The increased number of primates living in fragmented habitats necessitates greater knowledge of how they cope with large-scale changes to their environment. Chimpanzees (Pan troglodytes) are exceptionally vulnerable to forest fragmentation; however, little is known about chimpanzee feeding ecology in fragments. Although chimpanzees have been shown to prefer fruit when it is available and fall back on more abundant lower quality foods during periods of fruit scarcity, our understanding of how chimpanzees use fallback foods in forest fragments is poor. We examined how chimpanzees cope with periods of fruit scarcity in Gishwati Forest Reserve, a disturbed montane rain forest fragment in Rwanda. We assessed seasonal changes in chimpanzee diet and the use of preferred and fallback foods through fecal and food site analysis. We also examined seasonal variation in nest group size and habitat use through marked nest censuses. We found that chimpanzees experienced a seasonal reduction in preferred fruit availability, which led to a seasonal diet shift to more fibrous foods, including several that functioned as fallback foods. Our results suggest that during periods of fruit scarcity the chimpanzees also reduced nest group size. However, we found that the chimpanzees did not alter their habitat use between high-and low-fruit seasons, which suggests that the small size of the forest limits their ability to change their seasonal habitat use. Consequently, fallback foods appear to be particularly important in small food-impoverished habitats with limited ranging options.

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Chimpanzees in Gishwati disperse a significant number of large seeds. Large-bodied seed dispersers, like chimpanzees, are particularly important in regenerating forest fragments.

As great ape populations around the world continue to decline, largely due to anthropogenic activities, conservation programs aimed at supporting these efforts have had mixed success. Here, we evaluate our community‐based conservation program in Gishwati forest, Rwanda, aimed at helping to restore biodiversity and ecosystem services using chimpanzees as a flagship species. We examine the effectiveness of this program on reducing one of the ongoing threats to Gishwati's population of chimpanzees, illegal cattle grazing as well as the program's influence on the size of the chimpanzee population. We monitored illegal cattle grazing during several study periods between 2009 and 2019 in Gishwati forest following the implementation of our conservation program in 2008 that included law enforcement, community engagement, and research components. We found that when our conservation program was active, illegal cattle grazing was reduced to low levels. We also observed an increase in the chimpanzee population size during the 11 years since we started our conservation program. We examine how this reduction in cattle grazing and increase in chimpanzee population size may have been influenced by our community‐centered approach and discuss the future of our conservation work in Gishwati.

Aim As part of the Gaborone Declaration for Sustainability in Africa, Liberia has pledged to include the value of nature in national decision making through natural capital accounting. Surveying species of concern, such as the western chimpanzee (Pan troglodytes verus), which was recently reclassified as “critically endangered” by the International Union for Conservation of Nature, and identifying protection priority areas are critical first steps towards achieving Liberia's goal to conserve 30% of its remaining forests and supporting the wave of conservation projects taking place in the country. Location Liberia, Africa. Methods We modelled western chimpanzee habitat suitability, focusing on determining relevant environmental predictors and the most appropriate scale for modelling species–habitat relationships. We built models at six resolutions (30–960 m) to identify scale domains where relationships remain constant. We include several habitat variables that have not been included in prior modelling efforts. We then used the suitability map as the conductance input into a connectivity analysis using Circuitscape. Results The amount of forest within 1–3 km was the most important predictor of chimpanzee occurrence. Variable ranks and importance shifted considerably between modelling scales, supporting the need for multiscale investigations, but scale domains were present. Several important corridors for chimpanzee habitat and movement overlap considerably with existing timber and palm oil concessions and overlap mining and rubber concessions to a lesser degree. Main conclusions The proportion of primary forest within 1–3 km is critically important for chimpanzee habitat. Ongoing conservation projects and efforts taking place in Liberia including the Good Growth Partnership and the Gaborone Declaration for Sustainability in Africa can utilize the spatial findings on connectivity provided by this study to inform future conservation decisions, particularly expanding exiting protected areas.