This research is examining the
relationships between larval supply, settlement and
recruitment of two commercially important decapod
crustaceans (the sand crab, Portunus pelagicus
and the mud crab,
Scylla
serrata;
Family Portunidae) into different nearshore estuarine
habitats (seagrass, mangroves and mudflats) within Moreton
Bay, southeast Queensland. These two species form an
important component of Queensland's commercial catch of
crustaceans, with up to 84% of the State's catch of sand
crabs originating in Moreton Bay.
P.pelagicus and S.serrata have similar life histories, with gravid
females migrating to deep water offshore to spawn.
The final larval stages, the megalopae, are carried back
into the estuarine shallow water where they metamorphose
and settle. Juvenile mud crabs are generally found in
mangrove-lined creeks and mangrove intertidal areas, while
juvenile sand crabs are usually associated with seagrass
beds, but there are few data on the patterns of
distribution and abundance of juveniles in different
regions or estuarine habitats around Moreton Bay, nor is
there information on the specific habitat requirements for
settling larvae or newly recruited
juveniles.