Assessing the spawning characteristics and reproductive biology of Pearl Perch (Glaucosoma scapulare) in Queensland
Department of Agriculture and Fisheries EcoScience Precinct
This project addresses the national research priority "Ensuring that Australian fishing and aquaculture products are sustainable and acknowledged to be so", identified by FRDC as part of their RD&E Plan for the period 2015-2020. Further, this project addresses a research priority listed in FRDC's April 2018 Competitive round call for Expressions of Interest "To gain a better understanding of the spawning aggregations and dynamics of pearl perch". This project also addresses a Fisheries Queensland’s priority identified in their 2017 Monitoring and Research Plan "Research into lifecycle characteristics of pearl perch". Outputs from a recent stock assessment suggested that the pearl perch stock, which extends southwards into New South Wales waters, is transitional depleted and stock recovery is necessary. This requires an improvement in egg production achievable through the protection of spawning animals. Knowledge of the pearl perch’s spawning dynamics would enable fishery managers to make evidence-based decisions regarding the harvest strategies that increase egg production and, therefore, build the stock biomass. For example, should patterns of pearl perch spawning aggregations be located, like those of the confamilial West Australian dhufish (belonging to the same taxonomic fish family), spatial closures could be employed to protect these aggregations. Similarly, temporal closures are currently used to avoid excessive fishing mortality on coral trout spawning aggregations and similar protection for pearl perch may be appropriate if spawning is timed to coincide with certain biological or seasonal cues. A thorough understanding of these spawning dynamics of the pearl perch is necessary to inform management of the species. There is a need, therefore, to: (1) collect relevant biological information pertaining to the spawning dynamics of pearl perch, (2) supplement current information with fishery-independent data to better define temporal and spatial spawning patterns over the entire extent of the species’ distribution, and (3) identify areas likely to support spawning aggregations, if any, and to assess the movement to and from these spawning aggregations.
1. Assess the temporal and spatial trends in the reproductive biology of pearl perch
2. Determine the movement of spawning pearl perch using both conventional and acoustic tagging methods
3. Identify areas, if any, that support spawning aggregations and determine the relative importance of these aggregations to the sustainability of the pearl perch stock