Distribution and Ecology of the Drill in Cameroon

Drills are among the most endangered primate species in Africa and probably the largest monkey species in the world. They exist only in southwestern Cameroon, a very small portion of extreme eastern Nigeria, and as a very small population on the island of Bioko (Equatorial Guinea) off the coast of Cameroon. As a result of this naturally restricted distribution, and the ever increasing land pressure on their natural range in Cameroon (which is thought to encompass more than 75 percent of the remaining individuals), drills are in dire need of long-term projects to protect their environment and understand their natural history. CRES has been conducting research and conservation on drills in Cameroon since 2002, and during this time has amassed a body of information on this elusive species.

In the Ebo Forest, CRES staff is able to observe wild drills on a weekly basis. They now have a good idea of drill diet, and although this varies enormously throughout the year, fruit is a consistent component, with a vast array of different fruit species being taken. In Ebo, drills seem particularly partial to insects—ants are a favorite—and by looking at fecal remains with a microscope it is possible to identify intact dragonfly eyes.

Drills often travel through the forest in extremely large and spread-out groups, often numbering well over 100 individuals. The dense forested environment, however, increases the difficulty in achieving a good estimation of numbers, and the extremely large ranging patterns of drills makes it difficult to predict where they are in the forest at any certain time of year. That said, by involving ex-hunters from communities surrounding the Ebo Forest we are now able to predict with a moderate degree of certainly the position of the largest groups during any particular month. Recent advances in genetic research allow researchers to venture into identification and sampling of populations by simply collecting their fecal remains without ever having to see drills.. It is hoped that this will eventually lead to gaining a much better idea of group composition and dynamics which will allow a better understanding of their biological needs and hence, conservation strategies.

Drill surveys have been conducted throughout their range in Cameroon since 2002 thanks to key support from the Margot Marsh Biodiversity Foundation. Researchers are now able to say which forests retain significant drill populations, which have lost drill populations in the recent past, and which have drill populations that are likely to disappear in the coming years unless urgent conservation action is taken. By disseminating this information in 2008, researchers hope to engender support for this most spectacular of primate species.

More

News Archives: CRES Researcher Conducts Education Workshop for African Hunters in Effort to Curb Bushmeat Crisis
Educational Outreach Activities Undertaken by CRES in Cameroon
Genetic Work in Cameroon
Conservation Education and the Commercial Trade in Bushmeat

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