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Monthly monitoring of puerulus settlement across South Australia, Victoria and Tasmania has been undertaken since the early 1990s. Firstly, annual trends in settlement were spatially analysed across the three States. In South Australian and Victorian settlement patterns were closely related. In Tasmania, settlement sites along the northeast coast were positively correlated, but showed no relationship with areas further south or in any other State. Secondly, annual settlement indices were correlated with lagged estimates of fishery recruitment. In South Australia, the strongest correlations between settlement and recruitment to legal size were observed using a 4–5- year time-lag. Within Victoria and Tasmania, the period from settlement to recruitment at 60 mm carapace length (CL) was 2 and 3 years, respectively. The period from 60 mm to legal size was another 2–3 years, suggesting that the total time from settlement to the fishery ranges from 4–6 years in these regions. The correlation between settlement and recruitment was used to forecast future estimates of exploitable biomass in one region of South Australia. The results indicate that puerulus monitoring is a relatively robust indicator of future fishery performance and should be regarded as an important data source for rock lobster resources within south-eastern Australia.

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Southern rock lobster Jasus edwardsii varies in shell coloration throughout southern Australia. Predominantly exported as a live product to Asian markets, price is influenced by colour with prices higher for dark red than paler coloured lobsters, which are discounted. This paper explores spatial and depth variation in shell colour for the Tasmanian, South Australian and Victorian fisheries using catch sampling data. The proportion of red lobsters decreased with depth and was prevalent at depths less than 30 m, whereas paler coloured lobsters dominated the deeper depth ranges. The depth of transition where 50% of lobsters were classified as red showed a weak trend of increase with latitude from southern Tasmania to northern South Australia. Under quota management, lobster colour was a significant driver of fleet dynamics as fishers target areas of high price per unit. Consequently, catches of pale lobsters from greater depths remain low despite the high catch rates in these areas. The colour price differential varies seasonally (higher in summer) so fishers increase supply of pale lobsters during winter. Discounting on colour equates to AUS$6.67 million/year for the Tasmanian Fishery alone, which indicates value from management or marketina research to reduce discountina.

Field and experimental studies were undertaken in four European countries on clawed lobster (Homarus gammarus) ecology and recruitment. The aims were to assess: (a) abundance of early benthic phase (EBP) lobsters and other benthic species at cobble sites, (b) the effect of these species on EBP growth and survival, and (c) influence of these factors on recruitment and/or viability of restocking. Suction sampling of cobble sites revealed a wide diversity and abundance of potential competitors but no EBP lobsters. Hatchery-produced EBPs were therefore used for small-scale mesocosm experiments. In nature, predation on EBP was rapid without shelter, whereas in-vitro mortality, growth, and behaviour experiments showed that cover potentially increases survival. Scarcity per se may not completely explain the apparently absence of EBP, given that not a single EBP lobster was located either during this study or during any other of the extensive benthic investigations. The present paper discusses the implications of their apparent absence and whether it arises because EBPs are very scarce, cannot be captured by suction sampling, are not within lobster habitat, or occupy a specialized niche within adult habitat outside the range of current sampling methods.

Movement patterns of the southern rock lobster Jasus edwardsii were determined from 14 280 tag-recapture events across South Australia between 1993 and 2003. In total, 68% of lobsters were recaptured within 1 km of their release site and 85% within 5 km. The proportion of lobsters moving >1 km in marine fishing areas (MFAs) ranged from 13% to 51%. Movement rates were noticeably high in the south-east and at Gleesons Landing lobster sanctuary off the Yorke Peninsula but patterns of movement differed spatially. In the south-east, lobsters moved distances of <20 km from inshore waters to nearby offshore reefs whereas at the Yorke Peninsula, individuals moved distances > 100 km from within the sanctuary to sites located on the north-western coast of Kangaroo Island and the southern end of Eyre Peninsula. In total, 85% of all lobsters released inside the sanctuary moved distances >1 km. Movement was highest in immature females within most MFAs. Females also remained at large an average of 124 days longer than males. The high variation in lobster movement observed across South Australia highlights the need for locally derived, regionally specific data when assessing the proposed location and subsequent modelling of marine protected areas. This is of particular importance to inshore areas, where movement rates of lobsters were highest.