In a sad turn of events, another creature totters on the brink of extinction. This time, it is the Chinese giant salamander, or as it is also known by its binomial name, Andrias davidianus. The colossal amphibian has been termed a “living fossil” because little has changed regarding its physical makeup in the past 170 million years. The Chinese giant salamander may actually be made up of five separate species according to Smithsonian, and some may already be extinct.
The critically endangered amphibian can grow up to 5.9 feet in length and can weigh in at a whopping 140 pounds. However, the Chinese giant salamander rarely reaches those dimensions today. The only other salamanders that come close to its size is the somewhat smaller Japanese giant salamander and the North American hellbender that is a great deal smaller.
The amphibian is a deep part of Chinese culture, and its curvy shape is thought to have inspired the Taoist ‘yin’ and ‘yang’ symbols. Factors that are pushing the Chinese giant salamander to the brink, include pollution, habitat loss and overcollection. One key aspect causing its rapid decline is that used it in traditional Chinese medicine; another is that some consider it a delicacy.
Widespread poaching of the Chinese giant salamander is rampant, even though such acts are forbidden under Chinese law. The asking price for them can be more than $1,500 apiece, and that’s quite a motivational price for someone that doesn’t mind breaking the law.
The findings regarding the animal’s plummeting numbers in the wild were amassed over a period of four years by the Chinese Academy of Science’s Kunming Institute of Zoology and from researchers from the Zoological Society of London. The large research effort encompassed 97 sites in 16 of China’s provinces.
The 24 wild Chinese giant salamanders in the study came from three separate river drainage systems. Out of these, 12 were tested, and every one of them demonstrated genetic ties to natives of the Yellow River. This site is the largest and oldest center used for the giant salamander breeding.
After analyzing the genetics of the giant salamanders, the researchers received grim results regarding numbers of wild giant salamanders. The wild population was non-existent, and they concluded that the sample they tested had released or escaped from commercial farms where the animals are harvested for food.
China’s Ministry of Agriculture supports the release of farmed Chinese giant salamanders, and this causes further issues for conservation efforts. Approximately 72,000 Chinese giant salamanders have been released into the wild from the breeding farms since 2008, according to a study in Current Biology.
So the living fossil that survived virtually unchanged for 170 million years, was unwittingly changed by released mates coming from the farms. More to the point, these resulting new breeds were genetically different from the original aquatic animals. Over time, as the farm-bred salamanders mixed or when farm-bred salamanders mixed with wild populations, it hastened the original lineages to extinction.
Amy McMillan is a professor of biology at SUNY Buffalo State College. She compared the scenario of the result after the intermingling of the Chinese giant salamander populations to what resulted when farm and wild-raised salmon on North American coasts intermingled.
“If you have a small population, and you throw in a hundred new individuals, you can genetically swamp out that adapted population in a very short period of time.”
Another concern is that the loss of the salamander can impact other species adversely, causing an imbalance in their populations. The Chinese giant salamander is an apex predator that feeds on small animals such as worms, crayfish, and even smaller salamanders. The total loss of this predator is a complex issue that can cause unknown and potentially negative ripple effects.
All hope may not be lost, however, according to Samuel Turvey, a senior research fellow at the Zoological Society of London. Turvey, an author on both new studies notes that “the latest work could inform a new version of the Chinese captive release programs, focusing on maintaining genetic lineages. The massive numbers of giants in farms—many of which were likely recently taken from the wild—may still contain some of these original genetic lines.”
Andrew Cunningham also shined a dim light of hope about the giant Chinese salamander. Cunningham, deputy director of science at the Zoological Society of London and also an author of both the new studies, said that while all of the Chinese giant salamander population might not be gone, their low numbers found in the wild was not a positive sign.