Fisheries & Aquaculture

Portia Chiyedza Chifamba has keen interest in Fish and Fisheries Biology. Her work includes studies of diet and growth of several fish species. She has undertaken extensive studies of two fish species introduced into Lake Kariba; Nile tilapia, Oreochromis niloticus and freshwater sardine, Limnothrissa miodon. The studies demonstrate that unplanned introduction of Nile tilapia had negative impact on the ecosystem compared to planned introduction of the sardine intended to fill a vacant niche and improve fish production. She has compared the diet, aggression, reproductive capacity and growth of the Nile tilapia in order to determine the traits that might have given the introduced species competitive advantage over the endemic indigenous cichlid, Oreochromis mortimeri. The fisheries work she has undertaken includes establishing that effective fishing effort in the sardine fishery and it increases as a result of fishing vessel and gear improvement, an aspect critical in the management of fishing effort.