The Primate Monitoring Programme is the longest-standing ecological monitoring effort in the Udzungwa Mountains, with uninterrupted activity spanning more than twenty years. The programme follows a standardized protocol consisting of systematic surveys conducted along four permanent transects, measuring between 3.6 and 4 km, located in different places of the Udzungwa Mountains. Each month, a trained observer accompanied by an assistant completes the surveys.
Five primate species are consistently included in the monitoring scheme:
- Udzungwa red colobus (Procolobus gordonorum, endangered and endemic)
- Peters’ Angola colobus (Colobus angolensis)
- Tanzania Sykes’ monkey (Cercopithecus mitis monoides)
- Sanje mangabey (Cercocebus sanjei, endangered and endemic)
- yellow baboon (Papio cynocephalus)
During these slow-paced transect walks, all primate encounters are carefully documented. The programme has provided
vital insights into the status of key species, including endemic and endangered primates, population trends, habitat use, and changes over time. The data reveal important differences across protected areas, reflecting varying levels of human pressure and conservation effectiveness.
This long-term approach highlights both challenges and recovery potential. By linking monitoring data with on-the-ground protection efforts, we support more targeted conservation actions and rapid responses to emerging threats.
Complementary research on primate health further deepens our understanding, using indicators such as microbiota to assess how environmental conditions influence wildlife wellbeing.