Project number: 2010-006
Project Status:
Budget expenditure: $402,174.00
Principal Investigator: Andrew & Renae Tobin
Organisation: James Cook University (JCU)
Project start/end date: 30 Jun 2010 - 29 Jun 2013


Shark fisheries worldwide are extremely valuable economically though are universally threatened through a combination of high susceptibility to depletion, poor data on levels of fisheries exploitation and uncertainty about what are appropriate levels of exploitation. These facts hold true for the Queensland east coast shark fishery as a high diversity of shark species are harvested through a complex combination of targeted and non-targeted fishing effort spread throughout 18 degrees of latitude. The current data void prevents effectual management, assessment and monitoring; problems well documented by the recent Gunn et al (2008) review of proposed management measures for the Queensland fishery completed for the Hon Peter Garrett MP, Minister for the Environment, Heritage and the Arts. The Gunn et al (2008) review put forward 14 conditions and 8 recommendations, most pertinent being to determine exploitation and mortality rates, and improve the understanding of the shark complex with which the fishery interacts through improved reporting, observing and validation.

Significant changes in the management of the Queensland fishery began on 1 July 2009 and include substantial changes including modifications in the way commercial fishers are permitted to harvest shark stocks, as well as improved catch reporting. The need to move forward quickly in gathering information relevant to sustainable use of Queensland sharks is paramount. The Gunn et al 2008 report concluded that on the basis of the poor coverage of some, and complete absence of other data vital for confident management, the proposed management arrangements for the fishery were insufficiently cautious. The proposed project will directly address not only these concerns, but also the key research priorities relevant to shark identified by the Queensland FRAB.

Gunn, J, Meere, F, Stevens, J (2008). Independent review proposed manage,ment arrangements for Queensland’s east coast Inshore Fin Fish Fishery.


1. Estimate fishing related mortality of major target species and species of conservation interest.
2. Utilising the recapture data provided through objective 1, broad scale movement patterns as well as in situ growth rates will be estimated.

Final report

ISBN: 978-0-9941500-4-2
Author: Andrew Tobin
Final Report • 2015-08-18 • 3.01 MB


Fishing mortality rates for the major targeted and byproduct species of sharks landed by the Queensland East Coast Inshore Fin Fish Fishery (ECIFFF) have been estimated. The effects of these fishing mortality rates on population persistence for these species have also been modelled with demographic analyses to predict future population trends.
The Centre for Sustainable Tropical Fisheries and Aquaculture has completed this project in response to increasing interest and concern by all stakeholders around the status of shark populations exposed to the fishing activities of the Queensland ECIFFF. A large-scale tag-recapture project was completed across 2010 and 2011 and provided the relevant data to complete this exercise. A total of five tagged shark species realised a total of 324 recaptures.
We found that current fishing mortality rates appear generally sustainable. Robust fishing mortality estimates and subsequent demographic modelling outcomes were possible for four of the most dominant species harvested by the fishery – the undifferentiated blacktip shark (Carcharhinus tilstoni/limbatus) complex, spot tail shark (C. sorrah), spinner shark (C. brevipeenna) and pigeye shark (C. ambionensis). For all species except pigeye sharks fishing mortality rates were found to be low to moderate, but likely within sustainable bounds. For the pigeye shark, fishing mortality estimates were relatively high with several methods indicating harvest rates may have been unsustainable. Less robust estimates of fishing mortality were achieved for an additional six species including milk and sharpnose sharks Rhizoprionodon acutus and R. taylori; creek whaler C. fitzroyensis; bull shark C. leucas; and the scalloped and great hammerheads Sphyrna lewini and S. mokarran. For these species estimates are likely highly imprecise and should be used cautiously.

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