The Macaca Nigra Project: a long-term project on the biology, ecology and conservation of crested macaques in Tangkoko, North Sulawesi, Indonesia

The Macaca Nigra Project is a long-term project on the biology, ecology and conservation of the crested macaques, Macaca nigra. Funded in 2006 in the Nature Reserve of Tangkoko, North Sulawesi, Indonesia, it takes a triple approach, research, conservation and education. Crested macaques are Critically Endangered with a steep decline in population since the publication of the first survey (-80% since 1970). Like all macaques, they live in large social multi-male multi-female multi-generational groups where females are philopatric and males migrate at adulthood. Crested macaques also present outstanding reproductive and social characteristics: within a group, they are socially very tolerant yet have frequent sometimes very aggressive intergroup encounters; males sport long sharp canines, utter dominance-linked loud calls, and display bright red scrotum, indicative of high sexual competition; females are very affiliative with each other, present dense diverse grooming networks and reproduce year-round, on average one single infant every 1.5y. The environment shows near constant minimum and maximum temperature across the year but periods with heavy rainfall. Food is highly seasonal but abundant all-year round. The only predators of consequence are reticulated pythons and humans. We conduct research on reproduction, sociality, communication, cognition, feeding ecology, health, genetics, human-wildlife interactions, or environmental education. We follow 2 to 3 social groups at any one time. Field assistants collect data every day from dawn to dusk on the monkeys’ activities as well as on specific behaviours. They also collect data on climate (temperature, rainfall) and home range (GPS tracks), and they collect fecal samples for genetics, hormonal and microbiome analyses. So far (nov2024), the database contains: behavioural data (activity, agonistic interactions), GPS tracks, and demographical data (sex, date of birth, date of disappearance/death, date of migration). The project is a partnership between academic institutions and local organisations, mainly IPB University (Department of Biology, Primate Center and School of Veterinary Medicine and Biosciences), Bogor, Indonesia, UNSRAT University (Faculty of Forestry), Manado, Indonesia, the University of Portsmouth (Faculty of Psychology), Portsmouth, England, the University of Leipzig (Department of Biology), Leipzig, Germany, the National Center for Scientific Research (CNRS), the National Museum for Natural History (MNHN) (Eco-Anthropology Unit), Paris, France, the Office for the Management of Natural Resources (BKSDA), Manado, Indonesia, and the National Research Agency (BRIN), Jakarta, Indonesia.