World's largest amphibians face imminent threat of extinction

The critically endangered Chinese giant salamander, well known as the world's largest amphibian, now faces the imminent threat of extinction in the wild, due in no small part to the demand for the animals as luxury food, warn researchers.

The findings, published in the journal Current Biology, showed that illegal poaching of the amphibians is widespread.

For the study, the researchers conducted field surveys from 2013 and 2016, in an effort that was possibly the largest wildlife survey ever conducted in China.

The data revealed that populations of this once-widespread species are now critically depleted or extirpated across all surveyed areas of their range.

The researchers were unable to confirm the survival of wild salamanders at any survey site.

"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 one of the researchers Samuel Turvey from the Zoological Society of London (ZSL).

"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," Turvey added.

In another study, published in the same journal, the researchers reported that giant salamanders are not one species, but possibly as many as eight.

The discoveries highlight the importance of genetic assessments to properly identify the salamanders, the researchers said.

It also suggests that the farming and release of giant salamanders back into the wild without any regard for their genetic differences is putting the salamanders' already dire future at even greater risk.

In fact, some of the five newly identified species may already be extinct in the wild, the study said.

"We were not surprised to discover more than one species, as an earlier study suggested, but the extent of diversity - perhaps up to eight species - uncovered by the analyses sat us back in our chairs," said Jing Che from the Kunming Institute of Zoology, Chinese Academy of Sciences.

"This was not expected," Che said.

With individuals weighing in at more than 63 kgs, the salamanders inhabit three primary rivers in China, and several smaller ones.

While the harvesting of wild salamanders is already prohibited, the findings showed that farming practices and existing conservation activities that treat all salamander populations as a single species are potentially doing great damage, the researchers said.

Salamander farms have sought to "maximize variation" by exchanging salamanders from distant areas, without realising they are in fact distinct species, Che explained.

As a result, she said, wild populations may now be at risk of becoming locally maladapted due to hybridisation across species boundaries.

--IANS

gb/bg