Can DNA help trace the local trade of pangolins? Conservation genetics of white-bellied pangolins from the Dahomey Gap (West Africa).

BACKGROUND: African pangolins are currently experiencing unprecedented levels of harvesting, feeding both local demands and the illegal international trade. So far, the lack of knowledge on the population genetics of African pangolins has hampered any attempts at assessing their demographic status and tracing their trade at the local scale. We conducted a pioneer study on the genetic tracing of the African pangolin trade in the Dahomey Gap (DG). We sequenced and genotyped 189 white-bellied pangolins from 18 forests and 12 wildlife markets using one mitochondrial fragment and 20 microsatellite loci. RESULTS: Tree-based assignment procedure showed that the pangolin trade is endemic to the DG region, as it was strictly fed by the the Dahomey Gap lineage (DGL). DGL populations were characterized by low levels of genetic diversity, an overall absence of equilibrium, important inbreeding levels, and lack of geographic structure. We identified a 92-98% decline in DGL effective population size 200-500 ya-concomitant with major political transformations along the 'Slave Coast'-leading to contemporaneous estimates being inferior to minimum viable population size (< 500). Genetic tracing suggested that wildlife markets from the DG sourced pangolins through the entire DGL range. Our loci provided the necessary power to distinguish among all the genotyped pangolins, tracing the dispatch of a same individual on the markets and within local communities. We developed an approach combining rarefaction analysis of private allele frequencies with cross-validation of observed data that traced five traded pangolins to their forest origin, c. 200-300 km away from the markets. CONCLUSIONS: Although the genetic toolkit that we designed from traditional markers can prove helpful to trace the illegal trade in pangolins, our tracing ability was limited by the lack of population structure within the DGL. Given the deleterious combination of genetic, demographic, and trade-related factors affecting DGL populations, the conservation status of white-bellied pangolins in the DG should be urgently re-evaluated.

Preservative chemicals as a new health risk related to traditional medicine markets in western Africa.

Health risks associated to the use of tropical wildlife have so far been envisioned through the lens of zoonotic pathogens spread by the bushmeat trade, putting aside the equally vibrant network of traditional medicine markets (TMMs). We collected information on the preservative techniques used for animal body parts from TMMs in Benin through a semi-structured questionnaire addressed to 45 sellers. We show that a recent shift from traditional preservative techniques using harmless treatments towards modern techniques -involving the recurrent use of hazardous chemicals (such as Sniper)- is likely to pose a serious health risk to practitioners and consumers of animal parts from TMMs in Benin. We conclude that the non-regulation of the TMM activities represents a critical risk to both biodiversity conservation and human health in western Africa.

Ethnozoological and commercial drivers of the pangolin trade in Benin.

BACKGROUND: Pangolins are trafficked in unsustainable volumes to feed both local and global trade networks for their meat and the medicinal properties of their derivatives, including scales. We focus on a West African country (Benin) to assess the medicinal and spiritual values of pangolins among different ethnic groups and identify the cohort of buyers involved in the pangolin trade and related economic values along the chain, notably from local diasporas. METHODS: We organised 54 focus groups in villages surrounding occurrence habitats of pangolins across Benin and conducted 35 individual interviews with vendors from five major traditional medicine markets (TMMs). Our questionnaire addressed the different uses of pangolins, the commercial value of pangolin items, the categories of clients and the related selling prices. RESULTS: Pangolin meat was strictly consumed as food. Scales, head, bones, tongue, blood, heart and xiphisternum were the items used by local communities as part of medicinal (65% of the focus groups) and spiritual (37%) practices. Scales were the most frequently used item (use value index = 1.56). A total of 42 medicinal and spiritual uses, covering 15 International Classification of Diseases (ICD) categories, were recorded among ethnic groups. The ICD and spiritual categories-based analyses of similarity showed a partial overlapping of ethnozoological knowledge across Benin, although knowledge was significantly influenced by ethnicity and geographic location. The pricing of pangolins both varied with the category of stakeholders (local communities vs. stakeholders of TMMs) and clients (local and West African clients vs. Chinese community) and the type of items sold. The Chinese community was reported to only buy pangolins alive, and average selling prices were 3-8 times higher than those to West African clients. CONCLUSIONS: Our results confirm that pangolins in Africa are valuable and versatile resources for consumption and medicinal / spiritual practices. The pangolin trade in Benin is based on an endogenous and complex network of actors that now appears influenced by the specific, high-valued demand from the Chinese diaspora. Further investigations are required to assess the growing impact of the Chinese demand on the African wildlife trade.