New information showing plummeting numbers of orange roughy on seamounts and other features demonstrates why bottom trawling must be banned from these biodiverse areas, say Greenpeace and the Deep Sea Conservation Coalition (DSCC).

Released while the bottom trawling season is in full swing, the review from Fisheries New Zealand shows there are serious sustainability issues for orange roughy, a deep water fish that can live to over 200 years, and aggregate over seamounts at this time of year to spawn.

Greenpeace Aotearoa oceans campaigner Ellie Hooper says urgent action must be taken to protect this species and seamount habitats - which are known biodiversity hotspots.

"Bottom trawling is one of the most destructive fishing methods there is, and right now, trawlers are out dragging their heavily weighted nets over seamounts - targeting orange roughy while they spawn and bulldozing the ecosystems that support them in the process.

"The results are clear - the report shows that groups of spawning roughy are disappearing from where they’re usually found and that bottom trawlers are having to work much harder to catch orange roughy - trawling for longer periods of time while still netting fewer fish."

The only seamount in the review with an increasing number of orange roughy on it is one that has been closed to bottom trawling since 2001.

"All of this information tells us that orange roughy populations have been decimated by bottom trawling, but that they can recover - if the Government closes seamounts and features to bottom trawling."

The report on orange roughy numbers comes just weeks after a Department of Conservation report revealed that commercial fishing, predominantly bottom trawling, has reported dragging up almost 200 tonnes of coral over a thirteen-year period. Of that total coral capture, 86% occurred in fisheries management areas that more or less overlap with ORH 3B - the stock area that is the subject of this review.

"The coral that grows on seamounts is often slow growing and extremely fragile, acting as an essential building block for ocean life," says Hooper.

"Orange roughy aggregate on seamounts while spawning, which is exactly why the fishing industry targets these areas. In doing so, they wipe out the biodiverse habitat and disturb the fish while they are trying to rebuild their numbers.

"Nobody wants a dead, empty ocean. But to avoid that the government has got to stop caving to industry and put ocean health first."

Karli Thomas, campaign co-ordinator at the DSCC, says the orange roughy fishery in the Chatham Rise is a disaster.

"There are huge gaps in the data for key parts of this fishery, but the data we do have indicates dire population levels and spawning aggregations disappearing from seamounts that are open to trawling.

"Seamount habitats that orange roughy rely on have been seriously degraded by decades of trawling, with this fishery responsible for the vast majority of coral bycatch over the last 13 years.

"Despite all that, orange roughy is being exported from New Zealand with a so-called "blue tick" of sustainability from the Marine Stewardship Council - it's absolute greenwash."

Almost 80% of people surveyed support banning bottom trawling on seamounts, and over 80,000 have signed a petition calling for the same.

Thomas says: "It is clear that if we want a healthy and thriving ocean and not barren wastelands devoid of life - then we need bottom trawling gone from seamounts."

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