Determining when and where to fish: Linking scallop spawning, settlement, size and condition to collaborative spatial harvest and industry in-season management strategies

Funded Activity Summary

Spatially explicit harvest strategies employed in the southeast Australian commercial scallop fisheries aim to buffer against recruitment variation to increase both production and continuity between seasons. As part of these harvest strategies, biomass surveys determine areas to be opened the following season. Areas with >20% discard rate are closed to fishing, regardless of scallop quality and potential for opening during the season. Additionally, scallops in the areas opened are often unsuitable for harvest due to poor condition when the season opens. This means the areas are opened then rapidly closed to fishing again, causing disruption to fishing/processing businesses, and marketing problems. Delayed opening while scallops gain condition can also prevent the total catch being taken because there is a fixed, pre-determined finish date. The fixed finish dates have been established to protect settling scallop spat, which occurs between September and December following spawning between August and October. The problem with poor condition at the start of the season has arisen because scallops are increasingly reaching spawning condition between December and February. As well as potentially putting settling scallops at risk through impacts upon opening the fishery, this late development is also contributing to difficulty in providing well-conditioned scallops throughout the season. This project aims to better define timing of peak scallop spawning and hence settlement across the fisheries and work with Management and Industry to incorporate condition and a more focused use of the 20% rule into complementary management strategies to improve production and business planning. As this project will be conducted at a fishery level across all three jurisdictions, the aim is also to provide information that will allow the jurisdictions greater capacity to work together to facilitate effective management for the fishery as a whole.

Objectives:
1. To better define the timing of spawning and settlement of commercial scallops across the three fisheries.
2. To better define differences in spawning potential between scallops ranging from 80 to 90 mm and gain an understanding of growth rate in this size range.
3. To define agreed operational measures of spawning condition for use in the scallop fisheries.
4. To establish season openings and closings that are more responsive to annual changes in spawning condition and timing of settlement.
5. To define an agreed use of the minimum size limit and 20% discard rule to open/close individual beds.
6. To incorporate spawning condition and a more focused use of the 20% discard rule into cooperative spatial harvest and industry in-season management strategies to enhance the operation and profitability of the fisheries.

Funded Activity Details

Start Date: 01-06-2012

End Date: 23-07-2015

Funding Scheme: Funding Scheme not available

Funding Amount: $272,542.00

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)

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Other Keywords

Economic | Habitat | Productivity | RAC TAS | Workshop

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