The Chinese paddlefish belongs to an ancient lineage of paddlefish that has been around for at least 100 million years. But in early 2020, a study concluded that the species has recently gone extinct, mainly because of overfishing and dam construction.
The Chinese paddlefish was one of only two paddlefish species in existence. Its only remaining relative is the American paddlefish, a vulnerable species found in the Mississippi River Basin in the United States.
The Chinese paddlefish was the only species in the genus Psephurus. Researchers had hoped to artificially breed it, but with no individuals existing in captivity and no living tissues conserved, this is no longer possible.
Appearance and diet
Native to China’s Yangtze River, the Chinese paddlefish was thought by many to be the world’s largest freshwater fish, with reports of individuals reaching a mind-boggling 23 feet in length and weighing nearly half a ton. It had a long, silver-gray body and a very large mouth.
With poorly developed eyes, the fish fed with its mouth open, using its long, sword-like snout to sense electrical activity to find prey, such as crustaceans and fish, including gobies and minnows.
These sleek giants, which the Chinese call sword-billed sturgeons, were once commonly seen and caught not only in the Yangtze but also other rivers in China. Their enormous bulk made them a popular target for fishermen and a welcome addition to dinner tables, including those of ancient Chinese emperors. Overfishing caused their populations to decline drastically in the latter half of the 20th century, with an average 25 tons of paddlefish a year harvested in the 1970s.
The death knell for the species probably came with the construction of the first dam on the Yangtze River, the Gezhouba Dam, which began operating in the late 1980s. The dam, located about thousand miles from the sea, blocked the migratory route of the Chinese paddlefish, preventing them from reaching their spawning grounds. This migration route was further disrupted by the construction of the enormous Three Gorges Dam.
China listed the paddlefish as a protected species in 1989. Sightings of the fish continued in the 1990s, but in 1995 the last young individual was seen in the wild. In 2003, an adult Chinese paddlefish was accidentally captured near Yibin, in south-central China. It was tagged by scientists hoping to track its movements, but within hours all signals from the tag were lost. It turned out to be the last of the species ever seen alive.
Localized surveys to find the species were carried out over the following years. In 2018-2019, researchers embarked on a basin-wide biological survey to locate any individuals remaining in the Yangtze. Using various types of nets, sonar, electro-fishing gear, and other techniques to locate any representatives of the species, the team came up emptyhanded and later declared that the species had gone extinct between 2005 and 2010.
The species probably became functionally extinct—that it, it was unable to reproduce—before then, by 1993, according to the study.