Calls have been made for the fishery around Campbell Island to be temporarily closed after 16 endangered sea lions were killed by fishing boats in three weeks.
Rather than halt the southern blue whiting fishery, officials have ordered boats to use exclusion devices on nets to keep sea lions from being trapped.
"The fatality of 16 sea lions from fishing is unacceptable," Conservation Minister Nick Smith said.
Otago University zoologist and sea lion expert Bruce Robertson said it would be better to shut the fishery until the issue was sorted and reopen it next year.
He said there was no evidence that the sea lion exclusion devices worked as assumed. It was possible the sea lions were killed and then were passively ejected through the net opening, rather than swimming out like they were supposed to.
"Also, do the fisherman on those boats know how to use the devices, or will they be doing more harm than good?" he said.
"The most appropriate avenue would be to close the fishery this year, sort the problem and then start again next year."
The Greens have also called for the fishery to be closed.
"Sixteen New Zealand sea lion deaths are 16 too many, given that these creatures are critically endangered and their population is declining," Green Party conservation spokeswoman Eugenie Sage said.
She said the Government was being "reckless" to rely on the exclusion devices.
"There is considerable uncertainty about the condition of sea lions once they escape fishing nets via exclusion devices, so the best and surest way to protect the endangered sea lion is to stop lethal fishing methods in its habitat," she said.
Sea lions have been at risk from the squid fishing near the Auckland Islands.
"This run of 16 fatalities in the Campbell Island fishery is a backwards step and requires we increase our efforts to protect these sea lions," Smith said.
Minister for Primary Industries Nathan Guy said there was a trawling exclusion zone around Campbell Island.
In the past, the fishery had three fatalities a year.
"These 16 fatalities in the first three weeks of a six-week fishing season is unprecedented," Guy said.
"I welcome agreement of the industry to use the exclusion device and their additional efforts to minimise the time trawl gear is able to be accessed by the sea lions to reduce the ongoing risks."
The New Zealand sea lion has an estimated population of between 10,000 and 12,000.
About 80 per cent of the population live on the Auckland Islands and 20 per cent on Campbell Island.
The species is listed as "vulnerable on the International Union for the Conservation of Nature's red list and as "nationally critical" on New Zealand's threat classification system.
- © Fairfax NZ News
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