Can spatial fishery-dependent data be used to determine abalone stock status in a spatially structured fishery?

Funded Activity Summary

With the advent of the Status of Australian Fish Stocks (SAFS) process, there is now a requirement to provide a stock ‘status’ determination in addition to the annual TACC determination. The ‘status’ reflects changes in the overall biomass, the fishing mortality, or in their proxies. This has led to disagreements among researchers, managers and industry, largely due to uncertainty around how best to derive a meaningful overall stock status indicator to meet the requirements of the SAFS reporting process. These higher-level reporting processes are an important demonstration of sustainable management of Australian fisheries, but only if stock status determinations are accurate and defensible.

Australian abalone fisheries primarily use harvest control rules based around CPUE (Kg/Hr) to set TACC. However, with abalone, stable catch-rates may not indicate stable biomass and/or stable density. Catch-rates are frequently criticised because the effort needed to take a quantity of catch may be influenced by density but also by density independent factors such as conditions at the time of fishing, experience, and the ability of fishers to adjust their fishing strategy to maintain catch rates (diver behaviour driven hyper-stability). While there are many issues with the assumption that CPUE is a reliable proxy for abundance, it is assumed to be so despite the absence of robust data to validate use of CPUE in this way. In some jurisdictions CPUE is supplemented by sparse fishery-dependent size and density data. There is an urgent need to review common assumptions, methods and interpretations of CPUE as a primary indicator, and to determine whether inclusion of spatial fishery data could provide a ‘global’ indicator of stock status for abalone fisheries.


Objectives:
1. Characterise the statistical properties, coherence, interpretability and assumptions of spatial and classic indicators of fishery performance
2. Develop methods for inclusion of fine-scale spatial data in CPUE standardisations
3. Identify methods for detecting hyper-stability in CPUE
4. Determine feasibility of spatial data based stock status determination in spatially structured fisheries

Funded Activity Details

Start Date: 01-08-2018

End Date: 30-09-2020

Funding Scheme: Funding Scheme not available

Funding Amount: $562,128.00

Funder: Fisheries Research and Development Corporation

Research Topics

ANZSRC Field of Research (FoR)

There are no FoR codes available for this funding activity

ANZSRC Socio-Economic Objective (SEO)

There are no SEO codes available for this funding activity

Other Keywords

Biomass | Distribution | Mortality | Population Dynamics | RAC TAS | Stock Assessment | Sustainability

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