The zooplankton community of Lake Kariba in 1962/63 following impoundment of the Zambezi River

Abstract

Lake Kariba, bordered by Zambia in the north and Zimbabwe in the south, was formed following the impoundment of the the Zambezi River in 1955. Pre- and post-impoundment studies, which were undertaken on Lake Kariba by the Joint Fisheries Research Organisation of Zambia and Malawi, generated data on the limnology, fish and zooplankton. Fryer identified free-living Crustacea from the flooded backwaters of the Zambezi river. Thomasson, reporting on the algae in the lake, identified zooplankton collected during May and June 1959. This paper coordinates information on the lake basins, the rivers flowing into Lake Kariba, sampling stations and identification of the zooplankton collected in more comprehensive surveys in 1962 and 1963. At this time the zooplankton community in the lake was made up of thermophilic species adapted to survival in the water column. However, some calanoid copepod species were collected, mainly from river estuaries and in shallow areas of the lake, which are related more to their natural habitat. The zooplankton community comprised 10 rotifer species, 16 species of Cladocera, six calanoid and at least six cyclopoid copepod species, three ostracod species, the limnomedusa Limnocnida tanganjicae, a species of Chaoborus, and a few insect larvae. In less than a decade after impoundment of the Zambezi River, the large subtropical Lake Kariba was colonised successfully by a diverse zooplankton community.


Keywords: zooplankton species; Lake Kariba; Zambezi River; subtropical Africa; impoundment


(Afr J Aqua Sci: 2001 26(1): 9-15)