ADULT MOVEMENT AND LARVAL DISPERSAL OF ARGYROZONA ARGYROZONA (PISCES: SPARIDAE) FROM A TEMPERATE MARINE PROTECTED AREA

Abstract

Adult emigration and larval dispersal of carpenter Argyrozona argyrozona from the Tsitsikamma National Park (TNP), South Africa, were investigated using mark-recapture data and Acoustic Doppler Current Profiler measurements of currents. Tagging data showed that adult carpenter were mainly resident, with a small proportion (7%) leaving the TNP in both easterly and westerly directions. There was no relationship between fish movement patterns and fish size or time-at-liberty. Current patterns suggest that eggs and larvae spawned within the TNP are mainly transported eastwards towards established nursery grounds; the median estimated distance moved was 299 km (range 42–561 km) in 30 days (time to flexion). Given this pattern of ichthyoplankton dispersal, together with the fact that adult carpenter within the TNP displayed a high degree of residency and that they are much more abundant than in adjacent fishing grounds (catch per unit effort being 23 times greater), it appears that the TNP protects a viable carpenter spawner population capable of seeding adjacent fishing grounds.