On the ecology of the fauna of stones in the current in a South African river supporting a very large simulium (Diptera) population

Abstract

There is a large population of Simulium chutteri lewis in the Vaal river at and below the village of Warrenton in the north-east of the Cape Province, South Africa. The female of this species attacks man, cattle and horses and had become a pest when the studies described here were made. The first aim of this work was to record the density of the Simulium larvae and also of the other invertebrate animals in the river at different times of the year from Warrenton down to Barkly West.