The Animal Health Board is looking at significantly reducing the amount of 1080 poison used for possum control by changing the way it lays bait.
One of the research projects it's funding has shown that it's possible to get a high kill rate in aerial drops while using very little poison bait.
The board's research co-ordinator, Penny Fairbrother, says that instead of broadcast sowing that delivers an even density of bait, the new approach is based on pre-feeding in strips along flight paths which teaches possums where to feed, then laying toxic bait over the same lines.
She says trials have shown that as little as 0.2 kilograms of poison per hectare can be used instead of the 2.5 kilograms per hectare used at present, with at least as effective results.
Ms Fairbrother says they've reached the point where the technique can be tried in actual aerial operations, where the amount of poison used will be reduced to about a quarter of current usage.