Using population parameters to separate fish stocks in the Okavango delta fishery: A preliminary assessment

Abstract

Populations of three cichlid species from the upper and lower Okavango Delta were compared in terms of biological population parameters, in order to investigate whether the fish species of the Delta consist of one continuous, or two or more separate, stocks. Data were collected from the lower Delta and upper Delta using experimental fishing nets to ensure that representative samples were obtained. While no statistical tests for significance were conducted, the results show that the same species between the upper and lower Delta have different biological parameters. Therefore, it is concluded that these observed differences suggest that, for the three investigated species, there are at least two different populations in the Okavango Delta.