Oral Presentation Australian Society for Fish Biology Conference 2024

Genetic Analysis and Risk Assessment Framework for Greenlip Abalone Stock Recovery in South Australia (111057)

Stephen Mayfield 1 , Ben Stobart 1 , Katherine Heldt 1 , Sarah Catalano 1 , Ben Freeling 1 , Richard McGarvey 2
  1. The South Australian Research and Development Institute, West Beach, SA, Australia
  2. SARDI, West Beach

This study, conducted from 2021 to 2023 by SARDI Aquatic and Livestock Sciences, aimed to facilitate abalone stock recovery in South Australia through three key activities. First, we compared genetic differences between wild and hatchery reared Greenlip Abalone (Haliotis laevigata) using single nucleotide polymorphism (SNP) techniques. Tissue samples from eight wild sites and three hatchery cohorts were analysed. Results revealed distinct genetic diversity and population structure between wild and hatchery abalone, with wild populations showing slightly higher allelic richness and expected heterozygosity.

Second, we developed a genetic risk-assessment framework through an expert-based workshop to evaluate the suitability of releasing hatchery-reared abalone into wild populations. This objective, consequence-likelihood format assessment identifies key risk factors and provides guidelines for scoring and ranking potential risks associated with abalone releases for stock recovery or subtidal aquaculture.

Lastly, we created a preliminary cost-benefit analysis model with a user interface to assess the economic viability of juvenile Greenlip Abalone releases. The model incorporates growth, survival, release costs, fishing, and harvest value parameters, comparing outcomes with alternative investment strategies.

This multifaceted approach provides valuable tools for assessing genetic risks and economic feasibility of abalone stock enhancement efforts in South Australia, laying the groundwork for future in-water release and monitoring phases.