Project number: 2002-239
Project Status:
Completed
Budget expenditure: $110,768.00
Principal Investigator: Glen A. Davidson
Organisation: Geraldton Fishermen's Co-operative Ltd
Project start/end date: 29 Jun 2002 - 15 Apr 2005
Contact:
FRDC

Need

With commercial fishermen already beginning to implement cold-stunning there is a critical need to determine possible impacts of this technique on the returned protected lobsters (viability of eggs carried by ovigerous female lobsters and undersized lobsters). Experiments to determine these impacts are already underway as part of FRDC 2000/251.
The proposed tag and recapture work is planned for the 2002/2003 season and is contingent upon the results of these experiments in FRDC 2000/251. FRDC 2000/251 however, is not due for completion until November 2003, but the relevant results will be available well before the start of the 2002/2003 season. Rather than wait until 2000/251 is completed before applying for funds to undertake the tag and recapture work, we are applying in this (2001) round. If the current application is approved, the tag and recapture work will not proceed without 1) first considering the results of egg viability experiments in FRDC 2000/251 and 2) seeking approval to do so from the RLPHS Steering Committee. Delaying application for funds for the tag and recapture study until completion of 2000/251 (in November 2003) will delay this work by at least 2 years.

Objectives

1. To determine the effect of commercial capture with or without cold-stunning on the survival and growth of returned protected western rock lobsters.
2. To observe and film in the wild the behaviour of western rock lobsters caught and returned with or without cold water stunning.

Final report

ISBN: 0-9757298-2-9
Author: Glen Davidson
Final Report • 2005-09-19 • 467.42 KB
2002-239-DLD.pdf

Summary

The relative recapture rates of returned stunned and unstunned lobsters have been quantified. Apparently conflicting results were obtained from two different areas of the fishery, but the results were deemed inconclusive due to low numbers of recaptures from water surrounding the Southern Group of the Abrolhos Islands.

The behaviours of returned lobsters have been observed underwater. Lobsters spending excessive periods of time in the stun tank at 5-10°C showed delayed recovery following return to the ocean. The findings have prompted a second expanded study to investigate the effect of stun time on lobster recapture rates over a wider geographical area.

Related research

Environment
People
Industry
PROJECT NUMBER • 2023-082
PROJECT STATUS:
CURRENT

Australian Fisheries and Aquaculture Statistics 2022

1. To maintain and improve the data base of production, gross value of production and trade statistics for the Australian fishing industry, including aquaculture.
ORGANISATION:
Department of Agriculture, Fisheries and Forestry (DAFF) ABARES