The orange roughy and a ‘cautionary tale of over-exploitation’

Sunday, 16 March 2025

It was a rescue mission that wasn’t quite as marketed.

Orange roughy stocks collapsed in the 1990s due to overfishing, leading to drastic catch reductions and the closure of some fisheries.

Over a decade later, new assessments began to indicate signs of recovery and by 2016, three fisheries (around 70% of catch) were certified sustainable.

Two years later, some quotas were cautiously increased and the conservation effort was trumpeted around the world.

But the claims of recovery were premature. A review by the Ministry of Primary Industries in October 2023 revealed a “flat or declining trend.” Officials suspected the commercial catch had been set too high for close to a decade.

The sweet, buttery fish is caught by bottom trawling, and the report revealed crews were having to work harder to catch them, towing for far longer periods and yet still catching fewer fish.

New Zealand seafood companies self-suspended Marine Stewardship Council certification for the delicacy caught off the nursery grounds of the Chatham Rise – an underwater plateau extending 1,400 kilometres east of Banks Peninsula – which reached near collapse in the 1990s.

And the Government reviewed allowances for the ORH 3B fishery, which stretches from the South Island’s east coast to Southland, and includes the Chatham Islands and subantarctic waters.

David Parker, then-minister for oceans and fisheries, cut the catch by 40% in September 2023.

But some ocean conservationists believe that wasn’t enough. And now an application for a judicial review of that decision is heading to court.

The case will be heard in the High Court in Wellington in July.

The Environmental Law Initiative will argue that the decision was made unlawfully and failed to take an ecosystem-based approach to fisheries management.

Tess Upperton, ELI’s senior legal advisor, said: “it’s a cautionary tale for our tendency to over-exploit our natural ecosystems”.

Remarkably, until about 40 years ago, the orange roughy was relatively undisturbed by fishing. For millennia, it thrived in the cool deep waters around New Zealand, Australia and the Mid-Atlantic Ridge, off Namibia.

Known as slimeheads, they were given the more palatable name orange roughy in the 1970s when scientists found an abundance off New Zealand.

Brick-red, with a firm, mild flesh, the discovery sparked a deep-sea bonanza. Because they gather in large groups, commercial fishing crews could easily haul in tonnes using trawl nets.

The species was hunted to the edge of commercial extinction. By the 1990s scientists realised the fish grow incredibly slowly and don’t breed every year.

Their lifespan is extraordinary – with some living beyond 200 years old.

But when harvested in huge numbers, the species is slower to recover than fish with a shorter lifespan which reproduce earlier.

“These are slow-breeding fish that only reproduce once they are well into their twenties and can live for 200 or more years,” Upperton said.

“We know very little about the way these fish react to trawling and have no idea about the current status of the main stock.

“To enable a genuine recovery of orange roughy populations, catch limits need to be based on the precautionary principle and fishing techniques should not destroy habitat.”

In a decision paper prepared for Parker, Fisheries NZ officials argued for a precautionary approach of a 40% cut.

But ELI argues the information was flawed because it didn’t provide Parker with “best available information on the trawl footprint”.

The paper said that the decreased fishing effort would lead to a smaller trawl footprint.

But ELI argues that catch rates for orange roughy were flat or declining; and accordingly the area of the seafloor trawled for orange roughy has increased because a larger trawl footprint was required to catch a smaller amount of stock.

“The Minister erred by relying on misleading advice and by failing to take into account the best available information on the trawl footprint,” ELI’s statement of claim states.

The group also claims the decision didn’t consider the impact of bottom trawling on the wider ecosystem nor how adverse effects could be avoided or mitigated.

“New Zealand fishing vessels are responsible for around 80% of the global orange roughy catch,” Upperton said. “That means the future of this fish is in our hands.”

ELI, with Ngāti Kaharau and Ngāti Hau Hapū ki Hokianga, successfully challenged a 2023 catch limit for crayfish in Northland.

Fisheries Minister Shane Jones declined to comment.

The commercial fishing industry supported a precautionary catch limit for the fisheries area labelled ORH3B in 2023.

And the following year, some quota owners also sought a decrease, pending more science, in the ORH7A area, to the west of New Zealand.

Known as Challenger, that fishery was closed in 2001 for a decade after being plundered.

Jones cut the catch limit by more than half (57%), the most cautious option mooted by officials.

Industry body Seafood NZ’s chief executive Lisa Futschek couldn’t comment on the case while it is in front of the court.

But she said the commercial fishing industry is “committed to the long-term health and vitality of New Zealand's orange roughy fisheries”.

It contributes “significantly” to facilitating robust science in support of sustainable management of fisheries, she said.

That included commissioning Australia’s Commonwealth Scientific and Industrial Research Organisation to undertake an acoustic biomass survey of the spawning aggregations in ORH 3B.

“We presented these results to the Government working group for approval and use in an updated stock assessment,” she said.

With the Marine Stewardship Council, modelling was developed to map different biomass trajectories. “This enables long-term catch management procedures for orange roughy,” Futschek said.

“And with very little definitive research about the lifespan of orange roughy – one of the longest-lived commercial fish species – we are investigating processes designed to determine the age of orange roughy,” she added.

The orange roughy is also making waves in the annual Fish of the Year challenge. The species leads the whale shark, with longfin eel in third place.

Voting in the competition, run by the Mountains to Sea Conservation Trust to raise awareness of endangered fish, closes Sunday, with the winner announced Monday.

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