Project number: 2011-028
Project Status:
Budget expenditure: $105,167.00
Principal Investigator: Malcolm Haddon
Organisation: CSIRO Oceans and Atmosphere Hobart
Project start/end date: 31 Oct 2011 - 29 Sep 2013


Incidental catches of species whilst fishing includes the take of both quota and non-quota species. Generally these species are relatively data poor but the Harvest Strategy Policy still requires a determination of whether these species are at risk of overfishing.

In addition, bycatch TACs are set for seriously depleted species to allow for those catches taken when legitimately targeting associated species. The objective is to provide a mechanism that would prevent useless discarding while minimizing fishing mortality. However, current regulations do not prevent targeting the bycatch-only species given sufficient quota. This has been observed with School Sharks. It is currently unknown if taking the bycatch TACs for the species concerned will permit the required stock recovery. As a minimum, methods are needed for determining whether an observed level of bycatch and discarding, in any given fishery, is sustainable; these methods need to be able to be applied irrespective of the different life history characteristics of the wide array of bycatch species found across Commonwealth fisheries.

There is a need to explore the conditions under which severely depleted species may fail to recover. If it is the case that for some species even small incidental catches are sufficient to maintain a species in a depleted state then different management may be required. Management options include 1) status quo, 2) spatial and/or seasonal closures, 3) increased cooperation from Industry, 4) changing regulations about bycatch –only species, and 5) reducing the quotas for those species with which the depleted species make up a significant bycatch. The issue of incidental catches is present in all Australian fisheries; there is a need for general solutions that can be applied to a wide range of cases that minimize the impact on the fishery while minimizing the impact of the fishery on the bycatch-only species.


1. Develop guidelines and tests to determine if incidental catch levels for any species are likely to be unsustainable or contrary to the principles of the Harvest Strategy Policy, with particular reference to species under rebuilding strategies and provide case examples.
2. Conduct risk assessments to determine acceptable levels of incidental catch TACs for species under rebuilding strategies (e.g. School Shark, Blue Warehou and Gemfish as case studies) within the parameters of the Harvest Strategy Policy.
3. Determine whether any of the methods developed under objectives 1 and 2 can apply to relatively data poor species
develop guidelines for application to species for which there is only catch data.
4. Assess the feasibility of extending the methodology above in objective 1 to develop a practical and workable methodology to estimate acceptable capture limits for rare and TEP species.

Final report

ISBN: 978-1-4863-0730-2
Author: Malcolm Haddon

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