The utilization of tidal currents by the larvae of an estuarine fish

Abstract

The mechanisms employed by Gilchristella aestuarius larvae to maintain their position in an estuary were investigated in the Sundays River estuary, South Africa. The larvae predominated in the bottom water on both the flood and ebb tides and by so doing, utilized the flood-tide bottom-water current and avoided the ebb-tide surface current, the net result being a transport of the larvae upstream. There was no evidence to suggest that the larvae migrate laterally toward favourable, or away from unfavourable, currents.