Environmental Conservation


Benefits and costs of illegal grazing and hunting in the Serengeti ecosystem

J.W. NYAHONGO a1, M.L. EAST a2c1, F.A. MTURI a3 and H. HOFER a2
a1 Tanzania Wildlife Research Institute, PO Box 661, Arusha, Tanzania
a2 Leibniz-Institute for Zoo and Wildlife Research, Alfred-Kowalke-Strasse 17, D-10315 Berlin, Germany
a3 Department of Zoology and Marine Biology, University of Dar es Salaam, PO Box 35091, Dar es Salaam, Tanzania

Article author query
nyahongo jw   [PubMed][Google Scholar] 
east ml   [PubMed][Google Scholar] 
mturi fa   [PubMed][Google Scholar] 
hofer h   [PubMed][Google Scholar] 


Two forms of natural resource use (meat hunting and livestock grazing) were investigated at three sites in the western region of the Serengeti ecosystem, Tanzania. Statutory management of natural resources in this region was designated as National Park, Game Reserve or village council. A quasi-experimental design examined factors likely to alter the cost and benefit of illegal use by ranking areas within sites in relation to these factors. Factors likely to alter costs were the chance of arrest, determined by the presence or absence of guard posts, and the distance travelled to the site of exploitation. As all sites experienced large fluctuations in the density of migratory herbivores, it was assumed that the benefit acquired from hunting increased with wild herbivore density. Marked seasonal changes in precipitation were considered likely to alter the value of forage and water to livestock owners. Hunting effort (density of snares) increased as the density of wild herbivores increased. The distribution of hunting effort across sites was more consistent with the prediction that high travel costs were more likely to curtail hunting than a high potential cost of arrest. Unlike hunters, livestock owners mostly avoided the use of resources in protected areas probably because of the high potential cost of arrest and confiscation of stock. Natural resources within protected areas were exploited when benefits outweighed likely costs.

(Received December 10 2004)
(Accepted January 11 2006)

Key Words: illegal hunting; livestock grazing; natural resources; Serengeti ecosystem.

c1 Correspondence: Dr Marion L. East Tel: +49 30 5168512 Fax: +49 30 5168735 e-mail: east@izw-berlin.de