Budget expenditure: $75,000.00
Project Status:
Current
Principal Investigator: Bronwyn M. Gillanders
Organisation: University of Adelaide
Project start/end date: 4 Oct 2020 - 30 Jun 2024
Contact:
FRDC
TAGS
Stock Assessment
Resource Access And Allocation
Research
Reproduction
Recreational Fishing
SPECIES
Yellowfin Whiting

Need

The South Australian Marine Scalefish Fishery (MSF) is the most complex fishery in South Australia and is currently undergoing transition through structural reform, development of new harvest strategies and review of the Management Plan. Changes in the dynamics of the fleet have resulted in redirection of effort from primary species such as garfish, snapper and King George whiting towards secondary species including yellowfin whiting.

Yellowfin whiting Sillago schomburgkii is the second most valuable Sillaginid after King George whiting and one of the most valuable secondary species in the MSF fishery with most catches from Northern Spencer Gulf, and smaller catches from the West Coast, Southern Spencer Gulf, and Gulf St Vincent. There are also significant recreational catches (31.5% of State catch in 2013/14).

There is a need for improved understanding of the life-history of yellowfin whiting with quantitative estimates of population dynamics including reproduction, growth performance and stock structure. Oceanographic separation of Spencer Gulf and Gulf St Vincent suggests that yellowfin whiting may constitute separate stocks in these regions while possible population sub-structuring occurring at smaller scales has implications for fishery management. There is potential to compare results of the proposed study with previous work to investigate whether decadal changes in the demography and population dynamics of yellowfin whiting have occurred in the South Australian Gulfs, as well as potential factors driving any change.

This project proposal aims to (i) build the capacity for scientific investigation of finfish species in South Australia by providing an opportunity for a science graduate to develop skills in fishery science, (ii) improve the understanding of life-history and population dynamics of yellowfin whiting, and (iii) improve understanding of the stock structure of yellowfin whiting. This project will have linkages to another FRDC funded project (2017/023), “ESD risk assessment for under-utilised species to facilitate structural reform of South Australia’s commercial Marine Scalefish Fishery”.

Objectives

1. Define the stock structure of yellowfin whiting in South Australia and the relationship to Western Australian stocks using genomic approaches.
2. Define finer scale population structure of yellowfin whiting in the South Australian gulfs using otolith chemistry.
3. Examine spatial and temporal trends in catch among yellowfin whiting and other species in the marine scalefish fishery and how representation among different life-history strategy groups has changed.
4. Investigate size and age structures of yellowfin whiting in the two gulfs of SA and how these have changed over a 22 year period.
5. Increase fisheries science capacity in South Australia through training of the next generation of researchers.

Related research

Environment
Environment
Communities