Natural ecosystems are severely disrupted by human activities. Our interactions with wildlife are intensifying and promoting zoonosis. Humans and chimpanzees can harbour and transmit pathogens to each other. The aim of this study is to improve our knowledge of the diversity of gastrointestinal parasites in Fongoli chimpanzees. This is a habituated group that has been monitored over the long term and whose members have all been identified. During the period from 22 February to 11 March 2022, we monitored them daily to collect fresh stool samples in a non-invasive manner. A total of 17 individuals were sampled for 39 faeces samples collected and fixed in 10 % formalin. In the laboratory, we performed a coproscopical analysis of the fixed faeces using flotation and sedimentation methods. The parasite diversity included six protozoa (Troglodytella spp., Troglocorys spp., Entamoeba coli, Entamoeba spp., an unidentified ciliate, and Coccidia) and six helminths (Enterobius spp., Strongyloides spp., Dicrocoelium spp., Ascaris spp., Spirurids, and Strongylids). We found protozoa in all individuals and helminths in 70 % of individuals. We found an average of 6 ± 1.41 types of gastrointestinal parasites, including 1.47 ± 1.07 helminths per individual. Chimpanzees in Fongoli harbour a significant diversity of intestinal parasites, some of which are common to humans and have zoonotic potential.
This paper reports long-term data on the seasonality of sightings of Ucayali bald uakaris, Cacajao ucayalii at the Estación Biológica Quebrada Blanco (EBQB). Sightings were most common during the drier parts of the year and rarer during the rainy season. This suggests that the C. ucayalii groups travel long distances and seasonally move (migrate) between different parts of presumably large home ranges and between different habitats (terra firme forest, Amazon floodplain forest). Areas to protect this Neotropical primate must be large enough to allow for sufficient seasonal access to these vegetation types.
Between May 2014 and March 2016, 22 groups of Mount Kenya guerezas (Colobus guereza kikuyuensis Lönnberg, 1912) were reintroduced in Karura Forest, Kenya. To assess the success of the reintroduction, we conducted monthly censuses over 8 years (2016–2023). We determined group size and composition of the reintroduced population. During the censuses, we recorded instances of births, deaths (disappearance), dispersal from natal groups, and the habitat types where groups established home ranges. A total of 14 of the reintroduced groups settled along the riverine zones. Over the years, we recorded an annual increase in the number of births and group size, indicating successful adaptation of the reintroduced primates. Coming from a degraded source habitat, the primary cause of death was related to arboreality adaptation (23 %), and only one case of infanticide during a group takeover was recorded. Group fusion was not observed; however, seven groups with more than two adult males began splitting in 2019. By December 2023, 109 births had been recorded, and groups increased to 31 due to natal dispersal. Our results demonstrate that C. guereza kikuyuensis reintroduction to Karura Forest was a success.
Water is an essential nutrient for living beings and is fundamental to metabolic processes. Under free-living conditions, primate individuals can use different strategies, skills, and resources to access water. Here, we report on observations of water consumption in Ateles chamek and Sapajus apella; describe the environmental conditions in which such events were observed, as well as the behavior of the individuals; and compare these observations with similar records in neotropical primates. Water consumption was observed during primate surveys in a forest fragment of approximately 52 ha bordered by the Jaru River, located southwest of the Brazilian Amazon, Vale do Paraíso municipality, state of Rondônia, Brazil. To access water, individuals of A. chamek used their tails, whereas S. apella used a leaf as a tool. Our observations suggest that tree holes may be important water sources for primates in forest fragments and that individuals of different species use different strategies to collect water from tree holes. Access and consumption strategies are directly associated with different cognitive skills and behaviors, which may include using tools, as in the case of capuchins. As water consumption records are limited, these findings highlight the need for continuous reporting to better understand water acquisition. Such reports are especially needed in the context of fragmented and degraded habitats, where water availability is affected by edge effects and the reduction in both fleshy fruits and moisture, which are important for primate species.
Intersexual dominance relationships in virtually all lemur species have been reported to be female-biased. Although a claim of male dominance in greater bamboo lemurs (Prolemur simus) which was not supported by data is unusual against this background, it is in line with recent studies on other lemur species that suggest the existence of a continuum of intersexual dominance relationships. We therefore studied the details of agonistic interactions among adults of one captive group of P. simus at Cologne Zoo. This very preliminary study confirmed male-biased dominance because the adult male of the study group won all agonistic interactions with all three adult females, and the male was never dominated by any of the females. This result raises several interesting questions about the mechanisms and evolution of intersexual dominance relationships in group-living lemurs and should encourage similar future studies of additional groups of this species – ideally in the wild.
