Related BBC sites

Page last updated at 09:55 GMT, Tuesday, 29 September 2009 10:55 UK
Giant fish 'verges on extinction'
By Jody Bourton
Earth News reporter

Chinese paddlefish (Psephurus gladius)
A river giant vanishes

One of the world's largest freshwater fish is on the verge of going extinct.

A three-year quest to find the giant Chinese paddlefish in the Yangtze river failed to sight or catch a single individual.

That means that the fish, which can grow up to 7m long, has not been seen alive for at least six years.

There remains a chance that some escaped the survey and survive, say experts, but without action, the future of the species is bleak.

The concern for the Chinese paddlefish is that its fate will parallel that of the Yangtze river dolphin, a large mammal species that was once abundant in the Yangtze river system, but has recently been declared extinct.

Chinese paddlefish (Psephurus gladius)
Some people call it the 'elephant fish' and we found out it swims on the surface of the water like a whale
Professor Wei Qiwei
Chinese Academy of Fisheries Science

A number of fish species vie for the position of the world's largest freshwater fish, including the arapaima (Arapaima gigas) of the Amazon river and the Mekong giant catfish (Pangasia