POPULATION STATUS, DISTRIBUTION AND TRENDS OF AFRICAN ELEPHANT (Loxodonta africana, Blumenbach 1797) IN NIMULE NATIONAL PARK, SOUTH SUDAN

Abstract

The elephant population in Nimule National Park (NNP) underwent a serious decline in the mid 1990s as a result of poaching for ivory. The study was therefore carried out in NNP and its surrounding buffer zone, in Magwi County of Eastern Equatoria State in South Sudan between January and April 2010. The objectives of the study were: to determine the population size and distribution of elephants in NNP; to determine the trend in elephant population in NNP between 2000 and 2010; and to determine the age structure and sex ratio of elephants in NNP. A systematic random sampling design using line transect method was used to gather data on the status and distribution of the African elephant (Loxodonta africana) in NNP and buffer zone. A comparative population time trend analysis was used to determine elephant population trend. Data on age and sex structure of elephant population were obtained using visual assessment method through direct observation. Results showed that the study area had a total elephant population of 295. The distribution of elephant was not dependent on the types of vegetation within NNP (χ2 = 4.96, df =2, p=0.161). The elephant population showed a significant increasing trend (χ2 = 85.39, df =2; p=0.000) between 2000 and 2010. The age structure of the elephant population was unstable with a significantly lower numbers of young as compared to adults (χ2 = 42.48; df =3, p=0.000). The sex ratio of male to female elephants showed no significant difference (χ2 = 0.0898; df =1, p=0.764) among different age categories in the population. It is concluded that the population changed from 125 to 295 elephants between 2004 and 2010, indicating that mortality factors are becoming less severe. However, the low recruitment rate of young elephants in the population is a cause for worry. It is recommended that further studies be carried out to determine the overall ranging pattern of elephants in the whole Nimule ecosystem covering both dry and wet seasons.