24,387 results
Environment
PROJECT NUMBER • 1978-036
PROJECT STATUS:
COMPLETED

Tide and current analysis of the Gulf of Carpentaria and its relation to banana prawn larval dispersion

The prawn fishing industry in the Gulf of Carpentaria is worth $100 million/year and a large proportion of this is from catches of banana prawns. In one stage of their complex life history, banana prawn larvae are carried by ocean currents from their spawning grounds to the estuarine nursery...
ORGANISATION:
CSIRO Oceans and Atmosphere Cleveland

Tactical Research Fund: Development and deployment of sterile ‘Judas fish’ to assist carp eradication in Lake Sorell, Tasmania - surgical and chemical sterilisation

Project number: 2012-039
Project Status:
Completed
Budget expenditure: $75,000.00
Principal Investigator: Jawahar G. Patil
Organisation: Inland Fisheries Service (IFS)
Project start/end date: 12 Sep 2012 - 29 May 2014
:

Need

Critically, sterile Judas fish need to be developed/deployed by spring of 2013, before remaining females from the 2009 cohort begin to mature. Delay in project commencement beyond 2012 spring will critically hamper carp eradication in Tasmania.

To date, Integrated Carp Management (ICM) strategy has resulted in eradication of carp from Lake Crescent and contained their population to Lake Sorell, repeatedly demonstrating an ability to fish down new cohorts rapidly. Use of radio-tagged "Judas" male carp to locate and remove aggregations has been the largest contributor (e.g. accounting for >80% of carp captured in Lake Crescent). Despite low adult carp numbers spawning occurred in Lake Sorell (2009), prompted by exceptionally high water levels. Relatively large size of the lake (than Crescent) and resource limitations did not help. Male Judas carp were implicated in this recruitment prompting their removal and replaced by juvenile Judas in 2011- ID feeding aggregations; mature Judas also ID spawning aggregations.

In absence of Judas technique, it is deemed impossible to achieve control let alone eradication, prompting preliminary sterilization trials in 2010. Albeit with low success rate (1/11) the trials were encouraging with further comparative anatomical examinations revealing valuable clues for future refinement. In light of this progress multiple sterilized fish will be ready for deployment by October 2013, should the refinement/experiments commence this spring (2012). Two annual carp programme reviews (10-11 May 2011 and 19-20 May 2012) have recommended the technique/s be developed systematically—including alternative approaches along with hormonal, histological, behavioural and fertility assessment.

Primary objective is to develop/deploy behaviourally least compromised sterile Judas fish. Fish with compromised reproductive behaviour though not preferred are useful in betraying the numerically dominant non-reproductive aggregations.

Expected outcomes will contribute to long-term goals of recreation and commercial fishing sectors in inland waters of Tasmania, with likely interest to other states.

Objectives

1. Refine the surgical sterilization (cauterization) technique
2. Trial two additional sterlization approaches—tubal ligation and Essure
3. Optimise superlorin mediated chemical sterlization
4. Evalute the success of the techniques, including regular assessment of blood testosterone levels, spermiation and fertility of the animals
5. Record gross anatomical and histological changes following surgical and or chemical sterilization of select animals
6. Deploy successfully sterilized carp with radiotransmitters in the lake and map their behaviour — ability to integrate into the population and assist in location of aggregations — general and reproductive

Final report

ISBN: 978-0-646-92546-2
Author: Jawahar Patil and John Purser
Final Report • 2014-08-15 • 2.61 MB
2012-039-DLD.pdf

Summary

In a world first, the project successfully developed reliable procedures for surgical sterilization of male carp and demonstrated that these when deployed as sterile ‘Judas’ fish are as competent as male ‘Judas’ carp in betraying the locations of feral populations thus assisting their capture. Significantly, the sterile Judas fish will mitigate future risks associated inadvertent contributions to spawning and recruitment. The sterile Judas carp are now an integral component of the ongoing carp eradication program at Lake Sorell, Tasmania.

Following the discovery of the carp Cyprinus carpio in lakes Crescent and Sorell in 1995, the Inland Fisheries Service (IFS) decided to eradicate both the populations. While, the Lake Crescent population has been successfully eradicated, the Lake Sorell population has been lingering, owing to inadvertent spawning and recruitment in 2009 —contributed by Judas carp, which are otherwise central to the eradication strategy at the lakes. Responding to the crisis and urgent need to mitigate future recruitment risks this project explored chemical and surgical sterilization options with a view to replace male ‘Judas’ carp with sterile ‘Judas’ carp. 

The primary objective of the project was to develop reliable sterilization technique/s that did not significantly compromise the behavior of the sterilized individuals. Behavioral integrity of the sterilized individuals when fitted with radio-transmitters and deployed as Judas fish (i.e. to assimilate and integrate seamlessly into the wild populations) was/is critical to betraying the locations of aggregations allowing targeted fishing and removal of feral populations. 

Keywords: Common carp, Cyprinus carpio, steroid hormones, Superlorin, testis, tubectomy, Radio-tracking, Ultra sound.

Industry
PROJECT NUMBER • 2015-702
PROJECT STATUS:
COMPLETED

Seafood CRC: A Final Seafood Omnibus: Evaluating changes in consumers attitudes and behaviours

The purpose of this project was twofold – firstly, to identify changes in consumers’ attitudes and behaviours over the past 5 years, and secondly, to further explore key issues impacting continued consumer trends. This study is the third Omnibus Consumer Research project carried out by...
ORGANISATION:
University of the Sunshine Coast (USC)
Environment
PROJECT NUMBER • 2012-020
PROJECT STATUS:
COMPLETED

The influence of fish movement on regional fishery production and stock structure for South Australia's Snapper (Chrysophrys auratus) fishery

From 2007 onwards, South Australia’s snapper (Chrysophrys auratus) fishery underwent significant and unprecedented changes that impacted on the management of the fishery. This ultimately reflected our poor understanding of the movement behaviour of snapper and its consequences for...
ORGANISATION:
SARDI Food Safety and Innovation
SPECIES
Industry
PROJECT NUMBER • 2002-239
PROJECT STATUS:
COMPLETED

Rock Lobster Post Harvest Subprogram: the effect of on-board cold water stunning on the survival and growth of caught and returned western rock lobsters (Panulirus cygnus)

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...
ORGANISATION:
Geraldton Fishermen's Co-operative Ltd
People
PROJECT NUMBER • 1999-336
PROJECT STATUS:
COMPLETED

Fish movement and migration - an ASFB workshop

Through the generous support of FRDC and State, Territory and Commonwealth fishery agencies, the Australian Society for Fish Biology (ASFB) has hosted a national workshop series since the early 1980's with eminent local and overseas scientists presenting keynote addresses on major themes. ...
ORGANISATION:
Australian Society For Fish Biology Inc
Environment
PROJECT NUMBER • 2017-109
PROJECT STATUS:
COMPLETED

Development of Fish Health Indicators for the Gladstone Harbour Report Card

As the link between land and sea environments, estuaries are complex ecosystems vulnerable to human impacts, which directly and indirectly affect plants and animals, including fish. Fish are key biological indicators of environmental contamination, as they are water breathers, common in aquatic...
ORGANISATION:
CQUniversity (CQU) Gladstone
Environment
Industry
View Filter

Organisation