Aspects of the breeding cycle and fecundity of the female West Coast rock Lobster, Jasus Telendii.

Abstract

This study examined the breeding cycle and fecundity of female west coast rock lobster, Jasus lalandii. Seasonal fluctuations in the biochemistry and indices of ovary and hepatopancreas state were monitored to elucidate the partitioning of organic resources between growth and reproduction. Samples were collected monthly from Hout Bay, a fast growth area, and Olifantsbos, a slow growth area, between February 1994 and January 1995. Peak ovarian activity was between January and June and was characterized by the dominance of ripe and ripening ovaries. The increased ovarian production was accompanied by high gonadosomatic indices (GSI) and high ovarian lipid and protein contents. The berry (incubation) period was defined by a dominance of spent and recovering ovaries coupled with low GSI and low ovarian lipid and protein values. After October, the ovary recovered and consequently the GSI, ovarian lipid and protein contents increased. Smaller size classes of females exhibited a dominance of immature to active ovaries throughout the breeding cycle. Smaller females from Hout Bay (50-60 mm) size class showed no clear seasonal trend in GSI and ovarian lipid and protein contents. However, smaller females from Olifantsbos exhibited higher GSI and ovarian lipid and protein during the ovarian growth phase than similar size females from Hout Bay. This was reflected in the greater fecundity exhibited by smaller females from Olifantsbos. In all females, GSI, ovarian lipid and protein content increased with increasing ovarian maturity and declined sharply in spent ovaries.