Tag: softshell turtles

Eaten to extinction: breeding programmes begin for endangered turtles in Vietnam

Considered a delicacy in China and Vietnam, the spotted softshell turtle faces threats from overconsumption and habitat loss.

Conservationists have initiated breeding programmes in Vietnam to recover spotted softshell turtle populations threatened by overconsumption and habitat loss.

Based on a literature study, field surveys across Vietnam, and genetic screenings of collected samples, researchers estimated the range and conservation status of Pelodiscus variegatus, the spotted softshell turtle. The data were then used to model the species’ potential range in Vietnam.

Alarmingly, although several protected areas in Vietnam appear to harbour suitable habitats for the species, no populations were identified in any of the sites, indicating it is especially susceptible to extinction.

The research team releasing juvenile turtles into water.
Release of juveile turtles in Vietnaam. Credit: C. T. Pham and T. Ziegler

To recover natural populations of the species, the Institute of Ecology and Biological Resources and Cologne Zoo, Germany, initiated an in-country breeding programme. In late 2023, they released 50 young and healthy turtles to a site with suitable climate and habitat in northern Vietnam.

It is hoped that additional individuals will be reintroduced to protected areas in north-central Vietnam, the sanctuary of spotted softshell turtles, to reverse its declining trend and further contribute to the global Reverse the Red movement, a target best accomplished by applying the IUCN’s One Plan Approach to Conservation.

Softshell turtles of the genus Pelodiscus are broadly distributed from southeastern Siberia through China to Vietnam. However, their range is currently extended to Indonesia, northern Australia, western Europe, North America, Hawaii, and Mauritius as a result of human transportation and breeding activities.

The turtles are considered a delicacy in China and some Southeast Asian countries. In China alone, each year hundreds of million turtles are traded, making them the most widely consumed turtles in the world.

Traditionally, this genus had been considered monotypic with only one recognised species, the Chinese softshell turtle (Pelodiscus sinensis). However, recent research has shown that the genus is much more diverse with at least seven species known to science.

Due to their morphological similarity, widespread farming activities, overharvesting, and their aquatic lifestyle, it is often difficult to study them in their natural habitat to better understand their distribution as well as their population and conservation status.

Like other congeners, the spotted softshell turtle is facing tremendous threats, from habitat loss to overharvesting for food and genetic pollution because the Chinese softshell turtle has been farmed across the country, imperilling the native genetic sources.

As the result, the Turtle Taxonomy Working Group, the global authority on taxonomic and conservation status of turtles worldwide, provisionally classifies the species as Critically Endangered, the highest ranking for taxa most vulnerable to extinction.

Original post:

Le MD, Rödder D, Nguyen TT, The Pham C, Nguyen TQ, Ong AV, McCormack TEM, Nguyen TT, Le MH, Ngo HT, Ziegler T (2024) Climatic niche modelling and genetic analyses highlight conservation priorities for the Spotted Softshell Turtle (Pelodiscus variegatus). Nature Conservation 55: 67-82. https://doi.org/10.3897/natureconservation.55.114746

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Newly discovered turtle species is facing extinction

For decades, it has been assumed that the Chinese Softshell Turtles from East Asia all belonged to one and the same species, Pelodiscus sinensis. Widely distributed all the way from the Russian Far East through the Korean Peninsula to China and Vietnam, the species was said to vary substantially in terms of its looks across localities. However, around the turn of the century, following a series of taxonomic debates, scientists revalidated or discovered a total of three species distinct from the ‘original’.

Recently, a Hungarian-Vietnamese-German team of researchers described a fifth species in the genus. Their discovery is published in the open-access journal ZooKeys.

The new species, which differs both genetically and morphologically from the other four, has well-pronounced dark blotches on the underside of its shell. The markings are also the reason why these turtles are going by the scientific name Pelodiscus variegatus, where “variegatus” translates to “spotted” in Latin.

“This morphological feature, among others, led to the discovery that these animals belong to a hitherto undescribed species,” explains Professor Dr. Uwe Fritz of the Senckenberg Natural History Collections in Dresden.

Unfortunately, the identification of multiple species within what used to be a single one has its potentially ill-fated consequences. While the Chinese Softshell Turtle was once considered widespread and not threatened, each newly discovered species “reduces” the individual population numbers.

“When we look at each species, the distribution range as well as the number of individuals is much smaller than when all were combined. Until now, the newly described Spotted Softshell Turtle was considered part of the Lesser Chinese Softshell Turtle Pelodiscus parviformis, which was discovered by Chinese researchers in 1997. Pelodiscus parviformis was already considered critically endangered. Now that its southern representatives have been assigned to a different species, the Spotted Softshell Turtle, the overall population size of each species is even smaller,” explains Balázs Farkas, the study’s Hungarian lead author.

Because of its restricted range and the levels of exploitation it is subjected to, the conservation status of the new species is proposed to be Critically Endangered, according to the criteria of the IUCN Red List of Threatened Species.

Habitat of the newly discovered softshell turtle, Pelodiscus variegatus. Photo by An Vinh Ong.

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Original source:

Farkas B, Ziegler T, Pham CT, Ong AV, Fritz U (2019) A new species of Pelodiscus from northeastern Indochina (Testudines, Trionychidae). ZooKeys 824: 71-86. https://doi.org/10.3897/zookeys.824.31376