Early life history of Pomatomus saltatrix off the east coast of South Africa

Several authors have stated that southward transport of the early life-history stages of Pomatomus saltatrix occurs by passive drift in the Agulhas Current, a strong western boundary current which flows southwards following the edge of the continental shelf of eastern South Africa. However, an extensive study of the ichthyoplankton occurring in shelf and Agulhas Current waters from 29 degrees S to 34 degrees S located P. saltatrix larvae only in the shelf waters off KwaZulu-Natal. Sampling of fish eggs in the inshore shelf waters 60 km south of Durban on a regular basis has confirmed spawning of P. saltatrix to occur in this region. The data thus suggest that larval dispersal might occur in shelf waters where, although strongly influenced by the Agulhas Current, southward transport is not as rapid.