Project number: 2001-068
Project Status:
Budget expenditure: $514,757.00
Principal Investigator: Lynda Bellchambers
Organisation: Department of Primary Industries and Regional Development (DPIRD) WA
Project start/end date: 22 Jul 2001 - 22 Mar 2006


Specifically the ongoing management and development of WA commercial and recreational crab fishing requires:
1. A fishery independent method to assess annual variation in pre-fishery recruitment strengths to enable variations in catch data due to effort or technology changes to be distinguished from environmental variations in recruit survival. This will also enable the strength of the recruitment to be predicted in advance, which may allow for a pro-active management approach to be adopted.
2. Improved methodologies for estimating stock abundance and size from newly surveyed areas using developmental fishing (e.g. Shark Bay Developmental fishery), to enable more rapid assessment and allocation of fishing areas.
3. The validation of the allocation model adopted in Cockburn Sound and Geographe Bay, based on differential size limits and commercial effort control, and the associated development of low cost recreational catch monitoring systems to assess ongoing variations to catch shares. These data complement the more detailed data collected from creel surveys as it focuses on the key recruitment periods. An allocation model that allocates the catch between the commercial and recreational sectors, 5/8:3/8 respectively, is currently in place for Cockburn Sound. Therefore it is important that a cost effective annual monitoring program is available to confirm its success.
4. To collect baseline data on currently unfished stocks of blue swimmer crabs to allow comparisons between ongoing developmental fisheries and established fisheries. This provides an opportunity to collect data on the fishery from commencement and to examine any changes caused by fishing pressure.
5. An assessment of the applicability of the SA model for blue swimmer crabs to WA commercial catch data from longstanding fishing such as is available for Cockburn Sound is required, to enable the ongoing stock assessment of the WA blue swimmer crab fisheries for annual ESD reporting.
6. The development of a dedicated blue swimmer crab database to record ongoing commercial catches and data from exploratory fishing permitted during the life of the project.


1. To determine if the abundance of juveniles can be used to predict the relative strength of the subsequent recruitment of the adults of this species into the fishery.
2. To develop low cost annual recreational catch monitoring methods for resource allocation adjustments.
3. To assess the relative impacts of minimum size and fishing effort controls on the resource shares in Cockburn Sound and Geographe Bay.
4. To work with industry to collect baseline data on unfished stocks of blue swimmer crabs by developmental fishing, which is necessary to set initial catch limits, in selected areas along the coast of Western Australia.
5. To provide an assessment for the Shark Bay developmental fishery, based on commercial fishing and tagging data, as a means of developing methods for rapid assessment of new areas.

Final report

ISBN: 1-877098-77-9
Author: Lynda Bellchambers

Related research


Optimising Compliance Outcomes in Recreational Fisheries

1. To characterise the quality and contents of compliance datasets held by WA and SA government agencies and specific to two recreational blue swimmer crab fisheries, in order to evaluate their adequacy for social science research objectives such as longitudinal studies.
University of Western Australia (UWA)