Challenges and possible impacts of artisanal and recreational fisheries on tigerfish Hydrocynus vittatus Castelnau 1861 populations in Lake Kariba, Zimbabwe

Abstract

Increased fishing pressure from artisanal and recreational fishing has led to the collapse of some important fish stocks around the world over the past years. There is currently limited understanding of the impacts of recreational and artisanal fishing on tigerfish Hydrocynus vittatus populations in Lake Kariba and the socioeconomic factors behind them. Hence, this study investigated socioeconomic factors that act as drivers of the recreational and artisanal fishery industry and what sort of impact this would likely have on tigerfish H. vittatus populations using qualitative approaches. Eight three percent of the artisanal fishers interviewed recorded high catches during the summer season (October–February), which also coincides with the breeding season for tigerfish when it migrates up the rivers. Recreational anglers mainly caught females during the tigerfish tournament which is likely to have a significant effect on the tigerfish population in the long term through changes in tigerfish recruitment and other life history traits. Tigerfish size at sexual maturity and catch per unit effort which are all indicators of overexploitation were found to have decreased over the past years. Results further demonstrated increased fishing activities from artisanal and recreational fishing. It can be implied that the population of tigerfish may inadvertently be affected, but direct evidence that both recreational and artisanal fishing were having impacts on tigerfish populations was limited. It is therefore recommended that effective conservation measures such as preventing fish poaching during the tigerfish breeding season are put in place to protect the population and that of other fishes (i.e. potential prey).

Keywords

• Lake Kariba
• Tigerfish
• Breeding season
• Fishing tournament
• Hydrocynus vittatus
• Socioeconomic factors