Moreton Bay sand bug stock assessment

Assessment charts

Chart of Australian east coast stock assessment biomass estimates and key management actions for sand bug.
© Queensland Government
Chart of estimated retained catch for Queensland east coast sand bug from 1968 to 2021.
© Queensland Government

Why did we assess the sand bug stock?

In 2023, Fisheries Queensland completed the first stock assessment of the east coast sand bug stock.

The 2023 sand bug assessment used a delay-difference biomass model based on previous stock assessments. The assessment used the most current biological, survey and commercial catch data to estimate the:

  • biomass of the biological stock
  • fishing pressure on the biological stock.

In the 2023 assessment for sand bugs, 13 model scenarios were run, covering a wide range of modelling assumptions. For sand bugs, results for the base case (project team preferred) scenario indicated that biomass in 2021 was between 63% and 94%, most likely at 78% for the east coast sand bug stock north of 26 degrees latitude.

Stock assessment project team

The project team had a wide range of skill sets and included:

  • managers, scientists, monitoring and data specialists from the Department of Agriculture and Fisheries
  • 3 industry representatives
  • an external scientist.

The team operated under a terms of reference (PDF, 207.9KB) to ensure a transparent and evidence-based approach.

We thank the project team for contributing their time and knowledge, and engaging constructively over the course of a 16-month project.

We acknowledge the significant time commitment and deep operational and technical expertise of our industry representatives. The project has benefited greatly from their input. Future assessments should continue to engage with industry members to further enhance assessments and build collaboration between industry and government.

Next steps for fishery management

Under the Queensland harvest strategy policy (PDF, 1.46MB) and Trawl fishery harvest strategies 2021–2026, management strategies are applied to keep stocks above the limit reference point (20% biomass) and set a target reference point to manage stocks toward.

The trawl fishery working group:

  • provides advice on implementing the fishery harvest strategy
  • considers what management changes may be needed to respond to the stock assessment
  • may suggest future research or monitoring activities to improve the confidence of the stock assessment.

The working group includes representatives from harvest, post-harvest and conservation sectors.

More information

Read the Stock assessment of Moreton Bay bugs (Thenus australiensis and Thenus parindicus) in Queensland, Australia report—with data to December 2021.