The ichthyofauna associated with Zostera capensis Setchell in the Swartkops estuary, South Africa

Abstract

The ichthyofauna associated with Zostera beds in the lower reaches of the Swartkops estuary was examined by means of haul seine netting over 15 months. Thirty-nine fish species were caught in the Zostera beds and the small shoaling species, Hepsetis hreviceps and Gilchrlstella aestuarlus, constituted 55% of the total catch in terms of numbers. Juveniles of six mullet species occurred in the Zostera and recruitment took place throughout the year. Sparids such as Rhabdosargus holubi and Dlplodus sargus showed marked spring and summer recruitment. The recruitment patterns of Juveniles to the Zostera beds is correlated with documented breeding cycles of adults, particularly those breeding in the shallow inshore marine environment. The Swartkops Zostera beds were found to form an integral and important part of the nursery function of the estuary.