Population dynamics of shrimp populations in Western Port Bay, Victoria

This study investigated seasonal variation in the abundances and size distribution of shrimp species in Western Port Bay, Victoria from July 1977 to January 1980. Four species, Macrobrachium intermedium, Pontophilus candidus, Hippolyte caradina and Chlorotocella leptorhyncus, were sampled using a beam trawl as described in the record 'The ecology and trophic role of caridean shrimps in the eelgrass community of Western Port, Victoria' (File identifier: 268431c0-f18e-11dc-aaae-00188b4c0af8). Individuals in each sample were counted, identified, sexed, size measured (total length, carapace length), and reproductive state of females noted. The relationship between body size and ash-free dry mass was obtained in order to calculate the standing crop and productivity of each species.

M.intermedium was the numerically dominant shrimp species in the eelgrass. Mean densities of P.intermedius and H.cardian were 20-50% and 3-4% less abundant than M.intermedium, respectively. Maximum abundances of M. intermedium and P.intermedius occurred early in the year and coincided with the recruitment of large numbers of juveniles. Densities of H.caradina showed high variability between years. Low capture efficiency of C.leptorhyncus meant that this species was excluded from the analyses.