A method for ageing the abalone Haliotis rubra (Mollusca : Gastropoda)

Abstract

A technique for ageing Haliotis rubra is described. The spire of the shell is ground to create a polished disc of nacre in which rings are visible. The number of rings present in each shell is related to the size of the shell. The age at which each ring is deposited has been determined using an age-length key derived from length-frequency histograms and tag return data. For the population studied, three minor rings are deposited in the first 16 months of life and a major ring at an age of approximately 20 months. Subsequent rings are deposited at approximately annual intervals.

Growth Models for Fisheries: The Effect of Unbalanced Sampling Error On Model Selection, Parameter Estimation, and Biological Predictions

“…As the use of growth models increases, the selection of the most appropriate growth model would depend on its performance and uncertainty in other real-world problems, and not just time-to-fishery estimates. The growth of the juveniles vary, with some studies demonstrating that growth is constant over a range of initial sizes (Prince et al 1988, Helidoniotis & Haddon 2012, which is consistent with the inverse logistic model (Haddon et al 2008), or that the growth rate of juveniles increases over the juvenile sizes, which is consistent with the Gompertz model (Shepherd & Hearn 1983, Troynikov et al 1998 …”

The relative suitability of the von Bertalanffy, Gompertz and inverse logistic models for describing growth in blacklip abalone populations (Haliotis rubra) in Tasmania, Australia

“…However, neither of these characteristics have been observed in data from small juveniles. Instead the growth rate of small juveniles has been observed to remain constant rather than decline or increase (Day and Fleming, 1992;Prince et al, 1988). Both the von Bertalanffy and Gompertz growth curves may therefore Fig.…”

Determining age and growth of abalone using stable oxygen isotopes: a tool for fisheries management

“…Stable oxygen isotope ratios may also be a useful tool to validate the frequency with which shell growth rings/layers are produced. Studies of shell growth layers in the spire of abalone shells have been carried out on various haliotid species (Shepherd et al, 1995;Shepherd and Avolos-Borja, 1997;Shepherd and Triantafillos, 1997;Shepherd and Huchette, 1997), and in particular on H. rubra (Prince et al, 1988;McShane and Smith, 1992;Nash et al, 1994). However, validating the number of layers with age has been difficult.…”