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IUCN Red List Reclassifies Whale Sharks as Endangered

Although seeing a whale shark in the wild is on the bucket list for many divers and snorkelers, our chances to do so may be dwindling.

Many of us have encountered whale sharks in the wild. Those who haven’t yet usually rank the experience high on the bucket list. However, we may be running out of chances to see these magnificent animals in their natural environment. Earlier this year, the International Union for Conservation of Nature (IUCN) officially declared the whale shark endangered.

IUCN Red List Reclassifies Whale Sharks as Endangered

The IUCN is the world’s largest and most diverse environmental network. The IUCN Red List classifies species into categories ranging from Least Concern to Extinct. The whale shark was previously listed as Vulnerable, but the worrying results of a recent study prompted officials to upgrade the species’ rating to Endangered. Only two other categories (Critically Endangered and Extinct in the Wild) stand between the whale shark and extinction.

How did the whale shark become endangered?

In order to be classified as Endangered, a species must fulfill one of a number of criteria. The species must have suffered a population decline of 50 percent or more over the last three generations, the causes of which have not yet been addressed. This is true for the whale shark, with researchers estimating that their numbers have halved in the past 75 years. Director of IUCN’s global species program Jane Smart says of the whale shark’s status that “it is alarming to see such [an] emblematic species slide towards extinction.”

She goes on to say that the new assessments emphasize the need to protect whale sharks and other at-risk species. Conservation action in countries like India, the Philippines and Taiwan has helped to stem the species’ decline. But in other areas of the world, both small and large-scale fisheries take the sharks with impunity. In southern China, for example, fishermen routinely target whale sharks, hoping to cash in on the country’s lucrative shark-fin trade. Even in countries that protect whale sharks, illegal poachers often take them.

What next?

At the moment, CITES Appendix II lists whale sharks. This theoretically places strict limits on the international trade of threatened species. However, according to Red List assessor and whale shark expert Dr. Simon Pierce, “more needs to be done domestically to protect whale sharks at a national level.” Regional fishermen are not the species’ only problem. Trawlers and purse-seine fishermen frequently catch them accidentally. Global overfishing may affect their food sources, and ship strikes often injure or kill them.

The whale shark is not the only marine species whose conservation status has recently changed for the worse. Unregulated fishing has also caused the dramatic decline of the winghead shark, also known as the slender hammerhead. Fishermen target the shark heavily throughout its range. It is also particularly susceptible to entanglement thanks to its oddly shaped head. Although data is limited for the slender hammerhead, scientists estimate that populations have declined by more than 50 percent over the past three generations. As such, the IUCN has also upgraded its status to Endangered.

In September, Hawaii will host the IUCN World Conservation Congress. The congress meets once every four years; this year’s session will see a complete update of the IUCN Red List. The IUCN is likely to reassess other marine species as part of the update. Hopefully, unlike the whale shark and the slender hammerhead, some of those species will show signs of recovery.