Upon detection of disturbances in their surroundings, such as the appearance of a dog or a snake, Barbary macaques (Macaca sylvanus) living in the outdoor enclosure of Rocamadour, France, utter series of ‘shrill barks’. In some cases, the... more
Upon detection of disturbances in their surroundings, such as the appearance of a dog or a snake, Barbary macaques (Macaca sylvanus) living in the outdoor enclosure of Rocamadour, France, utter series of ‘shrill barks’. In some cases, the majority of group members react by running away or climbing up a tree. In many other instances, however, group members apparently ignore the calls. We conducted a set of playback experiments to identify the factors underlying subjects’ responses. In these experiments, we presented calls (a) given in response to dogs that had elicited escape responses, (b) calls given in response to dogs that had failed to elicit escape responses, (c) calls given to snakes and (d) calls given to the observer approaching the sleeping trees at night. An acoustic analysis of the calls presented in the playback experiments revealed significant differences among calls given to dogs, the observer approaching at night and snakes. However, it failed to detect differences between calls given to dogs in relation to whether or not they had initially elicited escape responses. Correspondingly, after playback of calls given to dogs, we observed no difference in subjects’ responses in relation to whether or not the calls had elicited escape responses in the first place. Subjects responded significantly more strongly to playbacks of calls given to dogs than to calls given to observers. Playbacks of calls to snakes failed to elicit specific responses. Our findings suggest that responses are dependent on the external referent, but that there is no clear-cut relationship between the information available to the listeners and their subsequent responses. This insight forces us to revise current approaches to identifying the meaning of animal signals. We will also discuss the similarities and differences in the alarm call system of other non-human primate species.
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A population census of chimpanzees (Pan troglodytes schweinfurthil) was conducted in the original part of Kahuzi-Biega National Park. Zaire. The census provides the first estimate of the density of chimpanzees in montane forests of... more
A population census of chimpanzees (Pan troglodytes schweinfurthil) was conducted in the original part of Kahuzi-Biega National Park. Zaire. The census provides the first estimate of the density of chimpanzees in montane forests of Equatorial Africa. At least three unit groups of chimpanzees were identified in the census area during the 1990 bamboo season. The estimated density (0.13 chimpanzees/km2) falls within the range of densities in savanna. the driest chimpanzee habitat. The estimated density was far lower than the density of gorillas that sympatrically inhabit this montane forest. even though the two apes have been found at almost equal density in tropical forests in other areas. Chim-panzees were typical forest-dwellers. but gorillas ranged over various types of vegetation. in-cluding the open vegetation and the swamp. The low diversity and availability of fruits in the montane forest are responsible for the low density of chimpanzees who are frugivorous in various habitats...
The contents of this report do not necessarily reflect the views or policies of UNEP or contributory organisations. The designations employed and the presentations do not imply the expressions of any opinion whatsoever on the part of UNEP... more
The contents of this report do not necessarily reflect the views or policies of UNEP or contributory organisations. The designations employed and the presentations do not imply the expressions of any opinion whatsoever on the part of UNEP or contributory organisations concerning the legal status of any country, territory, city, company or area or its authority, or concern-ing the delimitation of its frontiers or boundaries.
Conservation science is increasingly recognizing the importance of landscapebased and ecosystem approaches to managing certain protected areas. In some cases, implementing such approaches means transcending ecologically arbitrary... more
Conservation science is increasingly recognizing the importance of landscapebased and ecosystem approaches to managing certain protected areas. In some cases, implementing such approaches means transcending ecologically arbitrary boundaries and managing across national boundaries. Conservation-related activities —such as tourism, biodiversity monitoring, and law enforcement to curb illegal exploitation of natural resources—have an added benefit: they can provide a more comfortable focus for transboundary collaboration than more delicate issues, such as the minerals trade and the exploitation of energy resources. In regions suffering from armed conflict, transboundary conservation management has paved the way toward greater collaboration and stability. For instance, joint management of the Cordillera del Cóndor transboundary protected area (TBPA), a remote rainforest shared by Peru and Ecuador, helped to settle an intermittently violent border dispute that persisted for 170 years. So...
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Over the last half-century, the world’s human population has doubled, impacting almost all ocean and land areas. The threats facing primates in the wild have never been greater or more complex. Primatologists have long been aware of these... more
Over the last half-century, the world’s human population has doubled, impacting almost all ocean and land areas. The threats facing primates in the wild have never been greater or more complex. Primatologists have long been aware of these threats and, since the 1970s, have coordinated efforts to safeguard these threatened species, through the International Union for Conservation of Nature Species Survival Commission (IUCN SSC) Primate Specialist Group (PSG). In an effort to stem the threat of extinction to primates, this group of now 700 experts+ has published 17 conservation action plans since 1977. As we look toward the next half-century, we take stock of the history of primate action planning to better understand the costs and benefits of these plans as a conservation tool. Here, we reviewed all plans published by the IUCN SSC PSG. In total, they described USD 246 million in planned primate conservation programming and were cited 1657 times by others. We found that half of the pl...
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Water plays a vital role in many aspects of sustaining life, including thermoregulation. Given that increasing temperatures and more extreme weather events due to climate change are predicted to influence water availability, understanding... more
Water plays a vital role in many aspects of sustaining life, including thermoregulation. Given that increasing temperatures and more extreme weather events due to climate change are predicted to influence water availability, understanding how species obtain and use water is critical. This is especially true for endangered species in small isolated populations which are vulnerable to drought and the risk of extinction. We examined the relationship between the frequency of water drinking and maximum temperature and rainfall in 21 groups of wild gorillas from the two mountain gorilla populations (Bwindi and Virunga), between 2010 and 2020. In both populations, we found that the frequency of water drinking significantly increased at higher maximum temperatures than cooler ones, but we found no consistent relationship between water drinking and rainfall. We also found that Virunga gorillas relied more on foods with higher water content than Bwindi gorillas, which in part likely explains ...
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Threats to biodiversity are well documented. However, to effectively conserve species and their habitats, we need to know which conservation interventions do (or do not) work. Evidence-based conservation evaluates interventions within a... more
Threats to biodiversity are well documented. However, to effectively conserve species and their habitats, we need to know which conservation interventions do (or do not) work. Evidence-based conservation evaluates interventions within a scientific framework. The Conservation Evidence project has summarized thousands of studies testing conservation interventions and compiled these as synopses for various habitats and taxa. In the present article, we analyzed the interventions assessed in the primate synopsis and compared these with other taxa. We found that despite intensive efforts to study primates and the extensive threats they face, less than 1% of primate studies evaluated conservation effectiveness. The studies often lacked quantitative data, failed to undertake postimplementation monitoring of populations or individuals, or implemented several interventions at once. Furthermore, the studies were biased toward specific taxa, geographic regions, and interventions. We describe ba...
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ABSTRACTWe studied the impact of hunting on monkey species in the Taï National Park and adjacent forests in Côte d'Ivoire. The average wild meat consumption per capita per year was assessed from market surveys and interviews. We... more
ABSTRACTWe studied the impact of hunting on monkey species in the Taï National Park and adjacent forests in Côte d'Ivoire. The average wild meat consumption per capita per year was assessed from market surveys and interviews. We determined that the amount of primate wild meat being extracted in the Taï National Park and surrounding forests was 249 t in 1999. Hunting pressure was the highest on the larger primate species such as red colobus, Procolobus badius, black and white colobus, Colobus polykomos, and the sooty mangabey, Cercocebus torquatus atys. Estimates of population densities were based on line transect surveys. The maximum annual production of each species was calculated using the Robinson and Redford model (1991) and assuming unhunted conditions. Comparing current harvest levels with the maximum sustainable yield suggests that harvest of red colobus monkeys (Procolobus badius) is sustainable, whereas current off‐take of the black and white colobus (Colobus polykomos)...
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The COVID-19 pandemic has caused global disruption, with the emergence of this and other pandemics having been linked to habitat encroachment and/or wildlife exploitation. High impacts of COVID-19 are apparent in some countries with large... more
The COVID-19 pandemic has caused global disruption, with the emergence of this and other pandemics having been linked to habitat encroachment and/or wildlife exploitation. High impacts of COVID-19 are apparent in some countries with large tropical peatland areas, some of which are relatively poorly resourced to tackle disease pandemics. Despite this, no previous investigation has considered tropical peatlands in the context of emerging infectious diseases (EIDs). Here, we review: (i) the potential for future EIDs arising from tropical peatlands; (ii) potential threats to tropical peatland conservation and local communities from COVID-19; and (iii) potential steps to help mitigate these risks. We find that high biodiversity in tropical peat-swamp forests, including presence of many potential vertebrate and invertebrate vectors, combined, in places, with high levels of habitat disruption and wildlife harvesting represent suitable conditions for potential zoonotic EID (re-)emergence. A...
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Non-human great apes – chimpanzees, gorillas, bonobos, and orangutans – are threatened by agricultural expansion particularly from rice, cacao, cassava, maize, and oil palm cultivation. Agriculture replaces and fragments great ape... more
Non-human great apes – chimpanzees, gorillas, bonobos, and orangutans – are threatened by agricultural expansion particularly from rice, cacao, cassava, maize, and oil palm cultivation. Agriculture replaces and fragments great ape habitats, bringing them closer to humans and often resulting in conflict. Though the impact of agriculture on great apes is well-recognized, there is still a need for more nuanced understanding of specific contexts and associated effects on habitats and populations. Here we review these contexts and highlight synergistic and antagonistic co-occurrences between agriculture, both subsistence and commercial, and great apes. We estimate that one individual great ape shares its habitat with about 100 people, mostly outside protected areas. This makes it challenging to balance the needs of both humans and great apes given the growing human population and increasing demand for resources. Further habitat loss is expected, particularly in Africa, where compromises ...
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A population census of chimpanzees (Pan troglodytes schweinfurthil) was conducted in the original part of Kahuzi-Biega National Park. Zaire. The census provides the first estimate of the density of chimpanzees in montane forests of... more
A population census of chimpanzees (Pan troglodytes schweinfurthil) was conducted in the original part of Kahuzi-Biega National Park. Zaire. The census provides the first estimate of the density of chimpanzees in montane forests of Equatorial Africa. At least three unit groups of chimpanzees were identified in the census area during the 1990 bamboo season. The estimated density (0.13 chimpanzees/km2) falls within the range of densities in savanna. the driest chimpanzee habitat. The estimated density was far lower than the density of gorillas that sympatrically inhabit this montane forest, even though the two apes have been found at almost equal density in tropical forests in other areas. Chimpanzees were typical forest-dwellers, but goriiias ranged over various types of vegetation, including the open vegetation and the swamp. The low diversity and availability of fruits in the montane forest are responsible for the low density of chimpanzees who are frugivorous in various habitats. ...
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Advancing technology represents an unprecedented opportunity to enhance our capacity to conserve the Earth's biodiversity. However, this great potential is failing to materialize and rarely endures. We contend that unleashing the... more
Advancing technology represents an unprecedented opportunity to enhance our capacity to conserve the Earth's biodiversity. However, this great potential is failing to materialize and rarely endures. We contend that unleashing the power of technology for conservation requires an internationally coordinated strategy that connects the conservation community and policy-makers with technologists. We argue an international conservation technology entity could (1) provide vision and leadership, (2) coordinate and deliver key services necessary to ensure translation from innovation to effective deployment and use of technology for on-the-ground conservation across the planet, and (3) help integrate innovation into biodiversity conservation policy from local to global scales, providing tools to monitor outcomes of conservation action and progress towards national and international biodiversity targets. This proposed entity could take the shape of an international alliance of conservation...
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Research Interests: Geography, Biodiversity, Gorilla, Ecosystems, Land Use, and 3 moreHabitats, Threatened Species, and Apes
As a result of forest modification, primates are increasingly having to rely on fragments; so too are the human populations that have historically relied on continuous forest for critical resources. The role of primates in seed dispersal... more
As a result of forest modification, primates are increasingly having to rely on fragments; so too are the human populations that have historically relied on continuous forest for critical resources. The role of primates in seed dispersal is increasingly understood to have significant unique effects on plant demography and forest regeneration. Our aim in this paper is to explore the potential for monkey seed dispersers to maintain the utility of forest fragments for humans through seed dispersal in the Taï region, western Côte-d'Ivoire. We established a list of fruit species whose seeds are dispersed by seven of eight monkey species occurring in the Taï National Park by using primary data and published accounts of their fruit diet, and determined the abundance of human-used and monkey-dispersed tree species in forest fragments in the broader Taï region. The monkeys of the Taï National Park consumed 75 tree species. Of this total set of 75 species, 52 (69%) were dispersed almost e...