8 research outputs found
Habitat use and nutrition of chimpanzees in an anthropogenic landscape: A case study in Bossou, Guinea, West Africa
Get PDFHuman population increases and an expanding agricultural frontier are driving tropical deforestation. As a result, many primates are increasingly found outside of protected areas in highly-disturbed environments in close proximity to humans. A better understanding of primate species adaptability to human pressures and the ability of anthropogenic landscapes to support viable populations in the long-term is critical for effective conservation efforts. By focusing on the chimpanzee (Pan troglodytes verus) community in the anthropogenic landscape of Bossou, Guinea, West Africa, I aimed to 1) empirically describe the composition and availability of chimpanzee resources across fine spatial scales, 2) examine chimpanzee use and activity budget across available habitat types and in relation to anthropogenic pressures and risks, 3) determine the macronutrient composition of wild and cultivated chimpanzee foods, and 4) investigate chimpanzee macronutrient intake and balancing from wild and cultivated foods.
To examine objective 1, I undertook quadrat vegetation surveys and phenology surveys to spatially and temporally quantify chimpanzee food resources in all available habitat types. Bossou is largely composed of regenerating forest and the scarcity of large fruit bearing trees is offset by a high diversity of wild and cultivated chimpanzee food species. Moraceae (mulberries and figs) is the dominant family, trees of which produce drupaceous fruits favoured by chimpanzees. The oil palm, which provides the chimpanzees with year-round food resources, occurs at high densities throughout Bossou. Mature and secondary forests are the most important habitat types for food species availability. Overall, these results emphasise the importance of examining ecological characteristics of an anthropogenic landscape as each available habitat type is unlikely to be equally important in terms of spatial and temporal availability of resources.
To examine objective 2, I conducted behavioural follows to record chimpanzee activities and habitat use across all forest and highly disturbed habitat types, and foraging locations in non-cultivated habitat in relation to anthropogenic pressures i.e. cultivated fields and roads and paths. Chimpanzees preferentially use forest habitat types for travelling and resting and highly disturbed habitat types for socialising. The availability of wild fruit and crops influences seasonal habitat use for foraging. The chimpanzees rely heavily on a small patch of mature forest, rich in food species and with low human presence, irrespective of season and activity. The chimpanzees avoid foraging in non-cultivated habitat within 200 m of cultivated fields, with no effect of habitat type or season, suggesting an influence of associated risk. Nevertheless, they did not actively avoid foraging close to roads and paths. These results reveal chimpanzee reliance on different habitat types and the influence of human-induced pressures on their activities.
To examine objective 3, I used standard wet chemistry procedures to estimate the macronutrient content of wild and cultivated chimpanzee foods. The composition of wild fruit, leaves and pith are consistent with previous reports for primate diets. Cultivars are generally higher in carbohydrates and lower in fibre than wild foods, while wild foods are higher in protein. Oil palm food parts are rich in energy, carbohydrates, protein, lipids and/or fermentable fibre fractions; adding nutritional support for the importance of oil palms for chimpanzees in anthropogenic landscapes. These results build on current understanding of chimpanzee feeding ecology and nutrition within forest-agricultural mosaics and provide further empirical evidence that cultivars offer primates energetic benefits over most wild plant foods.
To examine objective 4, I used the macronutrient composition of foods and recorded chimpanzee intakes of wild and cultivated foods during focal follows. Diet composition and macronutrient intakes vary little between the sexes; however females have higher total foods (i.e. wild and cultivated combined), digestible fibre (NDF), and protein intakes when controlling for metabolic body mass. There are no differences in wild or cultivated food intake between seasons; however lipid and protein intake from cultivars, and most likely oil palm food parts, is higher during the fruit scarce season. The chimpanzees maintain their proportional intake of protein while allowing carbohydrate and lipid intakes to vary. Furthermore, they were able to achieve a consistent balance of protein to non-protein (carbohydrates, lipids, and NDF) energy across the year. These results suggest the chimpanzees suffer little seasonal constrains in food quality or availability and are able to combine their consumption of available wild and cultivated foods to achieve a balanced diet.
Overall, this thesis provides new insights into the ecology of anthropogenic landscapes, the influence of human pressures on chimpanzee habitat use and behaviours, and the role of cultivars in chimpanzee foraging strategies and in allowing them to meet their nutritional requirements. Such information is important for informing conservation initiatives aimed at balancing the needs of people and chimpanzees that share space and resources within anthropogenic landscapes
Habitat use and nutrition of chimpanzees in an anthropogenic landscape: A case study in Bossou, Guinea, West Africa
Get PDFHuman population increases and an expanding agricultural frontier are driving tropical deforestation. As a result, many primates are increasingly found outside of protected areas in highly-disturbed environments in close proximity to humans. A better understanding of primate species adaptability to human pressures and the ability of anthropogenic landscapes to support viable populations in the long-term is critical for effective conservation efforts. By focusing on the chimpanzee (Pan troglodytes verus) community in the anthropogenic landscape of Bossou, Guinea, West Africa, I aimed to 1) empirically describe the composition and availability of chimpanzee resources across fine spatial scales, 2) examine chimpanzee use and activity budget across available habitat types and in relation to anthropogenic pressures and risks, 3) determine the macronutrient composition of wild and cultivated chimpanzee foods, and 4) investigate chimpanzee macronutrient intake and balancing from wild and cultivated foods.
To examine objective 1, I undertook quadrat vegetation surveys and phenology surveys to spatially and temporally quantify chimpanzee food resources in all available habitat types. Bossou is largely composed of regenerating forest and the scarcity of large fruit bearing trees is offset by a high diversity of wild and cultivated chimpanzee food species. Moraceae (mulberries and figs) is the dominant family, trees of which produce drupaceous fruits favoured by chimpanzees. The oil palm, which provides the chimpanzees with year-round food resources, occurs at high densities throughout Bossou. Mature and secondary forests are the most important habitat types for food species availability. Overall, these results emphasise the importance of examining ecological characteristics of an anthropogenic landscape as each available habitat type is unlikely to be equally important in terms of spatial and temporal availability of resources.
To examine objective 2, I conducted behavioural follows to record chimpanzee activities and habitat use across all forest and highly disturbed habitat types, and foraging locations in non-cultivated habitat in relation to anthropogenic pressures i.e. cultivated fields and roads and paths. Chimpanzees preferentially use forest habitat types for travelling and resting and highly disturbed habitat types for socialising. The availability of wild fruit and crops influences seasonal habitat use for foraging. The chimpanzees rely heavily on a small patch of mature forest, rich in food species and with low human presence, irrespective of season and activity. The chimpanzees avoid foraging in non-cultivated habitat within 200 m of cultivated fields, with no effect of habitat type or season, suggesting an influence of associated risk. Nevertheless, they did not actively avoid foraging close to roads and paths. These results reveal chimpanzee reliance on different habitat types and the influence of human-induced pressures on their activities.
To examine objective 3, I used standard wet chemistry procedures to estimate the macronutrient content of wild and cultivated chimpanzee foods. The composition of wild fruit, leaves and pith are consistent with previous reports for primate diets. Cultivars are generally higher in carbohydrates and lower in fibre than wild foods, while wild foods are higher in protein. Oil palm food parts are rich in energy, carbohydrates, protein, lipids and/or fermentable fibre fractions; adding nutritional support for the importance of oil palms for chimpanzees in anthropogenic landscapes. These results build on current understanding of chimpanzee feeding ecology and nutrition within forest-agricultural mosaics and provide further empirical evidence that cultivars offer primates energetic benefits over most wild plant foods.
To examine objective 4, I used the macronutrient composition of foods and recorded chimpanzee intakes of wild and cultivated foods during focal follows. Diet composition and macronutrient intakes vary little between the sexes; however females have higher total foods (i.e. wild and cultivated combined), digestible fibre (NDF), and protein intakes when controlling for metabolic body mass. There are no differences in wild or cultivated food intake between seasons; however lipid and protein intake from cultivars, and most likely oil palm food parts, is higher during the fruit scarce season. The chimpanzees maintain their proportional intake of protein while allowing carbohydrate and lipid intakes to vary. Furthermore, they were able to achieve a consistent balance of protein to non-protein (carbohydrates, lipids, and NDF) energy across the year. These results suggest the chimpanzees suffer little seasonal constrains in food quality or availability and are able to combine their consumption of available wild and cultivated foods to achieve a balanced diet.
Overall, this thesis provides new insights into the ecology of anthropogenic landscapes, the influence of human pressures on chimpanzee habitat use and behaviours, and the role of cultivars in chimpanzee foraging strategies and in allowing them to meet their nutritional requirements. Such information is important for informing conservation initiatives aimed at balancing the needs of people and chimpanzees that share space and resources within anthropogenic landscapes
Activity and Habitat Use of Chimpanzees (Pan troglodytes verus) in the Anthropogenic Landscape of Bossou, Guinea, West Africa
Get PDFMany primate populations inhabit anthropogenic landscapes. Understanding their long-term ability to persist in such environments and associated real and perceived risks for both primates and people is essential for effective conservation planning. Primates in forest–agricultural mosaics often consume cultivars to supplement their diet, leading to potentially negative encounters with farmers. When crossing roads, primates also face the risk of encounters with people and collision with vehicles. Chimpanzees (Pan troglodytes verus) in Bossou, Guinea, West Africa, face such risks regularly. In this study, we aimed to examine their activity budget across habitat types and the influence of anthropogenic risks associated with cultivated fields, roads, and paths on their foraging behavior in noncultivated habitat. We conducted 6-h morning or afternoon follows daily from April 2012 to March 2013. Chimpanzees preferentially used forest habitat types for traveling and resting and highly disturbed habitat types for socializing. Wild fruit and crop availability influenced seasonal habitat use for foraging. Overall, chimpanzees preferred mature forest for all activities. They showed a significant preference for foraging at >200 m from cultivated fields compared to 0–100 m and 101–200 m, with no effect of habitat type or season, suggesting an influence of associated risk. Nevertheless, the chimpanzees did not actively avoid foraging close to roads and paths. Our study reveals chimpanzee reliance on different habitat types and the influence of human-induced pressures on their activities. Such information is critical for the establishment of effective land use management strategies in anthropogenic landscapes
Positive and negative interactions with humans concurrently affect vervet monkey, Chlorocebus pygerythrus, ranging behavior
Get PDFMany non-human primates adjust their behavior and thrive in human-altered habitats, including towns and cities. Studying anthropogenic influences from an animal’s perspective can increase our understanding of their behavioral flexibility, presenting important information for human-wildlife cohabitation management plans. Currently, research on anthropogenically disturbed wildlife considers either positive or negative aspects of human-wildlife encounters independently, highlighting a need to consider potential interactions between both aspects. Vervet monkeys, Chlorocebus pygerythrus, are a suitable species to address this gap in research as they tolerate urbanization, however, they are understudied in urban landscapes. We conducted this in KwaZulu-Natal, South Africa, where vervet monkeys are commonly found throughout the anthropogenic landscape. Here we determined, from a monkey’s perspective, how the frequency and nature of human-monkey interactions, both positive (food-related) and negative (human-monkey conflict), affected vervet monkey ranging patterns in an urban environment. Over a year, we assessed the movement patterns of three groups of urban vervet monkeys over one year, analyzing both 95% and 50% kernel density estimates of their home ranges alongside daily path lengths and path sinuosities every month using generalized linear mixed models. Overall, we found that human interactions within the urban landscape affected all measures of ranging to some degree. The core home ranges of vervet monkeys increased with a higher rate of positive human encounters and their total home range increased with an interaction of both positive and negative human encounters. Furthermore, vervet monkeys were less likely to respond (i.e. increase daily path length or path sinuosity) to human aggression when food rewards were high, suggesting that effective management should focus on reducing human-food foraging opportunities. Our results highlight the complex interplay between positive and negative aspects of urban living and provide guidance for managers of human-nonhuman primate interactions
Tools to tipple:Ethanol ingestion by wild chimpanzees using leaf-sponges
Get PDFAfrican apes and humans share a genetic mutation that enables them to effectively metabolize ethanol. However, voluntary ethanol consumption in this evolutionary radiation is documented only inmodern humans.Here, we report evidence of the long-term and recurrent ingestion of ethanol from the raffia palm (Raphia hookeri, Arecaceae) by wild chimpanzees (Pan troglodytes verus) at Bossou in Guinea, West Africa, from 1995 to 2012. Chimpanzees at Bossou ingest this alcoholic beverage, often in large quantities, despite an average presence of ethanol of 3.1% alcohol by volume (ABV) and up to 6.9% ABV. Local people tap raffia palms and the sap collects inplastic containers, and chimpanzees use elementary technology—a leafy tool—to obtain this fermenting sap. These data show that ethanol does not act as a deterrent to feeding in this community of wild apes, supporting the idea that the last common ancestor of living African apes and modern humans was not averse to ingesting foods containing ethanol.</p
