Camera traps unveil demography, social structure, and home range of six unhabituated Western chimpanzee groups in the Moyen Bafing National Park, Guinea.

Precise estimates of population dynamics and social grouping patterns are required for effective conservation of wild animal populations. It is difficult to obtain such information on non-human great apes as they have slow reproductive rates. To gain a better understanding of demography in these populations, previous research has typically involved habituation\, a process that requires years. Here, we collected data continuously over year-long periods to monitor an unhabituated population of critically endangered Western chimpanzees (Pan troglodytes verus) in the Moyen Bafing National Park, Guinea. We used two arrays of 100 camera traps that were placed opportunistically in two distinct 100 km2 sites, named Bakoun and Koukoutamba. We identified 227 individuals in Bakoun and 207 in Koukoutamba through their unique facial features. Our camera trap data make clear that these individuals belong to six and seven closed groups, respectively. Six of those groups were near-completely sampled with an average minimum size of 46.8 individuals (range: 37-58), and a mean adult sex ratio of 1.32 (range: 0.93-2.10). We described the demographic composition of these groups and use Bayesian social network analysis to understand population structure. The network analyses suggested that the social bonds within the two populations were structured by sex homophily, with male chimpanzees being more or equally likely to be observed together than other adult associations. Through estimation of minimum convex polygons, we described the minimum home range for those groups. Compared to other chimpanzee groups living in a similar environment (mosaic savanna-forest), the Moyen Bafing region seems to host a high-density of chimpanzees with small home ranges for their group size. Our research highlights the potential of camera traps for studying the demographic composition of chimpanzee populations with high resolution and obtaining crucial information on several groups in a time-efficient and cost-effective way.

Chimpanzee identification and social network construction through an online citizen science platform.

Citizen science has grown rapidly in popularity in recent years due to its potential to educate and engage the public while providing a means to address a myriad of scientific questions. However, the rise in popularity of citizen science has also been accompanied by concerns about the quality of data emerging from citizen science research projects. We assessed data quality in the online citizen scientist platform Chimp&See, which hosts camera trap videos of chimpanzees (Pan troglodytes) and other species across Equatorial Africa. In particular, we compared detection and identification of individual chimpanzees by citizen scientists with that of experts with years of experience studying those chimpanzees. We found that citizen scientists typically detected the same number of individual chimpanzees as experts, but assigned far fewer identifications (IDs) to those individuals. Those IDs assigned, however, were nearly always in agreement with the IDs provided by experts. We applied the data sets of citizen scientists and experts by constructing social networks from each. We found that both social networks were relatively robust and shared a similar structure, as well as having positively correlated individual network positions. Our findings demonstrate that, although citizen scientists produced a smaller data set based on fewer confirmed IDs, the data strongly reflect expert classifications and can be used for meaningful assessments of group structure and dynamics. This approach expands opportunities for social research and conservation monitoring in great apes and many other individually identifiable species.

Anticonvulsant hypersensitivity syndrome with fatal outcome.

Anticonvulsant hypersensitivity syndrome is a disease characterized by multisystemic involvement, fever, lymphadenopathy, mucocutaneous rash, hypertransaminasemia and peripheral eosinophilia. This rare syndrome seems to be related to arene oxide metabolites of aromatic anticonvulsants (phenytoin, phenobarbital and carbamazepine). Anticonvulsant hypersensitivity seems to be much more aggressive in patients undergoing concomitant radiotherapy. We report a case of anticonvulsant hypersensitivity syndrome developing toxic epidermal necrolysis with fatal outcome in a patient receiving cranial irradiation and aromatic anticonvulsants for seizure prophylaxis. This report attempts to emphasize the importance of an early diagnosis of this syndrome, the knowledge of the common cross-reactivity among the major anticonvulsants and the need for an appropriate measurement of the true benefits of seizure prophylaxis in patients with brain tumors.