Ecology, conservation and management of the black lechwe (Kobus leche smithemani) in the Bangweulu Basin, Zambia

Abstract

The black lechwe Kobus leche smithemani) is an antelope that belongs to the family reduncinae. Its current population is confined to the Bangweulu Basin in the northern Zambia. This research was undertaken to assess its current population status, the sex and age ratios, carrying capacity of the flood-plain where it occurs and its maximum sustainable yield. The study also estimated its potential sustainable off-take and looked into the links that exists between wildlife and socio-economics in order to demonstrate the views of local people on current wildlife management and utilisation. Historical records suggest that these antelopes were more widely spread and more numerous earlier last century. Until the 1930s the population may have numbered over 250 000. Records indicate major population decline during the first half of last century and therefore called for a quick management action. The population decline was thought to be caused by over-hunting and habitat change caused by an increase in water levels in the swamps. Aerial surveys during the 1950s suggested less than 20000 and by 1970 only 16 000 lechwe were counted from the air. From 1988-1996, ground surveys were undertaken with a four-wheel drive vehicle, on motor bike and on foot. A series of aerial censuses was also conducted during October, at the height of the dry season when the lechwe are relatively evenly distributed in the swamps, thus facilitating the use of stratified random sampling method. A fixed wing cessina 182 was used throughout the surveys. The study revealed that black lechwe is a highly prolific and resilient species. Its population has great potential to increase if given adequate protection and proper managed. Mating takes place on shallow flood-plains between November and April, but peaks in March. Receptive females leave their herds to join small breeding ground comprising few dominant males, which may be likened to leks formed by some other antelopes. The population of lechwe is currently maintained around 30,000. The sex ratio of the species is equal to unity and the age ratio was estimated at 3 : 1. The entire Bangweulu wetlands can sustain a population of at least 160 000 lechwe. A sustainable off-take of 6 000 individuals per annum was recommended. Black lechwe being an endemic species to the Bangweulu Basin is important for the economy of the country and the rural population. The study has revealed that local people are keen to participate in conserving it together with other species and the habitat as long as they are clear about benefits that they will gain from their effort.