The influence of physical oceanographic processes on the dispersal of larvae is critical for understanding the ecology of species and for anticipating settlement into fisheries to aid long-term sustainable harvest. This study examines the mechanisms by which ocean currents shape larval dispersal and supply to the continental shelf-break, and the extent to which circulation determines settlement patterns using Sagmariasus verreauxi (Eastern Rock Lobster, ERL) as a model species. Despite the large range of factors that can impact larval dispersal, we show that within a Western Boundary Current system, mesoscale circulation explains broad spatio-temporal patterns of observed settlement including inter-annual and decadal variability along 500 km of coastline. To discern links between ocean circulation and settlement, we correlate a unique 21- year dataset of observed lobster settlement (i.e., early juvenile & pueruli abundance), with simulated larval settlement. Simulations use outputs of an eddy-resolving, data-assimilated, hydrodynamic model, incorporating ERL spawning strategy and larval duration. The latitude where the East Australian Current (EAC) deflects east and separates from the continent determines the limit between regions of low and high ERL settlement. We found that years with a persistent EAC flow have low settlement while years when mesoscale eddies prevail have high settlement; in fact, mesoscale eddies facilitate the transport of larvae to the continental shelf-break from offshore. Proxies for settlement based on circulation features observed with satellites could therefore be useful in predicting broadscale patterns of settlement orders of magnitudes to guide harvest limits.

structure against a background of genetic homogeneity in the Eastern Rock Lobster, Sagmariasus verreauxi. Marine Biology, 165 (12) .

The eastern rock (spiny) lobster, Jasus verreauxi occurs along the east coast of Australia and North Island of New Zealand. The resource off New South Wales (NSW), Australia, is managed through a suite of input controls and individual catch quotas. The stock assessment process has identified that the length-based model used in annual stock assessments would be improved with more precise information about the species' growth patterns. This study provides the first published information on a growth model for this species by describing the results of tagging experiments from 1995 to 2001 (inclusive). Lobsters were tagged with anchor tags across six locations spanning the main distribution of the species off NSW. The maximum time that a tagged lobster was at liberty was 2573 days. Recapture data were fitted to the von Bertalanffy growth function (VBGF) using Fabens method, including parameters for seasonal growth and individual variability in growth, and extraneous information about the average length and age of puerulus larvae so that the parameter t 0 could be calculated. Males had a longer predicted mean growth increment at 98 mm antennal carapace length (CL) and 202 mm (CL) (g α and g β , the two input sizes used in the model) than females. Transformed values (with CI) for the VBGF parameter K were 0.13 (0.12-0.16) and 0.14 (0.12-0.15) for females and males, respectively. Respective values for the VBGF L xj were 239.77 (224.37-243.51 mm CL) and 246.10 (244.69-280.70). The eastern rock lobster is amongst the largest of the palinurid family. The species is exploited for approximately 4 years before reaching sexual maturity (approximately 8 years of age) and for approximately 3 years after that time until the legal maximum length is attained. These exploitation circumstances expose this longlived species (approximately 30 years) to the risk of recruitment overfishing and consequently this risk is assessed annually through a stock assessment process.

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