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1.
Ecol Evol ; 14(3): e11031, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38435007

RESUMEN

During the last 40 years, the volumes of African pangolins feeding the illegal wildlife trade have dramatically increased. We conducted a conservation genetics survey of the most traded African species, the white bellied pangolin (WBP; Phataginus tricuspis), across three West African countries including Guinea, Côte d'Ivoire, and Ghana. Our study combining mitochondrial DNA sequencing and microsatellite genotyping is the first to reveal a wide pattern of admixture between two of the six mitochondrial lineages as previously delimited within WBP. We found a signature of isolation by distance but a lack of population genetic structuring, supporting the idea that WBP may have underestimated dispersal abilities. Levels of genetic diversity were low in West African lineages (WAfr and Gha) compared to Central Africa, reinforcing the picture of genetic pauperization shared by West African WBP. We observed a 85%-98% decline in the effective population size of WBP occurring c. 3200 to 400 ya, with current numbers (520-590) at the lower end of the conservative thresholds for minimum viable population size. The microsatellite markers were powerful enough to differentiate between individuals and identify replicated samples, confirming the utility of this approach in tracing the pangolin trade. Genetic diversity estimates confirmed that Yopougon, the main bushmeat market from Abidjan (Côte d'Ivoire), was fed by a large trade network as confirmed by vendors reporting 10 different sources situated 62-459 km away from the market. We conclude that WBP distributed in the Upper Guinean Block should be considered a single management unit of high conservation concern, as impacted by genetic diversity erosion, drastic decline in effective population size, and wide range sourcing for feeding urban bushmeat markets. Given the genetic admixture pattern detected within WBP from West Africa, we advocate for a multi-locus strategy to trace the international trade of the species.


Au cours des 40 dernières années, les volumes de pangolins africains alimentant le commerce illégal d'espèces sauvages ont augmenté de façon spectaculaire. Nous avons mené une étude de génétique de la conservation sur l'espèce africaine la plus braconnée, le pangolin à ventre blanc (PVB; Phataginus tricuspis), à travers trois pays d'Afrique de l'Ouest incluant la Guinée, la Côte d'Ivoire et le Ghana. Notre étude combinant le séquençage de l'ADN mitochondrial et le génotypage par microsatellites est la première à révéler un patron généralisé d'admixture entre deux des six lignées mitochondriales précédemment délimitées au sein du PVB. Nous mettons en évidence une signature d'isolement par la distance mais un manque de structuration génétique des populations, soutenant l'idée que le PVB a des capacités de dispersion jusque­là sous­estimées. Les niveaux de diversité génétique observés dans les lignées d'Afrique de l'Ouest (WAfr et Gha) sont faibles par rapport à ceux observés en Afrique Centrale, confirmant la paupérisation génétique des populations de PVB en Afrique de l'Ouest. Nous avons observé un déclin de 85 à 98% de la taille efficace de la population ouest­africaine entre 3200 et 400 ans, les estimations actuelles (520­590) se situant à l'extrémité inférieure des seuils minimums de viabilité. Les marqueurs microsatellites utilisés sont suffisamment puissants pour différencier les individus et identifier les doublons d'échantillons, confirmant l'utilité de ces marqueurs pour tracer le commerce des pangolins. Nos estimations de diversité génétique ont confirmé que Yopougon, le principal marché de viande de brousse d'Abidjan (Côte d'Ivoire), était alimenté par un vaste réseau commercial, comme le confirment les vendeurs signalant 10 sources différentes situées à 62­459 km du marché. Nous concluons que les PVB présents dans le bloc forestier de Haute Guinée devraient être considérés comme une seule unité de gestion à fort intérêt de conservation, étant soumis à une érosion de sa diversité génétique, un déclin drastique de la taille efficace de sa population et un approvisionnement à grande échelle des marchés urbains de viande de brousse. Compte tenu du schéma d'admixture génétique détecté chez les PVB d'Afrique de l'Ouest, nous préconisons une stratégie multi­locus pour tracer le commerce international de l'espèce.

2.
Biology (Basel) ; 12(8)2023 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-37626941

RESUMEN

Organisms that are similar in size, morphological characteristics, and adaptations, including vertebrates, often coexist by partitioning the available resources (food, space, and time). So, studies of the dynamics of these cases of coexistence are scientifically interesting. Here, we study a coexistence case of two species of freshwater turtles inhabiting the forest waterbodies of West Africa, focusing on the dietary habits of the two species. We found that both turtle species are omnivorous generalists, eating both vegetal and animal matter abundantly. However, there were clear interspecific differences, with the larger of the two species (P. cupulatta) eating more vertebrates (mainly fish but occasionally other vertebrates), whereas P. castaneus consumed more invertebrates. These patterns appeared consistently within the species and across sites, highlighting that the same patterns were likely in other conspecific populations from the Upper Guinean forest streams (Côte d'Ivoire and Liberia). Our study also showed that interspecific competition for food does not occur between these two species; instead, previous studies uncovered that a clear partitioning of the habitat niche occurs. We conclude that the food resource is likely unlimited in the study areas, as it is not the case in more arid environments (since food shortages may occur during the dry season). We anticipate that, within the Pelomedusidae communities throughout Africa, intense competition for food probably occurs in the Sahel and Sudanian vegetation zones, particularly during the dry months, but is unlikely within the Guinea and wet savannah region and even less likely in the Guineo-Congolian rainforest region.

3.
One Health ; 16: 100503, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36875888

RESUMEN

Social media provides a platform for wildlife crime syndicates to access a global consumer-driven market. Whilst studies have uncovered the online trade in wildlife, the availability of wild meat (bushmeat) has not been assessed. To investigate the sale of wild meat online, we analysed 563 posts published between 2018 and 2022 from six West African Facebook pages selected using predetermined search criteria. Across 1511 images and 18 videos, we visually identified 25 bushmeat species-level taxa including mammals (six Rodentia, five Artiodactyla, three Carnivora, two Pholidota, one Primate, two Lagomorpha, one Hyracoidea), birds (three Galliformes) and reptiles (two Squamata), predominately advertised as smoked (63%) or fresh (30%) whole carcasses or portions. Among the species identified, 16% feature a status of concern on the International Union for Conservation of Nature (IUCN) Red List (Near Threatened to Endangered), 16% are listed on the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES; Appendix I and II) and 24% are either fully or partially protected by local legislation. Images were commonly used as propaganda rather than to display inventory, where additional taxa protected from game hunting in West Africa, such as hornbill, were exclusively listed in captions. The advertisement of these protected and vulnerable species on the surface web indicates weak local and international legislative enforcement. Comparatively, when the same search criteria were applied to the deep web browser Tor no results were generated, reinforcing the idea that bushmeat vendors have no need to hide their activities online. Despite local and international trade restrictions, the taxa advertised feature similarities with bushmeat seizures reported in Europe, alluding to the interconnectedness of the trade facilitated by social media. We conclude that enhanced policy enforcement is essential to combat the online sale of bushmeat and mitigate the potential biodiversity and public health impacts.

4.
MethodsX ; 9: 101867, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36249934

RESUMEN

Among non-invasive biological samples, feces offer an important source of DNA and can easily be collected. However, working with fecal DNA from highly vegetarians species such as elephant is more challenging because plant secondary compounds have an inhibitory effect on PCR reactions. Working with forest elephant dung samples, we tested and adapted a protocol of DNA extraction developed on plants based on the Cetyltrimethylammonium bromide (CTAB) protocol. The protocol is relatively simple and yields a high DNA concentration. It is five-time less expensive compared to the methods of Benbouza et al. The extracted DNA is of good quality and easily amplified by PCR. The high-amplification percentage of mitochondrial genes in fecal DNA and subsequent sequencing of PCR products indicate that the proposed optimized method is reliable for molecular analysis of forest elephant dung samples.•Our optimized CTAB protocol has been adjusted by the addition of Sodium Dodecyl Sulfate (SDS) and proteinase K during the lysis phase. The combined effect of these reagents was capable of lysing cell walls and removing proteins efficiently.•Moreover, the prolonged time of incubation (overnight incubation at room temperature followed by 3 hours of incubation in a water bath) enhanced the increase of DNA yield but make the optimized protocol more time-consuming.

5.
BMC Med Genomics ; 15(1): 120, 2022 05 23.
Artículo en Inglés | MEDLINE | ID: mdl-35606796

RESUMEN

BACKGROUND: Sickle cell disease (SCD) is a hemoglobin disorders that concern 300,000 newborns each year around the world. There are hemoglobin haplotypes that affect SCD clinic expression. METHODS: Our goal was to identify the hemoglobin's haplotypes among individuals with mild malaria independently of SCD status in Côte d'Ivoire. To determine these haplotypes, specific restriction enzyme (RE) is used after PCR amplification with each primer. According to the digestion of PCR product by RE, five hemoglobin's haplotypes are found in the world. RESULTS: In Côte d'Ivoire, no study has yet deeply described the distribution of haplotypes. Four different "classical" haplotypes of hemoglobin were detected: Benin (56.5%), Bantou (28.5%), Senegal (4%), Cameroun (1%); and 10% of atypical profiles. Heterozygous haplotype (69%) were more frequent than homozygous haplotype (31%). CONCLUSIONS: In this preliminary study, we note a high prevalence of atypical and heterozygous haplotype. Benin haplotype that is associated with severity of SCD was most predominant in our studied population.


Asunto(s)
Anemia de Células Falciformes , Malaria , Anemia de Células Falciformes/complicaciones , Anemia de Células Falciformes/epidemiología , Anemia de Células Falciformes/genética , Côte d'Ivoire , Haplotipos , Hemoglobina Falciforme/genética , Hemoglobinas , Humanos , Malaria/complicaciones , Malaria/genética
7.
PLoS One ; 15(10): e0232993, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33052917

RESUMEN

In pre-colonial and colonial times Côte d'Ivoire probably hosted one of the largest elephant populations in West Africa, resulting in the country's name Côte d'Ivoire (in English Ivory Coast) by French settlers. Numbers declined and by the early 90s it was estimated that the total number of both savannah and forest elephants had reached 63 to 360 elephants in the entire country. Here we present updated information on the distribution and conservation status of forest elephant in Côte d'Ivoire based on multiple sources-dung counts on line transects, records of human-elephant conflict, media reports, sign and interview surveys-obtained during the period 2011-2017. We used Pearson correlation to determine the correlation between the presence of forest elephant and site variables (size of the forest, percentage of area converted into plantation, size of the forest left, size of human population inside the PA, poaching index, distance to the nearest road, population density in the Department, level of protection of the PA). To examine the effect of ecological traits on elephant extirpation, we used Principal Components Analysis (PCA) to check for multicollinearity among variables. Based on dung count elephant presence was confirmed in only 4 of the 25 protected areas surveyed. PAs with higher level of protection have higher probability to be home of elephant population. The viability of these populations is uncertain, since they have a small size and are isolated. Aggressive conservation actions including law enforcement for the protection of their remaining habitat and ranger patrolling are needed to protect the remaining forest elephant populations.


Asunto(s)
Conservación de los Recursos Naturales/métodos , Elefantes/crecimiento & desarrollo , Animales , Côte d'Ivoire , Extinción Biológica , Humanos , Densidad de Población , Análisis de Componente Principal , Encuestas y Cuestionarios
8.
Folia Primatol (Basel) ; 83(1): 11-23, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22699713

RESUMEN

Côte d'Ivoire holds 18 catarrhine taxa, with 3 endemic to Côte d'Ivoire and neighbouring Ghana. Nine of the taxa occurring in Côte d'Ivoire are listed as threatened at the global level. However, information on their conservation status within the country is available for only a limited number of taxa. In order to assess the current distribution of primates and their conservation status, we conducted foot surveys and interviews in protected forests in the southern part of Côte d'Ivoire. Our data suggest that 22 out of 23 surveyed forests have lost 25-100% of the primate taxa expected to occur in these areas. The only exception is the Taï National Park where all of the expected primate taxa were encountered. Based on our surveys, we propose an updated national list according to the IUCN Red List criteria for all diurnal primate species of Côte d'Ivoire.


Asunto(s)
Cercopithecidae/fisiología , Conservación de los Recursos Naturales , Especies en Peligro de Extinción , Pan troglodytes/fisiología , Animales , Côte d'Ivoire , Dinámica Poblacional
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