Disappearing giants

by ZSL on

By ZSL's Benjamin Tapley, Andrew Cunningham, Samuel Turvey and Shu Chen.

The world’s largest amphibian is the Chinese giant salamander. These impressive animals can grow to more than 1.8 m in length and are representatives of an ancient amphibian lineage that has been around since the time of the dinosaurs.

Ranked on ZSL’s EDGE list, Chinese giant salamanders have been identified as a global priority for conservation - EDGE species are both Evolutionarily Distinct and Globally Endangered, and these ‘giants’ are sadly at risk of extinction.

Once widespread across much of southern and central China, their numbers have plummeted due to habitat loss and overexploitation to supply a rapidly growing farming industry - they are now assessed as Critically Endangered However, little research has been undertaken to understand which of these threats is the primary driver of giant salamander declines.

We trialled and developed a standardised set of techniques with our Chinese collaborators and undertook a study on giant salamanders across their range in what was one of the largest ever wildlife surveys undertaken in China.  Surveys began in 2013 and were completed in 2016. In that time, we interviewed 2,872 people and our teams spent 7.20 cumulative person-weeks of active searching (snorkelling, spotlighting, rock turning) and 7.33 person-years of passive searching (setting baited humane salamander traps). At the 97 sites we surveyed we only detected 24 salamanders. Whilst 85% of the people we interviewed recognised giant salamanders, the mean last sighting date was 19 years earlier. 

conservationists talking in a river
One of the field survey teams collecting water quality data from suitable giant salamander habitat in Shaanxi Province

One of the team interviewing members of the local community © Benjamin Tapley / ZSL
One of the team interviewing members of the local community

During our fieldwork, teams collected a suite of water parameters (temperature, dissolved oxygen, salinity, alkalinity, hardness, flow rate ammonia, nitrite and nitrate) and documented any signs of exploitation at each survey site. These data, in tandem with our interview survey data, allowed us to investigate overexploitation and habitat loss as drivers of the decline of giant salamanders. At nearly 25% of sites, including protected areas, our teams collected direct and indirect evidence of poaching.

A bow hook used to poach giant salamanders found within a protected areas in Guizhou Province
A bow hook used to poach giant salamanders found within a protected areas in Guizhou Province

Wild chinese giant salamander
One of the 24 Chinese giant salamanders encountered during our field surveys

Furthermore, there was no statistically significant difference between water parameters at sites where we did not detect giant salamanders and/or from sites where they had recently disappeared and where giant salamanders were encountered by our teams and/or had been recently seen by local people. Furthermore, many of the sites we surveyed supported a diverse assemblage of other amphibians, including those that are sensitive to pollution and those that require large swathes of intact habitat. These findings led us to conclude that the decline of giant salamanders across China has been primarily driven by overexploitation.

Until relatively recently, the Chinese giant salamander was thought to represent a single species. However, our previously published research demonstrates that that there are at least three distinct species of giant salamander, including the South China giant salamander (Andrias sligoi). This taxonomic split has ramifications for Chinese giant salamander conservation. Both A. sligoi and the species from which it was split (A. davidianus) are likely to have smaller range sizes and therefore be more threatened than was previously thought for giant salamanders in China. Our team has called for the establishment of conservation breeding programmes as a necessary component of the conservation strategy for Chinese giant salamanders. These programmes require a detailed understanding of the natural history and environmental requirements of the target species. The water quality data collected during this survey has already been used successful to manage a group of Chinese giant salamanders in the reptile and amphibian house at ZSL London Zoo and it is our hope that these data can also be used to inform the management of giant salamanders in dedicated conservation breeding facilities in China.

Chinese giant salamander habitat
One of the many sites with suitable habitats where Chinese giant salamanders were not detected

Time is running out for giant salamanders in China. It is vital that stakeholders and decision-makers strengthen both in situ and ex situ conservation actions for giant salamanders if they are not to be lost forever. 


Please help our vital conservation work continue worldwide:

Donate now
 

Select a blog

Careers at ZSL

Our people are our greatest asset and we realise our vision for a world where wildlife thrives through their ideas, skills and passion. An inspired, informed and empowered community of people work, study and volunteer together at ZSL.

ZSL London Zoo

A blog for lovers of ZSL London Zoo, bringing you extraordinary animal facts and exclusive access to the world's oldest scientific zoo.

ZSL Whipsnade Zoo

Do you love wildlife? Discover more about our amazing animals at the UK's biggest zoo!

Conservation

We're working around the world to conserve animals and their habitats, find out more about our latest achievements.

Science

From the field to the lab, catch up with the scientists on the cutting edge of conservation biology at ZSL’s Institute of Zoology.

Education

A day in Discovery and Learning at ZSL is never dull! The team tell us all about the exciting sessions for school children, as well as work further afield.

Artefact of the month

Every month, one of the pieces held in ZSL’s Library and at ZSL Whipsnade Zoo will feature here as Artefact of the Month.

Wild About

Read testimonials from our Members and extracts from ZSL's award winning members' magazine, Wild About.

Chagos Expedition

The Chagos archipelago is a rare haven for marine biodiversity. Hear from the team about our projects to protect the environments in the British Indian Ocean Territory (BIOT).

Asia Conservation Programme

ZSL works across Asia, from the famous national parks of Nepal to marine protected areas in the Philippines. Read the latest updates on our conservation.

Remote Sensing in Ecology and Conservation

An Open Access journal for research at the interface of remote sensing, ecology and conservation.