The Adanson’s Terrapin, Pelusios adansonii (Schweigger 1812), is a moderate sized freshwater turtle. This species was described by Schweigger (1812) two centuries ago from a carapace collected in Senegal in 1750 by Michel Adanson, the famous French naturalist. Adanson’s terrapin belongs to the family Pelomedusidae (African side necks) and to the suborder Pleurodira. The ecology of this species is still poorly known. P. adansonii inhabits very dry regions and is only found in the majors lakes and swamps where the water is quiet, shallow, and warm. We recorded its presence in shallow lakes in Senegal (Lac de Guiers) with the water temperatures around 35C to 40C. During the dry season (November through June) it buries itself in mud. The species is predominantly carnivorous, feeding on invertebrates, comprised mainly of mollusks, and smalls vertebrates, including fish and amphibians. P. adansonii is only active during the night and sunset.
The Adanson’s Terrapin carapace length (CL) for specimens from Senegal typically reaches 220 (maximum CL 238 mm) in females and 200 mm in males, with maximum weights of 1620 g for females and 650 g for males. The typical and maximum lengths are variable depending on the locations where they are found. For example, until recently the largest known specimens of P. adansonii were from Sudan at only 185 mm CL, and average length of adults along the range of the species was closer to 150-160 mm CL. The outline of the shell is oval-shaped. The carapace color overall is black, and is typically ornate with numerous radiating small dots or dashes, dark brown to blackish. The plastron is almost entirely or completely bright yellow. Soft parts are grayish to yellowish, the upper and side parts of the head are dark brown with a narrow pattern of dark yellow vermiculation.
This species only exists in the wild in Senegal at Lac de Guiers, and it is on the list of animals fully protected by Senegalese Law 86-844 in the code for the protection of nature and hunting. However, bycatch and bush meat consumption by the local population and migrant fishermen from Mali have only increased the pressure on the species which has seen its numbers shrink quickly and disturbingly in the wild. Since 2002, a community-based conservation project at Tocc-Tocc Wetlands Community Reserve, in the Lac de Guiers area, was initiated by ACI with support of the National Parks of Senegal, Turtle Survival Alliance, Nature Tropicale Senegal (member of IUCN), and British Chelonia Group. Tocc-Tocc Reserve, created to protect key foraging and nesting habitats for Adanson’s terrapin and other wildlife, has now adopted rules that have been accepted by all (including local fishermen, farmers, and cattle ranchers). The major objective of this project is to establish a wildlife refuge to protect a major nesting and feeding habitat of this turtle, as well as African manatees and migratory birds, to raise awareness among fishermen, and help locals to get alternative sources of livelihoods to reduce poverty. The first activity was to gradually reduce and end (after 8 years of implementation), turtle consumption in five villages, and to protect the critical habitat of the species with the collaboration of locals. At Tocc-Tocc Reserve 675 acres of key Pelusios adansonii habitat is protected. Finally, after ten years of efforts to engage the local people in conservation activities, the five largest villages in the local community have reached a collective agreement prohibiting the consumption of turtles. Through our efforts, recent local consumption has almost reached zero. The communities formally pledged to enforce reserve conservation rules at a large meeting held on July 2. 2012. Also present at the meeting were local government officials and representatives from Senegal’s National Parks Service and Water and Forestry Department.
A local team of Eco-guards has been hired, trained, and outfitted with surveillance equipment, now allowing them to ensure the implementation of conservation measures. We will need to continue field surveys in Senegal, and if possible expand them to other countries (Mali, Nigeria, and Chad) in the distribution of this species, to gain a better understanding of the global status of its natural range. Pelusios adansonii is not currently listed in the CITES appendices, and after many years of field experience we feel it should be a listed species. In 2014, we were able to successfully breed this species in captivity for the first time, and our head start program was able to release 31 juveniles back in the wild at Tocc-Tocc Reserve. We believe this species still needs strong proactive conservation measures. Pelusios adansonii is no longer targeted by fishermen in Lac de Guiers for food, but are still caught and drowned in their nets, usually at night, and are then roasted and eaten. Freshwater habitat loss associated with climate change may be driving the progressive decline of this vulnerable population. Increasing agriculture and irrigation activities which use precious freshwater resources in these arid regions, means the species could become more vulnerable or threatened. This long term project is a model of how we can protect endangered species and get the strong support of local communities. But the main lesson learned is that changing habits does not happen overnight. The community based conservation approach is time consuming and requires lot of patience and dedication but is ultimately rewarding when conservation goals are reached.