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Chaber, A.-L.

Publications and source records attributed to Chaber, A.-L..

4 recordsLinked to original sources

Advancing global DNA-referencing of bushmeat in African tropical forests: a tool for identifying trade hotspots and dynamics in western and central Africa

The bushmeat trade in Africa is a largely unregulated activity that drives the unsustainable exploitation of wild terrestrial vertebrates--an issue often coined the bushmeat crisis. We build on a four-gene mitochondrial DNA-typing approach to develop an unprecedented reference database framework for effectively tracing the bushmeat trade in tropical Africa. Our dataset comprises over 2,500 samples collected over a 13-yr period across 10 African countries and two European airports. Relying on an expert analytical pipeline and [~]8,700 nucleotide sequences, we identified 96% of samples to the species-level. In contrast, we estimated that conventional two-gene approaches would have yielded 18-26% erroneous or inconclusive taxonomic assignments. DNA-typing refined > 50% of field identifications, with refinement reaching 92-95% for highly processed carcasses seized in Europe. Leveraging expanded taxonomic representation, we empirically refined the genetic species thresholds applied to bushmeat and provide a reproducible pipeline for using our expert reference database from NCBI. Overall, we identified 133 species--mostly mammals--with one-third listed as of conservation concern, and uncovered cryptic diversity evidence within several taxa. Our results also demonstrated the value of community ecology indexes for large-scale monitoring of the bushmeat trade. While national markets generally mirrored regional biodiversity patterns across tropical Africa, Benin emerged as a notable outlier and a key wildlife trade hotspot. We advocate for the integration of community ecology frameworks into surveillance efforts to guide more effective, regionally tailored mitigation strategies. Continued, standardized sampling is essential to broaden taxonomic coverage and enhance detection of cryptic biodiversity in genetic bushmeat monitoring.

genetics↗

A wide diversity of viruses detected in African mammals involved in the wild meat supply chain

The processes involved in acquiring, trading, preparing, and consuming wild meat pose significant risks for the emergence of zoonotic infectious diseases. Several major viral outbreaks have been directly linked to the wild meat supply chain, yet our knowledge of the virome in many mammals involved in this chain remains limited and disproportionately focused on certain mammalian taxa and pathogens. This report presents the findings of a metagenomic viral screening of 99 specimens belonging to 27 wild African mammal species and one domesticated species, all traded for their meat. The study focuses on tissue and swab samples collected from various regions in the Democratic Republic of the Congo and in Brussels, Belgium. A total of fifteen virus strains were detected, belonging to the families Arteriviridae, Retroviridae and Sedoreoviridae (primates), Picobirnaviridae (primates and rodents), Picornaviridae (rodents), Hepadnaviridae (hyrax), Orthoherpesviridae (artiodactylid and carnivore) and Spinareoviridae (carnivore). Several strains were detected in mammalian hosts for the first time, expanding their host range and genetic diversity. Of note is the presence of viruses genetically related to recognised zoonotic pathogens, i.e., human picobirnavirus (Orthopicobirnavirus hominis) (primates and rodents), simian foamy viruses (Simiispumavirus) (primates), and rotavirus A (Rotavirus alphagastroenteritidis) (primates). The presence of these viruses in primates is concerning as non-human primates are phylogenetically closely related to humans, which can facilitate interspecies viral transmission. These findings underscore the high diversity of mammalian viruses and the potential risk of human infection through cross-species transmission during the close interactions with wildlife in the wild meat supply chain.

genomics↗

Genetic tracing of the white-bellied pangolins (Phataginus tricuspis) trade in western central Africa

African pangolins are intensively harvested to feed illegal trade networks. We focused on the conservation genetics of the most trafficked African species, the white-bellied pangolin (WBP; Phataginus tricuspis), through the genotyping of 562 individuals from reference populations and urban bushmeat markets in a vibrant trade hub from western Central Africa. Across Cameroon, Equatorial Guinea and northern Gabon, we observed a lack of genetic differentiation and a signature of isolation-by-distance possibly due to unsuspected dispersal capacities involving a Wahlund effect. Despite a higher level of genetic diversity compared to western Africa, we detected a 74-83% decline in the effective population size of WBP during the Middle Holocene. Private allele frequency tracing approach indicated up to 600 km sourcing distance by large urban markets from Cameroon, involving transnational trade activities. The 20 microsatellites markers used in this study provided the necessary power to distinguish among all WBP individuals and should be considered a valuable resource for future forensic applications. Because lineage admixture was detected in the study area, we recommend a multi- locus approach for tracing the WBP trade. The Yaounde market was a major recruiter of genetic diversity in the region, and should receive urgent conservation action to mitigate the pangolin trade.

genetics↗

Is YouTube(R) promoting the exotic pet trade?Analysis of the global public perception of popular YouTube(R) videos featuring threatened exotic animals.

The exploitation of threatened exotic species via social media challenges efforts to regulate the exotic pet trade and consequently threatens species conservation. To investigate how such content is perceived by the global community, sentiment analysis techniques were employed to explore variations in attitudes expressed through text and emoji usage in public comments associated with 346 popular YouTube(R) videos starring exotic wild cats or primates in captive or domestic situations. Although a negative trend in mean text sentiment was observed in 2015 for primates, an otherwise consistent positive mean sentiment text and emoji score through time was revealed in response to both exotic wild cat and primate videos, implying the societal normalisation and acceptance of exotic pets. These findings highlight the urgency for effective YouTube(R) policy changes and content management to promote public education and conservation awareness, whilst extinguishing false legitimisation and potential demand for the exotic pet trade.

scientific communication and education↗