The Green Party is calling for an end to commercial fishing of longfin eels, as Parliament's environment select committee declares the creature in a "perilous state".
But those who hold quota to fish longfin eels say their numbers are healthy.
The Department of Conservation (DOC) considers longfin eel in decline due to loss of wetlands and historical commercial fishing practice.
"They are at risk, they are a species we need to look after," says Julie Underwood, senior keeper of ectotherms at Auckland Zoo.
They're the largest and longest-lived freshwater eels in the world and breed only once at the end of their life, far away in some of the deepest oceans between Tonga and New Caledonia.
The adult eels then die, and the larvae travel back on ocean currents over 10 months to New Zealand shores, where hatched eels swim back to their freshwater habitats.
Wairarapa man David Famularo brought a petition to Parliament to bring the longfin eel into the Wildlife Act because he believes it is "a remarkable and culturally significant taonga".
"They have a lot of personality and character, and they're very charming," Famularo says.
"As a species they're incredibly unique.
"The Department of Conservation has said it's going to review the Wildlife Act and that's excellent, but we also just need to get more protection for the longfin eel so we're not in a position where it's too late to do anything about its survival."
After hearing submissions on Famularo's petition, Parliament's environment select committee recommended the catch limit of longfin eels be reviewed, while the Greens want to go further.
"We have a responsibility to protect it, the Greens believe we should stop commercial fishing and allow the species a chance to recover," Green MP Eugenie Sage says.
But longfin eel North Island quota holder Mike Holmes suggests the Greens "do something useful".
"Eels are not a problem. Our water management could improve, especially around regional councils," Holmes says.
Longfin eels are unusual given they're a threatened species that's also managed under the Fisheries Act and have been in the quota system for 20 years.
Conservationists say that's at odds with their threatened status.
"We shouldn't be gambling with the future of such an important species," Sage says.
A 2013 report from the Parliamentary Commissioner for the Environment found the longfin eel population had many small eels and few large eels.
But those who fish the longfin eel for a living like Holmes say that's changed thanks to the quota system doing as it was intended.
He said he recently landed a 13kg eel, which he released as fishers aren't allowed to take anything above 4kg.
"Big eels, big longfins, they're like the white pointers of the freshwater world and we're getting a lot of them now," Holmes says.
"It's pretty cool to see."
Holmes says there is no reason to halt commercial fishing of longfin eels.
"For the Government to halt the fishing of longfin eels, they'd essentially have to close down the fishery and to do that under the Fisheries Act they'd have to buy us out, which they could do but I don't think Government's going to do that."
He does support the recommended review of the total allowable catch.
"Overall the longfin fishery is in good shape and it's improved a lot in the last 20 years."
Holmes says farmers fencing waterways has helped eels recover, but has a bone to pick with the removal of invasive willow trees from wetlands.
"Greens want to remove willows because they're not native, but willows are really critical for longfin."
Eel expert Julie Underwood says the main threats to longfin eels are habitat loss and pollution. But she admits it's probably not great that they're being fished.
"It's an interesting one to have an endangered species still being fished, so yeah it's probably not super beneficial to the population to have individuals being removed, but I'm not super aware of how they're assessing that."
Underwood says that's part of the problem - until better data is gathered on the mysterious creature, it's hard to know how they're really faring.
