Human-chimpanzee coexistence at Bossou, the Republic of Guinea: a chimpanzee perspective

The increasing rate of human population growth has expanded the human-primate interface, with more conversion of natural primate habitat to agricultural land. Elevated levels of crop-raiding by primates are a by-product of natural resources becoming less available, and the nutritional riches of agricultural production becoming increasingly known to the primates. It was the aim of this thesis to focus on the Bossou chimpanzees’ (Pan troglodytes verus) perspective of their habitat in the Republic of Guinea, West Africa, the risks and opportunities presented by a human-dominated landscape, and to detail their day-to-day coexistence with humans. I combined a variety of data collection techniques, from focal, scan and ad libitum behavioural sampling of the chimpanzees’ daily activities, to broad ecological and habitat surveys. The chimpanzees rely on cultivated foods, and thus are forced to respond to humans. However, significant variation in the importance of various cultivars in the chimpanzees’ diet exists; certain cultivars are mostly fallback foods, while others are preferred food items and taken according to their availability in orchards and fields. The usage patterns of wild and cultivated foods by the chimpanzees of Bossou are thus inextricably connected. Whilst engaged in crop-raiding the chimpanzees exhibit several behavioural adaptations, namely a decrease in vocalisation levels, and increases in the transportation of food and specific vigilance behaviour. Adult males and adult male-only parties crop-raid more than other age- and sex-classes/compositions, and are more likely to take risks by raiding in exposed environments with increased risk of human confrontation. The use of human cultivars also affects the socio-sexual behaviour of the chimpanzees: chimpanzees appear to share the fruits of their risky labours (crop-raiding) as a food-for-sex strategy, which allow adult males to advertise prowess and enhance affiliative relationships with reproductively valuable females (Hockings et al., in prep). In addition, behavioural adaptations to other anthropogenic high-risk situations such as road-crossing were found, with the chimpanzees exhibiting impressive levels of socio-spatial flexibility and cooperation (Hockings et al., 2006). The chimpanzees’ level of anxiety (as measured by rough self-directed scratching) increases when dealing with some of the challenges posed by their physical and social environment. The chimpanzees of Bossou have been forced to adapt ecologically and behaviourally to the various costs and benefits of living in a human-dominated environment.This study was made possible by a studentship provided by the Department of Psychology at the University of Stirling, and fieldwork expenses provided by Professor Matsuzawa (from JSPS-HOPE and MEXT (#16002001))

Inter-community behavioural variation confirmed through indirect methods in four neighbouring chimpanzee communities in Cantanhez NP, Guinea-Bissau

UIDB/04038/2020 UIDP/04038/2020Culture, while long viewed as exclusively human, has now been demonstrated across diverse taxa and contexts. However, most animal culture data are constrained to well-studied, habituated groups. This is the case for chimpanzees, arguably the most ‘cultural’ non-human species. While much progress has been made charting wild chimpanzees' cultural repertoire, large gaps remain in our knowledge of the majority of the continent's chimpanzees. Furthermore, few studies have compared neighbouring communities, despite such comparisons providing the strongest evidence for culture, and few have studied communities living in anthropogenic habitats although their culture is in imminent danger of disappearing. Here we combine direct, indirect and remote methods, including camera traps, to study, over 2 years, four unhabituated neighbouring chimpanzee communities inhabiting human-impacted habitats in Cantanhez NP, Guinea-Bissau. From traces collected during 1089 km of reconnaissance walks and 4197 videos from 56 camera trap locations, we identified 18 putative cultural traits. These included some noteworthy novel behaviours for these communities, and behaviours possibly new to the species. We created preliminary behavioural profiles for each community, and found inter-community differences spanning tool use, communication, and social behaviour, demonstrating the importance of comparing neighbouring communities and of studying previously neglected communities including those inhabiting anthropogenic landscapes.publishersversionpublishe

From Forest to Farm: Systematic Review of Cultivar Feeding by Chimpanzees – Management Implications for Wildlife in Anthropogenic Landscapes

Crop-raiding is a major source of conflict between people and wildlife globally, impacting local livelihoods and impeding conservation. Conflict mitigation strategies that target problematic wildlife behaviours such as crop-raiding are notoriously difficult to develop for large-bodied, cognitively complex species. Many crop-raiders are generalist feeders. In more ecologically specialised species crop-type selection is not random and evidence-based management requires a good understanding of species' ecology and crop feeding habits. Comprehensive species-wide studies of crop consumption by endangered wildlife are lacking but are important for managing human–wildlife conflict. We conducted a comprehensive literature search of crop feeding records by wild chimpanzees (Pan troglodytes), a ripe-fruit specialist. We assessed quantitatively patterns of crop selection in relation to species-specific feeding behaviour, agricultural exposure, and crop availability. Crop consumption by chimpanzees is widespread in tropical Africa. Chimpanzees were recorded to eat a considerable range of cultivars (51 plant parts from 36 species). Crop part selection reflected a species-typical preference for fruit. Crops widely distributed in chimpanzee range countries were eaten at more sites than sparsely distributed crops. We identified ‘high’ and ‘low’ conflict crops according to their attractiveness to chimpanzees, taking account of their importance as cash crops and/or staple foods to people. Most (86%) high conflict crops were fruits, compared to 13% of low conflict crops. Some widely farmed cash or staple crops were seldom or never eaten by chimpanzees. Information about which crops are most frequently consumed and which are ignored has enormous potential for aiding on-the-ground stakeholders (i.e. farmers, wildlife managers, and conservation and agricultural extension practitioners) develop sustainable wildlife management schemes for ecologically specialised and protected species in anthropogenic habitats. However, the economic and subsistence needs of local people, and the crop-raiding behaviour of sympatric wildlife, must be considered when assessing suitability of particular crops for conflict prevention and mitigation

Wild chimpanzees show group differences in selection of agricultural crops

UID/ANT/04038/2013The ability of wild animals to respond flexibly to anthropogenic environmental changes, including agriculture, is critical to survival in human-impacted habitats. Understanding use of human foods by wildlife can shed light on the acquisition of novel feeding habits and how animals respond to human-driven land-use changes. Little attention has focused on within-species variation in use of human foods or its causes. We examined crop-feeding in two groups of wild chimpanzees-a specialist frugivore-with differing histories of exposure to agriculture. Both groups exploited a variety of crops, with more accessible crops consumed most frequently. However, crop selection by chimpanzees with long-term exposure to agriculture was more omnivorous (i.e., less fruit-biased) compared to those with more recent exposure, which ignored most non-fruit crops. Our results suggest chimpanzees show increased foraging adaptations to cultivated landscapes over time; however, local feeding traditions may also contribute to group differences in crop-feeding in this species. Understanding the dynamic responses of wildlife to agriculture can help predict current and future adaptability of species to fast-changing anthropogenic landscapes.publishersversionpublishe

Environmental psychology must better integrate local cultural and sociodemographic context to inform conservation

UID/ANT/04038/2013 EXPL/IVC-ANT/0997/2013publishersversionpublishe

current research and future directions

SFRH/BPD/38595/2007 PPCDT/ANT/57434/2004 PEst-OE/SADG/UI4038/2011Increasing human populations and the rapid conversion of forest to agricultural land increase the likelihood of interactions and conflict between humans and nonhuman primates. Understanding such interactions requires a broad cross-disciplinary approach that assesses the implications of sympatry for primate conservation and human social, cultural and economic needs. Although chimpanzees were declared extinct in Guinea-Bissau in 1988, recent reports estimate that between 600 and 1,000 individuals are currently present, with the largest population occupying the Cantanhez National Park (105,700 ha; northeast limit: 11°22′58″N,14°46′12″W; southwest limit: 11°2′18″N,15°15′58″W). These heavily fragmented coastal forests have been identified as one of seven priority areas in West Africa for urgent chimpanzee conservation efforts (Kormos et al. 2003. West African Chimpanzees. Status Survey and Conservation Action Plan. IUCN, Gland. 2003). Here we set the context for human-chimpanzee sympatry in Guinea-Bissau, and provide a platform from which further studies can expand. We review past findings that might affect current and future sympatric relationships, and integrate preliminary data on resource competition from one hitherto unstudied chimpanzee (Pan troglodytes verus) community inhabiting a forested-agricultural matrix in Caiquene and Cadique, central Cantanhez National Park. While local human cultural traditions provide a degree of tolerance and protection to chimpanzees in Cantanhez National Park, which is beneficial for long-term conservation initiatives, human-chimpanzee interactions have the potential to grow increasingly negative in character, especially as human populations expand and further pressure is exerted on the land.publishersversionpublishe

Implications for the Management of Complex Social-Ecological Systems

UIDB/04038/2020 UIDP/04038/2020 IF/01128/2014 PTDC/CS-ANT/121124/2010 CRIA/04038/BPD/DASEUnderstanding the capacity for humans to share resources (crops, wild foods, space) with large-bodied wildlife is vital for biodiversity conservation and human wellbeing, and requires comprehensive examination of their temporal interactions over fine spatial scales. We combined ecological (plant identification, wild fruit availability plots, animal fecal and trace sampling) and social science (free-listing, semi-structured interviews, participant observation) methods to systematically and simultaneously collect data on the availability and selection of fruits from wild plants by humans and critically endangered chimpanzees (Pan troglodytes verus), a national conservation flagship species at Cantanhez National Park, Guinea-Bissau. Within an area of 12.7 km2, we demonstrate that local people’s monthly use of wild fruits was driven by its overall availability in the habitat, whereas chimpanzees, as ripe fruit specialists, sought out fruits year-round. Humans and chimpanzees overlap in the selection of fruits from at least 27 wild plant species. The ranked use of fruits from species which were used by both chimpanzees and humans was significantly positively correlated, suggesting they preferentially target fruits of the same wild plant species. Each month, humans and chimpanzees selected three to six of the same wild fruit species. Chimpanzees fed significantly more on wild fruit species that were available for longer periods, with no effect of that plant species density. Neither plant density nor number of fruiting months impacted human selection of fruit from a plant species, suggesting people might seek out desired resources irrespective of a species’ abundance in the landscape. These findings are important for the development of a shared knowledge base to establish culturally relevant conservation management strategies. We recommend the active management of plant species that are exploited for their fruits by both humans and chimpanzees at Cantanhez National Park, including figs (Ficus spp.), oil-palm (Elaeis guineensis) and velvet tamarind (Dialium guineense). This can be achieved through supporting traditional resource management practices and the strategic replanting of shared plants in deforested areas and degraded corridors between forest fragments. This situation is representative of human-chimpanzee coexistence scenarios found across West Africa; the importance of shared resource use should be incorporated into local, national and regional conservation strategies.publishersversionpublishe

Mixed-ethnicity face shape and attractiveness in humans

Many studies show agreement within and between populations and cultures for general judgments of facial attractiveness. Studies that have examined the attractiveness of specific traits have also highlighted cross-cultural differences for factors such as symmetry, averageness, and masculinity. One trait that should be preferred across cultures is heterozygosity. Indeed, several studies suggest that mixed ethnicity, in terms of appearing to possess a mixture of traits from different human population groups, may be found attractive, which could reflect preferences for heterozygosity. We examined preferences for manipulated face shape associated with different populations in both Europeans (Britain) and Africans (Guinea-Bissau). We found that mixed-ethnicity face shapes were more attractive than enhanced single-ethnicity face shape across both populations. These results are consistent with evolutionary theories suggesting individuals should prefer heterozygosity in partners because facial cues to mixed-ethnicity are likely to indicate diverse genes compared to cues that indicate a face belongs to a single particular culture or population

Quantifying the road‐effect zone for a critically endangered primate

The global road network is expanding at an unprecedented rate, threatening the persistence of many species. Yet, even for the most endangered wildlife, crucial information on the distance up to which roads impact species abundance is lacking. Here we use ecological threshold analysis to quantify the road-effect zone (REZ) for the critically endangered western chimpanzee (Pan troglodytes verus). We found: (1) the REZ extends 5.4 km (95% CI [4.9–5.8 km]) from minor roads and 17.2 km (95% CI [15.8–18.6]) from major roads, the latter being more than three times wider than a previous estimate of the average REZ for mammals; and (2) only 4.3% of the chimpanzees’ range is not impacted by existing roads. These findings reveal the high sensitivity and susceptibility of nonhuman primates to roads across West Africa, a region undergoing rapid development, and can inform the implementation of more effective guidelines to mitigate road impacts