise it [the sheep and wool] is not a good thing to eat'', Ms Orr-Walker said.
The repellent did not damage the wool or cause any health problems for sheep, she said.
''We know kea were visiting the area but we can't directly attribute it to the repellent - but it is a really positive result.
''The farmer was pleased and is happy to continue with the research,'' Ms Orr-Walker said.
Kea strike - kea riding the sheep, then eventually eating the wool, fat and flesh - has been a problem for high country farmers for many years.
Historically Otago, Canterbury Lakes and the Mackenzie Country have had problems with kea strike and years ago the Government introduced a bounty on birds, leading to them becoming nationally endangered.
Farmers who have kea strike problems can apply to the Department of Conservation for permission to cull keas, but it is something most farmers are reluctant to do.
Ms Orr-Walker said often only a small number of kea caused problems.
Sometimes the damage to sheep and sheep deaths were greater on one farm than another.
As the trust and other researchers have limited data on kea strike, a biologist from Massey University, Clio Reid, has put together a survey for high country farmers to gain information
on the prevalence of kea strikes, how strikes have changed farmers' farming practices and what they have done to prevent them.
Ms Reid said some farms had had low numbers of kea strike in the past 10 years - maybe annual losses from one to just a handful of sheep - while others had had much higher levels, including one she was aware of which lost about 400 sheep in one year.
''There are still sporadic attacks, with some farmers reporting problems of kea strike over eight to 12 years.''
''There are a few farms that have had to stop using their back blocks as it is not economical as they lose sheep to kea.
''Doc do what they can to help out and giving sheep five-in-one clostridial inoculations can prevent infection caused by kea,'' Ms Reid said.
Kea seemed to strike mostly during autumn and she had never had any reports of them hurting lambs, she said.
Information gained from the survey will be published in a scientific journal and given to Doc and farmers.
If anyone wishes to be involved with the research they can contact Ms Orr-Walker on info@keaconservation.co.nz
A copy of the survey is available by emailing clio.reid@clear.net.nz or through the Otago Merino Association.
Ms Reid is hoping for responses from as many high country farmers as possible by the end of November.
- by Yvonne O'Hara