Visitors to Tacugama have often asked how many wild chimpanzees there are in Sierra Leone and until recently the honest answer was that nobody knew. The last formal estimate was made in 1981 by Teleki and Baldwin who concluded that around 2,000 wild chimpanzees remained in the wild, predominantly in protected forest reserves.
In the fifteen years that Tacugama has been operating we have continued to receive and rehabilitate orphaned chimpanzees from across the country. Almost 30 years since that estimate was made It became increasingly urgent to determine a more accurate number and to confirm where chimpanzees could be found in the wild. We needed to know the real situation so that more effective protection measures could be implemented and the flow of orphans to the sanctuary could be stemmed.
With support from PASA (Pan African Sanctuary Alliance in April 2008 we prepared a proposal for the census, gained approval from the Government of Sierra Leone and raised enough funds to start the initial phases of the project in October 2008. The census fieldwork concluded in May 2010 and preliminary results were released on 1 June 2010. The final report was released in September 2010.
The project has provided much valuable information on the state of habitat, impact of human encroachment and other large mammal species as well as the distribution and abundance of wild chimpanzees in Sierra Leone. The groundbreaking approach has resulted in a systematic and extensive survey.
The final results show that Sierra Leone is home to around 5,500 chimpanzees, double previous estimates. This exciting news gives new hope for the survival of the endangered Western Chimpanzee Pan troglodytes verus but also reveals that there are many threats to the remaining chimps. Over half are living outside of protected areas.
Click here to download the full census report (pdf format)
HOW TO COUNT WILD CHIMPANZEES
Counting chimpanzees across an entire country is a complicated task. Because it is realistically impossible to count every single chimpanzee, some sort of estimate must be made. Chimpanzees may occur in many different habitat types and we are using several different methods, each one according to the type of habitat to be surveyed.
Chimpanzees are difficult to see in the wild so we look for their signs. Signs can include direct sightings, feeding remains, dung, or nests. Nests are the most commonly observed signs. Chimpanzees create a new nest each night to sleep in by bending branches into a solid bowl up in a tree. These can remain visible for up to several months.
A chimp demonstrating his nest at Tacugama - it's not so easy to spot in the wild!|
Click on images to enlarge.
Spotting a wild nest from below (it's the darker spot in the centre of the picture)|
The census report includes a detailed description of the methodology
There is much work now to be done to follow up on the information gathered and Tacugama is already working to promote ownership of conservation at the grassroots level where developing sustainable livelihoods is the challenge among very poor communities.
A key step will be the delivery of a Population and Habitat Viability Assessment workshop in Sierra Leone in early 2011 that will involve key stakeholders and result in the delivery of a realistic chimpanzee conservation action plan.
Delivering the census project has been a major achievement for Tacugama. As the sanctuary marks its 15th Anniversary in 2010 the challenge is to ensure we build on the census results to secure the long term survival of chimpanzees in Sierra Leone.
Census Press release: PDF
Census Report: PDF
The Census Team Team Page
Blog: Wildlife Direct