Sushi Edging Pacific Bluefin Tuna Toward Extinction

The global food market is placing 'unsustainable pressure' on the species and others, a conservation body warned.

The Pacific bluefin tuna, a fish used in sushi and sashimi dishes, is at risk of extinction as the global food market places "unsustainable pressure" on the species and others, a conservation body warned Monday.

The bluefin tuna joined the Chinese pufferfish, American eel, Chinese cobra and Australian black grass-dart butterfly on the International Union for Conservation of Nature's (IUCN) "red list" of threatened species.

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The updated list was released by the IUCN at its once-a-decade World Parks Congress in Sydney as it called for better management of protected areas, where some of the decline in species levels has taken place.

"Each update of the IUCN 'red list' makes us realise that our planet is constantly losing its incredible diversity of life, largely due to our destructive actions to satisfy our growing appetite for resources," IUCN's director-general Julia Marton-Lefevre said.

"But we have scientific evidence that protected areas can play a central role in reversing this trend," she added.

For this year's list, the IUCN assessed 76,199 species, with 22,413 judged to be under threat.

The Pacific bluefin tuna moved from the "least concern" threat category to "vulnerable" as the species is threatened with extinction due to its use in Asia's sushi and sashimi markets, the Swiss-based group said.

As most of the fish caught are juveniles that have not yet reproduced, the population has dropped by 19-33 percent over the past 22 years.

It called for fisheries to implement conservation and management measures for the Western and Central Pacific Ocean.

The American eel is reeling from the impact of climate change, parasites, pollution, habitat loss and commercial harvesting, as well as having been hit by the high levels of consumption of its counterpart, the Japanese eel.

The IUCN categorised the Chinese cobra as "vulnerable" with the population falling 30-50 percent over the past two decades -- another species hurt by its popularity as a food source.

"The growing food market is putting unsustainable pressure on these and other species," the IUCN's biodiversity head Jane Smart said.

"We urgently need to impose strict limits on harvesting and take appropriate measures to protect habitats."

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Another species added to the list was the Malaysian snail Charopa lafargei -- named after the French construction giant Lafarge, which has agreed to try and limit its quarrying activities in the snails' habitat -- the report said.

Two species, the Malaysian mollusc plectostoma sciaphilum and the St Helena Giant Earwig, were declared extinct due to habitat destruction.

But there was good news for two amphibians in Colombia's Ranita Dorada Reserve -- both members of the poison dart frogs family -- which improved in status and are now categorised as "vulnerable" due to conservation efforts.

The World Parks Congress, which will outline a global agenda for protected areas for the next decade before closing on November 19, comes a month after the member nations of the UN's Convention of Biological Diversity met in South Korea to lay out a roadmap to halt species extinction by 2020.

The World Wildlife Fund said in its Living Planet Report published in September that there has been a 52 percent decline in mammals, birds, reptiles, amphibians and fish overall from 1970 to 2010.

A bluefin tuna.

Atlantic Halibut

April 25, 2012 -

Whole Foods, the Texas-based natural foods supermarket, no longer carries fish considered to be unsustainable. The Whole Foods ban includes fish that is either overfished or caught in a harmful way, according to their website. The popular Atlantic Halibut made the list, though the company will still sell Atlantic cod that is caught by hook and line or gillnets. "Stewardship of the ocean is so important to our customers and to us," David Pilat, the global seafood buyer for Whole Foods told the New York Times. "We're not necessarily here to tell fishermen how to fish, but on a species like Atlantic cod, we are out there actively saying, 'For Whole Foods Market to buy your cod, the rating has to be favorable.'" Here's a look at the list of fish that the superstore no longer sells and why.

Octopus Whole Foods uses ratings set by the Blue Ocean Institute, a conservation group, and the Monterey Bay Aquarium in California. The ratings are based on factors including how abundant a species is, how quickly it reproduces and whether the catch method damages its habitat.

Imported Wild Shrimp "At Whole Foods Market, we've been saying that our mission is to sell only wild-caught fish that has been responsibly caught. For a few years now, we've used color-coded sustainability ratings, from green (best choice) to red (avoid), to help you make an informed choice. Now we're putting our mackerel where our mouth is: To support greater abundance in our oceans, we're no longer carrying red-rated wild-caught seafood!" the company wrote on its blog.

Tuna (from specific areas and catch methods rated "red") On their website, Whole Foods says that they stopped selling "species that were extremely depleted in the oceans, such as orange roughy, shark and bluefin tuna" years ago. The company uses the sustainability ratings of the Marine Stewardship Council (MSC).

Rockfish According to the Monterey Bay Aquarium, "In recent years, reduced fishing has allowed many rockfish populations to recover from low levels. Gear concerns remain, however -- trawl-caught rockfish should still be avoided."

Swordfish Some of the gear used to fish swordfish "accidentally catches sea turtles, seabirds and sharks," according to the Monterey Bay Aquarium.

Skate Wing Skates are in the overfished category. Most are also caught with bottom trawls, which result in high levels of accidental catch.

Sturgeon According to Monterey Bay Aquarium, "Sturgeon farmed in the U.S. is a good alternative to most wild sturgeon, whose populations have seriously declined due to overfishing for sturgeon eggs (caviar)."

Tautog Also known as black fish, Tautog are considered a "vulnerable" species. They are found close to shore on hard-bottom habitats, occasionally entering brackish water.

Trawl-Caught Atlantic Cod Fishermen often catch cod with bottom trawl, large nets that skim across the seafloor. Trawling, according to the Monterey Bay Aquarium, "damages marine habitats and produces bycatch."

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Turbot A cousin of Pacific halibut, turbot are a right-eyed flatfish -- as they develop, their left eye migrates across the top of the skull toward the other eye on the right side. Turbot are yellowish or grayish-brown on top and paler on their underside.

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Gray Sole Gray sole, a flatfish bottom-dweller, has experienced heavy fishing pressure from domestic and international fleets over the last half-century, according to Monterey Bay Aquarium.

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