Impact of dam construction on two elephant populations in northern Cameroon

Abstract

Construction of dams in northern Cameroon, the Maga Dam in the vicinity of Waza NP in 1979 and the Ladgo Dam in the vicinity of Bouba-Ndjidda, Benoue and Faro NPs in 1980 had profound effects on elephant populations in the northern Cameroon. The elephant populations in both areas increased rather dramatically and increased crop raiding has been a pattern in both areas. This article reviews data from 1994-2002 studies, focused on seasonal movement of the elephants and crop raiding problems. In 1978 the dry season elephant population in Waza NP was estimated at 465 animals, in 2001 the estimation was 1140. In the Lagdo area there were no elephants resident during the dry season prior to construction of the dam - twenty years later, in 2000 about 250-300 animals are in the area. The Waza elephant have undergone more scrutiny as they have been studied since 1986, but the Ladgo population has been observed only since 1995. 3 adults in each area (3 cows in Waza 1993,1994 and 1996: 1bull and 2 cows in Ladgo 2000) were radio collared in order to study movement, home range and habitat use by the subpopulations. Data suggest the home range of the Waza populations to be about 2546 sq kms while that of those in the Ladgo area is significantly less, about 119 sq kms. Dam construction in in the Waza area resulted in severe deterioration of the perennial floodplain vegetation between 1980-1994, and the Waza elephants showed seasonal migration to an area over 100 km south of the Park where they caused significant crop damage. After the floodplain was artificially reflooded in 1994 they did not alter this pattern of movement, but shifted their dry season habitat in the park from the Acacia savannah zone to the floodplain. The Ladgo elephant have consistently spend more time in the floodplain area, as their habitat did not deteriorate after the dam was constructed. (Saleh, et al., 2002. de Iongh, et al, 1999). This article was given aa a paper 'Impact of dam construction on two elephant populations in Northern Cameroon' at the 6th AfESG meeting at Mokuti Lodge, Namibia, 4-8 December 2003.