There are just 1,000 individual Yangtze finless porpoises left in the wild, according to a new report. That's less than half of what a similar survey of the porpoises found six years ago.
The rapidly dwindling numbers have conservationists worried that the species could vanish from the wild as early as 2025.
"The species is moving fast toward its extinction," said Wang Ding, head of the expedition to count the porpoises and a professor at the Institute of Hydrobiology at the Chinese Academy of Sciences.
Yangtze finless porpoises, the only freshwater finless porpoise in the world, live mainly in the Yangtze River and China's Dongting and Poyang lakes. They are threatened by shrinking food resources and man-made disturbances like shipping traffic.
The expedition, which took place over 44 days last fall, comes after a similar trek along the Yangtze in 2007 failed to find any surviving Baiji dolphins, a close relative of the finless porpoise that was subsequently declared functionally extinct.
The new report showed that some finless porpoises are splintering off into relatively isolated groups, which could hurt their ability to reproduce. The scientists also noted that more of the animals seemed to be flocking to wharf and port areas, perhaps to look for food.??
"They may risk their lives for rich fish bait resources there," Wang said in a statement from the World Wildlife Fund, a conservation group involved in the report. "But busy shipping traffic close to the port areas poses a threat to the survival of finless porpoise."
Other finless porpoises seemed to be avoiding human disturbances and were spotted gathering in dense groups in waters not open to ship traffic. But that strategy could backfire — in these waters, the animals risk getting caught in illegal fishing traps.
As part of their conservation recommendations, the report authors urge for a year-round fishing ban in all river dolphin reserves, and for new reserves to be established in Poyang Lake and along the Yangtze.
The report, called the 2012 Yangtze Freshwater Dolphin Survey Report, was released Thursday (March 28).
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