A Reassessment of the Population Size, Demography, and Status of Tanzania’s Endemic Kipunji Rungwecebus kipunji 13 Years on: Demonstrating Conservation Success

• Published in: International journal of primatology Vol. 43; no. 2; pp. 317 - 338
• Main Authors: Davenport, Tim R. B., Machaga, Sophy J., Mpunga, Noah E., Kimiti, Sylvanos P., Mwalwengele, Willy, Mwaipungu, Obadia, Makumbule, Pascal M.
• Format: Journal Article
• Language: English
• Published: New York Springer US 01.04.2022; Springer Nature B.V
• Subjects: Adults; Animal Ecology; Animal Genetics and Genomics; Anthropology; Biomedical and Life Sciences; Censuses; Charcoal; Conservation; Demography; Endangered; Endangered species; Evolutionary Biology; Females; Group size; Human Genetics; Life Sciences; Males; Men; National parks; Nature reserves; Occupancy; Population number; Spatial data; Wildlife conservation; Zoology; Tanzania; Primates; Census; Endangered; Conservation; Tanzania
• ISSN: 0164-0291; 1573-8604
• DOI: 10.1007/s10764-022-00281-3

Long-term population data on endangered species are fundamental to measure conservation implementation objectively, but they are rare, especially in remote forest locations and with total counts. Following the scientific description of the kipunji ( Rungwecebus kipunji ), we implemented a range of long-term conservation interventions. Thirteen years later, we reassess with a complete count the population size, demography, and distribution of R. kipunji in Tanzania’s Southern Highlands, employing the identical sweep census methods across 1,428 km. We also monitored a habituated group daily over the same period. We report a total of 1,866 individuals in 59 groups ( μ = 31.63 ± SE 1.2) in Livingstone Forest (within Kitulo National Park), Mt Rungwe Nature Reserve, and Madehani Village Forest. We estimate a 65% increase in individuals, a 59% increase in group numbers, and a 19% increase in area of occupancy (AoO). Mean group sizes were similar in Mt Rungwe (32.9) and Livingstone (31.9), but lower in the unprotected Madehani (24). The ratio of adult females to adult males was significantly higher in Mt Rungwe than Livingstone. The ratio of subadults/juveniles to adult females, a proxy for survival, was good (1.77), but higher in Livingstone (2.61) than Mt Rungwe (1.11). In the habituated group, we recorded a 121% increase in group size. Signs of human activity fell by 81%, with a 100% and 98% reduction in the number of charcoal pits and timber felling, respectively, in Mt Rungwe. Both temporal and spatial data demonstrate that long-term holistic conservation leads to increased primate numbers.