Low river levels are putting pressure on Otago's trout fishery, Otago Fish and Game says.
It was monitoring waterways closely, particularly in Central Otago, and salvage work would be undertaken where practical for the rescue of adult fish, Otago Fish and Game Council chief executive Niall Watson said.
In dry seasons, the impacts of low summer flow conditions, such as high water temperatures, reduced habitat and vulnerability to predation by shags and herons, were intensified.
Fish and Game supported the minimum flow conditions set by the Otago Regional Council on irrigation takes as they protected core ecosystem values.
While many restrictions were coming on, Fish and Game still expected significant deaths among juvenile trout in smaller tributary streams.
The situation in Central Otago was exacerbated by the existence of water takes based on century-old mining privileges which did not have environmental flow restrictions on them, he said.
Those privileges expire in 2021.
