19 research outputs found
The density and distribution of Ateles geoffroyi in a mosaic landscape at El Zota Biological Field Station, Costa Rica
The genus Ateles is thought to prefer primary forest, as spider monkeys are ripe fruit specialists and generally occupy the upper canopy of tropical forests. However, this generalization could be weakened by new research examining Ateles\u27 use of disturbed and undisturbed habitat. This study measures spider monkey habitat use with density estimates following line transect methodology and encounter frequencies between undisturbed and disturbed habitat in wet and swamp forests. Results indicate no significant difference in habitat use. Preliminary measures of habitat quality show greater overall fruit abundance in primary forest, yet similar Ateles densities suggest factors influencing habitat use in mosaicland is more complex than previous research indicates. A better understanding of spider monkeys in areas of forest disturbance is necessary in order to evaluate their habitat requirements in an increasingly anthropogenic landscape
Gastrointestinal parasites of baboons (Papio papio) in Niokolo-Koba National Park, Senegal
Background: Primates can harbor parasites that could be pathogenic or not for humans and primates themselves. It is necessary to know the parasitological situation of the primates that are under surveillance in the park.Aim: To estimate the prevalence and diversity of gastrointestinal parasites, including zoonotic potential parasites, in baboons in the Niokolo-Koba National Park located in Senegal.Method: Fecal samples (n = 50) from two groups of baboons (A and B) were collected in October 2019. The samples were processed using the flotation technique and the modified Ritchie method. Slides were examined microscopically and the parasite identification was based on morphology, color, and parasite content.Results: A total of seven nematodes (Strongyloides sp., Trichirus sp., Ancylostoma sp., Mammo monogamus, Enterobius sp., Strongyloides stercoralis, Strongyle digestif), one cestode (Bertiella sp.), and one trematode (Fasciolopsis sp.) were identified. The overall prevalence was 78%, while the prevalence of poly-infected samples was 49%. The parasite with zoonotic potential, S. stercoralis, was identified in group B samples. Trichuris sp., which is common and pathogenic to humans and primates, was present with prevalence of 52% and of 32% in groups A and B, respectively.Conclusion: These results suggest that baboons are infested with zoonotic parasites and this situation could expose people working in this park to infection. Contact between humans and these baboons or their feces could expose them to infection with zoonotic parasites
Multilevel analysis of the foraging decisions of western chimpanzees (Pan troglodytes verus) and resource scarcity in a savanna environment at Fongoli, Senegal
Savannas are the hottest, driest, and most open environments occupied by wild chimpanzees (Pan troglodytes). Chimpanzee subsistence strategies are poorly understood in these habitats and, thus, current knowledge primarily resides within the theoretical domain. To address this gap, we empirically test food and habitat selection hypotheses by examining the foraging decisions of chimpanzees in a savanna mosaic environment at Fongoli, Senegal.
The foraging behavior of Fongoli chimpanzees was examined in relation to the macronutrient composition of their foods. As predicted under an energy maximizing strategy, individuals often selected foods that were energy-rich and easy to consume. However, this strategy was a poor predictor for some important foods. Fongoli chimpanzees may select lower quality foods at times to minimize risk of heat stress. At the level of habitat selection, this study asked how the foraging behavior of adult male Fongoli chimpanzees changed with predation risk. We tested for this sensitivity by measuring food intake among relatively risky and safe habitats. Elevated risk of predation did not fully deter adult males from feeding in these habitats, but during such visits they ingested more ripe fruit, an energy-rich food. The third level of analysis addresses landscapes-scale habitat selection processes. Our analysis merges findings on Fongoli chimpanzee food and habitat selection with information on the species' distribution and remotely-sensed land cover to evaluate relationships between landscapes and the species' range. We show that accessibility to drinking water sources, anthropogenic habitat disturbance, and habitat physiognomy are associated with the species' distribution in southeastern Senegal. This study highlights the importance of concurrently examining chimpanzee foraging behavior at several levels to understand interconnected factors that shape their subsistence strategies.</p
The density and distribution of Ateles geoffroyi in a mosaic landscape at El Zota Biological Field Station, Costa Rica
The genus Ateles is thought to prefer primary forest, as spider monkeys are ripe fruit specialists and generally occupy the upper canopy of tropical forests. However, this generalization could be weakened by new research examining Ateles' use of disturbed and undisturbed habitat. This study measures spider monkey habitat use with density estimates following line transect methodology and encounter frequencies between undisturbed and disturbed habitat in wet and swamp forests. Results indicate no significant difference in habitat use. Preliminary measures of habitat quality show greater overall fruit abundance in primary forest, yet similar Ateles densities suggest factors influencing habitat use in mosaicland is more complex than previous research indicates. A better understanding of spider monkeys in areas of forest disturbance is necessary in order to evaluate their habitat requirements in an increasingly anthropogenic landscape.</p
Gastrointestinal parasites of baboons (Papio papio) in Niokolo-Koba National Park, Senegal
Background: Primates can harbour parasites that could be pathogenic or not for humans and primates themselves. It is necessary to know the parasitological situation of the primates that are under surveillance in the park.
Aim: The purpose of this study was to estimate the prevalence and diversity of gastrointestinal parasites, including zoonotic potential parasites, in baboons in the Niokolo-Koba National Park located in Senegal.
Method: Faecal samples (n=50) from two groups of Baboons (A and B) were collected in October 2019. Faecal samples were processed using the flotation technique and the modified Ritchie method. Slides were examined microscopically, and the parasite identification was based on morphology, colour, and parasite content.
Results: A total of seven nematodes (Strongyloides sp., Trichirus sp., Ancylostoma sp., Mammo monogamus, Enterobius sp., Strongyloides stercoralis, Strongle digestif), one cestode (Bertiella sp.) and one trematode (Fasciolopsis sp.) were identified. The overall prevalence was 78% while prevalence of poly-infected samples was 49%. The parasite with zoonotic potential, Strongyloides stercoralis, was identified in group B samples. Trichuris sp. which is common and pathogenic to humans and primates was present with a prevalence of 52% and of 32% in groups A and B, respectively.
Conclusion: These results suggest that baboons are infested with zoonotic parasites and this situation could expose people working in this park to infection. Contact between humans and these baboons or their faeces could expose to infection with zoonotic parasites
Updating Chimpanzee Nesting Data at Mount Assirik (Niokolo Koba National Park, Senegal): Implications for Conservation
The Niokolo Koba National Park (NKNP) is the largest protected area in Senegal and lies at the northern limit of the chimpanzeeâs range in West Africa. Recent information on nesting behavior and factors influencing nesting behavior is available for several sites outside NKNP. However, the information available for NKNP is obsolete. Considering that the adequate management of chimpanzee populations cannot be achieved without strong scientific knowledge, it is essential to update data on chimpanzee, Pan troglodytes verus, nesting behavior in NKNP. For this reason, we surveyed their habitat in Mt. Assirik and recorded 626 chimpanzee nests. The results of the study showed that chimpanzees nest more often in closed-canopy habitats such as gallery forests. The average nest height observed in this study was 8.07 ± 0.36 m, varying between 2 and 20 m, which is well below the heights described in most sites where chimpanzees cohabit with large carnivores. Botanical surveys confirmed that chimpanzees select tree species bearing their nests. In Assirik, 12 of the 37 tree species bearing nests are the most used. The nest decay rate (or the time it takes for a nest to go from the fresh to the skeletal stage) at Assirik averaged 68.8 ± 5.8 days
Contribution Ă lâĂ©tude du rĂ©gime alimentaire du ChimpanzĂ©, Pan troglodytes verus (Schwarz, 1934), Ă Fongoli (KĂ©dougou, SĂ©nĂ©gal)
Le SĂ©nĂ©gal est situĂ© sur la limite nord-ouest de lâaire de rĂ©partition du ChimpanzĂ©. On y trouve la sous-espĂšce de lâAfrique de lâOuest, Pan troglodytes verus, qui est inscrite dans la catĂ©gorie des espĂšces en danger dâextinction sur la liste rouge de lâUnion Mondiale pour la Nature. Elle est la plus menacĂ©e des trois sous-espĂšces de chimpanzĂ©s. Dans cette rĂ©gion, il vit dans des conditions climatiques de savane trĂšs dures en plus de la forte pression anthropique exercĂ©e sur lâhabitat. Le dernier recensement effectuĂ© dans cette rĂ©gion estime une population dâenviron 400 Ă 500 individus. Plusieurs Ă©tudes ont Ă©tĂ© effectuĂ©es sur le chimpanzĂ© dans cette rĂ©gion, mais peu ont portĂ© sur son comportement alimentaire. Sur le site de Fongoli (12°41N, 12°30W), nous avons effectuĂ© un suivi de lâĂ©cologie nutritionnelle de ce primate non humain. Pour cela, nous avons dâabord procĂ©dĂ© par observation directe afin dâĂ©tablir une liste des espĂšces consommĂ©es et la maniĂšre dont elles sont consommĂ©es. Ensuite, ces aliments sont Ă©chantillonnĂ©s pour des analyses au laboratoire. Les analyses nous ont permis de mettre en Ă©vidence et de quantifier les sucres, la matiĂšre grasse, les fibres solubles dans les dĂ©tergents (neutres, acides et lignines) et la prĂ©sence ou non de tannin. Nos rĂ©sultats ont montrĂ© que ces chimpanzĂ©s ont un rĂ©gime principalement frugivore, mais consomment Ă©galement des feuilles, des fleurs, des graines. Ils sont aussi insectivores et consomment des protĂ©ines dâorigine animale. Lâanalyse nutritive des aliments montre un rĂ©gime riche en sucre provenant essentiellement des fruits, une quantitĂ© importante de fibres et de matiĂšre grasse. Cependant, lâaccĂšs Ă cette nourriture devient de plus en plus difficile Ă cause du facteur anthropique. Nous pensons que la maĂźtrise du comportement alimentaire du chimpanzĂ© dans cette rĂ©gion est dâune importance capitale pour une meilleure conservation de cette ressource.Je tiens Ă exprimer toute ma reconnaissance Ă mes encadreurs, les Prs Cheikh Tidiane Ba et Jill D. Pruetz, les Drs Papa Ibnou Ndiaye et Stacy Marie Lindshield. Je les remercie de mâavoir encadrĂ©, orientĂ©, aidĂ© et conseillĂ©. Jâadresse mes sincĂšres remerciements Ă tous les professeurs, intervenants, et Ă toutes les personnes qui par leurs paroles, leurs Ă©crits, leurs conseils et leurs critiques ont guidĂ© mes rĂ©flexions et ont acceptĂ© de me rencontrer et de rĂ©pondre Ă mes questions durant mes recherches. Je remercie vivement la sociĂ©tĂ© Mako Exploration Company pour lâouverture dâesprit de son Administrateur GĂ©nĂ©ral Adjoint M. Fally Diop et du Manager du Bureau Environnement et Social Paul Cannon ainsi que pour leur soutien moral et financier. Jâai aimablement Ă©tĂ© accueilli par cette sociĂ©tĂ©. Jâai aussi pu bĂ©nĂ©ficier de lâaide prĂ©cieuse du Capitaine Cheikh Sylla responsable du bureau Environnement. Je souhaite enfin remercier Dondo Kante, Michel Sadiakho et tout le village de Fongoli qui ont facilitĂ© mon intĂ©gration et mes travaux de terrain
Détermination du statut du Chimpanzé, Pan troglodytes verus, dans une zone non protégée de savane boisée à Bagnomba, Sénégal : Implication pour sa conservation
La limite nord de lâaire de rĂ©partition du chimpanzĂ© se trouve dans la partie sud-Est du SĂ©nĂ©gal, prĂ©cisĂ©ment dans la rĂ©gion de KĂ©dougou caractĂ©risĂ©e par des conditions climatiques inhabituelles pour ce primate. Le dernier recensement du ChimpanzĂ© dans ce pays, effectuĂ© entre 1998 et 1999 avait permis dâestimer lâeffectif de la population Ă environ 500 individus dont 80 % Ă©voluent en dehors des aires protĂ©gĂ©es. Actuellement, la dĂ©gradation des habitats du chimpanzĂ© au SĂ©nĂ©gal ne cesse de progresser en raison dâeffets anthropiques et de changements climatiques. DâoĂč le besoin de rĂ©actualiser les donnĂ©es concernant ce primate au niveau national. Câest ainsi quâun suivi hors parc basĂ© particuliĂšrement sur la collecte dâindices de prĂ©sence du chimpanzĂ© par la mĂ©thode de reconnaissance a Ă©tĂ© proposĂ© par Jill Pruetz au courant de lâannĂ©e 2014. Câest dans ce contexte que nous avons effectuĂ© des prospections dans plusieurs sites dont Bagnomba pour rĂ©pertorier les principaux habitats des chimpanzĂ©s. A Bagnomba (786221 W, 1407110 N), situĂ© sur la partie sud-Est du Parc National du Niokolo Koba en dehors des limites de lâaire protĂ©gĂ©e, nous avons observĂ© un groupe de chimpanzĂ©s constituĂ© de 8 individus, dont 5 adultes et 3 juvĂ©niles, et recensĂ© plus de 400 nids de chimpanzĂ©. Les particularitĂ©s Ă©cologiques des habitats du chimpanzĂ© dans cette zone (relief, vĂ©gĂ©tation, disponibilitĂ© dâaliments, entre autres) associĂ©es Ă leur caractĂšre sacrĂ© par les populations locales constituent des atouts qui favoriseraient la conservation des chimpanzĂ©s dans cette zone si des mesures idoines de protection Ă©taient prises. Actuellement, un suivi rapprochĂ© de la population de chimpanzĂ© Ă Bagnomba dont le principal objectif est de dĂ©terminer la structure des groupes, le comportement et les couloirs de migration entre les habitats. Nous avons par ailleurs rĂ©pertoriĂ© des facteurs anthropiques tels que le dĂ©boisement et lâorpaillage qui constituent des menaces rĂ©elles pour la conservation du chimpanzĂ© dans cette localitĂ©. Pour cette raison, nous pensons que lâacquisition de donnĂ©es scientifiques fiables aidera les dĂ©cideurs Ă prendre les dispositions nĂ©cessaires pour garantir la survie de ce primate non humain dans cette rĂ©gion.Nous tenons Ă remercier vivement les personnes et institutions sans qui ce travail ne pourrait aboutir. Il sâagit entre autres de USFWS, African Wildlife Foundation, la direction des Eaux et ForĂȘts et Chasse et de la Conservation des Sols, la Direction des Parcs Nationaux, les populations locales, les agents du projet Fongoli Savana Chimpanzees et lâInstitut Jane Goodall Espagne basĂ© au SĂ©nĂ©gal