MODELING PENAEID PRAWN LARVAL ADVECTION IN ALBATROSS BAY, AUSTRALIA -DEFINING THE EFFECTIVE SPAWNING POPULATION

A 3-dimensional numerical circulation model was linked to four larval- postlarval behaviour patterns to establish the origins of postlarvae r ecruiting into the estuaries adjacent to Albatross Bay, Gulf of Carpen taria, Australia. The area from which these postlarvae originate is ca lled the 'advective envelope' and it delimits the spatial extent of th e effective spawning population. The different behaviour scenarios var y the amount of time the postlarvae are active during the flood tide a nd the depth at which they change between their diel and tidal activit y patterns (transition depth). The envelope with a behaviour scenario that incorporated a 20 m transition depth and a 3 h tidal activity pat tern was 1000 km(2). Incorporation of seasonal winds changed the shape but not the extent of the advective envelopes.