An authoritative new report reveals the considerable carbon cost of bottom trawling, with environmentalists calling it a "damning wake-up call" for the commercial fishing industry.

The report, released today by the Parliamentary Commissioner for the Environment, reveals that bottom trawling is the largest threat to releasing carbon stored in the seabed around Aotearoa.

Greenpeace Oceans Campaigner Ellie Hooper says the report is more proof that bottom trawling bans are urgently needed."The seafloor contains one of the largest stores of carbon on Earth, and by dragging heavy, weighted nets over it, the bottom trawling industry releases carbon back into the water," says Hooper..

"The fishing industry is in denial about bottom trawling - not only are they trashing biodiversity hotspots, ripping up tonnes of ancient coral every year, but they’re also intensifying climate change. In the meantime, they’re cynically peddling the myth that their business is carbon friendly."

Seafood New Zealand released research earlier this year claiming that wild-caught seafood has the lowest carbon footprint compared to other animal proteins. However, the study left out the carbon impact of bottom trawling the seafloor.

Karli Thomas of the Deep Sea Conservation Coalition says it’s time the industry dropped its inaccurate and misleading claims.

"Whether they’re destroying precious ocean ecosystems on seamounts or dredging carbon sinks on the seafloor, the cost of bottom trawling is abundantly clear, but for decades, governments and the commercial industry have delayed transitioning away from it.

"This is a fishing method that should be left where it belongs - in the last century. We need urgent leadership on bottom trawling and commitments to removing it from the most sensitive areas first - seamounts and features in the deep sea and from the Hauraki Gulf."

The study found that carbon stocks were higher and more likely to be disturbed on the deeper continental shelves and slopes, such as the Chatham Rise, as well as in mud-filled bays like the Hauraki Gulf.

Barry Weeber of ECO says: "The report makes plain that deepwater areas from 200 - 1500m depth contain a substantial portion of New Zealand’s seabed carbon, but these areas are also being heavily fished by bottom trawlers - and there lies the harm.

"Whether you look at it from a biodiversity or climate perspective, this fishing method has dire consequences for the ocean. We urge the incoming government to stop kicking the can down the road and take bold action to create bottom trawling bans."

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