The Tana River mangabey has a restricted range of just 60 km of the Tana River (10), and a highly fragmented population that is in continuing decline due to rapid habitat destruction (1). Without urgent action, there is a high probability of this mangabey becoming extinct over the next 50 - 100 years (11). In 1994 it was estimated that just 1,000 to 1,200 individuals remained (1). The population is possibly much lower today, since their habitat has been severely degraded since then, with an approximate 30 % loss of original vegetation (10) (12). In addition, local communities continue to degrade the remaining forest for products used in the construction of homes and canoes, the collection of wild honey and the topping of date palms to make palm wine (12). As the average number of mangabey groups has been found to correlate with forest area and density of trees, the loss and degradation of forest is a major cause for concern. Mangabey-human conflict has also increased in recent years due to crop-raiding, resulting in traps being set (1).