Zero Invasive Predators (Zip) is trying to rid the Perth River catchment of possums.
It has already done the prefeed, which was to be followed by a 1080 drop with double the usual dose of poison.
However, the Greymouth Star reported last Thursday that kea had been seen eating the baits.
Doc Western South Island operations director Mark Davies, of Hokitika, said today Zip had now completed tahr culling in the area, which had been authorised as part of Doc's work in managing the tahr population under the Wild Animal Control Act.
Zip had hoped the kea would then eat the tahr carcases rather than the poisoned baits.
"As per a clause in the permission given to Zip to undertake the operation, Doc is reconsidering the permission for Zip to apply aerial 1080 because of the recent evidence of kea interaction with the prefeed bait," Mr Davies said.
"This decision will be made in the coming weeks."
It would need to balance whether the risks to kea were outweighed by the potential long-term benefits for the birds in the research area, and the potential to remove all pests from an area, Mr Davies.
That would mean less aerial 1080 would be required in the future.
A kea repellent could be sown prior to dropping the toxic baits, as another mitigation method, he said.
"Tahr carcases have already been collected and distributed in order to be prepared if a decision is made to continue with the operation. There may be further mitigation measures required."
- By Laura Mills
