Elephants and their interactions with people in the Tana river region of Kenya

Abstract

This dissertation describes and evaluates interactions between elephants and people in the 40,000 km2, semi-arid lower Tana River region of eastern Kenya. Traditional forms of land use pastoralism and flood plain agriculture predominated at the time of the study (1974-1976). The region also supported a significant elephant population which had been and currently was being heavily hunted. An understanding of traditional elephant/people interactions was sought, to provide fundamental knowledge for managing elephants and for guiding imminent major development projects. The author takes a holistic approach and examines direct and indirect impacts 'on each other of elephants and people, including their use of and effects on food and water resources, and elephant interactions with agriculture, hunting, pastoral ism, and tourism. The dissertation concludes with recommenda- tions for further research and for application of the methods and information presented, and with brief interpretation of the significance of the iriformation for resource conservation and management issues in the region. A series of four region-wide aerial surveys provided data on elephant numbers and range, seasonal distribution patterns, and the relation of distributions to water availability. Research activities in an intensive study area in the elephants' dry-season concentration zone near the Tana River included monitoring of elephant abundance, elephant raiding of farms, elephant use of and impact on forests, environmental water balance, and rate of decomposition of elephant carcasses. The techniques used were developed by the author. Information also was gathered by a ground census of dead elephants, discussions with residents, personal observation, and use of aerial photo- graphs for vegetation mapping. Information from historical sources helped determine trends and stable patterns of human land use, farm raiding by elephants, hunting of elephants, the trade in ivory, elephant distribution and habitat use, and distribution of vegetation types. Principal conclusions of the study are: (1) Water availa- bility was the major influence on Tana elephants' seasonal distributions and thereby strongly influenced their interactions with people. (2) Elephant raiding of farms in dry periods was the major negative impact of Tana elephants on people; however, its effects were variable and it was not usually the principal limitation on crop production. (3) Ilegal killing of Tana elephants for ivory was a major negative impact of people and probably was causing a marked decline in elephant numbers. (4) Tana River flood plain forests were important to elephants and were rapidly decreasing in area; destruction by people was thought to be the principal cause; preliminary work detected no serious impact by elephants.