Threatened Endemic Fishes in South Africa's Cape Floristic Region: A New Beginning for the Rondegat River

Abstract

ABSTRACTNonnative fishes threaten native fish communities in many rivers of the world. In South Africa's Cape Floristic Region, predation by nonnative fishes has severely impacted native fish populations and more than half of the 17 endemic fish species are endangered. To preserve the unique endemic fish fauna, removal of nonnative fish from conservation areas is a priority in this region. In February 2012, South Africa's first nonnative fish eradication using rotenone took place in the Rondegat River, a small headwater stream that had been invaded by Smallmouth Bass (Micropterus dolomieu). The successful treatment culminated from a decade‐long process that was facilitated through collaboration among a South African nature conservation authority (CapeNature), the South African Institute for Aquatic Biodiversity, and the American Fisheries Society Fish Management Chemicals Subcommittee. The successful removal of alien fish and almost instantaneous increase in biodiversity is anticipated to encourage more endemic fish restorations in South Africa.