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It is widely accepted that the identification and management of abalone populations is critical for the ongoing sustainability of the fishery. However management of the endemic blacklip abalone throughout the Australian states generally occurs over large spatial scales and in some instances, across morphologically different populations on a finer scale. In this study, we use molecular techniques to show that blacklip abalone from seven sampling sites (of which four sites were characterized by stunted abalone growth patterns) in South Australia were genetically homogenous. Ten microsatellite loci and five composite restriction fragment length polymorphisms from the ND3/COIII mtDNA region showed high levels of genetic diversity across the collections, irrespective of growth characterization. Both molecular techniques also revealed a concordant outcome; no significant hierarchical variance was detected across geographically close, yet morphologically different collections (microsatellite ΦST = 0.002; mtDNA ΦST = -0.010). Pair-wise FST estimates were also low and often negative for the microsatellites (FST = -0.002 -0.007) and mtDNA markers (FST = -0.023-0.011). Our current findings support the hypothesis that blacklip abalone sampled here from "stunted" and "non-stunted" collections in the southern zone of the South Australian fishery are genetically similar. [ABSTRACT FROM AUTHOR]

Neutral red retention (NRR) assay was used to evaluate the effect of changes in water temperature on lysosomal membrane integrity in the hemolymph of blacklip abalone, Haliotis rubra. Results from gradual temperature changes between 7°C and 16°C and between 16°C and 25°C showed that water temperatures within the range of 15°C to 17°C were optimal for maintaining lysosomal membrane integrity in this species. The rapid temperature changes between the ranges used in the gradual temperature change experiments indicated that when abalone were transferred directly between these temperatures their NRR time gradually increased or decreased to the level corresponding with the new temperature. However, when abalone were transferred directly between 7°C and 25°C or between 11.5°C and 20.5°C their NRR times initially decreased significantly, and then gradually increased to the levels corresponding with the new temperatures, indicating that different ranges of water temperature change can affect the lysosomal membrane integrity differently. The NRR times of blacklip abalone at 7°C, 16°C and 25°C were 40.0 ± 2.89 min, 113.33 ± 3.85 min and 35.0 ± 2.89 min, respectively. [ABSTRACT FROM AUTHOR]