The world's largest amphibians, Chinese giant salamanders, were once thought to be widespread but now face imminent extinction due to illegal poaching and hunting as a luxury food, researchers said yesterday.
"The overexploitation of these incredible animals for human consumption has had a catastrophic effect on their numbers in the wild over an amazingly short time span," said co-author Samuel Turvey, a researcher at the Zoological Society of London.
"Unless coordinated conservation measures are put in place as a matter of urgency, the future of the world's largest amphibian is in serious jeopardy."
Vast surveys were conducted in 2013 and 2016 at river sites where the critically endangered salamanders — the size of small alligators and weighing around 64 kilograms — are known to live.
"We cannot confirm survival of wild Chinese giant salamander populations at any survey sites, and consider the species to be extremely depleted or functionally extinct across the huge surveyed area," said the report in the journal Current Biology.
China has a program in place to breed and release giant salamanders back into the wild.
At the few sites where salamanders were seen, researchers could not confirm whether they were wild or farmed.
"Our field surveys and interviews indicate the species has experienced catastrophic range-wide decline apparently driven by overexploitation," said the report.
"The status of wild populations may be even worse than our data suggest. Releases had occurred shortly before surveys at two sites where we detected individuals."
Researchers also reported that what was once thought of as a single species actually represents at least five distinct species — all speeding toward extinction and some may already be gone.
The study suggested that the farming and release of giant salamanders back into the wild without any regard for their genetic differences was putting the salamanders' already dire future at even greater risk.
Releasing hybrids may mean they are poorly adapted for their individual environments, and unlikely to survive.
Salamander farms have sought to "maximize variation" by exchanging salamanders from distant areas, without realizing they are in fact distinct species, said Che Jing from the Kunming Institute of Zoology of Chinese Academy of Sciences.
"Conservation strategies for the Chinese giant salamander require urgent updating," Che said.