Abstract Observations of drawing behaviour in chimpanzees have often focused on the completed drawings. Here, we compared drawing behaviour using fingers or tools on a touch-sensitive monitor between five chimpanzees from the Kumamoto Sanctuary (KS) and two from the Primate Research Institute (PRI), both located at Kyoto University, Japan. Regarding drawing duration, both PRI females drew relatively longer than the other, with the exception of one KS female. However, a long drawing duration did not correspond with a decrease in the number of pauses, which can be interpreted as a lack of concentration or interest. Therefore, to better understand the engagement of individuals, we recorded the time spent looking at the touchscreen. Pan, one of the two PRI females, had the longest drawing periods and spent the most time looking at the screen. We compared her with Ai, the other PRI female, to better understand their individual marking techniques and behaviours. By adapting to each one’s specific behaviour and previous experience with tool-assisted drawing on paper, we offered the females appropriate tools for making marks on the touchscreen. Our results indicate that electronic devices are not limiting in the expression of drawing behaviour. The females did not have the same drawing technique and also showed different types of engagement as motivation, which could not have been detected by only studying the completed drawings. By focusing more on the process rather than on the drawings themselves, we try to show inter-individual differences in drawing behaviour of chimpanzees and the relevance to adapt to it as experimenters.

Abstract Brazil is known as a high biodiversity country, but at the same time, it has an extensive road network that threatens its wildlife and ecosystems. The impacts of roads and railways on vertebrates have been documented extensively, and the discussion concerning the implementation of mitigation measures for terrestrial wildlife has increased in the last decade. Arboreal animals are especially affected by the direct loss of individuals due to animal-vehicle collisions and by the barrier effect, because most arboreal species, especially the strictly arboreal ones, avoid going down to the ground to move across the landscape. Here we summarize and review information on existing canopy bridges across Brazil, considering artificial and natural canopy bridge initiatives implemented mainly on road and railway projects. A total of 151 canopy bridges were identified across the country, 112 of which are human-made structures of different materials, while the remaining 39 are natural canopy bridges. We found canopy bridges in three of the six biomes, with higher numbers in the Atlantic Forest and Amazon, the most forested biomes. Most of the canopy bridges are in protected areas (76%) and primates are the most common target taxa for canopy bridge implementation. Our study is the first biogeographic mapping and review of canopy bridges for arboreal wildlife conservation in a megadiverse country. We synthesize the available knowledge concerning canopy bridges in Brazil and highlight gaps that should be addressed by future research and monitoring projects.

Abstract Latrine behaviour in lemurs has been interpreted as a means of olfactory communication linked to energy efficient resource defence against neighbouring individuals and/or social bonding within social groups. For social bonding, latrines might best be placed at the core of home ranges, while resource defence could be based on defending the most important part of the home range, i.e., the core area or by establishing olfactory landmarks at the periphery of the home range. Most studies on lemurs describe deposition of urine and faeces in latrines in the core of the home range. In a study at the limit of the distributional range of Lepilemur petteri, at a site with unpredictable weather conditions, we radio-tracked 12 individuals and located latrines within their home ranges. In our study, latrines were located at the periphery of the home ranges. This is interpreted as a means to defend a larger area rather than specific resource rich sites that may or may not provide food in a given year. Regardless of the flexible spatial pattern, and in common with other mammals, lemur latrines are characterized by conspicuous trees, even though urine and faeces are deposited at the base of trees. This indicates some kind of optimal structure of latrines to convey information most effectively, possibly by combining visual and olfactory cues.

Abstract Rivers are important components of animal habitats worldwide. The area near riparian edge (⩽100 m from the river) has different abiotic characteristics and vegetation than both forest interior and areas bordering human development, which may lead to differences in animal feeding behaviour. To better contextualize the impact of human-caused habitat destruction on animal feeding ecology, it is important to study both natural riparian and anthropogenic forest edges within the same habitat. We compared howler monkey (Alouatta palliata) feeding behaviour and tree use across four forest zones (riparian edge, anthropogenic edge, forest interior, and combined riparian and anthropogenic edge) in a fragmented riparian rainforest in Costa Rica, La Suerte Biological Research Station (LSBRS). We predicted that monkey feeding behaviour and tree use would differ across forest zones, and especially between riparian and anthropogenic edges due to higher vegetation quality near the river. We observed individual focal monkeys for 30-minute periods, collecting data on monkey feeding behaviour and tree use every 2 minutes. We recorded plant parts eaten and feeding tree taxonomy, and measured feeding trees. Monkeys ate more leaves in riparian edge than in other forest zones, and fed from fewer tree families in riparian edge and forest interior compared to anthropogenic edge. Monkeys also fed from trees with smaller DBH in riparian edge compared to other forest zones, but trees of similar height to forest interior and taller than anthropogenic edge. Our results indicate that riparian zones are rich habitats for howler monkeys and conservation efforts should prioritize their preservation.

Abstract This paper reports the social-cultural findings from building an artificial canopy bridge for mantled howler monkeys (Alouatta palliata) and other arboreal mammals in Puerto Viejo, Costa Rica. We analyzed participatory observation results from participatory designing and building, and camera trap data from monitoring the bridge. This article also discusses how local perceptions towards monkeys, regional developments, and bridge functions inform primate conservation in that region. It examines a broader primate conservation strategy that addresses entangled values and bridge design in a human-centered, peri-urban, and coastal evergreen forest. We found that artificial canopy bridge design is a complex problem related to humans and targeted species. Connecting habitat with artificial canopy bridges in this context is part of a more significant urban planning problem. Bridge material and design are related to animal usage and existing infrastructure and can shape public views that build or jeopardize public trust.

Abstract Linear infrastructures, especially roads, affect the integrity of natural habitats worldwide. Roads act as a barrier to animal movement, cause mortality, decrease gene flow and increase the probability of local extinctions, particularly for arboreal species. Arboreal wildlife bridges increase connectivity of fragmented forests by allowing wildlife to safely traverse roads. However, the majority of studies about such infrastructure are from Australia, while information on lowland tropical rainforest systems in Meso and South America remains sparse. To better facilitate potential movement between forest areas for the arboreal wildlife community of Costa Rica’s Osa Peninsula, we installed and monitored the early use of 12 arboreal wildlife bridges of three different designs (single rope, double rope, and ladder bridges). We show that during the first 6 months of monitoring via camera traps, 7 of the 12 bridges were used, and all bridge designs experienced wildlife activity (mammals crossing and birds perching). A total of 5 mammal species crossing and 3 bird species perching were observed. In addition to preliminary results of wildlife usage, we also provide technical information on the bridge site selection process, bridge construction steps, installation time, and overall associated costs of each design. Finally, we highlight aspects to be tested in the future, including additional bridge designs, monitoring approaches, and the use of wildlife attractants.

Abstract Roads negatively affect wildlife populations globally, causing habitat fragmentation that can facilitate mortality by access to forest for poaching and wildlife collisions with vehicles. Primate habitats are vulnerable to fragmentation exposing them to anthropogenic threats. Endangered dusky langurs (Trachypithecus obscurus) in Malaysia are often found in urban areas and have been frequent victims of vehicle collisions. To mitigate the hazardous impact of a busy asphalt road on wild dusky langurs in Teluk Bahang, Penang, we built the first artificial road canopy bridge in Malaysia in February 2019 to assist arboreal wildlife to move between habitat fragments more safely. Four days after the bridge construction, the first long-tailed macaque (Macaca fascicularis) was recorded via a camera trap crossing the bridge, and plantain squirrels (Callosciurus notatus) and dusky langurs first crossed one and eight months later, respectively. The bridge was upgraded from a single-firehose rope to a double-rope in August 2020 to assess the effectiveness of the two designs. In total, 2128 animal crossings comprising three mammal species were recorded between March 2019 and May 2021. Plantain squirrels crossed the bridge most frequently with 2075 crossings, long-tailed macaques crossed 32 times, and dusky langurs 21 times. There was a significant difference in bridge use according to species between the two designs (Chi-Square, p < 0.001). Since the construction of the bridge, the rate of previously frequently reported primate roadkills near the bridge location has dropped to zero. This successful pilot project has spurred the efforts to implement more canopy bridges country-wide to support primate conservation efforts and better protect arboreal wildlife from the negative impacts of linear infrastructure.

Many investigators of human-monkey competition (HMC) in Sri Lanka have revealed some common threads. Except at temple and protected sites, all monkeys were considered as household or agricultural pests wherever they shared space with humans. This included the widely distributed toque macaque (Macaca sinica), the grey langur (Semnopithecus priam thersites) of the Dry Zone, and the purple-faced langur (S. vetulus) of the southwestern and central rain forests where human densities and habitat fragmentation were greatest. People sharing space with monkeys resorted to various non-lethal methods to chase monkeys away from their properties and most preferred to have monkeys removed to protected areas; such translocations have been politically popular, though contrary to ecological principles. The main cause of HMC near primate habitats has been environmental conversion to agriculture, whereas in many towns the refuse generated in the wake of widespread growing tourism lured omnivorous macaques towards human habitation and stimulated macaque population growth. While most Sri Lankans share space with monkeys reluctantly, only a minority, flouting cultural restraints, want monkeys destroyed. Nonetheless, a major threat to primate conservation has been habitat loss and the killing of monkeys, especially in the densely populated southwestern area of the island where recent surveys showed that most macaques have been wiped out. Two subspecies, S. v. nestor of the rain forest lowlands and M. s. opisthomelas of the montane forests, are Critically Endangered. Sharing space with monkeys rests on public tolerance, understanding, and empathy with monkeys. Religious concepts venerating monkeys provide fertile ground for this. Our science-based educational documentaries (n > 35), among other efforts, also have contributed to these human sentiments in Sri Lanka and globally. The trends in HMC suggest that protected nature reserves for all wildlife are more secure for primate survival than ethnoprimatology by itself would be. Rudran [Folia Primatologica 2021, DOI: 10.1159/000517176] criticized our recent publication on HMC in Sri Lanka [Dittus et al., Folia Primatologica 2019, 90: 89–108]. We consider his comments as misconstruing efforts in primate conservation through denying the importance of traditional protected areas, overlooking our achievements in educating the public and reducing HMC, as well as misunderstanding the limits of marketing monkeys to tourists as a source of income to support conservation.