Chinese paddlefish declared extinct
A team of researchers at the Chinese Academy of Fishery Sciences in Wuhan, China has declared the Chinese paddlefish (Psephurus gladius) as extinct. In their paper published in the journal Science of The Total Environment, the group describes their study of the large fish and outline why they believe it has gone extinct.
The Chinese paddlefish has been declared extinct in a study published in Science of the Total Environment. The fish was a very large freshwater fish—they were on average 10 feet in length, but some were as large as twice that length—they got their name from their large, protruding snout. They lived in the Yangtze River and its tributaries in China.
The researchers report that the large fish, sometimes referred to as the "panda of the Yangtze River" was a popular catch in the river system up until the 1970s. They suggest its extinction was due to overfishing and loss of habitat.
The study by the team involved reviewing fish catch records and also carrying out field studies over the years 2017 to 2018. Their field studies involved setting up nets, catching fish and canvassing fish markets. They report that they found no evidence of the presence of Chinese paddlefish. They also report that the last known sighting of a live specimen was back in 2003—the last known dead sighting was in 2007. Not only has the fish gone extinct, they note, but there are no specimens in captivity and no tissue samples were stored; thus it cannot be revived through cloning. The researchers have concluded that the paddlefish is gone for good.
The Yangtze, Asia's largest river, originates in an eastern part of the Tibetan Plateau and meanders westward for 6,300 kilometers before finally meeting the East China Sea at Shanghai. The paddlefish were prominent in many parts of the river system and were regularly fished. Things became difficult for them when the Gezhouba Dam was built in 1981—it split the paddlefish population in two and prevented those fish trapped below it from spawning. Few were sighted after 1995.
The researchers suggest the loss of the paddlefish should serve as a lesson in fish conservation—efforts to save the fish did not begin until the fish was already gone. They suggest more surveys are required more often to allow scientists to track the state of aquatic species.
More information: Hui Zhang et al. Extinction of one of the world's largest freshwater fishes: Lessons for conserving the endangered Yangtze fauna, Science of The Total Environment (2019). DOI: 10.1016/j.scitotenv.2019.136242
Journal information: Science of the Total Environment
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