One Of The World's Largest Freshwater Fishes Declared Extinct

KEY POINTS

The giant Chinese paddlefish was one of the largest freshwater fishes in the world
They were widely fished in the 1970s, and the building of a dam split the population in two
Researchers say the species should be considered extinct under the IUCN Red List criteria
Conservation efforts to save endangered species in the Yangtze river are needed

Researchers declared the Chinese paddlefish as extinct, over a decade after the last known sightings of the species. It was one of the largest freshwater fishes in the world.

Extinct

A team of researchers from the Chinese Academy of Fishery Sciences in Wuhan, China has declared the Chinese paddlefish (Psephurus gladius) as extinct. The last known sighting of a live specimen of the species was back in 2003, while the last known dead sighting was in 2007. Since then, no one has reported seeing the species.

For their study, the researchers reviewed fish catch records and even carried out field studies in 2017 and 2018. The field studies involved trying to catch the fish themselves as well as canvassing fish markets, but they neither caught any Chinese paddlefish nor saw any in the markets. In fact, the researchers found 332 fish species during their survey. However, not a single one of them was a Chinese paddlefish.

The researchers estimate that the Chinese paddlefish was already functionally extinct or unable to reproduce by 1993, and went completely extinct between 2005 and 2010. Unfortunately, the Chinese paddlefish did not only go extinct in the wild, but there are also none in captivity and no tissue samples of the species were stored. As such, there is no hope to resurrect the species through cloning.

This means that the Chinese paddlefish is gone for good.

Conservation

Also called the “panda of the Yangtze River,” the Chinese paddlefish was one of the largest freshwater fishes in the world, reaching up to 7 meters in length. They were prominent in many parts of the Yangtze River and were popular fish to catch until the 1970s. However, the building of the Gezhouba Dam in 1981 split the population in two and prevented the ones trapped below from spawning. By 1995, only a few of the species were observed.

The researchers conclude that the Chinese paddlefish likely went extinct due to overfishing, lack of reproduction, and habitat fragmentation. This extinction, according to researchers, serves as a lesson in fish conservation, showing what happens when efforts to save a species come too late.

“The delayed extinction of Chinese paddlefish resulted from multiple threats, suggesting that optimizing conservation efforts on endangered Yangtze fauna is urgently needed,” the researchers wrote.

The study is published in Science of The Total Environment.