Legal Minimum Lengths and the Management of Abalone Fisheries

ABSTRACT A management strategy evaluation framework was used to simulate multiple populations making up a management or quota zone for Australian blacklip abalone (Haliotis rubra). The simulation was conditioned on the properties of blacklip abalone and its fishery on the east coast of Tasmania. Abalone are well known for exhibiting spatial heterogeneity in their biological properties. Each population in the simulation was represented by a size-based population dynamics model and had biological properties of growth, maturation, emergence from crypsis, and mortality specific to each population; the range of these properties varies to different degrees in the different quota zones around Tasmania. The simulation was used to compare the effects of applying different legal minimum length (LML) regulations on the fishery. Because of spatial heterogeneity in growth, a single LML within a zone has always been a compromise between underprotecting some populations and overprotecting others. The simulation was used...