Explore the vast range of titles available.

Discussions of how animal culture can aid the conservation crisis are burgeoning. As scientists and conservationists working to protect endangered species, we call for reflection on how the culture concept may be applied in practice. Here, we discuss both the potential benefits and potential shortcomings of applying the animal culture concept, and propose a set of achievable milestones that will help guide and ensure its effective integration existing conservation frameworks, such as Adaptive Management cycles or Open Standards.

Chimpanzee insectivory is seasonally variable, with pronounced peaks or set seasonal periods of consumption observed in most chimpanzee communities. This variation is interesting given that chimpanzees invest considerable effort into complex tool‐using behaviors to acquire insect prey. Evidence suggests this seasonal variation is related to insect behavior, but few studies have been done to empirically examine this relationship. In this study, we assessed whether a seasonal pattern of termite fishing by Nigeria‐Cameroon chimpanzees (Pan troglodytes ellioti) in Mbam & Djerem National Park, Cameroon was driven by termite behavior. We measured termite presence and termite foraging activity monthly at seven termite mounds near Ganga Research Station from April 2022 to April 2023. Macroscopic fecal analysis and camera traps placed at each mound demonstrated termite fishing in this community occurred from March to June, with a rare smaller period of termite fishing in October 2021. Average monthly rainfall, average monthly temperature, and average monthly fruit availability were used to examine potential environmental factors that could impact termite fishing seasonality. Termite presence was significantly different between months with and without chimpanzee termite fishing (t‐test, −6.569, p < .001). Termite presence was also significantly associated with average monthly rainfall (ANOVA, F = 13.9, p = .002, R2 = .775). Termites in this region appear to respond to the transition from dry to wet seasons by moving closer to the soil surface. This corresponds with greater chimpanzee termite fishing, suggesting that termite accessibility may be driving seasonal variation in this behavior. Using an interdisciplinary approach involving remote camera trap monitoring, termite behavioral surveys, and ecological surveys, we identified key ecological factors related to a pronounced seasonal period of termite fishing in a community of the understudied Nigeria‐Cameroon chimpanzee in central Cameroon. Our results suggest the highly seasonal nature of chimpanzee termite fishing in this region is driven by seasonal variation in termite behavior mediated by rain, which makes termites more accessible to chimpanzees during periods of intermediate rainfall.

Forest loss and overhunting are eroding African tropical biodiversity and threatening local human food security, livelihoods, and health. Emblematic of this ecological crisis is Africa's most endangered group of monkeys, the red colobus (genus Piliocolobus). All 17 species, found in forests from Senegal in the west to the Zanzibar archipelago in the east, are threatened with extinction. Red colobus are among the most vulnerable mammals to gun hunting, typically disappearing from heavily hunted forests before most other large‐bodied animals. Despite their conservation status, they are rarely a focus of conservation attention and continue to be understudied. However, red colobus can act as critical barometers of forest health and serve as flagships for catalyzing broader African tropical forest conservation efforts. We offer a plan for conservation of red colobus and their habitats and discuss conservation and policy implications.

Background Chimpanzees ( Pan troglodytes ) can be divided into four subspecies. Substantial phylogenetic evidence suggests that these subspecies can be grouped into two distinct lineages: a western African group that includes P. t. verus and P. t. ellioti and a central/eastern African group that includes P. t. troglodytes and P. t. schweinfurthii . The geographic division of these two lineages occurs in Cameroon, where the rages of P. t. ellioti and P. t. troglodytes appear to converge at the Sanaga River. Remarkably, few population genetic studies have included wild chimpanzees from this region. Results We analyzed microsatellite genotypes of 187 wild, unrelated chimpanzees, and mitochondrial control region sequencing data from 604 chimpanzees. We found that chimpanzees in Cameroon and eastern Nigeria comprise at least two, and likely three populations. Both the mtDNA and microsatellite data suggest that there is a primary separation of P. t. troglodytes in southern Cameroon from P. t. ellioti north and west of the Sanaga River. These two populations split ~200-250 thousand years ago (kya), but have exchanged one migrant per generation since separating. In addition, P. t. ellioti consists of two populations that split from one another ~4 kya. One population is located in the rainforests of western Cameroon and eastern Nigeria, whereas the second population appears to be confined to a savannah-woodland mosaic in central Cameroon. Conclusions Our findings suggest that there are as many as three genetically distinct populations of chimpanzees in Cameroon and eastern Nigeria. P. t. troglodytes in southern Cameroon comprises one population that is separated from two populations of P. t. ellioti in western and central Cameroon, respectively. P. t. ellioti and P. t. troglodytes appear to be characterized by a pattern of isolation-with-migration, and thus, we propose that neutral processes alone can not explain the differentiation of P. t. ellioti and P. t. troglodytes .

Examining the diets of primate populations inhabiting different habitat types could be useful in understanding local adaptation and divergence between these populations. In Cameroon, the Nigeria–Cameroon chimpanzee (Pan troglodytes ellioti) is subdivided into two genetically distinct populations that occupy different habitat types; one occurs in forests to the west and the other in a forest–woodland–savanna mosaic (ecotone) in the center of the country. We used macroscopic fecal sample assessment to investigate dietary differences in relation to monthly fruit availability among P. t. ellioti communities in both habitat types: at Ebo Forest (rainforest) and Mbam and Djerem National Park (ecotone). We collected data simultaneously across three sites: Bekob and Njuma (rainforest) and Ganga (ecotone) from January 2016 to December 2017. In the dry season, fruits were the most important dietary component at Bekob and Njuma, while nonfruit plant material (leaves, pith, and bark) were most important at Ganga. In the wet season, the proportion of fruits in the diet was greatest at Ganga, while nonfruit plant material dominated chimpanzee diets at Bekob and Njuma. Chimpanzees at Bekob ate more fruits from introduced and secondary forest plant species than those at Njuma and Ganga, especially during periods of fruit scarcity. Animal consumption was higher at Ganga and was inversely associated with fruit consumption. These observations link habitat diversity to differences in feeding ecology among genetically distinct populations of P. t. ellioti. We speculate that dietary differences reflect broader socioecological variation between these populations, and collectively, that these factors promote intraspecific divergence.

Complex ecological pressures affect the social dynamics of many primate species, but it is unclear how they affect primate speciation. Molecular tools are often used to answer questions about the evolutionary histories and social systems of primates. Mitochondrial DNA (mtDNA), in particular, is frequently used to answer many of these questions, but because it is passed from mothers to offspring it reveals only the histories of females. In many species, including chimpanzees, females generally disperse from their natal groups while males are philopatric, and thus differences in dispersal patterns likely leave different signatures in the genome. We previously analyzed samples from 187 unrelated male and female chimpanzees in Nigeria and Cameroon using 21 autosomal microsatellites and mtDNA sequences. Here, we examine the contributions of males and females in shaping the genetic history of these chimpanzees by genotyping a subset of 56 males at 12 Y-chromosome microsatellites. We found that Y-chromosome population structure differed from the results of analysis of mtDNA haplotypes. The results also revealed that males in rainforest habitats (Guinean and Congolian rainforests) are more closely related to one another than those inhabiting the savanna-woodland mosaic ecotone in central Cameroon. In contrast, the pattern of female relatedness did not differ across habitats. We hypothesize that these differences in population structure and patterns of relatedness among males in different habitat types may be due to differences in the community dynamics of chimpanzees in the ecotone vs. rainforests, and that these factors contribute to making Cameroon an engine of diversification for chimpanzees. Broadly, these results demonstrate the importance of habitat variation in shaping social systems, population genetics, and primate speciation.

Ecological niche models (ENMs) are often used to predict species distribution patterns from datasets that describe abiotic and biotic factors at coarse spatial scales. Ground‐truthing ENMs provide important information about how these factors relate to species‐specific requirements at a scale that is biologically relevant for the species. Chimpanzees are territorial and have a predominantly frugivorous diet. The spatial and temporal variation in fruit availability for different chimpanzee populations is thus crucial, but rarely depicted in ENMs. The genetic and geographic distinction within Nigeria–Cameroon chimpanzee (Pan troglodytes ellioti) populations represents a unique opportunity to understand fine scale species‐relevant ecological variation in relation to ENMs. In Cameroon, P. t. ellioti is composed of two genetically distinct populations that occupy different niches: rainforests in western Cameroon and forest–woodland–savanna mosaic (ecotone) in central Cameroon. We investigated habitat variation at three representative sites using chimpanzee‐relevant environmental variables, including fruit availability, to assess how these variables distinguish these niches from one another. Contrary to the assumption of most ENM studies that intact forest is essential for the survival of chimpanzees, we hypothesized that the ecotone and human‐modified habitats in Cameroon have sufficient resources to sustain large chimpanzee populations. Rainfall, and the diversity, density, and size of trees were higher at the rainforest. The ecotone had a higher density of terrestrial herbs and lianas. Fruit availability was higher at Ganga (ecotone) than at Bekob and Njuma. Seasonal variation in fruit availability was highest at Ganga, and periods of fruit scarcity were longer than at the rainforest sites. Introduced and secondary forest species linked with anthropogenic modification were common at Bekob, which reduced seasonality in fruit availability. Our findings highlight the value of incorporating fine scale species‐relevant ecological data to create more realistic models, which have implications for local conservation planning efforts. We examined specific abiotic factors and biotic conditions predicted by ecological niche models (ENMs) to differentiate two distinct genetically distinct populations of the Nigeria–Cameroon chimpanzee (Pan troglodytes ellioti) at a fine geographic scale using chimpanzee‐relevant variables, such as fruit availability. The results revealed that while ENMs are useful for understanding habitat suitability at a broad scale, more attention needs to be given to incorporating species‐specific requirements at a spatial and temporal scale that is biologically relevant for the species.

Increased human activities such as commodity-led deforestation, extension of agriculture, urbanization, and wildfires are major drivers of forest loss worldwide. In Cameroon, these activities cause a loss of suitable primate habitat and could ultimately threaten the survival of chimpanzees (Pan troglodytes). We derived independent estimates of the population size of the Endangered Nigeria–Cameroon chimpanzee (Pan troglodytes ellioti) in Kom-Wum Forest Reserve, Cameroon, and surrounding unprotected forest areas through 1) direct observations, 2) camera trapping, 3) distance sampling, 4) marked nest counts, and 5) standing crop nest counts. In addition, we georeferenced signs of chimpanzee and human activity along line transects. We used a generalized linear mixed model to predict the occurrence of chimpanzees in response to edge length (measured as the perimeter of core forest patches), core area of forest patches (measured as area of forest patches beyond an edge width of 100 m), habitat perforation (measured as the perimeter of nonforested landscape within core forest patches), patch size(measured as area of forest patches), and forest cover. Chimpanzee density estimates ranged from 0.1 (direct observation) to 0.9 (distance sampling) individuals km−2 depending on estimation method with a mean nest group size of 7 ± 5.4 (SD). The mean encounter rate for signs of chimpanzee activity was significantly higher in mature forests (2.3 signs km−1) than in secondary forests (0.3 signs km−1) and above 1000 m elevation (4.0 signs km−1) than below 1000 m (1.0 signs km−1). The mean encounter rate for signs of human activity was significantly higher in secondary (8.0 signs km−1) than in mature forests (0.9 signs km−1). Secondary forests, habitat perforation, and edge length had a significant negative effect on the occurrence of chimpanzee signs. Overall, human activity and forest degradation affected the number of observed chimpanzee signs negatively. Regular antipoaching patrols and reforestation programs in degraded areas could potentially reduce threats to populations of endangered species and may increase suitable habitat area.

Background The Nigeria-Cameroon chimpanzee ( Pan troglodytes ellioti) is found in the Gulf of Guinea biodiversity hotspot located in western equatorial Africa. This subspecies is threatened by habitat fragmentation due to logging and agricultural development, hunting for the bushmeat trade, and possibly climate change. Although P. t. ellioti appears to be geographically separated from the neighboring central chimpanzee ( P. t. troglodytes ) by the Sanaga River, recent population genetics studies of chimpanzees from across this region suggest that additional factors may also be important in their separation. The main aims of this study were: 1) to model the distribution of suitable habitat for P. t. ellioti across Cameroon and Nigeria, and P. t. troglodytes in southern Cameroon, 2) to determine which environmental factors best predict their optimal habitats, and 3) to compare modeled niches and test for their levels of divergence from one another. A final aim of this study was to examine the ways that climate change might impact suitable chimpanzee habitat across the region under various scenarios. Results Ecological niche models (ENMs) were created using the software package Maxent for the three populations of chimpanzees that have been inferred to exist in Cameroon and eastern Nigeria: ( i ) P. t. troglodytes in southern Cameroon, ( ii ) P. t. ellioti in northwestern Cameroon, and ( iii ) P. t. ellioti in central Cameroon. ENMs for each population were compared using the niche comparison test in ENMtools, which revealed complete niche divergence with very little geographic overlap of suitable habitat between populations. Conclusions These findings suggest that a positive relationship may exist between environmental variation and the partitioning of genetic variation found in chimpanzees across this region. ENMs for each population were also projected under three different climate change scenarios for years 2020, 2050, and 2080. Suitable habitat of P. t. ellioti in northwest Cameroon / eastern Nigeria is expected to remain largely unchanged through 2080 in all considered scenarios. In contrast, P. t. ellioti in central Cameroon, which represents half of the population of this subspecies, is expected to experience drastic reductions in its ecotone habitat over the coming century.

Overhunting and habitat loss from the expansion of agriculture and extractive industries are the primary threats to primate species, 65% of which are threatened with extinction. In Africa, red colobus (Piliocolobus spp.) are the most endangered group of monkeys due to their vulnerability to these human pressures. The conservation status of the Critically Endangered Preuss’s red colobus (P. preussi), found in southeastern Nigeria and western Cameroon, is not well understood, impeding conservation efforts. We reviewed historical records and recent data on the distribution and abundance of Preuss’s red colobus to assess the species’ population status and provide recommendations for its conservation. Preuss’s red colobus has historically been found in two widely separated populations: one in the contiguous transboundary forests of Nigeria’s Cross River National Park (Oban) and Cameroon’s Korup National Park, and the other in Cameroon’s Ebo–Makombe–Ndokbou forests. Today, Preuss’s red colobus is mostly restricted to Korup and Oban and has largely disappeared from the Ebo–Makombe–Ndokbou forests. Systematic surveys indicate that the population in Korup, where Preuss’s red colobus reaches its highest density, has declined over the last 30 years with possibly 3290–4430 red colobus monkeys remaining. Improving protection of the Korup–Oban population, through improved law enforcement, transboundary conservation, ecological monitoring, and engagement with adjacent local communities, is essential to secure the long-term survival of Preuss’s red colobus. Locating and protecting remnant groups in other forests is also urgently needed. Protecting Preuss’s red colobus will help safeguard some of West Africa’s largest remaining intact forests and other threatened wildlife species.