Development of the Chinese giant salamander Andrias davidianus farming industry in Shaanxi Province, China: conservation threats and opportunities

Abstract

The Chinese giant salamander Andrias davidianus is endemic to China and is Critically Endangered, largely because of overexploitation for food. This species is an expensive delicacy in China, and a rapidly growing industry to farm the species has developed throughout much of the country, centred on the Qinling Mountain region of Shaanxi Province. During a  workshop on Chinese giant salamander conservation, which involved a range of stakeholders from across China, it became clear that the conservation community knew little about the salamander farming industry and whether it posed actual or potential threats or opportunities for conservation of the Chinese giant salamander. We therefore conducted a series of investigations to understand the industry better. Our results indicate that although farming of Chinese giant salamanders has the potential to be a positive development for conservation by supplying market demand with farmed animals, it is currently more likely to threaten than support conservation of the species, with continued overexploitation and the potential added impacts of infectious disease and genetic pollution arising from farming practices such as movement of animals across the country and the release of untreated farm wastewater and farmed salamanders to the wild.

Distribution and Host Range of Ranaviruses

“…Dr. Lingbing Zeng has been working with several Chinese giant salamander farms, and has documented the virus across 11 Chinese provinces (L. Zeng and J. Ma, Yangtze River Fisheries Institute, unpublished data). The emergence of this ranavirus in China is a serious conservation threat (Cunningham et al 2015 ).…”

Imminent extinction in the wild of the world’s largest amphibian

“…Chinese legislation prohibits harvesting wild CGS populations, but China's Ministry of Agriculture supports widespread releases of farmed animals by provincial fisheries offices and licenced breeding companies, a strategy that fails to meet IUCN reintroduction guidelines and may be harmful to wild populations (e.g., mixing genetic lineages; spreading pathogens) [4]. CGS now detected in the wild might therefore represent releases or escapes.…”

“…The CGS, a top predator in Chinese freshwater ecosystems, reaches 1.8 metres and represents an ancient lineage (Cryptobranchidae) that diverged >170 million years ago [3][4][5]. Endemic to China, it occupied a huge distribution across several watersheds but has declined through overexploitation and habitat loss, and is considered Critically Endangered and a global conservation priority for maintaining evolutionary history [3].…”

“…Establishing a robust status assessment for widely-distributed species requires costly, co-ordinated activities involving multiple methods, and range-wide threat assessments are therefore often extrapolated from potentially non-representative local studies [3]. The Chinese giant salamander (CGS; Andrias davidianus), the world's largest amphibian, is thought to occur across much of China, but populations are harvested to stock a farming industry supporting a new domestic luxury food market [4]. Between 2013-2016, we conducted field surveys and interviews in 97 counties across 16 Chinese provinces or equivalent administrative units, representing 7.47 person-years of fieldwork and data collection from 2,872 respondents in possibly the largest wildlife survey conducted in China.…”

Introduction: History and Future of Ranaviruses

“…In captivity, 100 % mortality of hosts is commonly observed likely due to abundant hosts, guaranteed transmission, and stress associated with these environments . Several species of economic (e.g., bullfrogs, Mazzoni et al 2009 ;grouper, Qin et al 2001 ) and conservation concern (e.g., pallid sturgeon, Waltzek et al 2014 ; Chinese giant salamander, Geng et al 2010 ;Cunningham et al 2015 ) have experienced catastrophic losses in captivity due to ranaviruses. Given this preliminary information on the possible effects of ranaviruses on highly susceptible hosts, we believe it is reasonable to consider this pathogen a serious threat to the biodiversity of ectothermic vertebrate species.…”