Minister for Oceans and Fisheries Shane Jones is scrapping the limit on the number of sea lions the fishing industry is permitted to accidentally kill.
The move comes as the Department of Conservation (DoC) reports a 24 percent decline in sea lion pups in the main population on the subantarctic Auckland Islands.
What's left of the New Zealand sea lion population mostly lives on the subantarctic islands where they compete for food with the commercial squid fishery.
They are sometimes killed by being trapped in trawl nets.
"We know, based on the most recent pup count for rāpoka New Zealand sea lions, that the population is in a sustained state of decline," World Wide Fund for Nature NZ chief executive Kayla Kingdon-Bebb said.
"[Based on] their population count, there's... no justification for removing one of the last remaining safeguards we have for keeping these animals safe," Kingdon-Bebb said.
There had been an official limit in place on the number of sea lion deaths that could occur before the fishery had to close. But that limit has just been scrapped by Jones.
"I think that we've got bigger things to worry about. There's probably more sea lions being predated upon by killer whales than politicians," Jones said.
The fishing industry and Ministry for Primary Industries said sea lion exclusion devices are fitted to nets and incorporate an escape hole to allow sea lions to pop out rather than drown.
But scientists said there's not sufficient evidence to show they're working.
"They're being ejected out of the net, most of them, and we don't know if they're being ejected dead or alive or they're going to die of their injuries," zoologist Liz Slooten said.
Jones said the data shows the fishing industry only catches about two sea lions each year.
But Newshub understands scientists are concerned that evidence is gathered by the fishing industry and kept secret.
"If there are only two to three sea lions being caught per year, then I don't understand why Shane Jones is refusing to set a limit of 33 sea lions," Slooten said.
Jones was not interested in speaking further about sea lions on Thursday, walking off saying, "Free Willy, Free Willy, Free Willy".
It puts in question New Zealand's goal of zero bycatch deaths of protected species by 2050.
