The growth and reproductive patterns of abalone are central to an understanding of the dynamics of their populations, and provide essential input into many of the stock assessment models currently used as the basis of assessing the sustainability of the fisheries. At present, most of this knowledge is obtained by tag-recapture methods, which are time consuming, often expensive and potentially confounding. The aim of the present study was to determine whether variations in the ratios of oxygen and carbon isotopes in the shells of Haliotis iris can be used to determine age, growth and reproductive patterns. Isotopic analyses of H. iris shells indicated that oxygen isotope profiles within the shells reflected ambient water temperature at the time of shell precipitation, and that these profiles could be used to determine age and growth patterns. To match the variation in isotopic ratios with ambient temperature cycles, we also adopted the novel approach of fitting a growth function to the data sets. The method should allow the collection of abalone growth information over the finer scales more appropriate for the rational management of abalone fisheries. Variations in the ratios of carbon isotopes showed no consistent patterns and, unlike some mollusc species, did not appear to be useful predictors of reproductive status at length.
- Growth model
ASJC Scopus subject areas
- Ecology, Evolution, Behavior and Systematics
- Aquatic Science