The macroinvertebrates of a polluted stream in Ghana

There is a limited understanding of the lotic macroinvertebrate fauna of We st Africa, although many watercourses are heavily impacted. Macroinvertebra tes were sampled from a stream running through Accra, the capital of Ghana, to provide information on the nature of these communities and their respon se to pollution. The physicochemical pollution gradient in the stream was r eflected in the macroinvertebrate community, which showed a similar respons e to that observed in well studied temperate areas. Heavily polluted sites within the city supported a poor fauna and were dominated by tolerant taxa, such as the Chironomidae. The success of the macroinvertebrate fauna in re vealing the pollution gradient and discriminating between sites suggest tha t there is potential for biological monitoring in such situations.