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David P Watts - One of the best experts on this subject based on the ideXlab platform.
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RESEARCH ARTICLE Chimpanzee‐Red Colobus Encounter Rates Show a Red Colobus Population Decline Associated With Predation by Chimpanzees at Ngogo
2015Co-Authors: David P Watts, J. AmslerAbstract:Chimpanzees (Pan troglodytes) hunt various primates, but concentrate on red colobus monkeys (Piliocolobus spp.) wherever the two species are sympatric. The extraordinarily large Ngogo Chimpanzee community in Kibale National Park, Uganda, preys heavily on the local population of red colobus (P. tephrosceles). Census data showed a steep decline in this population in the center of the Chimpanzees’ home range between 1975 and 2007 [Lwanga et al., 2011; Teelen, 2007b]. Given no obvious change in food availability, predation by Chimpanzees was the most likely cause [ibid.; Teelen, 2008]. However, census data from other parts of the home range raised the possibility that the decline was restricted to this central area [Teelen, 2007a] We present data from 1998 to 2012 on the rate of encounters between Chimpanzees and red colobus that provide a Chimpanzee‐centered estimate of red colobus density, thus of predation opportunities, throughout the home range. These corroborate census data by showing a long‐term decline in encounters near the center. They also show that encounters become relativelymore common at increasing distances from the center, but encounter rates have decreased even in peripheral areas and, by implication, the red colobus population has declined throughout the study area. These data corroborate Teelen’s [2008] conclusion that Chimpanzee predation on red colobus during the 1990s and early 2000s was unsustainable. Hunting rates and prey offtake rates have also declined markedly; whether this will allow the red colobus population to recover is unknown. In contrast, rates at which Chimpanzees encountered redtail monkeys (Cercopithecus ascanius) and grey‐cheeked mangabeys (Lophocebus albigena) did not decrease. Neither did they increase, however, contrary to long‐term census data from the center of the study area [Lwanga et al., 2011]. Am. J. Primatol. 75:927–937
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Chimpanzee-red colobus encounter rates show a red colobus population decline associated with predation by Chimpanzees at Ngogo.
2013Co-Authors: David P Watts, Sylvia J. AmslerAbstract:Chimpanzees (Pan troglodytes) hunt various primates, but concentrate on red colobus monkeys (Piliocolobus spp.) wherever the two species are sympatric. The extraordinarily large Ngogo Chimpanzee community in Kibale National Park, Uganda, preys heavily on the local population of red colobus (P. tephrosceles). Census data showed a steep decline in this population in the center of the Chimpanzees' home range between 1975 and 2007 [Lwanga et al., 2011; Teelen, 2007b]. Given no obvious change in food availability, predation by Chimpanzees was the most likely cause [ibid.; Teelen, 2008]. However, census data from other parts of the home range raised the possibility that the decline was restricted to this central area [Teelen, 2007a] We present data from 1998 to 2012 on the rate of encounters between Chimpanzees and red colobus that provide a Chimpanzee-centered estimate of red colobus density, thus of predation opportunities, throughout the home range. These corroborate census data by showing a long-term decline in encounters near the center. They also show that encounters become relatively more common at increasing distances from the center, but encounter rates have decreased even in peripheral areas and, by implication, the red colobus population has declined throughout the study area. These data corroborate Teelen's [2008] conclusion that Chimpanzee predation on red colobus during the 1990s and early 2000s was unsustainable. Hunting rates and prey offtake rates have also declined markedly; whether this will allow the red colobus population to recover is unknown. In contrast, rates at which Chimpanzees encountered redtail monkeys (Cercopithecus ascanius) and grey-cheeked mangabeys (Lophocebus albigena) did not decrease. Neither did they increase, however, contrary to long-term census data from the center of the study area [Lwanga et al., 2011].
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diet of Chimpanzees pan troglodytes schweinfurthii at ngogo kibale national park uganda 1 diet composition and diversity
2012Co-Authors: David P Watts, Kevin B Potts, Jeremiah S Lwanga, John C MitaniAbstract:Chimpanzees (Pan troglodytes) are ecologically flexible omnivores with broad diets comprising many plant and animal foods, although they mostly eat fruit (including figs). Like other ecologically flexible nonhuman primates (e.g., baboons, Papio spp.) with broad diets, their diets vary across habitats. Much data on diets come from short studies that may not capture the range of variation, however, and data are scant on variation within habitats and populations. We present data on diet composition and diversity for Chimpanzees at Ngogo, in Kibale National Park, Uganda, collected over a 15-year period, with a focus on the plant components of the diet. We compare Ngogo data to those on Chimpanzees at the nearby Kibale site of Kanyawara, on other Chimpanzee populations, and on some other frugivorous-omnivorous primates. Results support the argument that Chimpanzees are ripe fruit specialists: Ngogo Chimpanzees ate a broad, mostly fruit-based diet, feeding time devoted to fruit varied positively with fruit availability, and diet diversity varied inversely with fruit availability. Comparison of Ngogo and Kanyawara shows much similarity, but also pronounced within-population dietary variation. Chimpanzees fed much more on leaves, and much less on pith and stems, at Ngogo. Figs accounted for somewhat less feeding time at Ngogo, but those of Ficus mucuso were quantitatively the most important food. This species is essentially absent at Kanayawara; its abundance and high productivity at Ngogo, along with much higher abundance of several other important food species, help explain why Chimpanzee community size and population density are over three times higher at Ngogo. High inter-annual variation at Ngogo highlights the value of long-term data for documenting the extent of ecological variation among Chimpanzee populations and understanding how such variation might affect population biology and social dynamics.
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diet of Chimpanzees pan troglodytes schweinfurthii at ngogo kibale national park uganda 1 diet composition and diversity
2012Co-Authors: David P Watts, Kevin B Potts, Jeremiah S Lwanga, John C MitaniAbstract:Chimpanzees (Pan troglodytes) are ecologically flexible omnivores with broad diets comprising many plant and animal foods, although they mostly eat fruit (including figs). Like other ecologically flexible nonhuman primates (e.g., baboons, Papio spp.) with broad diets, their diets vary across habitats. Much data on diets come from short studies that may not capture the range of variation, however, and data are scant on variation within habitats and populations. We present data on diet composition and diversity for Chimpanzees at Ngogo, in Kibale National Park, Uganda, collected over a 15-year period, with a focus on the plant components of the diet. We compare Ngogo data to those on Chimpanzees at the nearby Kibale site of Kanyawara, on other Chimpanzee populations, and on some other frugivorous–omnivorous primates. Results support the argument that Chimpanzees are ripe fruit specialists: Ngogo Chimpanzees ate a broad, mostly fruit-based diet, feeding time devoted to fruit varied positively with fruit availability, and diet diversity varied inversely with fruit availability. Comparison of Ngogo and Kanyawara shows much similarity, but also pronounced within-population dietary variation. Chimpanzees fed much more on leaves, and much less on pith and stems, at Ngogo. Figs accounted for somewhat less feeding time at Ngogo, but those of Ficus mucuso were quantitatively the most important food. This species is essentially absent at Kanayawara; its abundance and high productivity at Ngogo, along with much higher abundance of several other important food species, help explain why Chimpanzee community size and population density are over three times higher at Ngogo. High inter-annual variation at Ngogo highlights the value of long-term data for documenting the extent of ecological variation among Chimpanzee populations and understanding how such variation might affect population biology and social dynamics. Am. J. Primatol. 73:1–16, 2011. © 2011 Wiley Periodicals, Inc.
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long term research on Chimpanzee behavioral ecology in kibale national park uganda
2012Co-Authors: David P WattsAbstract:Long-term data are crucial for addressing questions about the behavior and ecology of Chimpanzees because of their slow life histories. Despite the long history of field research on Chimpanzees, the number of sites that have provided long-term data on multiple communities in the same population is still small. Long-term data on two habituated Chimpanzee communities in Kibale National Park, Uganda, have provided important insights into variation in Chimpanzee behavioral ecology and life-history strategies. Long-term data on diet, phenology, and forest composition indicate that Ngogo is better habitat for Chimpanzees; this helps explain why Chimpanzee population density is three times higher there than at Kanyawara, why the Ngogo community is three times as large as that at Kanyawara, and why female gregariousness is higher at Ngogo. Both sites have provided important data on sex differences in gregariousness and in space use, on long-term social bonds, on hunting, on intergroup aggression, and on other important topics in behavioral ecology. The large size of the Ngogo community offers valuable insights into demographic influences on behavior and on male reproductive success and into Chimpanzee-red colobus predator–prey dynamics. In this chapter, I summarize some of the major findings of this research and compare Kibale data to those from other long-term Chimpanzee research sites.
Tetsuro Matsuzawa - One of the best experts on this subject based on the ideXlab platform.
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nut cracking tools used by captive Chimpanzees pan troglodytes and their comparison with early stone age percussive artefacts from olduvai gorge
2016Co-Authors: Adrian Arroyo, Tetsuro Matsuzawa, Satoshi Hirata, Ignacio De La TorreAbstract:We present the results of a series of experiments at the Kumamoto Sanctuary in Japan, in which captive Chimpanzees (Pan troglodytes) performed several nut cracking sessions using raw materials from Olduvai Gorge, Tanzania. We examined captive Chimpanzee pounding tools using a combination of technological analysis, use-wear distribution, and micro-wear analysis. Our results show specific patterns of use-wear distribution across the active surfaces of pounding tools, which reveal some similarities with traces on archaeological percussive objects from the Early Stone Age, and are consistent with traces on other experimental pounding tools used by modern humans. The approach used in this study may help to stablish a framework with which to interpret archaeological assemblages and improve understanding of use-wear formation processes on pounding tools used by Chimpanzees. This study represents the first direct comparison of Chimpanzee pounding tools and archaeological material, and thus may contribute to a better understanding of hominin percussive activities.
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first gis analysis of modern stone tools used by wild Chimpanzees pan troglodytes verus in bossou guinea west africa
2015Co-Authors: Alfonso Benitocalvo, Tetsuro Matsuzawa, Susana Carvalho, Adrian Arroyo, Ignacio De La TorreAbstract:Stone tool use by wild Chimpanzees of West Africa offers a unique opportunity to explore the evolutionary roots of technology during human evolution. However, detailed analyses of Chimpanzee stone artifacts are still lacking, thus precluding a comparison with the earliest archaeological record. This paper presents the first systematic study of stone tools used by wild Chimpanzees to crack open nuts in Bossou (Guinea-Conakry), and applies pioneering analytical techniques to such artifacts. Automatic morphometric GIS classification enabled to create maps of use wear over the stone tools (anvils, hammers, and hammers/ anvils), which were blind tested with GIS spatial analysis of damage patterns identified visually. Our analysis shows that Chimpanzee stone tool use wear can be systematized and specific damage patterns discerned, allowing to discriminate between active and passive pounders in lithic assemblages. In summary, our results demonstrate the heuristic potential of combined suites of GIS techniques for the analysis of battered artifacts, and have enabled creating a referential framework of analysis in which wild Chimpanzee battered tools can for the first time be directly compared to the early archaeological record.
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the first Chimpanzee sanctuary in japan an attempt to care for the surplus of biomedical research
2011Co-Authors: Naruki Morimura, Genichi Idani, Tetsuro MatsuzawaAbstract:This article specifically examines several aspects of the human–captive Chimpanzee bond and the effort to create the first Chimpanzee sanctuary in Japan. We discuss our ethical responsibility for captive Chimpanzees that have been used in biomedical research. On April 1, 2007, the Chimpanzee Sanctuary Uto (CSU) was established as the first sanctuary for retired laboratory Chimpanzees in Japan. This initiative was the result of the continuous efforts by members of Support for African/Asian Great Apes (SAGA), and the Great Ape Information Network to provide a solution to the large Chimpanzee colony held in biomedical facilities. However, the cessation of invasive biomedical studies using Chimpanzees has created a new set of challenges because Japan lacks registration and laws banning invasive ape experiments and lacks a national policy for the life-long care of retired laboratory Chimpanzees. Therefore, CSU has initiated a relocation program in which 79 retired laboratory Chimpanzees will be sent to domestic zoos and receive life-long care. By the end of 2009, the number of Chimpanzees living at CSU had decreased from 79 to 59 individuals. A nationwide network of care facilities and CSU to provide life-long care of retired laboratory Chimpanzees is growing across Japan. This will result in humane treatment of these research animals. Am. J. Primatol. 73:226–232, 2011. © 2010 Wiley-Liss, Inc.
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chaines operatoires and resource exploitation strategies in Chimpanzee pan troglodytes nut cracking
2008Co-Authors: Susana Carvalho, Claudia Sousa, Eugenia Cunha, Tetsuro MatsuzawaAbstract:We apply archaeological methods to extend our knowledge of Chimpanzee material culture. The chaine operatoire conceptual framework, as introduced by ethnography, established technology as a phased process. Prehistoric archaeology adopted this concept to elucidate technological variability in tool-making procedures, based on knowledge of tool functions or subsistence patterns. We focused on the detection of operational sequences by wild Chimpanzees (Pan troglodytes verus) when nut cracking with lithic implements at the sites of Bossou and Diecke´, Guinea, West Africa. Thus, while it has recently been claimed that Chimpanzees leave behind recognizable assemblages of stone hammers that can be morphologically distinguished from Oldowan hammers, this is the first study to focus specifically on the existence of operational sequences during the utilization of stone tools by wild Chimpanzees. By combining primatological and archaeological methods and examining ecological areas inhabited by different Chimpanzee groups, we sought technological variability and identified variables influencing regional diversity in tool typology and technology. We compared three case studies: (1) Bossouddirect recording of experimental nut-cracking sessions; (2) Bossoud direct and indirect monitoring of nut-cracking sites in the wild; (3) Dieckedindirect monitoring of nut-cracking sites in the wild. Results suggest that Chimpanzees perform sequences of repeated tool transport and nut cracking. Data show discrimination of tool functions based on tool features. We identified the most technologically complex tool for nut cracking, which was composed of four stones. We found regional diversity in Chimpanzee stone assemblages. Raw-material type and tool mobility constrain technological development in human and nonhuman primates. Spatial analysis of tool distribution indicates a pattern of resource-exploitation strategy, revealing affinities with Oldowan. 2008 Elsevier Ltd. All rights reserved.
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chaines operatoires and resource exploitation strategies in Chimpanzee pan troglodytes nut cracking
2008Co-Authors: Susana Carvalho, Claudia Sousa, Eugenia Cunha, Tetsuro MatsuzawaAbstract:We apply archaeological methods to extend our knowledge of Chimpanzee material culture. The chaine operatoire conceptual framework, as introduced by ethnography, established technology as a phased process. Prehistoric archaeology adopted this concept to elucidate technological variability in tool-making procedures, based on knowledge of tool functions or subsistence patterns. We focused on the detection of operational sequences by wild Chimpanzees (Pan troglodytes verus) when nut cracking with lithic implements at the sites of Bossou and Diecke´, Guinea, West Africa. Thus, while it has recently been claimed that Chimpanzees leave behind recognizable assemblages of stone hammers that can be morphologically distinguished from Oldowan hammers, this is the first study to focus specifically on the existence of operational sequences during the utilization of stone tools by wild Chimpanzees. By combining primatological and archaeological methods and examining ecological areas inhabited by different Chimpanzee groups, we sought technological variability and identified variables influencing regional diversity in tool typology and technology. We compared three case studies: (1) Bossouddirect recording of experimental nut-cracking sessions; (2) Bossoud direct and indirect monitoring of nut-cracking sites in the wild; (3) Dieckedindirect monitoring of nut-cracking sites in the wild. Results suggest that Chimpanzees perform sequences of repeated tool transport and nut cracking. Data show discrimination of tool functions based on tool features. We identified the most technologically complex tool for nut cracking, which was composed of four stones. We found regional diversity in Chimpanzee stone assemblages. Raw-material type and tool mobility constrain technological development in human and nonhuman primates. Spatial analysis of tool distribution indicates a pattern of resource-exploitation strategy, revealing affinities with Oldowan. 2008 Elsevier Ltd. All rights reserved.
Richard W. Wrangham - One of the best experts on this subject based on the ideXlab platform.
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lethal respiratory disease associated with human rhinovirus c in wild Chimpanzees uganda 2013
2018Co-Authors: Erik J Scully, Richard W. Wrangham, Martin N Muller, Sarmi Basnet, Emily Otali, David Hyeroba, Kristine Grindle, T E Pappas, Melissa Emery Thompson, Zarin P MachandaAbstract:We describe a lethal respiratory outbreak among wild Chimpanzees in Uganda in 2013 for which molecular and epidemiologic analyses implicate human rhinovirus C as the cause. Postmortem samples from an infant Chimpanzee yielded near-complete genome sequences throughout the respiratory tract; other pathogens were absent. Epidemiologic modeling estimated the basic reproductive number (R0) for the epidemic as 1.83, consistent with the common cold in humans. Genotyping of 41 Chimpanzees and examination of 24 published Chimpanzee genomes from subspecies across Africa showed universal homozygosity for the cadherin-related family member 3 CDHR3-Y529 allele, which increases risk for rhinovirus C infection and asthma in human children. These results indicate that Chimpanzees exhibit a species-wide genetic susceptibility to rhinovirus C and that this virus, heretofore considered a uniquely human pathogen, can cross primate species barriers and threatens wild apes. We advocate engineering interventions and prevention strategies for rhinovirus infections for both humans and wild apes.
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first molar eruption weaning and life history in living wild Chimpanzees
2013Co-Authors: Tanya M Smith, Zarin P Machanda, Andrew B Bernard, Ronan M Donovan, Amanda M Papakyrikos, Martin N Muller, Richard W. WranghamAbstract:Understanding dental development in Chimpanzees, our closest living relatives, is of fundamental importance for reconstructing the evolution of human development. Most early hominin species are believed to show rapid ape-like patterns of development, implying that a prolonged modern human childhood evolved quite recently. However, Chimpanzee developmental standards are uncertain because they have never been based on living wild individuals. Furthermore, although it is well established that first molar tooth emergence (movement into the mouth) is correlated with the scheduling of growth and reproduction across primates broadly, its precise relation to solid food consumption, nursing behavior, or maternal life history is unknown. To address these concerns we conducted a photographic study of subadult Chimpanzees (Pan troglodytes schweinfurthii) in Kanyawara, Kibale National Park, Uganda. Five healthy infants emerged their lower first molars (M1s) by or before 3.3 y of age, nearly identical to captive Chimpanzee mean ages (∼3.2 y, n = 53). First molar emergence in these Chimpanzees does not directly or consistently predict the introduction of solid foods, resumption of maternal estrous cycling, cessation of nursing, or maternal interbirth intervals. Kanyawara Chimpanzees showed adult patterns of solid food consumption by the time M1 reached functional occlusion, spent a greater amount of time on the nipple while M1 was erupting than in the preceding year, and continued to suckle during the following year. Estimates of M1 emergence age in australopiths are remarkably similar to the Kanyawara Chimpanzees, and recent reconstructions of their life histories should be reconsidered in light of these findings.
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Comparative Feeding Ecology of Two Communities of Chimpanzees (Pan troglodytes) in Kibale National Park, Uganda
2011Co-Authors: Kevin B Potts, David P Watts, Richard W. WranghamAbstract:Several recent studies have documented considerable intraspecific and intrapopulation ecological variation in primates. However, we generally lack an understanding of how such variability may be linked to concomitant demographic variation among groups or populations of the same species, particularly in regard to large-bodied and wide-ranging species with high ecological flexibility, such as Chimpanzees ( Pan troglodytes ). We compared the feeding ecology of Chimpanzees inhabiting 2 sites in Kibale National Park, Uganda that differ 3-fold in Chimpanzee density and support notably different plant communities. Chimpanzees at Ngogo, a site with the largest known Chimpanzee community and unusually high Chimpanzee density, spent a significantly lower percentage of time resting (and pregnant and lactating females spent more time feeding), incorporated higher percentages of ripe fruit in their diet, had lower dietary diversity values, and had shorter and less variable average patch residency times than did their counterparts at the nearby Kanyawara site, which supports a relatively low density of Chimpanzees. In addition, feeding party size was significantly and positively related to feeding patch size at Ngogo, but not at Kanyawara. Together these findings aid in explaining the noted disparity in Chimpanzee community size and density between Ngogo and Kanyawara by suggesting that the diet of Ngogo Chimpanzees is of higher overall quality than that of Kanyawara Chimpanzees. They also highlight the potentially profound influence of even small-scale habitat heterogeneity on the ecology of primates. Researchers must take such influences into account when attempting to draw conclusions about species- or population-level characteristics.
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skeletal pathology in pan troglodytes schweinfurthii in kibale national park uganda
2008Co-Authors: Melinda L Carter, Richard W. Wrangham, Herman Pontzer, Julian Kerbis C PeterhansAbstract:The ecological pressures shaping Chimpanzee anatomy and behavior are the subject of much discussion in primatology and paleoanthropology, yet empirical data on fundamental parameters including body size, morbidity, and mortality are rare for wild Chimpanzees. Here, we present skeletal pathology and body size data for 20 (19 crania, 12 postcrania) Chimpanzees (Pan troglodytes schweinfurthii) from Kibale National Park, Uganda. We compare these data with other East African populations, especially Gombe National Park. Estimated body size for Kibale Chimpanzees was similar to other East African populations and significantly larger than Gombe Chimpanzees. The high rates of trauma and other skeletal pathology evident in the Kibale Chimpanzee skeletons were similar to those in the Gombe skeletal sample. Much of the major skeletal trauma in the Kibale skeletons was attributable to falls, although other pathologies were noted as well, including apparent injuries from snares, degenerative arthritis, and minor congenital abnormalities. Am J Phys Anthropol, 2008. © 2007 Wiley-Liss, Inc.
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diversity of items of low nutritional value ingested by Chimpanzees from kanyawara kibale national park uganda an example of the etho ethnology of Chimpanzees
2006Co-Authors: Sabrina Krief, Richard W. Wrangham, Dominique LestelAbstract:EnglishFor more than 30 years, field studies have shown that Chimpanzees ingest items of low nutritional value such as rough leaves, bitter stems and clay, apparently thereby protecting themselves against parasites and modulating their health. The authors describe the diversity and the biological activities of items of low nutritional value used by Kanyawara Chimpanzees in Uganda, according to scientific observations enriched by the viewpoints of local field assistants and a traditional healer. Their perception of Chimpanzees' behaviour and the overlap with human medicinal uses led the authors to explore Chimpanzee behaviour in a comparative cultural perspective. In spite of the rarity of such observations on wild individuals, study of self-medicative practices offers the opportunity to suggest an epistemology of the Chimpanzee so as to better understand the acquisition and transmission of behaviours linked to diseases.FrenchDepuis une trentaine d'annees, des etudes de terrain ont montre que les chimpanze...
Kevin B Potts - One of the best experts on this subject based on the ideXlab platform.
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diet of Chimpanzees pan troglodytes schweinfurthii at ngogo kibale national park uganda 1 diet composition and diversity
2012Co-Authors: David P Watts, Kevin B Potts, Jeremiah S Lwanga, John C MitaniAbstract:Chimpanzees (Pan troglodytes) are ecologically flexible omnivores with broad diets comprising many plant and animal foods, although they mostly eat fruit (including figs). Like other ecologically flexible nonhuman primates (e.g., baboons, Papio spp.) with broad diets, their diets vary across habitats. Much data on diets come from short studies that may not capture the range of variation, however, and data are scant on variation within habitats and populations. We present data on diet composition and diversity for Chimpanzees at Ngogo, in Kibale National Park, Uganda, collected over a 15-year period, with a focus on the plant components of the diet. We compare Ngogo data to those on Chimpanzees at the nearby Kibale site of Kanyawara, on other Chimpanzee populations, and on some other frugivorous-omnivorous primates. Results support the argument that Chimpanzees are ripe fruit specialists: Ngogo Chimpanzees ate a broad, mostly fruit-based diet, feeding time devoted to fruit varied positively with fruit availability, and diet diversity varied inversely with fruit availability. Comparison of Ngogo and Kanyawara shows much similarity, but also pronounced within-population dietary variation. Chimpanzees fed much more on leaves, and much less on pith and stems, at Ngogo. Figs accounted for somewhat less feeding time at Ngogo, but those of Ficus mucuso were quantitatively the most important food. This species is essentially absent at Kanayawara; its abundance and high productivity at Ngogo, along with much higher abundance of several other important food species, help explain why Chimpanzee community size and population density are over three times higher at Ngogo. High inter-annual variation at Ngogo highlights the value of long-term data for documenting the extent of ecological variation among Chimpanzee populations and understanding how such variation might affect population biology and social dynamics.
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diet of Chimpanzees pan troglodytes schweinfurthii at ngogo kibale national park uganda 1 diet composition and diversity
2012Co-Authors: David P Watts, Kevin B Potts, Jeremiah S Lwanga, John C MitaniAbstract:Chimpanzees (Pan troglodytes) are ecologically flexible omnivores with broad diets comprising many plant and animal foods, although they mostly eat fruit (including figs). Like other ecologically flexible nonhuman primates (e.g., baboons, Papio spp.) with broad diets, their diets vary across habitats. Much data on diets come from short studies that may not capture the range of variation, however, and data are scant on variation within habitats and populations. We present data on diet composition and diversity for Chimpanzees at Ngogo, in Kibale National Park, Uganda, collected over a 15-year period, with a focus on the plant components of the diet. We compare Ngogo data to those on Chimpanzees at the nearby Kibale site of Kanyawara, on other Chimpanzee populations, and on some other frugivorous–omnivorous primates. Results support the argument that Chimpanzees are ripe fruit specialists: Ngogo Chimpanzees ate a broad, mostly fruit-based diet, feeding time devoted to fruit varied positively with fruit availability, and diet diversity varied inversely with fruit availability. Comparison of Ngogo and Kanyawara shows much similarity, but also pronounced within-population dietary variation. Chimpanzees fed much more on leaves, and much less on pith and stems, at Ngogo. Figs accounted for somewhat less feeding time at Ngogo, but those of Ficus mucuso were quantitatively the most important food. This species is essentially absent at Kanayawara; its abundance and high productivity at Ngogo, along with much higher abundance of several other important food species, help explain why Chimpanzee community size and population density are over three times higher at Ngogo. High inter-annual variation at Ngogo highlights the value of long-term data for documenting the extent of ecological variation among Chimpanzee populations and understanding how such variation might affect population biology and social dynamics. Am. J. Primatol. 73:1–16, 2011. © 2011 Wiley Periodicals, Inc.
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Comparative Feeding Ecology of Two Communities of Chimpanzees (Pan troglodytes) in Kibale National Park, Uganda
2011Co-Authors: Kevin B Potts, David P Watts, Richard W. WranghamAbstract:Several recent studies have documented considerable intraspecific and intrapopulation ecological variation in primates. However, we generally lack an understanding of how such variability may be linked to concomitant demographic variation among groups or populations of the same species, particularly in regard to large-bodied and wide-ranging species with high ecological flexibility, such as Chimpanzees ( Pan troglodytes ). We compared the feeding ecology of Chimpanzees inhabiting 2 sites in Kibale National Park, Uganda that differ 3-fold in Chimpanzee density and support notably different plant communities. Chimpanzees at Ngogo, a site with the largest known Chimpanzee community and unusually high Chimpanzee density, spent a significantly lower percentage of time resting (and pregnant and lactating females spent more time feeding), incorporated higher percentages of ripe fruit in their diet, had lower dietary diversity values, and had shorter and less variable average patch residency times than did their counterparts at the nearby Kanyawara site, which supports a relatively low density of Chimpanzees. In addition, feeding party size was significantly and positively related to feeding patch size at Ngogo, but not at Kanyawara. Together these findings aid in explaining the noted disparity in Chimpanzee community size and density between Ngogo and Kanyawara by suggesting that the diet of Ngogo Chimpanzees is of higher overall quality than that of Kanyawara Chimpanzees. They also highlight the potentially profound influence of even small-scale habitat heterogeneity on the ecology of primates. Researchers must take such influences into account when attempting to draw conclusions about species- or population-level characteristics.
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the long term impact of timber harvesting on the resource base of Chimpanzees in kibale national park uganda
2011Co-Authors: Kevin B PottsAbstract:Commercial timber harvesting results in the loss of critical habitat for tropical forest fauna, and large-bodied frugivores (including Chimpanzees and most other apes) may experience particularly detrimental effects. Few quantitative data, however, are available to evaluate the long-term impact of harvesting on Chimpanzees and other apes. In particular, few data are available to compare population demographics and/or forest composition before and after timber harvesting at the same site. Utilizing detailed forestry department records of logging operations conducted in the late 1960s, present-day botanical surveys, and long-term data on the feeding ecology of Chimpanzees in Kibale National Park (KNP), Uganda, I examined the impact that logging has had on KNP Chimpanzee communities of known size and demography. Although some important Chimpanzee food resources were harvested in high abundance during commercial logging operations, the overall impact on the most predominant dietary items (those making up roughly 75% of the Chimpanzees’ diet) and on presumably critical subsistence resources was limited. Furthermore, the low density of Chimpanzees inhabiting the logged region of KNP is apparently not attributable to the impact of logging at the site: comparisons of resource densities at this ‘low-Chimpanzee-density’ site with that of an unlogged and ‘high-Chimpanzee-density’ KNP site did not differ when logging concessions at the low-Chimpanzeedensity site were excluded from the analysis. This study suggests that low-intensity logging can be compatible with the conservation of large-bodied frugivores, provided that dietary data are taken into account in forest management planning.
Jill D. Pruetz - One of the best experts on this subject based on the ideXlab platform.
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stable isotope variation in savanna Chimpanzees pan troglodytes verus indicate avoidance of energetic challenges through dietary compensation at the limits of the range
2019Co-Authors: Erin G Wessling, Jill D. Pruetz, Viktoria M Oelze, Henk Eshuis, Hjalmar S KuhlAbstract:OBJECTIVES: Food scarcity is proposed to be a limitation to Chimpanzees at the limits of their range; however, such a constraint has never been investigated in this context. We investigated patterns of δ13 C and δ15 N variation along a latitudinal gradient at the northwestern West African Chimpanzee (Pan troglodytes verus) range limit with the expectation that isotope ratios of Chimpanzees at the range limit will indicate different dietary strategies or higher physiological constraints than Chimpanzees further from the edge. MATERIALS AND METHODS: We measured δ13 C and δ15 N values in hair (n = 81) and plant food (n = 342) samples from five Chimpanzee communities located along a latitudinal gradient in Southeastern Senegal. RESULTS: We found clear grouping patterns in hair δ13 C and δ15 N in the four southern sites compared to the northernmost site. Environmental baseline samples collected from these sites revealed overall higher plant δ15 N values at the northernmost site, but similar δ13 C values across sites. By accounting for environmental baseline, Δ13 C and Δ15 N values were clustered for all five sites relative to total Pan variation, but indicated a 13 C-enriched diet at the range limit. DISCUSSION: Clustering in Δ13 C and Δ15 N values supports that strategic shifting between preferred and fallback foods is a likely ubiquitous but necessary strategy employed by these Chimpanzees to cope with their environment, potentially allowing Chimpanzees at their limits to avoid periods of starvation. These results also underline the necessity of accounting for local isotopic baseline differences during inter-site comparison.
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informing protection efforts for critically endangered Chimpanzees pan troglodytes verus and sympatric mammals amidst rapid growth of extractive industries in senegal
2019Co-Authors: Stacy M. Lindshield, Stephanie L Bogart, Malle Gueye, P Ndiaye, Jill D. PruetzAbstract:Updated information on Critically Endangered western Chimpanzees (Pan troglodytes verus) in Senegal is urgently needed, given that gold mining is rapidly transforming landscapes and livelihoods. Specifically, biodiversity assessments will better elucidate the Chimpanzee extinction risk here and yield baselines for monitoring. We compared mammal species richness between Fongoli (unprotected) and Assirik in Niokolo-Koba National Park to assess the efficacy of the only nationally protected area where Chimpanzees range in this country. The primary habitat difference between these sites was the degree of human activity. Although Assirik and Fongoli had similar mammal assemblages and were equivalent in primate species richness, the protected area was higher in species richness overall, particularly for ungulates and carnivores. The protected status and management plan of Niokolo-Koba almost certainly resulted in fewer mammal extinctions. In unprotected areas, the flexible behavioural responses of Chimpanzees to human-driven landscape dynamics is likely essential to their long-term survival. Furthermore, the near absence of Chimpanzee killings in this country greatly facilitates conservation efforts. Given that mineral extraction is a key development strategy in Senegal, we encourage primatologists to collaborate with mining stakeholders to ensure that sustainability programming includes contributions from experts in savannah Chimpanzee behavior and ecology.
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Nest-Building Behaviour by Chimpanzees (Pan troglodytes verus) in the Non-Protected Area of Diaguiri (Kedougou, Senegal): Implications for Conservation.
2018Co-Authors: Papa Ibnou Ndiaye, Landing Badji, Stacy M. Lindshield, Jill D. PruetzAbstract:Diaguiri is a non-protected area situated in south-eastern Senegal. Chimpanzees (Pan troglodytes verus) have been living here since 1999 but information on the characteristics of their nest sites have been lacking until now. Furthermore, we implemented nest survey methods recently standardised to arid landscapes during a national Chimpanzee survey. Variations in nest decay rates are poorly understood in savanna-woodland mosaic habitats. This study aims to describe in Diaguiri: (1) the distribution of Chimpanzee nests and the location of their core sleeping area, (2) the tree species used for nest building, (3) the association between nests and nesting tree heights, and (4) differences in nest decay rates between habitats. We surveyed 43 km of Chimpanzee nesting habitats and recorded 871 nests in gallery forest and woodland habitats between March 2015 and June 2016. Diaguiri Chimpanzees used at least 17 tree species for nest building, and 58.8% of nests were in only 3 tree species: Pterocarpus erinaceus, Anogeissus leiocarpus and Diospyros mespiliformis. Nest decay rate was faster in gallery forests than in woodlands. These data are of great value for understanding habitat use by a Critically Endangered subspecies of savanna Chimpanzee, for population density estimates of the species and for conservation programmes in this region and in savanna biomes.
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seasonal variation in physiology challenges the notion of Chimpanzees pan troglodytes verus as a forest adapted species
2018Co-Authors: Erin G Wessling, Jill D. Pruetz, Roman M Wittig, Tobias Deschner, Roger Mundry, Hjalmar S KuhlAbstract:Savanna-mosaic habitats are thought to represent exceptional circumstances for Chimpanzees (Pan troglodytes), and owing to the virtues of their habitat as well as peripheral biogeographic location, they are often regarded as marginal to the Chimpanzee ecological niche. If these habitats are marginal, then we should expect that Chimpanzees living in these habitats demonstrate physiological consequences of the extremity of this environment. We therefore compared seasonal variation in physiological responses to climatic and ecological factors in Chimpanzees inhabiting Fongoli, a savanna-mosaic habitat at the margins of the Chimpanzee range with Chimpanzees from Tai National Park, a lowland rainforest centrally located within the West African Chimpanzee subspecies (P. troglodytes verus) range. We accomplished this using urinary biomarkers of hydration (creatinine), energetic status (c-peptide), and stress (cortisol) collected simultaneously from research stations at each location. We found that Fongoli was both more extreme and seasonal in climatic measures like temperature and rainfall, although food availability was more variable at Tai than at Fongoli. Although living in an extreme and seasonally more variable environment, Fongoli Chimpanzees were more seasonably stable in their c-peptide values than Tai Chimpanzees, but showed more extreme variation in their cortisol values. Although Chimpanzees at both sites demonstrated significant seasonal effects of dehydration (creatinine), the more extreme environmental variation at Fongoli promoted higher physiological seasonal costs in the form of elevated cortisol levels. Overall, these results supported the assertion that Fongoli as a savanna-mosaic habitat is more extreme in its climate and ecology than a forested site. It appears that extreme savanna-mosaic habitats represent a limit to the Chimpanzee ecological niche with regard to thermoregulation, in that seasonal environmental conditions, namely the hot and dry conditions of the dry season, strain an individual’s ability to maintain homeostasis. However, Tai Chimpanzees also faced dehydration as a limitation, which highlights that Chimpanzees may experience certain challenges ubiquitously across their range, while other challenges remain habitat-specific. Hence, categorizing savanna habitats as universally more severe and challenging to Chimpanzees than more heavily forested habitats does not yet appear to be warranted.
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Intragroup Lethal Aggression in West African Chimpanzees (Pan troglodytes verus): Inferred Killing of a Former Alpha Male at Fongoli, Senegal
2017Co-Authors: Jill D. Pruetz, Stacy M. Lindshield, Kelly Boyer Ontl, Elizabeth Cleaveland, Joshua Marshack, Erin G WesslingAbstract:Lethal coalitionary aggression is of significant interest to primatologists and anthropologists given its pervasiveness in human, but not nonhuman, animal societies. Chimpanzees ( Pan troglodytes ) provide the largest sample of recorded lethal coalitionary aggression in nonhuman primates, and most long-term Chimpanzee study sites have recorded coalitionary killing of conspecifics. We report an inferred lethal attack by resident males on a former alpha male Chimpanzee ( P. t. verus ) at Fongoli in Senegal. We describe the male’s presence in the community, his overthrow, social peripheralization for >5 yr, and his attempt to rejoin the group as well as circumstances surrounding his death. We report attacks by multiple Chimpanzees on his dead body, most frequently by a young adult male and an older female. The latter also cannibalized the body. Coalitionary killing is rare among West African Chimpanzees compared to the East African Chimpanzee ( P. t. schweinfurthii ). This pattern may relate to differences in population densities, research effort, and subspecies differences in biology and behavior.
