Tasty animals end up on latest list of threatened species

tuna at Tsukiji fish market

Frozen bluefin tuna are stacked before an auction at the Tsukiji fish market in Tokyo. The fish, coveted for sushi and sashimi, are now on the decline, and the IUCN has just changed their designation to “Vulnerable,” indicating that they are threatened with extinction.

Stewart Butterfield/Flickr (CC BY 2.0)

SYDNEY — Each morning at the famous Tsukiji fish market in Tokyo, large tuna are auctioned off, sold to become sushi, sashimi and other tasty meals. About 80 percent of all the Pacific bluefin tuna caught end up in Japan, and now an alarming number of juvenile fish are included in that number. The young fish are killed before they’ve had a chance to reproduce, and that’s contributing to a sharp decline in the species — about 19 to 33 percent over the last 22 years. That’s one of the reasons why the International Union for Conservation of Nature just changed the official status of the fish from “Least Concern” to “Vulnerable” in the latest update of its Red List of Threatened Species.

The IUCN is racing to assess 160,000 species by 2020 and is nearly halfway there. This new update, released November 17 at the IUCN World Parks Congress, reassessed many species, such as the tuna, and added many more to the list. With those new additions, the total number of officially threatened species — those rated Vulnerable, Endangered or Critically Endangered — is now 22,413.

Notable among the additions this time are the number of edible species: The cyanide-laced Chinese pufferfish, known as the popular Japanese dish fugu that can kill if prepared improperly, enters the list as Critically Endangered due to a 99 percent reduction in its numbers. The American eel faces plenty of threats — including pollution, habitat destruction and parasites — but is also declining because poachers are stealing the eels for seed stock for eel farms, largely due to the decline of the Japanese eel. Both eel species are now considered Endangered. And while the Chinese cobra has probably never landed on your dinner plate, it’s popular enough in Hong Kong markets to drive its numbers south and garner the snake a Vulnerable listing.

The Red List “is a wake-up call,” said Jane Smart, global director of the IUCN Biodiversity Conservation Group and director of the IUCN Global Species Program. “In many ways, if a species finds itself in a threatened category, it’s a good thing because it does draw attention to action that needs to be carried out.” The Red List, compiled by thousands of expert volunteers, brings together the best data about these species, so the threats are often already known. The decline of the Bluefin tuna, for instance, drew fisheries groups earlier this year to pledge to reduce their catches.

But the growing number of threatened and, worse, extinct species is alarming. This time, two species — a Malaysian snail and what was the world’s largest earwig — were declared extinct due to habitat destruction. The snail was found on a single limestone hill that was destroyed by a mining company. And the Saint Helena giant earwig disappeared from its South Atlantic home after nearly all the surface stones that could provide the insect with shelter were taken away for use in construction.

The IUCN list now has 832 extinct species and 69 that are extinct in the wild. According to the current strategic plan for the Convention on Biological Diversity, a global agreement, the extinction of known threatened species should be prevented and their conservation status should be improved or at least maintained by 2020. “Almost no country is heading in the right direction,” noted Simon Stuart, chair of the IUCN Species Survival Commission.

Sarah Zielinski is the Editor, Print at Science News Explores. She has a B.A. in biology from Cornell University and an M.A. in journalism from New York University. She writes about ecology, plants and animals.

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