PROJECT NUMBER
•
2009-756
PROJECT STATUS:
COMPLETED
ORGANISATION:
University of Tasmania (UTAS)
169 results
Assessment of broad-scale exploitation rates and biomass estimates for the Tasmanian southern rock lobster fishery
Project number:
1997-101
Project Status:
Completed
Budget expenditure:
$468,370.00
Principal Investigator:
Stewart Frusher
Organisation:
University of Tasmania (UTAS)
Project start/end date:
22 Jun 1997
-
29 Apr 2003
Contact:
FRDC
Traditionally, catch per unit of effort (CPUE) is used to monitor the health of the fishery and indicate the success or otherwise of management practices. Under current input controls CPUE is based on fishers maximising their total catch. In contrast, under output controls where catch is predetermined fishers will alter their catching scenarios to maximise the return (dollars per kilogram) from their catch. In southern rock lobster fisheries there is significant potential to alter fishing patterns to maximise economic return, especially through seasonal shifts in effort. As this change occurs, the value of using CPUE data to continue monitoring the fishery will be eroded. As such, both fisheries independant means of monitoring the fishery and new monitoring methods will become increasing important.
Both exploitation rates and biomass estimates are important stock assessment parameters and biological reference points in sustainable management of fisheries resources.
This project will evaluate fishery independant means of deriving these estimates and by determining the precision of derived estimates, demonstrate their suitability as biological reference points.
In a report to the Department of Industry, Technology and Commerce titled "Oceans of Wealth?", the Review Committee on Marine Industries, Science and Technology stated in their conclusion, 'The knowledge gained from scientific research into fish stocks and the impacts of the environmental and harvesting factors is a necessary but not sufficient element in the conservation of productive fish stocks. A vital element in both scientific assessments is the availability of reliable information about exploitation levels'. This project is aimed at addressing this need for southern rock lobster.
1. To assess the precision of exploitation rates and biomass estimates derived from broad scale sampling using fisheries independant and fishery dependant sampling.
2. To evaluate both the precision and cost effectiveness of biomass estimation from fisheries dependant and fisheries independent derived exploitation rates and recommend future monitoring methodology for the rock lobster fishery.
Final report
ISBN:
1-86295-079-2
Author:
Stewart Frusher
Final Report
•
2003-03-25
•
2.06 MB
1997-101-DLD.pdf
Exploitation rate is an important fishery assessment parameter linking catch to legal-sized biomass, the portion of the stock available for harvest. Relative change in legal-sized biomass is a crucial performance indicator for the fishery as it measures the success of management outcomes. Under the recently introduced Individual Transferable Quota Management System (ITQMS) in the Tasmanian rock lobster fishery, rebuilding of legal-sized biomass is a key management objective. The assessment model that produces biomass estimates for this fishery is primarily dependent on commercial catch and effort data.
The use of commercial catch and effort data for stock assessment relies on its de facto relationship with stock abundance. However, the relationship between catch and effort data and abundance is not always constant or linear. Improvements in fishing gear and technology can result in greater catch for a given amount of effort, unrelated to changes in the biomass. Management changes and fishers’ behaviour can also affect the relationship between catch rates and biomass. Under the new ITQMS introduced in 1998, catch is fixed and improved profits can be made by improving the return per unit of fish caught rather than by increasing the amount of catch through increased effort. Thus fishing during periods when catch rates are low but price is high can change the catch effort relationship independent of biomass change.
Fishery independent surveys, using established sampling protocols and standardised fishing gear are a way in which catch rates can be standardised irrespective of gear efficiencies or fisher’s behaviour. If these surveys can also produce accurate estimates of exploitation rate then accurate estimates of biomass can be achieved, provided the exploitation rate estimates are representative of the fishing grounds. Fishery independent estimates of exploitation rate are thus a valuable way of validating model biomass estimates especially with the introduction of an ITQMS where the relationship between catch rates and legal-sized biomass was likely to change pre- and post-quota.
This project aimed to trial change-in-ratio (CIR) and index-removal (IR) techniques to obtain estimates of exploitation rate and biomass from broad scale regions in the fishery.
Keywords: southern rock lobster, change-in-ratio, index-removal, exploitation rates, tagging.
PROJECT NUMBER
•
2012-047
PROJECT STATUS:
COMPLETED
ORGANISATION:
University of Tasmania (UTAS)
SPECIES
PROJECT NUMBER
•
2003-050
PROJECT STATUS:
COMPLETED
Linking habitat mapping with fisheries assessment in key commercial fishing grounds
The Tasmanian commercial fishery for blacklip abalone (Haliotis rubra) and greenlip abalone (H. laevigata) contributes a significant component of the total Australian abalone catch, with annual landings of around 2590 tonnes in 2003. The catch consists primarily of blacklip abalone (around...
ORGANISATION:
University of Tasmania (UTAS)
PROJECT NUMBER
•
2008-314.42
PROJECT STATUS:
COMPLETED
ORGANISATION:
University of Tasmania (UTAS)
PROJECT NUMBER
•
1997-321
PROJECT STATUS:
COMPLETED
ORGANISATION:
University of Tasmania (UTAS)
PROJECT NUMBER
•
2002-057
PROJECT STATUS:
COMPLETED
ORGANISATION:
University of Tasmania (UTAS)
SPECIES
PROJECT NUMBER
•
2008-701
PROJECT STATUS:
COMPLETED
ORGANISATION:
University of Tasmania (UTAS)
Review and assessment of the impacts of the proposed broad areas of interest (BAOI) for MPA development in the SE region
Project number:
2005-083
Project Status:
Completed
Budget expenditure:
$52,900.00
Principal Investigator:
Colin Buxton
Organisation:
University of Tasmania (UTAS)
Project start/end date:
28 Jun 2006
-
19 Dec 2006
Contact:
FRDC
1. To quantify the commercial fisheries catch for key species within the proposed MPAs for the SE region
2. To quantify the commercial fisheries economic value associated with the catch within the proposed MPAs for the SE region
3. To quantify the socio-economic impact of the proposed MPAs on the commercial fishing industry
4. To quantify in terms of 1,2 &3 alternative approaches that meet industry needs without compromising biodiversity objectives of DEH.
Final report
ISBN:
0 9577587 6 6
Author:
Colin Buxton
Final Report
•
2006-02-01
•
4.18 MB
2005-083-DLD.pdf
On the 14 December 2005 the Australian Government announced detailed proposals for the establishment of an extensive network of Marine Protected Areas (MPAs) in the South-east Region of Australia. The 14 candidate MPAs would cover more than 170,000 square kilometres of Commonwealth waters off Tasmania, Victoria, southern New South Wales and eastern South Australia.
Simultaneously, the Australian Government’s fisheries management reform, including substantial reductions in Total Allowable Catch (TAC) and the purchase of fishing licenses to remove effort from over fished fisheries, was extended to fishers – both Commonwealth and State licensed – who were affected by the creation of the MPA network. By running a single adjustment package it was reasoned that affected businesses need only go through one adjustment process (rather than two), and businesses in the South-east Region would not face a series of changes over several years.
The gross value of fisheries production from the South-east Region, at over $500 million per annum, represents an estimated 23% of the total gross value of Australian fisheries production.
At the time of the announcement of the proposed MPA network, the boundaries of only two candidate MPAs within the 11 Broad Areas of Interest (BAOIs) had been discussed in any detail with the fishing industry. The Australian Government had brought forward the release of the proposed MPA network so that fishermen could make decisions about their future in the full knowledge of their operating environment – knowing the full extent of proposed exclusions from MPAs as well as knowing how their fisheries would be managed.
This report investigates the considerable impacts that these announcements pose for the fishing industry in the South-east Region and the considerable socio-economic implications for individual fishers who fish within the proposed areas, for entire fisheries, and on the overall supply of seafood to the Australian consumer. On the understanding from the Commonwealth Department of Environment and Heritage
(DEH), that the proposed areas were negotiable, Industry and management agencies believed the most appropriate response was to characterise and validate the impacts and make a scientifically defensible case for alternatives such as boundary changes or alterations to the proposed MPA classifications. These alternatives were designed to minimise the impacts on the fishing industry while at the same time not eroding the conservation values of the proposed MPA network in the region.
PROJECT NUMBER
•
2004-215
PROJECT STATUS:
COMPLETED
Aquafin CRC - Atlantic Salmon Aquaculture Subprogram: establishment of challenge for AGD
This project has increased our knowledge of Amoebic Gill Disease, in particular about the pathogen and the dynamics of infection. We have described a new species of neoparamoeba, Neoparamoeba perurans, and showed that it has been consistently associated with AGD worldwide. Stocking...
ORGANISATION:
University of Tasmania (UTAS)
SPECIES
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