Using hotspot analysis to track changes in the crustacean fishery off KwaZulu-Natal, South Africa

Abstract

This study focuses on the KwaZulu-Natal deepwater crustacean trawl fishery located off the east coast of South Africa. It investigates the spatiotemporal changes in fishing effort and catch per unit effort of three target species of knife prawns (Haliporoides triarthrus), African langoustine (Metanephrops mozambicus) and pink geryon (Chaceon macphersoni) using a space–time cube and hotspot analysis in ArcGIS Pro. This analysis shows the contraction of the fishing effort over time and the confining of the most productive localities to a relatively small area directly off the vessels’ home port of Durban. This provides invaluable information on a fishery that has not been subjected to any formal stock assessments and hopefully inspires other countries in the western Indian Ocean with similar data limitations to produce their own analyses of their trawl grounds.