4,221 results
Environment
Environment
PROJECT NUMBER • 2001-008
PROJECT STATUS:
COMPLETED

Assessment of seal fishery interactions in the South East Trawl Fishery (SETF) and the development of fishing practices and seal exclusion devices (SEDs) in the winter blue grenadier fishery to mitigate seal bycatch by SETF trawlers

Introducing a Code of Fishing Practice aimed at avoiding seals appeared to halve the incidence of seal bycatch in this fishery. In SED trials, the problems of fish-loss via the SED escape hatch and net blockage via the SED grid were solved by changes in SED design. Although the effectiveness of most...
ORGANISATION:
Department of Agriculture, Fisheries and Forestry (DAFF) ABARES
Industry
PROJECT NUMBER • 2016-406
PROJECT STATUS:
COMPLETED

Australian Society for Fish Biology: Scientific networking, early career development and international engagement

The 2019 ASFB conference was held in Canberra from 14 to 17 October, 2019 at the National Library of Australia, ACT. The conference theme of “Communicate to illuminate & inspire" encouraged the 251 delegates (including 62 students) from across Australia, New Zealand, Europe, South Africa,...
ORGANISATION:
Australian Society For Fish Biology Inc
Environment
PROJECT NUMBER • 2003-045
PROJECT STATUS:
COMPLETED

Stock discrimination of blue-eye trevalla (Hyperglyphe antarctica) from Australian shelf waters and offshore seamounts and New Zealand

This work is principally about identifying the best method for examining the population structure of blue-eye trevalla (Hyperoglyphe antarctica). It is not, and was never intended to be, an exhaustive assessment of stock structure of blue-eye trevalla in Australia’s Fishing Zone. As such,...
ORGANISATION:
Agriculture Victoria

Investigation of methods to age abalone

Project number: 1992-040
Project Status:
Completed
Budget expenditure: $180,733.75
Principal Investigator: Robert W. Day
Organisation: University of Melbourne
Project start/end date: 25 Oct 1992 - 29 Jun 1998
Contact:
FRDC

Objectives

1. To learn how to age abalone in order to reuce the costs and increase the efficiency of management in Tasmania, NSW, Victoria, South Australia and possibly Western Australia.

Final report

ISBN: 07325-15300
Author: Dr R.W. Day
Final Report • 1997-08-05 • 2.59 MB
1992-040-DLD.pdf

Summary

Management of the valuable Australian abalone fishery is difficult because catch/effort information for abalone does not provide warnings of declining stocks. In fact abalone fisheries in Alaska, California and Mexico have collapsed or declined dramatically, with little warning. Management must rely on a detailed knowledge of how fast abalone grow, when they become adult, how many eggs they produce, and how fast they die of natural causes. But these statistics vary between areas, and it would be very costly to measure them at enough sites for efficient management. Management of fin­fish stocks has been revolutionised by accurate methods to age fish, using layers in the ear bones. Ageing abalone was identified as a high priority as long ago as 1986 in an abalone research review for the then FIRDC. An ageing method would allow biologists to work out growth, natural death rates etc. rapidly and at low cost. The industry would benefit from increased security, as uncertainty about the state of the stocks is a major problem for stakeholders. A reliable method would be used by state organisations to assess stocks more effectively, thus reducing the risk of a collapse or severe fluctuations in quota.

Previous work showed layers in the spire of the shell might be useful to age both blacklip and greenlip abalone, but the evidence relates only to juveniles , and in some areas layers did not correspond to age. We proposed to show when and how age could be estimated from layers, by "timestamping " tagged abalone at sites in each state. "Timestamping" involves staining the shell layer that they deposit over a few days. When the abalone were recovered, the number of layers deposited after the timestamp stain would show how regularly layers are deposited. We set out to mark abalone shells with fluorochrome stains , used by dentists to look at the growth of teeth, and to timestamp rings in fish ear bones. Work in New Zealand had also shown that abalone could be marked with a fluorochrome.

The project began in December 1992. By June 1993 we had established that abalone were stressed and often died after injecting stains, but they were unaffected when immersion in seawater dosed with the stains, and we had tested and compared five stains in the laboratory, and identified concentrations and immersion times that produced strong marks. This achieved our first milestone. Milestone 2 was the demonstration of the "timestamping" method in the field. By the end of 1993 we had developed underwater staining tanks, and collected, tagged and stained abalone with two fluorochrome stains underwater. Our results were reported at abalone divers meetings , and the international abalone conference in Hobart in February 1994. The symposium paper is now published.

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PROJECT NUMBER • 2010-738
PROJECT STATUS:
COMPLETED

SCRC: Reducing inflammation in the elderly with a high seafood diet

With ageing, the inflammatory process is aggravated and it is becoming increasingly recognised that chronic, low-grade inflammation is associated with increased risk for cardiovascular, and a number of other, chronic diseases. The role of nutrition in the development and resolution of inflammation...
ORGANISATION:
Flinders University
Environment
PROJECT NUMBER • 1997-111
PROJECT STATUS:
COMPLETED

Catch-at-age, age at first spawning, historical changes in growth, and natural mortality of SBT: an integrated study of key uncertainties in population biology and dynamics of SBT, based on direct estimates of age from otoliths

The CCSBT has recognized for a number of years that a better understanding of the population biology and demographics of southern bluefin tuna (SBT) is necessary for improved population modeling and stock assessments. In 1996, the CCSBT Scientific Committee identified three areas where our...
ORGANISATION:
CSIRO Oceans and Atmosphere Hobart
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