|Scientific Name:||Cyclanorbis senegalensis (Duméril & Bibron, 1835)|
Cryptopus senegalensis Duméril & Bibron, 1835
Cyclanorbis petersii Gray, 1859
Cyclanosteus senegalensis ssp. callosa Gray, 1865
Cyclanosteus senegalensis ssp. equilifera Gray, 1865
Cyclanosteus senegalensis ssp. normalis Gray, 1865
Cycloderma senegalense Duméril, 1861
Tetrathyra baikii Gray, 1865
Tetrathyra vaillantii Rochebrune, 1884
|Taxonomic Source(s):||Fritz, U. and Havas, P. 2007. Checklist of chelonians of the world. Vertebrate Zoology 57(2): 149-368.|
|Red List Category & Criteria:||Vulnerable A2bcd+4bcd ver 3.1|
|Assessor(s):||Diagne, T., Luiselli, L., Trape, J.-F., Rödel, M.-O., Baker, P.J., Chirio, L., Petrozzi, F. & Segniagbeto, G.|
|Reviewer(s):||Rhodin, A.G.J., van Dijk, P.P. & Horne, B.D.|
|Contributor(s):||Akani, G., Eniang, E., Penner, J. & Fritz, U.|
|Facilitator/Compiler(s):||van Dijk, P.P. & Rhodin, A.G.J.|
This is a widespread African species perceived to be declining across much of its range, especially in West Africa. Declines are due to a combination of exploitation for local consumption and fetish purposes plus some international pet trade; with habitat impacts including, in particular, aridification due to climate change and intensive use of water resources for agriculture. It is not thought to be in significant decline in the far eastern part of its range. Overall across the range, population reduction likely exceeds 30% over the past two generations and predicted into one future generation (with an estimated generation time of 15 years), qualifying it for Vulnerable status (VU A2bcd+4bcd). Cyclanorbis senegalensis was last assessed in 1996, as Near Threatened.
|Previously published Red List assessments:|
Cyclanorbis senegalensis ranges through most of the sub-Saharan Sahel-Savannah zone, including southern Senegal, Gambia, Guinea-Bissau, Mali, Burkina Faso, Liberia, Ivory Coast (Côte d'Ivoire), Ghana, Togo, Benin, Niger, Nigeria, Cameroon, Chad, Central African Republic, South Sudan, Sudan, and Ethiopia. It may also occur peripherally in adjacent Guinea, and conceivably in northern Uganda. It has also recently been recorded in Sierra Leone (U. Fritz, unpubl. data). It possibly occurred in southern Mauritania in past times, but has disappeared from northern Senegal and presumably adjacent Mauritania following the construction of the Diama dam. There appear to be three large disjunct populations: one in West Africa from Senegal to western Nigeria; one in central Africa from Lake Tchad to northern Central African Republic; and one in eastern Africa in Sudan and South Sudan extending into western Ethiopia.
Native:Benin; Burkina Faso; Cameroon; Central African Republic; Chad; Côte d'Ivoire; Ethiopia; Gambia; Ghana; Guinea-Bissau; Liberia; Mali; Niger; Nigeria; Senegal; Sierra Leone; South Sudan; Sudan; Togo
|Range Map:||Click here to open the map viewer and explore range.|
Anecdotal information suggests that the species can be abundant in suitable locations, although given the seasonal dynamics of its preferred pond habitat, such observations may be based on occasional aggregations and concentrations of animals from wide areas (overview by Gramentz 2008). It is suspected to have disappeared from many localities within its wide range. In Nigeria, the species is mostly uncommon (although still widespread in the southwest) and with apparently fragmented populations; it occurs with relatively abundant populations only in a few water bodies inside well-preserved Guinea savannah areas (Akani, Luiselli, Eniang, unpubl. data). In Togo, it is not common and is found only in the northern Sudanese savannah region, with a few populations recorded from Kundja Konkomba, Mango, Kara, and Mandouri, and interviews with local people suggests that it should be present also in the Djambé Nature Reserve. Population sizes are declining in Togo (Segniagbeto et al. 2014). There has been a range contraction in Senegal; historically in the north, and continuing in the Senegal river. In the trans-boundary National Park W at the Benin-Niger border area, it remains locally common (Chirio 2009). In Ivory Coast (Comoé National Park) and Bénin (Pendjari National Park) the species has been regularly observed but is rare (Rödel and Grabow 1995; M.-O. Rödel and J. Penner, unpubl. data). The species occurs in the wetlands of South Sudan, where its populations are probably still relatively unaffected, and it has been recorded in the Gambela region of western Ethiopia.
|Current Population Trend:||Decreasing|
|Habitat and Ecology:||Based on available literature, Cyclanorbis senegalensis appears to utilize nearly any freshwater body in its range, but with a strong emphasis on small, seasonal ponds, puddles and marshes with high productivity and amphibian aggregations (overview by Gramentz 2008). In northern Ghana (Mole National Park), the species occurs along the Nyanga River (F. Petrozzi and M. Di Vittorio, unpubl. data), and in central Nigeria (Lokoja) both along the Niger and the Benue Rivers (Luiselli and Akani, unpubl. data). In Ivory Coast (Comoé National Park) and Bénin (Pendjari National Park) adults inhabit predominantly large permanent ponds as well as deeper, relatively calm parts in riverine forests within the savanna zone (but in shaded waters where they can be observed basking); whereas hatchlings and juveniles may be found far from these habitats in temporary savannah waters (Rödel and Grabow 1995). Both adults and hatchlings have been observed to migrate larger distances across land (Rödel and Grabow 1995; M.-O. Rödel and J. Penner, unpubl. data).|
The diet of C. senegalensis is not well known, but amphibians, particularly tadpoles, and fish, are known to be a significant food source, while larger animals appear morphologically adapted for feeding on freshwater clams and snails (Gramentz 2008). Cyclanorbis senegalensis rarely exceeds 35 cm straight carapace length (SCL), at which size it weighs just under 5 kg (Gramentz 2008), but Trape et al. (2012) stated it could reach 60 cm in SCL. Size and age at maturity and longevity appear unrecorded; by analogy with other medium-sized Trionychid species inhabiting seasonal waterbodies, a generation time of 15 years is estimated. Clutch sizes of 6 to 25 eggs have been indicated in the literature. Hatchlings measure less than 45 mm SCL (review by Gramentz 2008).
|Generation Length (years):||15|
|Use and Trade:||
Cyclanorbis senegalensis is widely collected for local subsistence consumption and traded at local markets (summary by Gramentz 2008). It has been observed as traded also for fetish purposes, at least in Togo (Segniagbeto et al. 2013). The species is also traded in the international pet trade, at low to modest numbers.
Whether the widespread collection and subsistence consumption of Cyclanorbis senegalensis translates to significant impacts on local or global populations has not been documented. Being specialized to take advantage of both permanent and seasonal water bodies in a biome where rainfall patterns are shifting as a result of global climate change, this species may be at particular risk, both directly as well as (and predominantly) indirectly, through shifting agricultural and land use patterns and water usage. Alternatively, construction of local ponds and reservoirs may conceivably create new habitat for the species.
Currently Cyclanorbis senegalensis is not protected or regulated under international legislation. In Nigeria it is on the First Schedule of the 2012 Wildlife Act, indicating that international trade in it is absolutely prohibited. Cyclanorbis senegalensis is well represented in protected areas, including Niokola-Koba National Park (Senegal), Pendjari NP (Benin), Comoé NP (Ivory Coast / Côte d'Ivoire), trans-boundary National Park W (Niger, Benin, Burkina Faso), Oti-Keran National Park (Togo), and Mole NP (Ghana), and likely occurs in other protected areas as well, apparently including Gambela NP in Ethiopia. Monitoring and possible regulation of collection, local consumption trade, and the heretofore somewhat limited international trade of this species appears warranted. Surveys of distribution and population status, monitoring of representative populations, and verifying occurrence in secure protected areas would be very helpful. A quantitative analysis of the effects of climate change on this species, direct and indirect, appears necessary.
|Citation:||Diagne, T., Luiselli, L., Trape, J.-F., Rödel, M.-O., Baker, P.J., Chirio, L., Petrozzi, F. & Segniagbeto, G. 2016. Cyclanorbis senegalensis. The IUCN Red List of Threatened Species 2016: e.T6005A96447114.Downloaded on 22 June 2018.|
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