2012 Conference Adelaide

ASFB 2012 Conference Adelaide

Program & Abstracts ASFB & OCS 2012 Joint Conference & Symposium Sebel Playford Hotel, Adelaide, South Australia

15-18 July 2012 Platinum Sponsor

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2 ASFB & OCS 2012 Joint Conference & Symposium Sebel Playford Hotel, Adelaide, South Australia 15-18 July 2012

ASFB 2012 Conference Adelaide

Contents Welcome

4

Organising Committee

4

Sponsors

5

General Information

6

Information for Presenters

6

Social Events

6

Associated Meetings and Workshops

7

Program Outline

8

Symposium and Conference Program

9

Keynote Speaker Biographies AND Abstracts

17

AWARD PRESENTATIONS

27

Oral Abstracts

28

Poster Abstracts

74

List of Poster Presentations

75

List OF PARTICIPANTS

86


WELCOME On behalf of the South Australian organising committee, it is my pleasure to welcome all delegates to Adelaide for the Australian Society for Fish Biology and Oceania Chondrichthyan Society Joint Conference and Symposium. I extend a particular welcome and early expression of appreciation to our plenary speakers, session chairs, sponsors and trade exhibitors. The Australian Society for Fish Biology (ASFB) and Oceania Chondrichthyan Society (OCS) normally hold separate annual conferences. This is the first time since the formation of the OCS in 2005 that the two organisations have agreed to hold a fully integrated, joint meeting. The conference organising committee decided on this joint approach to facilitate interaction and exchange of ideas amongst scientists and natural resource managers who may be doing similar research work, but because they work on different taxa that are represented by the two different organisations, never get a chance to meet and exchange ideas. In this meeting we will bring together a diversity of scientists who work on the taxonomic range of fishes, including chondrichthyans, from across the broad range of ecosystems from freshwater to marine throughout the Australasian region. The three-day meeting has two primary components. The conference component consists of a plenary session, several concurrent sessions as well as a poster session. The former involves the 2011 winners of several awards across the two organisations, including the K. Radway Allen Award and the Inaugural Early Career Excellence Award for the ASFB and the Passions of Paradise Student Research Grant for the OCS. The concurrent oral sessions and poster session provide opportunity for all delegates to present on any topic of their choice for their study species. The concurrent sessions also include a mini-symposium entitled ‘Fisheries genetics – what managers really want?’ that is aimed at evaluating the role of genetics in the management of wild fisheries. The second component of the meeting is a focussed symposium on the major topic of ‘Addressing the challenges of understanding the movement patterns of aquatic animals and their significance’. This symposium involves three plenary sessions during which nine eminent scientists will give keynote presentations on different themes that relate to fish movement, based on their research experiences. We are extremely honoured that Dr Steven Campana from Canada accepted the invitation to be our international plenary speaker. He is a world leader and innovator in his approaches to research on the movement and stock structure for a diversity of taxa including fish and shark species. Our eight Australian keynote speakers are recognised as experts in their particular fields and all have significant international reputations. Movement was chosen as the topic of this symposium as it is an aspect of the life history and population biology of all aquatic species that must be understood in order to develop the most appropriate natural resource management protocols. The study of movement is difficult and challenging and has resulted in the development of a number of different technological approaches. These approaches, the results and understanding that they have produced and their associated issues are the focus of the symposium. We hope that you find the scientific program stimulating and beneficial and that you enjoy the social events that we have organised. Also, whilst you are here we hope that you might take the opportunity to explore Adelaide and its surroundings and enjoy what they have to offer.

Tony Fowler Chair, Organising Committee ORGANISING COMMITTEE Tony Fowler, South Australian Research and Development Institute Katherine Cheshire, Australian Bureau of Agricultural and Resource Economics and Sciences, Department of Agriculture, Fisheries and Forestry Bronwyn Gillanders, University of Adelaide Charlie Huveneers, Flinders University/ South Australian Research and Development Institute Chris Izzo, University of Adelaide Stephen Mayfield, South Australian Research and Development Institute Lara Birchby (Meeting Manager)

ASFB OCS 2012 SECRETARIAT Lara Birchby The Meeting People Pty Ltd PO Box 882 Unley South Australia 5061 Tel: 08 8272 7005 (within Australia) +61 8 8818 7005 (International) Fax: 08 8272 7006 (within Australia) +61 8 8272 7006 (International) Email: [email protected]



Poster Presenter Information Attended authors discussions will take place on Tuesday 17 May during the afternoon tea from 15:45 – 17:30. Your poster number can be determined from the listing after the main program. Please note that you or one of your fellow authors will be required to be present at your poster during the dedicated viewing session to answer any questions.

GENERAL INFORMATION Venue The Meeting will be held from Sunday 15th to Wednesday 18th July 2012 at the Sebel Playford Adelaide. Sebel Playford Adelaide !120 North Terrace Adelaide !South Australia T: 08 8213 8888

The posters will be on display for the duration of the meeting and can be put up from 4.00 pm on Sunday 15 July but must be removed by the end of afternoon tea on Wednesday.

Conference Rooms and Refreshment Breaks The Plenary Session will be held in the combined Ballroom 2 & 3 and the concurrent sessions will be held in Ballroom 2, Ballroom 3 and Adelaide 1/2. Posters, the exhibition and all catering breaks will all be held in Ballroom 1.

Posters must fit a poster display space of 1 metre wide x 1.2 metres high including the heading. Velcro tabs will be provided to fix your poster to the board – pins must not be used.

Registration desk The registration desk will be located on the mezzanine level outside the meeting rooms at the Sebel Playford Adelaide and will be open for the duration of the meeting. Registration will start on Sunday 15 July and will be open from 4 pm – 8 pm. The registration desk will open from 8 am from Monday to Wednesday. If you have any queries during the meeting, please contact the Meeting Manager, Lara Birchby on 0411 439 410.

SOCIAL EVENTS Welcome Reception Date: Sunday 15 July 2012 Time: 5 pm – 7 pm Venue: Ballroom, Sebel Playford Adelaide Cost: Included with full and student registration. Extra tickets: $55 per ticket.

Climate The mean maximum daily temperature for this time of year in South Australia is around 14-18°C, the minimum temperature around 6-10°C during the night.

A great networking opportunity that will allow you to catch up with colleagues and mingle with delegates attending the meeting. The welcome reception will be held at the conference venue, the Sebel Playford Adelaide, and will feature some great South Australian wines.

Banks Banks are generally open from Monday to Friday from 9.30am - 4.00pm. Automatic Teller Machines (ATMs) are widely available.

Included in full and student registration. Additional tickets for accompanying persons can be purchased at $55. Student Function Date: 17 July 2012 Venue: Mansions, 21 Pulteney Street, Adelaide Time: 6.30 pm onwards Cost: Included with student registration. The Mansions is a 10 minute walk from the conference venue and should you wish to join a group that will walk from the venue, please meet in the main foyer of the Sebel Playford at 6.15 pm.

Local transport The Adelaide Airport is a twenty minute drive from Adelaide’s CBD. A taxi from the Adelaide Airport will cost approximately $20 (7.5kms). Suburban Taxi 131 008 Yellow Cabs 132 227 Adelaide Independent Taxi 132 211 Car parking Short term car parking is available near to the Sebel Playford Adelaide in the hotel carpark located opposite the hotel in Victoria Street. Rates are: • Self Parking – $18 per 24 hour • Delegate Parking – $15 maximum ($3 per hour)

Conference Dinner Date: Wednesday 18 July 2012 Time: 7 pm – 11.30 pm Venue: Adelaide Oval Function Centre Cost: Included with full and student registration. Extra tickets: $120 per ticket.

INFORMATION FOR PRESENTERS

The conference dinner will be held at Members Dining Room at the prestigious Adelaide Oval located over the Torrens River approximately 10 minutes walk from the Sebel Playford Adelaide. Tickets will be $120 per person and include dinner, drinks and entertainment. NB This function is included in the full and student registration.

Speaker Preparation Room The Speaker Preparation Room will be located in Adelaide 3 from Sunday 15 July – Wednesday 18 July at the following times: Sunday 15 July 16:00 – 19:00 Monday 16 July 07:00 – 17:00 Tuesday 17 July 08:00 – 17:00 Wednesday 18 July 08:00 – 16:00

The Adelaide Oval is a 10 minute walk from the conference venue and should you wish to join a group that will walk from the venue, please meet in the main foyer of the Sebel Playford at 6.15 pm. Due to the current renovations to the Adelaide Oval, the entrance to the Adelaide Oval Function Centre will be from the Northern gate which is accessed from Pennington Terrace. Parking is also available on the street at Pennington Terrace and within nearby streets.

Data projectors for Microsoft PowerPoint (ONLY) will be provided in all main oral session rooms. You will need to prepare your slides using PowerPoint. All speakers must check into the Speaker Preparation Room prior to your presentation. At that time, you may review your slides


ASSOCIATED MEETINGS AND WORKSHOPS Sunday 15 July 2012 3.00 pm – 5.00 pm

ASFB Executive Meeting, Adelaide Room 1

3.00 pm – 5.00 pm

OCS Executive Meeting, Adelaide Room 2

Monday 16 July 2012 5.30 pm – 7.30 pm

ASFB Committee Meetings

5.30 pm – 7.30 pm

OCS AGM, Adelaide Rooms 1/2

Tuesday 17 July 2012 12.45 pm – 2.15 pm

ASFB AGM, Ballroom 3

WORKSHOPS 1. Routine Fish Ageing (Invitation only) This workshop will continue the process that was begun at a similar workshop held at the ASFB annual conference last year in Townsville, towards developing a National Framework for routine fish age estimation from otoliths. The goal for developing the National Framework is to provide a unified set of Best Practise standards for a range of different levels of resourcing available, in order to produce reliable fish age data for ongoing fishery monitoring and stock assessments. Ultimately, the National Framework is planned to be made available as an on-line resource that has facility to exchange otolith images, contact information, and other material to promote increased collaboration and improved age estimation quality control standards nationwide. This workshop will be held at the South Australian Aquatic Sciences Centre, West Beach, on Thursday 19th July 2012. The organisers are Ross Marriott ([email protected]) and Jonathon Staunton-Smith ( [email protected]). 2. AATAMS workshop Following the ASFB/OCS joint conference, AATAMS and the University of Adelaide are hosting the first workshop introducing the new National AATAMS database. This database has been developed in the last 3 years under the guidance of acoustic telemetry users to provide a global database for the whole Australian acoustic community. During the workshop, members of the AATAMS data sub-committee will summarise the evolution of AATAMS and the database and present in detail the benefits of uploading data and using the AATAMS database. By the end of the workshop, you will know how to upload data, download data from AATAMS receivers, and use some of the tools offered by the database. We also strongly recommend that you bring you own data which you can enter during the workshop with the help of the people who developed the database at hand. Benefits of the database includes: - Access to data held by the community (example of what the database can provide will be presented); - Access to data collected by the 700+ receivers deployed and maintain by AATAMS; - Storage and archiving of all your data and metadata; and - Various tools developed for the AATAMS database including visualisation tools of receivers and detections. The workshop will be held the day after the conference on Thursday 19th of July 2012 at the University of Adelaide. For more information and to register your interest, please email Charlie Huveneers ( [email protected]). 3. Introduction to backpack electrofishing This is a two-day introductory course to backpack electrofishing that will be run by Smith-Root biologist Lisa Harlan. This course will be held on the 19th and 20th July 2012. Day one will entail an eight hour classroom session, whilst day two will involve a field trip to a nearby aquatic system for a practical session with the equipment.


8

ASFB & OCS 2012 Joint Conference & Symposium Sebel Playford Hotel, Adelaide, South Australia 15-18 July 2012

17:00-19:00 Welcome Reception

15:00 Registration Opens ASFB & OCS Executive Meetings

Sunday 15 July

Otoliths 1

Ecosystems/ Conservation 1

Movement 1

17:30-19:30 OCS AGM

Freshwater Fish Biology & Ecology 1

17:30-19:30 ASFB Committee Meeting

Sponsored by FRDC

Fishery Management 3

15:15-15:45 Afternoon Tea 15:45-17:30 Concurrent Session 3

Sponsored by FRDC

13:45-15:15 Concurrent Session 2 Fishery Otoliths/Ageing Larval Fish Management 2

12:45-13:45 Lunch

Sponsored by FRDC

Fishery Management 1

10:45-11:15 Morning Tea 11:15-12:45 Concurrent Session 1

08:30 Opening Ceremony 09:00-10:45 Plenary Session 1 09:00 Steven Campana 09:45 Greg Jenkins 10:15 Alison King

Monday 16 July

ASFB OCS 2012 PROGRAM OUTLINE !

Freshwater Fish Biology & Ecology 2

Genetics

Mansions

18:30-20:00 Student Mixer

!

Sponsored by Wildlife Computers

Lunch ASFB AGM 14:15-16:00 Concurrent Session 5 Marine Movement Genetics/ Fish 2 General Biology & Ecology 2 16:00-17:30 Afternoon Tea including! Poster Session

Marine Fish Biology & Ecology 1 12:30-14:15

09:00-10:30 Plenary Session 2 09:00 Jayson Semmens 09:30 John Koehn 10:00 Jenny Ovenden 10:30 President’s Poster Perspective 10:35-11:00 Morning Tea! 11:00-12:30 Concurrent Session 4

Tuesday 17 July

Sponsored by WA Fisheries Adelaide Oval Members Dining Room

Marine Ecosystems/ Recreational Fish Conservation Fishing Biology 2 & Ecology 4 19:00-23:30 Conference Dinner

13:30-15:15 Concurrent Session 6 Marine Freshwater Movement Fish Fish Biology 3 Biology & Ecology 3 & Ecology 3 15:15-15:45 Afternoon Tea! 15:45-17:15 Concurrent Session 7

12:30-13:30 Lunch

10:30-11:00 Morning Tea! 11:00-12:30 ASFB/OCS Plenary 11:00 Rod Lenanton 11:30 Rebecca Fisher 12:00 Cassie Rigby 12:15 Martin Gomon

09:00-10:30 Plenary Session 3 09:00 Craig Mundy 09:30 Colin Simpfendorfer 10:00 Simon Goldsworthy

Wednesday 18 July

Sunday 15 July 2012 15:00-19:30 15:00-17:00 17:00-19:00

Registration Opens ASFB Executive Meeting Welcome Reception

Adelaide Room 1

OCS Executive Meeting

Foyer Adelaide Room 2 Ballroom 1

Monday 16 July 2012 08:00 08:30 08:30 08:40

09:00-10:45 09:00

Registration Opens Foyer Opening Ceremony Ballroom 2/3 Chair: Bronwyn Gillanders Welcome – Bronwyn Gillanders and Susan Theiss Official Opening – by the Honourable Lyn Breuer MP, Speaker of the House of Assembly, representing the Premier of South Australia.! Plenary Session 1 Chair: Tony Fowler Murray Darling Basin Authority Keynote Speaker Natural tags and markers for tracking and identifying aquatic organisms Steven E. Campana

Ballroom 2/3

09:45

Understanding the dispersal of marine fish larvae: how far have we come and where to next? Greg Jenkins

10:15

Not just “Goin’-with-the-Flow”: challenges in understanding the movement patterns of the early life stages of Australian freshwater fish Alison King

10:45-11:15 11:15-12:45

Morning tea Concurrent Session 1 C1:1 Fishery Management 1 Chair: Gavin Begg Sponsored by FRDC

Ballroom 1/Foyer

C1:2 Otoliths 1 Chair: Jodie Kemp Ballroom 2

Ballroom 3

C1:3 Ecosystems/ Conservation 1 Chair: Colin Simpfendorfer Adelaide Rooms 1/2

11:15

Predicting common Banana Prawn potential catch in Australia’s Northern Prawn Fishery Rik Buckworth, Emma Lawrence, Bill Venables, Peter Rothlisberg, Trevor Hutton and Fiona Hill

Otolith shape and elemental composition: Complementary tools for stock discrimination of mulloway (Argyrosomus japonicus) in Southern Australia Greg J. Ferguson, Tim M. Ward and Bronwyn M. Gillanders

Environmental Water Allocations in regulated lowland rivers may encourage offstream movements and spawning by common carp, Cyprinus carpio: implications for wetland rehabilitation. Anthony J. Conallin, Ben B. Smith, Leigh A. Thwaites, Keith F. Walker and Bronwyn M. Gillanders

11:30

Modelling the larval dispersal and recruitment of western king prawns, Penaeus latisculcatus, to nursery grounds in Spencer Gulf, South Australia Mark Doubell, John Luick, John Middleton, Charles James, Cameron Dixon and Shane Roberts

Contribution of water and diet to otolith chemistry in freshwater fish Zoë A. Doubleday, Christopher Izzo and Bronwyn M. Gillanders

Links between fish assemblages and natural, modified and restored riparian zones Travis Howson

11:45

Improving the approach for adoption of technological development in the fishing industry: by-catch reduction in the Gulf St Vincent demersal prawn trawl fishery Cameron Dixon, Nathan Bicknell, Daniel Gorman, Graham Hooper, Craig Noell and Shane Roberts

River reconstructions: Inferring past, present and future riverine conditions based on golden perch sclerochronologies Christopher Izzo, Zoë A. Doubleday and Bronwyn M. Gillanders

Atlantis ecosystem modelling in the southern Benguela Michael D Smith, Beth Fulton and Rob Day

12:00

Research and development of novel by-catch reduction technologies in a demersal trawl fishery Daniel Gorman, Nathan Bicknell, Cameron Dixon, Graham Hooper and Shane Roberts

Spatial distribution of adult coralreef fish populations that are replenished by seagrass nurseries, as revealed by otolith stable isotope signatures CM Huijbers, Ivan Nagelkerken, AO Debrot and E Jongejans

Differences in fish assemblages associated with wrack on sandy beaches between storm and calm events in Southern Australia. Ryan Baring, Peter Fairweather and Rebecca Lester


Ballroom 2/3

Monday 16 July 2012 continued… 12:15

Estimating cryptic mortality for NZ sea lions using crash tests and video: Australia-NZ liaisons Edward Abraham, Robert Anderson, Martin Cryer, Rohan Currey, Jeremy Lyle and Giulio Ponte

Validation of age and backcalculation of growth from otoliths of early life history phase Purplespotted gudgeon, Mogurnda adspersa Danswell Starrs, Brendan Ebner and Christopher Fulton

Is small adequate? Assessing the movement of eastern blue gropers (Achoerodus viridis) to determine the adequacy of protection in a small marine reserve Kate Lee, Charlie Huveneers and Rob Harcourt

12:30

Success of an industry Code of Practice in mitigating interactions of a fishery with a protected species: can industrybased, real-time monitoring programs reduce or eliminate discrepancies between observer and logbook data? Tim Ward

Spatial grouping and temporal trends in otolith chemistry of an estuarine fish Ana Judith Giraldo, Travis S. Elsdon and Bronwyn M. Gillanders

12:45-13:45 13:45-15:15

Lunch Concurrent Session 2 C2:1 Fishery Management 2 Chair: Sean Sloan Sponsored by FRDC

Redmap: an online database and mapping resource for observational marine species data – marine monitoring, community engagement and collaborative research effort Gretta T Pecl, Jemina StuartSmith, Dianne Bray, Karen Edyvane, Stewart Frusher, Gary Jackson, Natalie Moltschaniwskyj, Melissa Nursey-Bray, Keith Rowling, Marcus Sheaves and Peter Walsh Ballroom 1/Foyer

C2:2 Otoliths/Ageing Chair: Chris Izzo

C2:3 Larval Fish Chair: Jian Qin

Ballroom 2

Adelaide Rooms 1/2

From theory to policy: implementing spatial management to a blacklip abalone fishery in South Australia Stephen Mayfield, Lianos Triantafillos and Andrew Hogg

Interactive effects of environment and genetics on the otolith chemistry of a temperate estuary associated sciaenid, mulloway (Argyrosomus japonicus) Thomas C. Barnes and Bronwyn M. Gillanders

Food competition and resource partitioning amongst King George Whiting and other fish species at a nursery ground Craig A. Meakin, Jian G. Qin and Anthony J. Fowler

14:00

Measuring population change – comparison of blacklip abalone survey density estimates before and after commercial fishing Rowan C. Chick, Stephen Mayfield, Paul Burch, Sacha N. Turich and Richard McGarvey

Connecting Fish – Using otolith elemental fingerprints to determine the contributions of estuaries to coastal populations over time Patrick Reis-Santos, Susanne E. Tanner, Rita P. Vasconcelos, Travis S. Elsdon, Henrique N. Cabral and Bronwyn M. Gillanders

Swimbladder ontogeny and environmental factors regulating larval fish function Lindsey Woolley and Jian G. Qin

14:15

Should South Australia’s garfish fishery be managed through exclusive regulation of gear, strategic effort reduction, or a combination of both? Mike Steer, Rick McGarvey and Tony Fowler

Long-term otolith biochronologies reveal the effects of environmental variation and stock abundance on tiger flathead growth rates John Morrongiello

Food and feeding ecology of Snapper larvae Jian G. Qin

14:30

Requirements for comanagement in abalone fisheries Rob Day, Patrick Gilmour, Jeremy Prince and P. Dwyer

Can spatial differences in the chronological structure of otoliths provide insight into the origins and large-scale movement of Snapper (Pagrus auratus)? Anthony Fowler and Michael Steer

Gut histological change of Yellowtail Kingfish larvae during weaning Ben Nan Chen, Zhenhua Ma, Wayne Hutchinson, Jian G. Qin, Jennifer Cobcroft, Steven Battaglene and Mike S. Thomson

14:45

Using a capture-recapture model to estimate natural mortality of lobsters in a marine reserve Paul Burch, Simon Wotherspoon and Stewart Frusher

Age and growth of the Pelagic Thresher (Alopias pelagicus) and the Scalloped Hammerhead (Sphyrna lewini) in the eastern Indian Ocean Michael Drew, Charlie Huveneers, William White and Dharmadi

Exploration of optimum temperature regimes for Yellowtail Kingfish larvae Wayne Hutchinson, Zhenhua Ma, Ben Nan Chen, Jian G. Qin and Mike S. Thomson

13:45

Ballroom 3



15:15-15:45 15:45-17:30

Afternoon Tea Concurrent Session 3 C3:1 Fishery Management 3 Chair: Keith Rowling Sponsored by FRDC Ballroom 3

Age, growth and reproductive biology of Australian blacktip shark, Carcharhinus tilstoni, from the Great Barrier Reef Marine Park Alastair V Harry, Colin A Simpfendorfer and Andrew J Tobin

Growth, survival and food consumption of Yellowtail Kingfish larvae at different food densities Zhenhua Ma, Jian G. Qin, Wayne Hutchinson and Ben Nan Chen Ballroom 1/Foyer

C3:2 Freshwater Fish Biology & Ecology 1 Chair: Qifeng Ye

C3:3 Movement 1 Chair: Paul Rogers Adelaide Room 1/2

Ballroom 2

Capitalising on seasonal biology of greenlip abalone (Haliotis laevigata): advantages of a closed season in an Australian abalone fishery Ben Stobart, Stephen Mayfield and Richard McGarvey

Estimating fish species richness from underwater video and netting in remote Australian waterholes Brendan C. Ebner and David L. Morgan

A method for addressing the issue of auto-correlation in telemetry data: Evaluating environmental influences on the spatial ecology and spawning behaviour of an estuarine-dependent fish, Macquaria colonorum C. T. Walsh, I. V. Reinfelds, Matthew C. Ives, C. A. Gray, R. J. West and D. E. van der Meulen

16:00

Status of Australian herring – a weight-of-evidence assessment Kim Smith

Resilience, Resistance and Fish Movement in Lake Eyre Basin Dale McNeil, David Schmarr and Rupert Mathwin

Eel-tailed catfish (Tandanus tandanus) – critical dispersers or curious explorers? Bernie Cockayne, Kate Burndred, Jonathan Marshall, James Fawcett and David Sternberg

16:15

Simultaneous estimation of sizeselectivity parameters for multiple fishing gears Athol R. Whitten

Stuck in the Middle with you? Illuminating diadromy in an impacted catchment Rupert Mathwin, David Schmarr and Dale McNeil

The role of spatial ecology in the conservation management of Macquarie perch in the ACT. Ben Broadhurst, Mark Lintermans, Brendan Ebner, Jason Thiem, Katie Ryan, Rhian Clear and Danny Wright

16:30

The underlying dynamics of a simple CPUE based fisheries harvest control rule Malcolm Haddon and Natalie Dowling

2012: A Cooper Odyssey David Schmarr, Rupert Mathwin and Dale McNeil

Tracking broad-scale movements of a top-order predator using coastal sensor arrays and satellite telemetry. Russell Bradford and Barry Bruce

16:45

Length-based empirical estimation of SPR for smallscale, data-poor fisheries Adrian Hordyk, Neil Loneragan and Jeremy Prince

Angry when outnumbered: Behavioural aggression in Gambusia holbrooki is conditional upon temperature and relative abundance Jessica Pink, Andy Moore, Tyrie Starrs, Mark Lintermans and Christopher J. Fulton

On movement of Western Australian sharks Matias Braccini, Rory McAuley and Michael Moran

17:00

Mixing and matching – establishing harvest strategies in a multi-species mud-cockle fishery Jay Dent, Stephen Mayfield, Craig Noell, Paul Burch, Dan Gorman and Tim Ward

Habitat associations of native fish larvae in the main channel of a heavily regulated river system, Australia Katherine J. M. Cheshire, Qifeng Ye, Bronwyn M. Gillanders and Alison J. King

Habitat use, movement patterns and residency of greenback flounder (Rhombosolea tapirina) in the Murray River estuary and Coorong, South Australia Jason Earl, Anthony Fowler, Qifeng Ye and Sabine Dittmann

15:45



Understanding the animal ethics application process: some hints for expediency. Stephen Balcombe

17:30-19:30 17:30-19:30

ASFB Committee Meetings OCS AGM

Complex behavioural patterns of the Australian Lungfish (Neoceratodus forsteri) within an impounded river system. David Roberts, Sebastian Knight, Michele Burford and Mark Kennard

Movement and connectivity in populations of adult Golden perch Macquaria ambigua in two lowland rivers, Australia Wayne Koster, David Crook and David Dawson Adelaide Rooms 1/2

Tuesday 17 July 2012 09:00-10:35 09:00

Plenary Session 2 Ballroom 2/3 Chair: Susan Theiss Where, when, how and why: Using acoustic telemetry to understand marine animal movement, behaviour and physiology Jayson Semmens

09:30

Tagging freshwater fish John Koehn, Jarod Lyon, Wayne Koster and Matthew Jones

10:00

Crinkles in connectivity: a genetic perspective on the influence of movement on fisheries stock structure Jennifer R. Ovenden

10:30

President’s poster perspective Bronwyn Gillanders

10:35-11:00 11:00-12:30

Morning tea Concurrent Session 4 C4:1 Marine Fish Biology & Ecology 1 Chair: Alastair Harry

C4:2 Freshwater Fish Biology & Ecology 2 Chair: Jarod Lyon

Ballroom 3

Ballroom 2

Fish movement at the terminus of the Murray-Darling Basin: past, present and future fish passage at the Murray Barrages Christopher M. Bice, Brenton P. Zampatti and Paul R. Jennings

The management of native freshwater fish in Australia: what has genetics brought to the table? Andy Moore

11:15

House or Home? How snapper (Chrysophrys auratus) utilise artificial and natural reefs in Port Phillip Bay. Kade Mills, Paul Hamer, Gerry Quinn and Daniel Ierodiaconou

From drought to flood: fish assemblage response to freshwater flows in the Coorong Qifeng Ye, Luciana Bucater and David Short

How genetics supports decision-making about the harvesting of wild fisheries Jennifer R. Ovenden, Oliver Berry, David J. Welch, Rik C. Buckworth and Cathy M. Dichmont

11:30

Research into the life history characteristics and fishery of teraglin, Atractoscion aequidens, (Family: Sciaenidae) off the coast of New South Wales, Australia. Anne-Marie Hegarty, William Gladstone and John Stewart

"Hi. My name is Murray; Murray Hardyhead." .... A novel approach to increasing community awareness about threatened species management. Michelle Kavanagh

Stakeholder views of the use of genetic tools in fisheries management David J. Welch, Rik C. Buckworth, Jennifer R. Ovenden, Oliver Berry and Cathy M. Dichmont

11:45

Status of knowledge on the Mobulidae and conservation issues Lydie I.E. Couturier, Andrea D. Marshall, Fabrice R.A. Jaine, Tom Kashiwagi, Simon J. Pierce, Kathy Townsend, Scarla J. Weeks, Mike B. Bennett and Anthony J. Richardson

Invasives and rehabilitation of freshwater systems carp acoustics: Attractants and repellents Leigh Thwaites and Josh F. Fredberg

Close kin relationships provide a fishery independent approach for estimating Southern Bluefin Tuna spawning stock biomass Peter Grewe, Mark Bravington, Campbell Davies, Peta Hill, Rasanthi Gunasekera and Danielle Lalonde

11:00

Embryonic diapause in the elasmobranchs Daniela Waltrick, Colin Simpfendorfer and Cynthia Awruch

Ballroom 1/Foyer

C4:3 Genetics Chair: Rik Buckworth Adelaide Rooms 1/2


Tuesday 17 July 2012 continued… 12:00

Size and age compositions and growth of King George Whiting (Sillaginodes punctata) in southwestern Australia Elena H. Sulin, Alex S. Hesp, Norman G. Hall and Jennifer A. Chaplin

Investigating the effects of intraand inter-specific competition between native and introduced fish using RNA:DNA ratios as a biochemical indicator of condition Peter Fraser, Christopher Izzo and Bronwyn Gillanders

Contrasting evolutionary histories for sister species of Australian Salmon Glenn I. Moore and Jennie A. Chaplin

12:15

Reproductive biology of the Greeneye spurdog (Squalus chloroculus) on the continental slope off south!eastern Australia Bastien Rochowski

Genetic effective population size and census size ratios for elasmobranchs Christine Dudgeon, Dean Blower and Jennifer Ovenden

12:30-14:15

Lunch ASFB AGM Concurrent Session 5 C5:1 Marine Fish Biology & Ecology 2 Chair: Gary Jackson

Do invasive eastern gambusia (Gambusia holbrooki) shape wetland fish assemblage structure in south-eastern Australia? Jed Macdonald, Zeb Tonkin, David Ramsey, Andrew Kaus, Alison King and David Crook

14:15-16:00

14:15

Ballroom 3

Ballroom 1/Foyer Ballroom 3

C5:2 Movement 2 Chair: Christine Dudgeon Ballroom 2

C5:3 Genetics/ General Chair: Andy Moore Adelaide Rooms 1/2

Can a threshold value be used to classify Chondrichthyan reproductive modes: review and validation using an oviparous species, Heterodontus portusjacksoni Holly Frazer

Beware the shark in the sun: Investigations into the approach behaviour of white sharks, Carcharodon carcharias, to cagediving baiting operations Dirk Holman, Alex H. Taylor, Rachel Robbins, Andrew Fox and Charlie Huveneers

Linking demography and genomics of eastern Australian sea mullet (Mugil cephalus) for management and conservation Nils Krück, Eric Treml, David Innes, Ian Tibbetts and Jenny Ovenden

14:30

Might diet contribute to spatial variation in growth for Snapper (Pagrus auratus) in South Australian gulf waters? Matthew Lloyd, Anthony Fowler and Bronwyn Gillanders

Use of acoustic monitoring to assess post-release survival and movement of gummy shark (Mustelus antarcticus) and southern fiddler ray (Trygonorrhina dumerilii) after capture stress Camila Martins, Richard Reina and Terence Walker

Blacktip Hybrid Sharks: An update Jess A.T. Morgan, Malcolm Keag, John Kirkwood and Jennifer R. Ovenden

14:45

Indicator fatty acids in multiple shark tissues and blood serum resulting from different artificial pellet diets Crystal Beckmann, Jim G. Mitchell, Laurent Seuront, David Stone and Charlie Huveneers

Home range and movement of Centrophorus zeehaani on the continental slope off South Australia determined by acoustic telemetry Ross Daley

Do stocking practices influence Rainbow Trout growth in a New Zealand lake? A bioenergetic assessment Jennifer M. Blair, Brendan J. Hicks, Rob Pitkethley, Nick Ling, Ilia Ostrovsky and David Rowe

15:00

Empty slums and crowded mansions: scaling up cryptic density dependence in temperate reef fish John R Ford, Jeffery S Shima and Stephen E Swearer

Acoustic freshwater fish tracking programs: How managers use this technology to inform their decision making John Conallin, Lee Baumgartner, Ian Wooden and Wayne Robinson

Stocking of sturgeons: Preparing Huso huso juveniles for release into estuarine waters Nastaransadat Mazloumi

15:15

Unusual fatty acid profiles of manta rays and whale sharks suggest they might not predominantly feed on crustacean zooplankton Lydie I.E. Couturier, Christoph A. Rohner, Anthony J. Richardson, Simon J. Pierce, Andrea D. Marshall, Fabrice R.A. Jaine, Kathy Townsend, Mike B. Bennett, Scarla J. Weeks and Peter D. Nichols

Combining visual census and ultrasonic telemetry for markresight experiments Cesar Penaherrera-Palma, Stewart Frusher, Alex Hearn, Alistair Hobday, Jayson Semmens and Eduardo Espinoza

Effects of salinity on the growth and osmoregulation of Yellowtail kingfish (Seriola lalandi) David Stone, Shane D. Roberts, Marty Deveney and Craig Hayward


Tuesday 17 July 2012 continued… 15:30

Predicting the occurrence of whale sharks over entire ocean basins Ana Sequeira, Camille Mellin, Steven Delean, Mark G. Meekan and Corey J. A. Bradshaw

15:45

Diversity in Shark Nursery habitat along the central Great Barrier Reef coast Peter Yates, Michelle Heupel, Andrew Tobin and Colin Simpfendorfer

16:00-17:30 18:30-20:00

Spatial dynamics, diving behaviour and habitat use of satellite-tracked manta rays (Manta alfredi) in eastern Australia Fabrice R.A. Jaine, Scarla J. Weeks, Lydie I.E. Couturier, Michael B. Bennett, Kathy A. Townsend and Anthony J. Richardson

Livelihoods from Predators: Shark Fisheries in Eastern Indonesia Vanessa Jaiteh, Carol Warrena and Neil Loneragan

Determining fine-scale patterns of movement in black bream Acanthopagrus butcheri and estuary perch Macquaria colonorum within droughtaffected estuaries Joel Williams, Jeremy S. Hindell, Sean R. Tracey, Klaas Hartmann, Greg P. Jenkins and Steve E. Swearer Poster Session & afternoon tea – Sponsored by Wildlife Computers Student Mixer – Mansions, Pulteney Street

Ballroom 1

Wednesday 18 July 2012 09:00-10:30 09:00

Plenary Session 3 Ballroom 2/3 Chair: Charlie Huveneers Application of animal movement analytical techniques to fishery data: how do you turn a dataset with 25,000 dives and 10,000,000 records per year into meaningful information? Craig Mundy

09:30

Beyond the “shiny new hammer”: data analysis tools to make the most of acoustic monitoring studies Colin A. Simpfendorfer and Michelle R. Heupel

10:00

Impact and mitigation of Australian sea lion bycatch in the shark gillnet fishery off South Australia Simon Goldsworthy

10:30-11:00 11:00-12:30

Morning tea ASFB/OCS Joint Plenary Chair: Bronwyn Gillanders 2011 K. Radway Allen Award Some reflections of a lifetime in fishery science Rod C. Lenanton

11:00

11:30

2011 Inaugural Early Career Excellence Award Larval swimming performance and impacts on dispersal Rebecca Fisher

12:00

OCS-Passions of Paradise Student Research Grant Habitat associations of deepwater Chondrichthyan life history traits Cassie Rigby and Colin Simpfendorfer

12:15

Website Launch Fishes of Australia Martin Gomon

12:30-13:30 13:30-15:15

Lunch Concurrent Session 6 C6:1 Marine Fish Biology & Ecology 3 Chair: Malcolm Francis

C6:2 Freshwater Fish Biology & Ecology 3 Chair: Katherine Cheshire

Ballroom 3

Ballroom 2

13:30

Rain-induced reversal of activity rhythms in Yellowfin Bream Nicholas L. Payne, Ruan Gannon, Dylan E. van der Meulen, Jayson M. Semmens, Iain M. Suthers, Charles A. Gray and Matthew D. Taylor

Ballroom 1/Foyer Ballroom 2/3

Ballroom 1/Foyer

Monitoring the fish community of the Great Darling Anabranch in the 2010-11 flood Deborah Bogenhuber and Danielle Linklater

C6:3 Movement 3 Chair: Jayson Semmens Adelaide Rooms 1/2

Radio transmitters can affect the feeding behavior and the movement of freshwater stingrays (Myliobatiformes, Potamotrygonidae)? Domingos Garrone Neto, Carolina Bonfim Tiveron, Rafael dos Santos, Lisiane Hahn and Otto Bismarck Fazzano Gadig


Wednesday 18 July 2012 continued… 13:45

Distribution, relative abundance, and length of the vulnerable black cod Epinephelus daemelii in northern NSW Hamish Malcolm and David Harasti

Use of off channel lower ephemeral lakes in the Great Darling Anabranch system Danielle Linklater, Lauren Carr, Deborah Bogenhuber and Iain Ellis

Tagging fish in the Murray River – Lessons learnt Jarod Lyon, Justin O’Mahony and Charles Todd

14:00

Where are the little ones? Distribution and relative abundance of juvenile and subadult black cod Epinephelus daemelii in NSW David Harasti, Christopher Gallen, Hamish Malcolm and Patrick Teggart

Persistence of Spangled perch in the southern Murray-Darling Basin post 2011 flooding. Iain Ellis

Movement dynamics of translocated southern rock lobsters (Jasus edwardsii) in South Australia Adrian Linnane, Shane Penny, Matthew Hoare and Peter Hawthorne

14:15

Behavioural plasticity in coral reef fishes subject to a dynamic wave environment Siobhan J. Heatwole and Christopher J. Fulton

Fish community response to flooding at Lindsay Mulcra Wallpolla Islands, North-West Victoria David Wood

Post-release survival, pop-up satellite tag predation and vertical habitat use of school shark (Galeorhinus galeus) in the Great Australian Bight Paul J. Rogers, I. Knuckey, R. Hudson and L. Guida

14:30

Account of a mass aggregation of Port Jackson sharks (Heterodontus portusjacksoni) at Point Cooke Marine Sanctuary, Victoria, Australia Andrew Christie

Flow diversion effects on Murray cod in upland environments Mark Lintermans, Fiona Dyer, Anu Datta and Daniel Wright

The devil is in the detail: Tracking movements in the Southern Blue Devil (Paraplesiops meleagris) using photo-ID Simon Bryars

14:45

Morphological differences within sympatric populations of the sparid Pagrus auratus in New Zealand Darren Parsons, Mark Morrison and Kendall Clements

Freshwater catfish (Tandanus tandanus) response to reconnection events of Washpen Creek, a large, mid-murray paleochannel Lauren Carr, Rick Stoffels, Danielle Linklater and Rohan Rehwinkel

When do they move: Macquarie perch (Macquaria australasica) and the short finned eel (Anguilla australis) in the Yarra River, Victoria Charles Todd, Dave Crook and Nick Bond

15:00

Use of photo-identification to monitor white sharks aggregating at Stewart and Ruapuke Islands, New Zealand Clinton Duffy, Malcolm Francis, Kina Scollay and John Montgomery Afternoon tea Concurrent Session 7 C7:1 Marine Fish Biology & Ecology 4 Chair: Matias Braccini

Response of small-bodied fish to habitat reconnection in the Murray River Estuary, South Australia Luke Silvester, Sabine Dittmann and Kathleen Beyer

C7:2 Ecosystems/ Conservation 2 Chair: Simon Goldsworthy

C7:3 Recreational Fishing Chair: Kim Smith

Ballroom 3

15:15-15:45 15:45-17:15

15:45

16:00

Ballroom 1/Foyer

Are seasonal manta ray Manta alfredi aggregations related to zooplankton nutritional quality? Nathalie Verlinden, Luiz Felipe Mendes Gusmao, Lydie E. Couturier, Fabrice Jaine, Anthony Richardson, Michael Bennett, Scarla Weeks and Kathy Townsend

Ballroom 2

Recovering populations of the endangered fish red-finned blueeye, Scaturiginicthys vermeilipinnis, at Edgbaston Reserve in central western Queensland Adam Kerezsy

Adelaide Rooms 1/2

Behavioural thermoregulation by the world’s largest fish Michele Thums, Mark Meekan, John Stevens, Steven Wilson and Jeff Polovina

Oriental weatherloach, Misgurnus anguillicaudatus, in South Australia: a risk assessment Josh F. Fredberg and Leigh Thwaites

Overview of research on the recreational fishery for southern bluefin tuna in Tasmania. Sean R. Tracey and Jeremy M. Lyle

Recreational gillnetting in Tasmania – improving fishing practices through management intervention Jeremy M. Lyle and Sean R. Tracey


Wednesday 18 July 2012 continued… 16:15

The effects of shark cage diving on the localised and broad-scale movements of white sharks in Australian waters Barry Bruce and Russell Bradford

Decadal shifts in demersal fish assemblage structure in Port Phillip Bay correspond with drought and the introduction of an exotic starfish Alastair Hirst

Managing Murray cod: a large, iconic, threatened angling species John Koehn

16:30

Acoustic tracking of New Zealand white sharks reveals spatial preferences and smallscale movements in an island chain Malcolm Francis, Clinton Duffy, Warrick Lyon and Kina Scollay

Detecting snapper (Pagrus auratus) larval dispersal from a New Zealand marine reserve: preliminary results A. Croucher, Agnès Le Port, M. O’Sullivan and J.C. Montgomery

Integrated state-wide survey of boat-based recreational fishing catch and effort Brent Wise, Ken Pollock, Karina Ryan, Adrian Thompson, Norm Hall and Rod Lenanton, Gary Jackson

16:45

Assessing the effects of an electric deterrent on the behaviour of white sharks Charlie Huveneers, Paul J. Rogers, Jayson Semmens, Crystal Beckmann, Alison A. Kock, Brad Page and Simon Goldsworthy

The impact of marine closed areas on fishing yield under a variety of management strategies and stock depletion levels Belinda Barnes and Harvinder Sidhu

Do estuarine artificial reefs enhance fish biodiversity and recreational angling opportunities? Charles A. Gray, F. Ochwada-Doyle, M. Lowry and H. Folpp

17:00

Evaluation of shark detection rates by aerial observers William D. Robbins, Victor M. Peddemors and Steven J. Kennelly

Protecting the Harlequin Fish (Othos dentex) within South Australia’s new system of marine protected areas: Acoustic tracking to determine site fidelity and movement patterns Simon Bryars, Paul Rogers and David Miller

Monitoring the recreational take of shark species of relevance to Commonwealth fisheries Katherine Cheshire and Peter Ward

17:15 18:30 for 19:00-23:30

Sessions conclude Conference Dinner – sponsored by WA Fisheries Adelaide Oval Members Dining Room


Keynote biographies abstracts

&


KEYNOTE BIOGRAPHY AND ABSTRACT

International Keynote Speaker Dr Steven Campana! Bedford Institute of Oceanography , Nova Scotia Canada

Dr. Steven Campana is a Senior Scientist at the Bedford Institute of Oceanography in Canada and an Adjunct Professor at both Dalhousie University and the University of Windsor. He directs an active research program in fish population dynamics, with particular emphasis on the development of new technologies in support of age determination, stock discrimination, shark population dynamics and fish tracking. He currently heads both the Otolith Research Laboratory and the Shark Research Laboratory, leads a number of interdisciplinary multinational projects, and has published more than 200 primary and technical scientific papers.

Natural tags and markers for tracking and identifying aquatic organisms Steven E. Campana Population Ecology Division, Bedford Institute of Oceanography, Dartmouth, Nova ([email protected]) (http://www.marinebiodiversity.ca/otolith/english/home.htm)

Scotia,

Canada

A winning feature of naturally-induced markers is their simultaneous appearance on the entire group or population, at no expense to the researcher. The challenge then becomes the search for a marker that is sufficiently distinct that it will allow clear identification of the group of interest. Meristics and morphometrics sometimes allow discrimination of populations, but are usually less effective at the sub-population scale. Elemental and isotopic fingerprints, genetic markers, growth patterns recorded in calcified tissues, and parasites are all examples of natural tags with demonstrated success in identifying and tracking sub-populations, groups and even individuals of teleost fishes. Far less explored are similar applications involving elasmobranchs and aquatic invertebrates, yet many of the same powerful tracking and identification applications appear to exist for these taxa as well. In this talk, I will briefly review some of the established natural tags with proven track records for monitoring movement, before exploring some of the exciting possibilities involving novel tags and seldom-examined organisms.


KEYNOTE BIOGRAPHY AND ABSTRACT KEYNOTE BIOGRAPHY AND ABSTRACT Professor Greg Jenkins Department of Primary Industries, Victoria, Australia Professor Greg Jenkins Department of Primary Industries, Victoria, Australia

Greg Jenkins is the manager of the fish ecology program at the Fisheries Research Branch, Department of Primary Industries Victoria, and Professorial Fellow with the Department of Zoology, University of Melbourne. Over more than 20 years Greg has led a series of Australian Research Council and Fisheries Research and Development Corporation Greg Jenkins is exploring the manager the life fish history ecologyofprogram at in theparticular Fisheriesthe Research Branch, Primary funded projects the of early fish, and influence of theDepartment environmentof (climate, Industries Victoria, Professorial withand therecruitment Departmentsuccess. of Zoology, Melbourne. Over more 20 oceanography and and habitat) on larvalFellow ecology TheUniversity research of has made extensive use than of daily years led a series of Australian Research Council and Fisheries and Development Corporation otolith Greg rings has to investigate larval biology and dispersal. This information hasResearch been integrated into simulation models funded the early life historytoofstudy fish,larval and dispersal in particular influence of the environment (climate, includingprojects realisticexploring larval biology and behaviours andthe advection pathways. Recently the research oceanography and habitat) on larval ecology and success. The research has made extensive use relating of daily has been augmented with modern techniques suchrecruitment as otolith microchemistry and genetics to answer questions otolith rings and to investigate larval biology and has dispersal. Thispublication informationofhas been integrated into simulation models to dispersal connectivity. This research led to the approximately 80 papers in peer-reviewed including realistic larval biology and behaviours to study larval dispersal and advection pathways. Recently the research scientific journals. has been augmented with modern techniques such as otolith microchemistry and genetics to answer questions relating to dispersal and connectivity. This research has led to the publication of approximately 80 papers in peer-reviewed scientific journals. Understanding the dispersal of marine fish larvae: how far have we come and where to next? Greg Jenkins1,2 1 Fisheries Research Branch, Department of Primary Industries, Queenscliff, Victoria Australia 2 Understanding the dispersal of marine fish larvae: how far haveAustralia we come and where to next? Department of Zoology, University of Melbourne, Parkville, Victoria Greg Jenkins1,2 1 Fisheries Research Branch, of Primary Industries, Queenscliff, Victoria Australia Over the past forty years, ourDepartment understanding of dispersal of marine larvae has developed from a true “black box” where 2 Department Zoology, University Melbourne, Parkville, Victoria nothing was ofunderstood betweenofspawning and settlement or Australia recruitment, through to a relatively sophisticated understanding today based on a proliferation of research involving new technologies. Primary drivers for this rapid Over the past years,was ourthe understanding of dispersal marine larvae hasvariation developed a true “black box”and where proliferation offorty research need to understand and of predict recruitment for from fishery management, the nothing was understood between spawning settlement or recruitment, through to a relatively sophisticated need to understand larval connectivity for marineand protected area design and management. understanding today based on a proliferation of research involving new technologies. Primary drivers for this rapid proliferation of research was the to understand predict recruitment for fishery management, and the The discovery of daily rings in need otoliths, allowing theand estimation of pelagic variation larval duration (PLD), together with need to understand larvalbased connectivity for marineand protected areamodelling, design andallowed management. availability of computer hydrodynamic dispersal the first quantitative assessment of dispersal of marine fish larvae. Although early modelling studies generally treated larvae as passive particles, there was The discovery of daily rings inmigration otoliths, behaviour allowing the pelagic modelling larval duration (PLD), together with the increasing evidence of vertical that estimation significantlyofaffected outcomes. More recently larvae availability of computer basedshown hydrodynamic and dispersal modelling, particularly allowed theinfirst of of many species have been to be relatively strong swimmers, latequantitative stages, andassessment also to show dispersal ofswimming marine fish Although early of modelling studies cues. generally as passive particles, there was directional in larvae. response to a range environmental The treated realisedlarvae dispersal will also be influenced by increasing evidence of vertical migration significantly modelling outcomes. Morespecies recentlyrealised larvae larval mortality, mediated through factorsbehaviour such as that condition, growthaffected and predation. Finally, in many of many species have shown towith be suitable relativelysettlement strong swimmers, particularly in late stages, and also to show dispersal will depend on been the interaction sites. directional swimming in response to a range of environmental cues. The realised dispersal will also be influenced by larval mortality, factors suchdivided as condition, growth and and predation. Finally, in many species realised Recent researchmediated advancesthrough have been primarily between empirical modelling studies. Empirical studies have dispersal measurement will depend onofthe interaction withstable suitable settlement sites. included dispersal using isotope marking, DNA parentage analysis and otolith microchemistry. Modelling studies have seen the development of increasingly sophisticated biophysical models including aspects of Recentfeeding, research advances beenas primarily between empirical and modelling studies. Empirical studies have larval growth and have mortality, well asdivided behaviour. There is a need in the future to use empirical studies to included measurement of dispersal stable isotope marking, DNA tools parentage analysis microchemistry. validate biophysical models so that using they can then be used as reliable to study spatialand andotolith temporal variation in Modelling connectivity studies haveand seen the development of increasingly sophisticated biophysical models including aspects of dispersal, recruitment. larval feeding, growth and mortality, as well as behaviour. There is a need in the future to use empirical studies to validate biophysical models so that they can then be used as reliable tools to study spatial and temporal variation in dispersal, connectivity and recruitment.



Dr Alison King Charles Darwin University, Northern Territory, Australia KEYNOTE BIOGRAPHY AND ABSTRACT

Dr Alison King Charles Darwin University, Northern Territory, Australia

Alison is a Principal Research Fellow at Charles Darwin University, Northern Territory and has over 15 years experience researching the ecology of river systems, with a focus on the ecology of freshwater fish. A major research theme has been the spawning and recruitment ecology of freshwater fish, particularly in the Murray-Darling Basin. She currently leads a team broadly investigating the role of flow in the ecology of fish, with their research primarily targeted at developing applied science outcomes to underpin river restoration and management, particularly environmental flows. Alison is a Principal Research Fellow at Charles Darwin University, Northern Territory and has over 15 years experience She is regularly involved with expert panels and management committee’s, and often provides advice to managers and researching the ecology of river systems, with a focus on the ecology of freshwater fish. A major research theme has policy officers. She has published over 30 journal articles and book chapters, and numerous reports and conference been the spawning and recruitment ecology of freshwater fish, particularly in the Murray-Darling Basin. She currently presentations. leads a team broadly investigating the role of flow in the ecology of fish, with their research primarily targeted at developing applied science outcomes to underpin river restoration and management, particularly environmental flows. She is regularly involved with expert panels and management committee’s, and often provides advice to managers and policy officers. She has published over 30 journal articles and book chapters, and numerous reports and conference presentations. Not just “Goin’-with-the-Flow”: challenges in understanding the movement patterns of the early life stages of Australian freshwater fish Alison King Research Institute for the Environment and Livelihoods, Charles Darwin University, Darwin, NT 0909, Australia. Email: [email protected] Not just “Goin’-with-the-Flow”: challenges in understanding the movement patterns of the early life stages of 1 NT Fisheries, Department of Resources – Fisheries, GPO BOX 3000, Darwin NT 0801. Australian freshwater fish Alison King Freshwater fish need to be able to successfully reproduce and recruit in a wide variety of habitat and flow conditions – Research Institute for the Environment and Livelihoods, Charles Darwin University, Darwin, NT 0909, Australia. often in extremely challenging environments, such as floods and droughts. Understanding the movement or dispersal of Email: [email protected] eggs, larvae and juveniles of freshwater fish in these environments poses unique challenges. In particular, these early 1 NT Fisheries, Department of Resources – Fisheries, GPO BOX 3000, Darwin NT 0801. life stages are too small for traditional tagging approaches, so a range of methodologies (for example active and passive collection gears, otolith chemistry and experiments), have been employed to mostly infer and provide insight into the Freshwater fish need to be able to successfully reproduce and recruit in a wide variety of habitat and flow conditions – movements of young fish. often in extremely challenging environments, such as floods and droughts. Understanding the movement or dispersal of The swimming abilities of larvae vary greatly, and typically improve with increased body size and ontogeny, but most can eggs, larvae and juveniles of freshwater fish in these environments poses unique challenges. In particular, these early undertake large-scale movements only with the assistance of a current. In some species, the adults are thought to life stages are too small for traditional tagging approaches, so a range of methodologies (for example active and passive spawn upstream and rely on the flow of rivers to disperse the young downstream. However, far from being passively collection gears, otolith chemistry and experiments), have been employed to mostly infer and provide insight into the entrained by the current with no control over their destination, we know that late-stage larvae of some species (for movements of young fish. example Murray cod) seem to be able to regulate when, where and for how long they drift. Other species undertake little The swimming abilities of larvae vary greatly, and typically improve with increased body size and ontogeny, but most can movement as eggs and larvae, and seem to disperse as juveniles and/or adults. This diversity of movement patterns by undertake large-scale movements only with the assistance of a current. In some species, the adults are thought to young freshwater fish and the range of environments they use, pose significant challenges both to the individual fish – spawn upstream and rely on the flow of rivers to disperse the young downstream. However, far from being passively and the individuals trying to study them! This presentation will discuss the challenges in studying the movements of entrained by the current with no control over their destination, we know that late-stage larvae of some species (for young freshwater fish and present case studies of the approaches that have proven successful. example Murray cod) seem to be able to regulate when, where and for how long they drift. Other species undertake little movement as eggs and larvae, and seem to disperse as juveniles and/or adults. This diversity of movement patterns by young freshwater fish and the range of environments they use, pose significant challenges both to the individual fish – and the individuals trying to study them! This presentation will discuss the challenges in studying the movements of young freshwater fish and present case studies of the approaches that have proven successful.



Dr Jayson Semmens Institute of Marine and Antarctic Studies, Tasmania, Australia KEYNOTE BIOGRAPHY AND ABSTRACT

Dr Jayson Semmens Institute of Marine and Antarctic Studies, Tasmania, Australia

After receiving his PhD from JCU in 2000, Jayson began an ARC Postdoc at UTAS in 2001 and has been there ever since. A major focus of his UTAS research has been examining the movement, migration and activity of marine animals, with the aim of understanding the underlying biological and ecological drivers behind these behaviours. Jayson has employed acoustic tracking, telemetry and biologging approaches for a wide variety of marine organisms, including crustaceans, fish, cephalopods, sharks and seals, often with the aim of developing spatial management strategies. More After receiving PhD fromphysiological JCU in 2000,telemetry Jayson began an ARC at UTAS in 2001 rate and of hasmarine been animals there ever recently he hashis established approaches forPostdoc estimating the metabolic in since. A major focus of research been examining the movement, and activity marineinfluence animals, the field. This allows forhis theUTAS energetic costshas associated with different activities tomigration be estimated and theofrelative withthe the of understanding the underlying and ecological behind these behaviours. Jayson how has on lifeaim history strategies determined. Jaysonbiological has also begun to use thisdrivers field metabolic data to better understand employed tracking, telemetry changes and biologging approaches animals areacoustic coping with anthropogenic in marine systems. for a wide variety of marine organisms, including crustaceans, fish, cephalopods, sharks and seals, often with the aim of developing spatial management strategies. More recently he has established physiological telemetry approaches for estimating the metabolic rate of marine animals in the field. This allows for the energetic costs associated with different activities to be estimated and the relative influence on the life history strategies determined. Jayson has also begun to use this field metabolic data to better understand how animals are coping changes in marine systems. Where, when, howwith andanthropogenic why: Using acoustic telemetry to understand marine animal movement, behaviour and physiology. Jayson Semmens Fisheries, Aquaculture and Coasts Centre, Institute for Marine and Antarctic Studies, University of Tasmania, Hobart, Tasmania, Australia. [email protected] Where, when, how and why: Using acoustic telemetry to understand marine animal movement, behaviour and physiology. Since the late 1950s marine scientists have utilised acoustic telemetry to examine and understand the movement, Jayson Semmens behaviour and physiology of marine animals in the world’s oceans and estuaries. This work gathered momentum in the Fisheries, and Coasts and Centre, Institute for Marine AntarctictoStudies, University late 1990sAquaculture as the microcomputer digital revolution spreadand technology the masses. NowofinTasmania, 2012, the Hobart, use of Tasmania, Australia. acoustic telemetry is [email protected] changing our understanding of a wide variety of marine animals and how they interact with their environment, but also helping managers to ensure the sustainability of commercially targeted or conservation dependant Since theHere late I1950s marine scientists utilisedstatus acoustic telemetrytelemetry to examine understand thefuture movement, species. provide an overview of have the current of acoustic and and a direction for the using behaviour from and physiology of marine in my the research world’s oceans and examining estuaries. the Thismovement, work gathered in the examples my research. A majoranimals focus of has been and momentum activity of marine late 1990s asthe theaim microcomputer and the digital revolution spread and technology to drivers the masses. 2012, the use of animals, with of understanding underlying biological ecological behindNow theseinbehaviours. I have acoustic telemetry changing our understanding a wide variety marine organisms, animals andincluding how theycrustaceans, interact with their employed acousticis telemetry approaches for a ofwide variety of ofmarine fish, environment, but helping managers to ensure sustainability of commercially or conservation dependant cephalopods andalso sharks, often with the aim of the developing spatial managementtargeted strategies. More recently I have species. Here I provide an overview of the current status of the acoustic telemetry a direction using established physiological telemetry approaches for estimating metabolic rate ofand marine animalsforin the the future field. These examples from myfor research. A major focus of my research has been examining the movement, activity of marine approaches allow the energetic costs associated with different activities to be estimated and theand relative influence on animals, with the aim of understanding the underlying biological andisecological drivers behind these behaviours. I have the life history strategies to be determined. Physiological telemetry likely to be an area of acoustic telemetry that will employed acoustic a wideforvariety of marine crustaceans, fish, rapidly expand in thetelemetry future, asapproaches it has greatfor potential understanding howorganisms, animals areincluding coping with anthropogenic cephalopods and systems. sharks, often with the aim of developing spatial management strategies. More recently I have changes in marine established physiological telemetry approaches for estimating the metabolic rate of marine animals in the field. These approaches allow for the energetic costs associated with different activities to be estimated and the relative influence on the life history strategies to be determined. Physiological telemetry is likely to be an area of acoustic telemetry that will rapidly expand in the future, as it has great potential for understanding how animals are coping with anthropogenic changes in marine systems.



Dr John Koehn Arthur Rylah Institute for Environmental Research, Victoria, Australia KEYNOTE BIOGRAPHY AND ABSTRACT

Dr John Koehn Arthur Rylah Institute for Environmental Research, Victoria, Australia

John is a fish biologist with 30 years experience in research, assessment, conservation and management of Australian native freshwater fishes. He is the author of over 180 scientific publications, 44 of which have involved fish tagging, tracking or fish movements in some form. He has published widely on threats to native species, including ensuring river connectivity and the provision of fish passage. Forthcoming publications include a chapter in an American Fisheries Society Biotelemetry book and a chapter on Fish movements and migration in the Ecology of Australian Freshwater Fishes. Since tagging his first river blackfish in 1983, he has pioneered larval collection of Murray Darling Basin species John is aradio fish biologist 30 years experience research, conservation and including management of Australian and the tracking with of Australian freshwater in fish, trackingassessment, many of our iconic species Murray cod. He native freshwater fishes. He is the author of over 180 scientific publications, 44 of which have involved fishMigration, tagging, organised and co-edited the Australian Society for Fish Biology 1999 Bendigo Workshop Fish Movement and tracking fish movements in some form. He has published widelyison to nativeofspecies, including ensuring and the or climate change symposium in Melbourne in 2010. John a threats past President the Australian Society for river Fish connectivity and the provision of fish passage. Forthcoming publications include a chapter in an American Fisheries Biology. Society Biotelemetry book and a chapter on Fish movements and migration in the Ecology of Australian Freshwater Fishes. Since tagging his first river blackfish in 1983, he has pioneered larval collection of Murray Darling Basin species and the radio tracking of Australian freshwater fish, tracking many of our iconic species including Murray cod. He organised and co-edited the Australian Society for Fish Biology 1999 Bendigo Workshop Fish Movement and Migration, and the climate change Tagging freshwater fishsymposium in Melbourne in 2010. John is a past President of the Australian Society for Fish Biology. John Koehn, Jarod Lyon, Wayne Koster, Matthew Jones Arthur Rylah Institute for Environmental Research, Heidelberg [email protected]

Tagging freshwater This paper will reviewfish and assess the current status of tagging techniques for freshwater fish, discuss the advantages John Koehn, Jarod of Lyon, Wayne Koster, Matthew and disadvantages each, and consider what to Jones use when. Consideration will also be given as to why any of these Arthur Rylahshould Institute Environmental Research, techniques be for used at all (depending on theHeidelberg questions being asked), and how they can be integrated with other [email protected] methods to provide maximum additional knowledge to the ‘biological picture’. Focus will be given to the latest tagging

techniques, particularly in relation to understanding fish movements. This includes discussion of radio and acoustic telemetry and PIT (Passive Integrated Transponder) tagging, with case studies demonstrating the utility of each. Radio This paper will review and the current offish tagging techniques for freshwater fish, discuss the the advantages and acoustic telemetry haveassess been widely used status to study movements. Radio-tags were first used to study habitats and disadvantages of each, and whatinto1992 use and when. Consideration will alsotobe given as to why any these and movements of freshwater fishconsider in Australia have since been applied study a broad range of of species. techniques should be used at all (depending on the questions being asked), and how they can be integrated with Technological developments have recently made acoustic tagging more applicable to freshwater studies where itother now methods to provide has increasing use. maximum additional knowledge to the ‘biological picture’. Focus will be given to the latest tagging techniques, particularly relation to understanding fish movements. This includes discussion of radio andusing acoustic Case study 1: Spawninginand movement patterns of Australian grayling were investigated in the Bunyip River drift telemetry and acoustic PIT (Passive Integrated Transponder) tagging, case studies demonstrating the utility of each. Radio sampling and telemetry. Specifically, this study was with to determine whether adult Australian grayling undertook and acoustic migrations telemetry have been widely used of to rivers study fish movements. Radio-tags used2:toRadio-tags study the habitats downstream to the lower reaches during the spawning period.were Casefirst study and an and of freshwater in Australia in 1992 and have since been applied to study a broad range of species. arraymovements of fixed logging stations fish are being used on the Murray River to measure fish population changes in response to Technological developments have recently made tagging more applicable to the freshwater studiesmortality where itrates, now habitat rehabilitation. This has provided data on acoustic immigration and emigration to/from study zones, has and increasing estimates use. of electrofishing detection rates to inform a catch model. Case study 3: PIT (Passive Integrated Case study 1: tags Spawning and movement of aAustralian grayling werefish investigated in the Bunyip drift Transponder) are increasingly beingpatterns used as lower cost individual tagging option. Over 20River 000 using fish have sampling and acoustic Specifically, Basin this study was to determine whether adult Australian grayling undertook been PIT tagged as parttelemetry. of the Murray-Darling Commission’s Sea to Hume Dam fishway program. Automated PIT downstream migrations the reaches rivers during theproviding spawningcoverage period. Case study 2: river Radio-tags readers are now installedtoon 12lower fishways alongofthe Murray River, of over 1 730 km andand overan 2 array‘recaptures’ of fixed logging stations being used on the Murray River to measure fish population changes in response to 700 have now beenare recorded. habitat rehabilitation. This has provided data on immigration and emigration to/from the study zones, mortality rates, and estimates of electrofishing detection rates to inform a catch model. Case study 3: PIT (Passive Integrated Transponder) tags are increasingly being used as a lower cost individual fish tagging option. Over 20 000 fish have been PIT tagged as part of the Murray-Darling Basin Commission’s Sea to Hume Dam fishway program. Automated PIT readers are now installed on 12 fishways along the Murray River, providing coverage of over 1 730 river km and over 2 700 ‘recaptures’ have now been recorded.



Dr Jenny Ovenden Molecular Laboratory, KEYNOTEFisheries BIOGRAPHY AND Queensland ABSTRACTDepartment of Employment, Economic Development and Innnovation, Brisbane, Queensland, Australia Dr Jenny Ovenden Molecular Fisheries Laboratory, Queensland Department of Employment, Economic Development and Innnovation, Brisbane, Queensland, Australia

Jenny Ovenden is a principal research scientist with the Queensland Government and an adjunct associate professor at the University of Queensland. With her team at the Molecular Fisheries Laboratory http://www.dpi.qld.gov.au/4791_6844.htm, Jenny uses population and molecular genetics as well as maths and stats for research on commercial fisheries species in Australia. The team collaborates with researchers in agencies around Australia and worldwide. The work covers many species from sharks and rays, through finfish to invertebrates such as Jenny Ovenden is a principal research scientist with the Queensland Government and an adjunct associate professor at crustaceans and molluscs. Jenny is an associate editor of Marine and Freshwater Research, Fish and Fisheries and the University of Queensland. With her team at the Molecular Fisheries Laboratory Integrative Zoology, a committee member of SeaWorld Research and Rescue Foundation and a member of the IUCN http://www.dpi.qld.gov.au/4791_6844.htm, Jenny uses population and molecular genetics as well as maths and stats for shark specialist group. research on commercial fisheries species in Australia. The team collaborates with researchers in agencies around Australia and worldwide. The work covers many species from sharks and rays, through finfish to invertebrates such as crustaceans and molluscs. Jenny is an associate editor of Marine and Freshwater Research, Fish and Fisheries and Integrative Zoology, a committee member of SeaWorld Research and Rescue Foundation and a member of the IUCN shark specialist group. Crinkles in connectivity: a genetic perspective on the influence of movement on fisheries stock structure Jennifer R. Ovenden Molecular Fisheries Laboratory, Queensland Government, Brisbane, Queensland, Australia. http://www.dpi.qld.gov.au/4791_6844.htm [email protected] Crinkles in connectivity: a genetic perspective on the influence of movement on fisheries stock structure Jennifer R. Ovenden Most marine species occur in extensive, continuous habitat, yet generally can be broken up into separate stocks based Molecular Fisheries Laboratory, Queensland Government, Brisbane, Queensland, Australia. on genetic (or other, eg. parasites or otoliths) characteristics. Movement between stocks is the glue that holds separate http://www.dpi.qld.gov.au/4791_6844.htm [email protected] stocks together into a single species. Genetically distinct stocks exist due to crinkles in connectivity (where stocks do not exchange enough migrants to maintain similarity) or phylogeography (where a single population is cleaved into two by an impermeable barrier). The deep water of the Timor Trench is a local phylogeographic barrier, separating stocks of Most marine species occur in extensive, continuous habitat, yet generally can be broken up into separate stocks based some snapper, mackerel and shark species. In future, this barrier may filter the southward movement of south-east on genetic (or other, eg. parasites or otoliths) characteristics. Movement between stocks is the glue that holds separate Asian species into the waters of northern Australia in response to predicted changes in water temperature. Even when stocks together into a single species. Genetically distinct stocks exist due to crinkles in connectivity (where stocks do not there is no barrier between stocks, connectivity between stocks is not assured. Migrants are animals that leave their exchange enough migrants to maintain similarity) or phylogeography (where a single population is cleaved into two by natal stock and take up residence in another stock. If enough migrants are exchanged, then stocks become genetically an impermeable barrier). The deep water of the Timor Trench is a local phylogeographic barrier, separating stocks of and demographically identical. As the number of migrants hypothetically decreases, others have noted that demographic some snapper, mackerel and shark species. In future, this barrier may filter the southward movement of south-east ties between the stocks are broken before genetic ties. This is explained because demographic ties depend on the ratio Asian species into the waters of northern Australia in response to predicted changes in water temperature. Even when between migrant numbers and local population size, but genetic ties depend on the absolute number of migrants. Here I there is no barrier between stocks, connectivity between stocks is not assured. Migrants are animals that leave their highlight categories of migrants that tie stocks together; those that become resident and those that become resident and natal stock and take up residence in another stock. If enough migrants are exchanged, then stocks become genetically join the local breeding population, and discuss how the migrant’s life-history stage influences migrant category. For and demographically identical. As the number of migrants hypothetically decreases, others have noted that demographic example, if larvae are most commonly exchanged between stocks, they may be less likely to become residents because ties between the stocks are broken before genetic ties. This is explained because demographic ties depend on the ratio of high mortality to the adult stage. But, if they do survive to adulthood they have a high chance of participating in between migrant numbers and local population size, but genetic ties depend on the absolute number of migrants. Here I spawning. Understanding the effect of life-history stage on movement between stocks and the mismatch between highlight categories of migrants that tie stocks together; those that become resident and those that become resident and genetic and demographic connectivity may allow fine-tuning of mathematical models of fish populations for setting and join the local breeding population, and discuss how the migrant’s life-history stage influences migrant category. For monitoring limits to harvesting. example, if larvae are most commonly exchanged between stocks, they may be less likely to become residents because of high mortality to the adult stage. But, if they do survive to adulthood they have a high chance of participating in spawning. Understanding the effect of life-history stage on movement between stocks and the mismatch between genetic and demographic connectivity may allow fine-tuning of mathematical models of fish populations for setting and monitoring limits to harvesting.



KEYNOTE BIOGRAPHY AND ABSTRACT Dr Craig Mundy Institute of Marine and Antarctic Studies, Tasmania, Australia Dr Craig Mundy Institute of Marine and Antarctic Studies, Tasmania, Australia

Dr Craig Mundy has been the Abalone Biologist at the Institute for Marine and Antarctic Studies (formerly Tasmanian Aquaculture and Fisheries Institute), University of Tasmania for the last 10 years and is primarily responsible for abalone wild fisheries research within Tasmania (the world's largest wild abalone fishery). He has had 26 years’ experience with sub-tidal biology has and been ecology tropical to temperate worked and studied at theTasmanian Australian Dr Craig Mundy the ranging Abalonefrom Biologist at the Institute forwaters. MarineCraig and Antarctic Studies (formerly Institute of Marine Science for 10 University years focusing on community and reproductive biology of Aquaculture and Fisheries Institute), of Tasmania for the lastdynamics 10 years of andcorals is primarily responsible for abalone echinoderms, and survey andTasmania experimental to Newfishery). Zealand. PhD role of larval wild fisheries research within (the design world'sbefore largestshifting wild abalone HeHis has hadexamined 26 years’ the experience with behaviour in recruitment process and dynamics of scleractinian corals. Craig’s current research interests in sub-tidal biology and ecology ranging from tropical to temperate waters. Craig worked and studied at are the focused Australian two distinct the ecology of exploited abaloneonpopulations, importance of early life history Institute of areas Marine1)Science for 10 years focusing community specifically dynamics the of corals and reproductive biologyand of reproductive in managing exploitation of blacklip and greenlip abalone; and the examined use of digital methods for echinoderms,ecology and survey and experimental design before shifting to New Zealand. His2)PhD the role of larval collecting geo-referenced fisheries and of thescleractinian applicationcorals. of spatial statistical methodsinterests for informing fishery behaviour in recruitment process and data dynamics Craig’s current research are focused in assessment in small fisheries. two distinct areas 1) vessel the ecology of exploited abalone populations, specifically the importance of early life history and reproductive ecology in managing exploitation of blacklip and greenlip abalone; and 2) the use of digital methods for collecting geo-referenced fisheries data and the application of spatial statistical methods for informing fishery assessment in small vessel fisheries. Application of animal movement analytical techniques to fishery data: how do you turn a dataset with 25,000 dives and 10,000,000 records per year into meaningful information? Craig Mundy Institute for Marine and Antarctic Studies Application of animal movement analytical techniques to fishery data: how do you turn a dataset with 25,000 University Tasmania,records Hobart per year into meaningful information? dives and of 10,000,000 [email protected] Craig Mundy Institute for Marine and Antarctic Studies Australian Abalone Fisheries University of Tasmania, Hobarttypically target spatially structured stocks, often in remote areas. The nature of these fishing operations means precise recording of fishery-dependent data is challenging, and fishery independent data [email protected] collection to determine stock status is cost prohibitive. An electronic data collection system has been developed at the University Tasmania, using typically passive GPS depth/time data loggers collect high-resolution, high-quality Australian of Abalone Fisheries targetand spatially structured stocks, to often in remote areas. The nature ofspatial these location and effort means data from abalone divers. ofThe geo-referenced data diver is data are used to calculate range of spatial fishing operations precise recording fishery-dependent challenging, and fishery aindependent data performance measures stock for assessing the performance the fishery at collection an appropriate scale. Central to collection to determine status is cost prohibitive. Anofelectronic data systemspatial has been developed at the development these spatial measures are analytical methodstowidely in animal movement research – University of of Tasmania, usingperformance passive GPS and depth/time data loggers collectused high-resolution, high-quality spatial kernel density functions and abalone path classification – geo-referenced to determine home andused animal movement behaviour. The location and effort data from divers. The diver range data are to calculate a range of spatial application of measures these approaches to analysis of fishery dataofusing the R statistical package will be illustrated in relation to performance for assessing the performance the fishery at an appropriate spatial scale. Central to the these two common animal behaviour questions. development of these spatial performance measures are analytical methods widely used in animal movement research – kernel density functions and path classification – to determine home range and animal movement behaviour. The application of these approaches to analysis of fishery data using the R statistical package will be illustrated in relation to these two common animal behaviour questions.



Dr Colin Simpfendorfer James Cook University, Queensland, Australia KEYNOTE BIOGRAPHY AND ABSTRACT

Dr Colin Simpfendorfer James Cook University, Queensland, Australia

Colin Simpfendorfer has spent most of his career researching the biology and ecology of sharks, with the aim of improving conservation and management of this iconic group. He received his PhD in Zoology from James Cook University in 1993 working on the life history of tropical sharks. He then worked on temperate shark fisheries at the Western Australian Fisheries Department. In 1998 he moved to Mote Marine Laboratory in Sarasota, Florida, where he eventually became the Manager of the Elasmobranch Fisheries and Conservation Program in the Center for Shark Colin Simpfendorfer hasresearch spent most of his career researching the biology and ecology of but sharks, with the aim an of Research. In Florida his focused on the conservation biology of endangered sawfish, he also developed improving and management of this iconic group. PhD in fromDirector James of Cook interest in conservation the analysis of data from acoustic monitoring studies.He In received 2007 he his returned to Zoology JCU as the the University in Fisheries 1993 working on theCentre. life history of tropical sharks. He thenappointments, worked on temperate fisheries at the Fishing and Research He holds several extra-mural includingshark Regional Vice-Chair Western Fisheries Department. 1998 he to Mote Marine Laboratory in Assessment Sarasota, Florida, he (Oceania)Australian for the IUCN’s Shark SpecialistInGroup, themoved Chair of AFMA’s Shark Resources Groupwhere and the eventually became the Animal ManagerTracking of the Elasmobranch Program in more the Center for journal Shark Chair of the Australian and MonitoringFisheries System’sand DataConservation Subcommittee. He has than 80 Research. Florida his including research focused on the conservation biology fisheries, of endangered sawfish, but he alsodata developed an publicationsIn on topics life history, population dynamics, conservation, ecology, analysis, interest themore. analysis of data from acoustic monitoring studies. In 2007 he returned to JCU as the Director of the parasitesinand Fishing and Fisheries Research Centre. He holds several extra-mural appointments, including Regional Vice-Chair (Oceania) for the IUCN’s Shark Specialist Group, the Chair of AFMA’s Shark Resources Assessment Group and the Chair of the Australian Animal Tracking and Monitoring System’s Data Subcommittee. He has more than 80 journal publications on topics including life history, population dynamics, fisheries, conservation, ecology, data analysis, parasites and“shiny more. new hammer”: data analysis tools to make the most of acoustic monitoring studies Beyond the Colin A. Simpfendorfer1, Michelle R. Heupel2,1 1 Centre for Sustainable Tropical Fisheries and Aquaculture & School of Earth and Environmental Sciences, James Cook University, Townsville, Queensland, Australia. [email protected] 2 Australian Institute of Marine Science, Townsville, Queensland, Australia Beyond the “shiny new hammer”: data analysis tools to make the most of acoustic monitoring studies 1 2,1 Colin A. of Simpfendorfer , Michelle Heupel The use acoustic monitoring as aR. tool in aquatic sciences has increased dramatically in the past two decades. Despite 1 Centre Sustainable Tropical Fisheries and Aquaculture & Schoolofofanalytical Earth andtools. Environmental Cook this, thefor outputs from this research are limited by the availability The data Sciences, produced James by acoustic University, Townsville, Queensland, Australia. [email protected] monitoring is very simple and as such requires extensive manipulation and processing during analysis. Once processed, 2 Australian Institute of Marine Science, Townsville, Australia data can yield a wide array of information about Queensland, animal location, movement, residency, fate and more. The use of extensive arrays of acoustic receivers can yield estimates of activity space and home range. Here we will compare The use of acoustic monitoring as a toolofin2-dimensional aquatic sciences has increased the past two decades. Despite different approaches to the estimation kernels, as well asdramatically demonstrateinhow 2-dimensional kernels can this, the outputs from this research are limited by the availability of analytical tools. The data produced by acoustic be extended to 3-dimensions to improve our understanding of space use. Approaches to examining the residency of monitoring is very simplemonitoring and as such manipulation processing analysis. processed, animals using acoustic at requires a varietyextensive of time scales will be and described in theduring context of the Once evaluation of the data canofyield a wide arrayareas. of information animal location, fate and more.drivers The use of efficacy marine protected The use ofabout acoustic monitoring to movement, examine theresidency, effects of environmental on the extensive of acoustic receivers can yield estimates of activity space and home range. the Herepower we will movementarrays of animals will also be examined using data from a riverine habitat. To harness of compare acoustic different approaches the estimation of 2-dimensional kernels, as well as the demonstrate how 2-dimensional kernels can monitoring data userstoneed to understand how the equipment works, what data represent and be innovative in their be extended to 3-dimensions to improve our understanding of space use. Approaches to examining the residency of approaches. animals using acoustic monitoring at a variety of time scales will be described in the context of the evaluation of the efficacy of marine protected areas. The use of acoustic monitoring to examine the effects of environmental drivers on the movement of animals will also be examined using data from a riverine habitat. To harness the power of acoustic monitoring data users need to understand how the equipment works, what the data represent and be innovative in their approaches.



Dr Simon Goldsworthy South Australian Research and Development Institute, Adelaide, South Australia, Australia KEYNOTE BIOGRAPHY AND ABSTRACT

Dr Simon Goldsworthy South Australian Research and Development Institute, Adelaide, South Australia, Australia

Simon Goldsworthy has been undertaking research in the field of marine biology for 25 years. His main research interests include the ecology of marine mammals and seabirds, ecosystem trophodynamics, and the mitigation of interactions between protected marine species and fisheries. He undertook his Bachelor of Science and PhD degrees at Monash University in Melbourne, completing the latter in 1992. He then undertook a two-year Post-doctoral Research Fellowship at the Smithsonian Institution in the USA. After returning to Australia in 1995, he worked for two years Simon Goldsworthy has been undertaking research in the field of marine biology for 25 years. His main research monitoring the impacts of Australia’s largest on-shore oil spill, the Iron Baron, on little penguin populations in Tasmania; interests include the ecology of marine mammals and seabirds, ecosystem trophodynamics, and the mitigation of then for 2 years at CSIRO Marine Research in Hobart, investigating the ecological effects of subantarctic fisheries for interactions between protected marine species and fisheries. He undertook his Bachelor of Science and PhD degrees at Patagonian toothfish around Macquarie Island. In 2000, he took up a lecturing position in the Zoology Department at La Monash University in Melbourne, completing the latter in 1992. He then undertook a two-year Post-doctoral Research Trobe University in Melbourne, and in 2004 he moved to South Australia to take up a position as Principal Scientist with Fellowship at the Smithsonian Institution in the USA. After returning to Australia in 1995, he worked for two years SARDI Aquatic Sciences where he heads the Threatened, Endangered and Protected Species Subprogram. He monitoring the impacts of Australia’s largest on-shore oil spill, the Iron Baron, on little penguin populations in Tasmania; currently coordinates a number of significant research programs that focus on the foraging and population ecology of then for 2 years at CSIRO Marine Research in Hobart, investigating the ecological effects of subantarctic fisheries for pelagic predators and ecosystem dynamics in the eastern Great Australian Bight. Patagonian toothfish around Macquarie Island. In 2000, he took up a lecturing position in the Zoology Department at La Trobe University in Melbourne, and in 2004 he moved to South Australia to take up a position as Principal Scientist with SARDI Aquatic Sciences where he heads the Threatened, Endangered and Protected Species Subprogram. He currently coordinates a number of significant research programs that focus on the foraging and population ecology of pelagic predators and ecosystem dynamics in the eastern Great Australian Bight. Impact and mitigation of Australian sea lion bycatch in the shark gillnet fishery off South Australia Simon Goldsworthy South Australian Research & Development Institute, Adelaide, South Australia [email protected] Impact andthe mitigation sea lion bycatch inspecies the shark gillnet fishery South Australia Assessing impacts of of Australian fishery bycatch on protected is challenging but off of critical importance with greater Simon Goldsworthy demands for sustainable fisheries and seafood products. Fishery observer data are typically used to assess bycatchSouth Australian & Development Institute,across Adelaide, Australia rates per unit ofResearch fishing effort, and extrapolated theSouth fishery. However, bycatch rates provide an imprecise [email protected] estimate of bycatch number as observer programs generally monitor a fraction of total fishing effort, are difficult to replicate and the underlying encounter probabilities (which determine bycatch rates) are often highly heterogeneous. Assessing the impacts of fishery bycatch on protected species is challenging but of critical importance with greater Australian sea lions (Neophoca cinerea) (ASL) are subject to incidental mortality (bycatch) in demersal gillnet shark demands for sustainable fisheries and seafood products. Fishery observer data are typically used to assess bycatchfisheries. Bycatch has been identified as the key threatening factor for the species, and recently fishery closures have rates per unit of fishing effort, and extrapolated across the fishery. However, bycatch rates provide an imprecise been introduced to mitigate bycatch impacts. To assess the risks to ASL subpopulations from bycatch mortality data estimate of bycatch number as observer programs generally monitor a fraction of total fishing effort, are difficult to from four main sources were integrated and modelled: i) satellite tracking data to estimate distribution of foraging effort ; replicate and the underlying encounter probabilities (which determine bycatch rates) are often highly heterogeneous. ii) survey data on ASL subpopulation size; iii) data from a dedicated ASL bycatch observer program and iv) detailed Australian sea lions (Neophoca cinerea) (ASL) are subject to incidental mortality (bycatch) in demersal gillnet shark spatial data on the distribution of fishing effort. Satellite telemetry data from 210 adult female, adult male and juvenile fisheries. Bycatch has been identified as the key threatening factor for the species, and recently fishery closures have ASL from 17 subpopulations, in conjunction with depth and distance from colony data, were used to develop statistical been introduced to mitigate bycatch impacts. To assess the risks to ASL subpopulations from bycatch mortality data models of the distribution of foraging effort across the population. Bycatch mortality rates based on observer data were from four main sources were integrated and modelled: i) satellite tracking data to estimate distribution of foraging effort ; highly correlated with ASL foraging density, enabling levels of bycatch mortality that would result from different ii) survey data on ASL subpopulation size; iii) data from a dedicated ASL bycatch observer program and iv) detailed distributions and levels of fishing effort to be estimated. This approach Was used to estimate the impacts the fishery has spatial data on the distribution of fishing effort. Satellite telemetry data from 210 adult female, adult male and juvenile had on populations of ASL, and model the likely reduction in bycatch risk associated with a range of spatial closures ASL from 17 subpopulations, in conjunction with depth and distance from colony data, were used to develop statistical based around core female foraging areas, depth and minimum distance from colonies. A range of management models of the distribution of foraging effort across the population. Bycatch mortality rates based on observer data were measures to mitigate bycatch have been introduced into the fishery since July 2010, and these will be discussed. highly correlated with ASL foraging density, enabling levels of bycatch mortality that would result from different distributions and levels of fishing effort to be estimated. This approach Was used to estimate the impacts the fishery has had on populations of ASL, and model the likely reduction in bycatch risk associated with a range of spatial closures based around core female foraging areas, depth and minimum distance from colonies. A range of management measures to mitigate bycatch have been introduced into the fishery since July 2010, and these will be discussed.


AWARD PRESENTATIONS 2011 K. Radway Allen Award Some reflections of a lifetime in fishery science Rod. C. Lenanton WA Fisheries and Marine Research Laboratories, Department of Fisheries, Government of Western Australia 39 Northside Drive, Hillarys WA 6020, [email protected] After almost 50 years of involvement in fish and fishery science, an invitation to reflect on events experienced over those years invariably invokes recollections of the early days, and how very different things are now. So looking back over those years, I would like to identify a few of the changes that may be of interest, and that may also provide some insight into some important areas of endeavour for fishery science during the coming years. I will begin with my involvement in one of the state’s earliest fisheries, and then highlight factors that have contributed to the very different fates of several other longstanding coastal fisheries. Some of these factors, together with a further series of events, have contributed to a fundamental shift away from participation in such fishers, to alternative fisheries that have shaped the present utilisation of the finfish resources of Western Australia. A review of the performance of these fisheries also reveals that good science may not necessarily guarantee good management outcomes. It suggests also, that the encouragement of greater community involvement in fisheries science can encourage community acceptance of fishery management initiatives, and the more timely implementation of essential management changes.

2011 Inaugural Early Career Excellence Award Larval swimming performance and impacts on dispersal Rebecca Fisher Sinclair Knight Merz and the University of Western Australia Oceans Institute, Perth, Australia. Larval dispersal is shaped by the interaction between oceanographic processes and larval behaviour. A decade of research on the swimming performance of larval coral reef fishes clearly demonstrates their potential to behaviourally influence dispersal trajectories, with substantial consequences for connectivity patterns. The extent to which horizontal swimming might modify dispersal trajectories is critically dependent on swimming speed. However, measuring swimming ability in fishes is not trivial. Methodological differences and bias in the measurement of swimming performance confuses the ecological interpretation of research findings, making it unclear exactly what speeds larvae may be using to alter dispersal trajectories. In addition, there is also considerable species and family level variation in terms of both the development of swimming abilities, as well as overall abilities at settlement. Finally, behavioral changes during development, such as actively swimming at night, will also affect the degree to which larval may influence their dispersal. In this talk I will review these three aspects of swimming in larval fishes, drawing on my own research as well as others in the field. I will finish with some final recommendations of how swimming behavior may be included in dispersal models and potential effects on dispersal patterns for larval coral reef fishes.

OCS-Passions of Paradise Student Research Grant Habitat Associations of Deepwater Chondrichthyan Life History Traits Cassie Rigby and Colin Simpfendorfer Centre for Sustainable Tropical Fisheries and Aquaculture & School of Earth and Environmental Sciences, James Cook University, Townsville, Queensland, Australia Email: [email protected], [email protected] Life history traits are important indicators of the productivity of a species, and its ability to tolerate fishing pressure. Using a variety of life history traits (maximum size, size at maturity, age at maturity, longevity, growth rate and size at birth) from a wide range of chondrichthyans we demonstrate that there are life history differences between shelf, oceanic and deepwater habitats. Deepwater species have lower growth rates, later age at maturity and higher longevity than both shelf and oceanic species. We also examined the patterns in deepwater species life history traits by depth (upper, mid and deep slope), region (North and South Atlantic, North and South Pacific) and latitudinal zone (Polar, Temperate and Tropical). South Pacific deepwater chondrichthyans have higher growth rates and lower longevity than those in the other regions and size at birth was largest in species inhabiting the Temperate zones and the South Pacific region. There was a trend for both male and female chondrichthyans of lower growth rate, later age at maturity and higher longevity with increasing depth. However this trend was not significant when phylogenetic relatedness and size were taken into account which suggests that differences in species composition and size among habitats can drive these trends and stresses the importance of accounting for these to clearly determine the influence of habitat on life history traits. These associations of life history traits with habitat will be discussed within the context of ecological theories and conservation strategies.


oral abstracts


Estimating cryptic mortality for NZ sea lions using crash tests and video: Australia-NZ liaisons Edward Abraham2, Robert Anderson3, Martin Cryer1, Rohan Currey1, Jeremy Lyle4 and Giulio Ponte3 1 Ministry for Primary Industries, Wellington, New Zealand. 2 Dragonfly Science, Wellington, New Zealand. 3 Centre for Automotive Safety Research, University of Adelaide, Adelaide, SA, Australia. 4 Institute for Marine & Antarctic Studies, University of Tasmania, Hobart, TAS, Australia The New Zealand (NZ) sea lion (Phocarctos hookeri) is NZ’s only endemic pinniped and is gazetted as a threatened species. Sea lions are sometimes caught and drowned in NZ’s sub-Antarctic trawl fisheries, including that for arrow squid (Nototodarus sloanii) around the Auckland Islands. Since 2005, most vessels in this fishery have used sea lion exclusion devices (SLEDs) and, as a result, the numbers of observed and estimated captures have declined. Although SLEDs have reduced the observed level of mortality, it is possible that sea lions may undergo fatal, unobserved interactions with SLEDs at depth. Necropsy studies suggest head trauma from impacts with the SLED grid would be the most likely source of such cryptic mortality. We employed a novel approach to assess this possibility. The probability of mild traumatic brain injury (MTBI, or concussion, likely to be fatal at depth) was estimated using Bayesian modelling that combined data from custom biomechanical crash trials using a NZ SLED grid, with video footage from the Australian small pelagic fishery where Australian fur seals (Arctocephalus pusillus doriferus) interact with seal exclusion devices. The modelling indicated roughly a 3% chance that a sea lion striking a SLED grid will experience MTBI. This increases to about 8% if multiple parameters are assumed to fall close to plausible upper bounds. These results indicate the risk of mortality for NZ sea lions interacting with SLED grids is probably low, although a number of important assumptions and uncertainties remain. Understanding the animal ethics application process: some hints for expediency Stephen Balcombe Australian Rivers Institute, Brisbane, QLD, Australia. Animal Ethics Applications are one of the many administrative tasks we have to negotiate as fisheries scientists. Delays in the process can be extremely frustrating and costly, particularly when they are due to minor problems such as miscommunication between the researcher and their ethics committee. In this talk I present some “sage” advice to help overcome such delays based upon experience both as a committee member and as a “sometimes” frustrated researcher. The focus of this presentation will be around the application itself, adhering to the Australian Code of practice (NHMRC) and some of the common areas of fisheries research that are often sticking-points for animal ethics committees. Some of these points include, anaesthesia, sampling regime and numbers collected, or retained, experimental set-ups and experimental design. Differences in fish assemblages associated with wrack on sandy beaches between storm and calm events in Southern Australia Ryan Baring1, Peter Fairweather1 and Rebecca Lester2 1 Flinders University, South Australia, e-mail; [email protected] 2 Deakin University, Victoria, Australia Attached macrophytes that are detached from the seafloor during storms or large swell events accumulate as dense wrack in the surf zone of sandy beaches, particularly after storm events. These wrack accumulations act as an interim habitat for many juvenile fish and their invertebrate prey. Previous research indicates that particular amounts and types of wrack attract larger abundances and more diverse assemblages of fish in the surf zone. The process of wrack supply to the surf zone of sandy beaches varies according to storm conditions and the type of wrack material that grows in different coastal bioregions. Juvenile fish assemblages associated with wrack accumulations may also vary accordingly. In order to establish a better understanding of wrack as an interim habitat for juvenile fish in the surf zone of sandy beaches, we conducted multiple surveys immediately after storm events and during calmer periods in three coastal bioregions in South Australia. Some complex patterns were identified which indicates that wrack supply to surf zones of sandy beaches is not always the same after large storm events. The juvenile fish assemblages associated with wrack accumulations also show complex patterns across multiple storm events. This study provides further evidence that wrack supply into the surf zone and its fish association is highly variable and difficult to predict. The impact of marine closed areas on fishing yield under a variety of management strategies and stock depletion levels Belinda Barnes1 and Harvinder Sidhu2 1 DAFF, Canberra ACT Australia ([email protected]) 2 UNSW, University College, Canberra ACT Australia Closing areas to fishing has been mooted as an approach to management that hedges against uncertainty. In ecological terms, the protection of areas allowing for habitat regeneration and stock protection have obvious benefits; however, the impact on fishing yield is less certain. In this paper we use a simple closed area model to establish the impact of closure on yield under a number of distinct management strategies that determine stock targets and fishing quotas, for both under- and overexploited stocks. Our purpose is to determine broad scale trends in the dynamics, and to this end we specifically examine the effect of stock mobility, growth rate and proportion of habitat closed on yield and stock level, under each strategy. Our results quantify the relative impact on yield of spillover (replenishment) from closed areas into regions open to fishing, and provide a means of measuring the impact of closures on stock recovery times. This is particularly relevant in cases of uncertainty, possible overexploitation and the desire for reliable yields. Further, we discuss how to interpret the results in a manner that informs optimal closure design for a required outcome, in particular, closure that optimises a quota yield during stock recovery. 29 ASFB & OCS 2012 Joint Conference & Symposium Sebel Playford Hotel, Adelaide, South Australia 15-18 July 2012

Interactive effects of environment and genetics on the otolith chemistry of a temperate estuary associated sciaenid, mulloway (Argyrosomus japonicus) Thomas C. Barnes1 and Bronwyn M. Gillanders Southern Seas Ecology Laboratories, School of Earth and Environmental Sciences, University of Adelaide, SA 5005, Australia 1 Correspondence: Tel.: +618 8313 7035; Fax: +61 88303 4364; Email: [email protected] Otolith chemistry is widely used in fisheries science, and while significant progress has been made on environmental factors influencing elemental uptake, few studies have examined how environmental factors and genetics may influence otolith chemistry. Previous research has highlighted a species specific response of otolith trace elemental incorporation due to environmental variables, but intra specific genetic differences may also significantly influence otolith chemistry. This study assessed the influence of salinity, temperature and genetic stock on the incorporation of three key elements (Sr, Ba and Mg) into the otoliths of two stocks of Argyrosomus japonicus fingerlings reared in captivity. Elemental analysis via laser ablation ICPMS found that stock had a significant interactive effect on otolith Sr:Ca (salinity ! temperature ! stock) and Ba:Ca (salinity ! stock). Stock did not affect Mg:Ca incorporation, but Mg:Ca showed a positive relationship with temperature. These findings highlight the necessity to test multiple environmental variables and the consideration of discrete genetic differences on trace elemental signatures when applying this technique to environmental reconstructions (especially on fish from different stocks). Indicator fatty acids in multiple shark tissues and blood serum resulting from different artificial pellet diets Crystal Beckmann1,2, Jim G. Mitchell1, Laurent Seuront1,2,3, David Stone1,2 and Charlie Huveneers1,2 1 School of Biological Sciences, Flinders University, GPO Box 2100, Adelaide, South Australia 5001 2 South Australia Research and Development Institute (SARDI), Aquatic Sciences Centre, PO Box 120, Henley Beach South Australia 5024, 3 Centre National de la Recherche Scientifique, Laboratoire d’Océanologie et de Géosciences, UMR LOG 8187, Université des Sciences et Technologies de Lille, Station Marine, 62930 Wimereux, France Fatty acid (FA) profile analysis is a tool for dietary investigation that complements traditional stomach contents analysis. The application of FA profiles for dietary studies requires an understanding of the degree to which dietary FAs are reflected in shark tissues. An 18-week controlled feeding experiment was undertaken using Port Jackson sharks (Heterodontus portusjacksoni) held in captivity. Sharks were fed exclusive diets of artificial pellets treated with poultry oil (PO) or fish oil (FO) and compared to control sharks collected from the same region. The FA profiles from liver, muscle and blood serum were analysed every six weeks. By week 6, FA profiles of muscle and liver tissues of sharks fed PO treated pellets were significantly different to control sharks. However, it took twice as long for the muscle and liver tissues of FO-fed sharks to become significantly different to control sharks. Significant differences were also revealed in blood serum FA profiles of control and fed sharks by week 12. The FA profiles of PO- and FO-fed sharks were significantly different in liver tissue earlier than in muscle tissue and blood serum (6 and 18 weeks, respectively). The effectiveness of liver FA profiles as an indicator of shark diet was as a result of the liver’s major role in fat storage. Shark muscle and blood serum FA profiles were also influenced by diet; however, changes overtime were inconsistent and varied depending on the degree of dietary change. This study demonstrates the need for appropriate sampling protocols to infer diet in sharks. Fish movement at the terminus of the Murray-Darling Basin: past, present and future fish passage at the Murray Barrages Christopher M. Bice, Brenton P. Zampatti and Paul R. Jennings Inland Waters and Catchment Ecology Program, SARDI Aquatic Sciences, Adelaide, South Australia [email protected] The Murray Barrages, at the terminus of the Murray-Darling Basin, separate the freshwater Lower Lakes from the Coorong Estuary and Southern Ocean, and represent a significant barrier to fish movement between these environments. In 2004/05, three experimental fishways were constructed on the barrages but targeted assessments of these fishways indicated their effectiveness was limited. An underlying paradigm in the construction of effective fishways is knowledge of the migratory fish community, their ecology and behaviour. Thus a project was undertaken from 2006 – 2012 with the aim of investigating spatio-temporal variation in the composition of fish assemblages attempting to migrate upstream at the Murray Barrages and the ecological response of fish assemblages to freshwater inflows, to inform future fishway construction/modification and operation of the Murray Barrages. Over the study period >3 million individual fish, from a diverse assemblage of >50 species were sampled attempting to pass through existing fishways or within the vicinity of the Murray Barrages. There was significant spatio-temporal variation in fish assemblage structure (i.e. species composition and abundance) related to freshwater inflows, salinity and connectivity. Importantly, small-bodied fish species and life-stages (95%) the migratory fish community. Subsequently, new fishways were constructed with the objective of facilitating the passage of small-bodied species, particularly juveniles of catadromous species, and these fishways are performing satisfactorily. This project highlights the importance of understanding the ecology and movement patterns of local migratory fish communities to inform fishway construction and operation of regulatory structures.


Do Stocking Practices Influence Rainbow Trout Growth in a New Zealand Lake? A Bioenergetic Assessment Jennifer M. Blair1, Brendan J. Hicks1, Rob Pitkethley2, Nick Ling1, Ilia Ostrovsky3 and David Rowe4 1 Center for Ecology and Biodiversity Research, University of Waikato, Hamilton, New Zealand ([email protected]; [email protected]; [email protected] ) 2 Eastern Region Fish and Game, Rotorua, New Zealand ([email protected]) 3 Israel Oceanographic & Limnological Research, Kinneret Limnological Laboratory, Migdal, Israel ([email protected]) 4 National Institute for Water and Atmospheric Research, Hamilton, New Zealand ([email protected]) Several important rainbow trout (Oncorhynchus mykiss) fisheries are sustained or supplemented in New Zealand lakes by stocking of hatchery-raised yearlings. However, factors affecting growth of stocked trout in these lakes have not been investigated. We assessed the influence of stocking rates, stocking timing, and prey abundance on growth and prey consumption of rainbow trout in Lake Rotoiti, New Zealand. Growth trajectories were calculated from hatchery-origin trout that were released in spring (September-October) and autumn (April-May) 1995–2009 and recaptured by anglers. Prey consumption by trout in different age classes and cohorts was estimated using the Wisconsin bioenergetics model. Common smelt (Retropinna retropinna) accounted for 85% of total prey consumed. Trout released in autumn were smaller initially, but grew at a faster rate and displayed higher growth efficiency than trout released in spring. The number of yearlings released in a cohort was negatively correlated with modelled individual prey consumption rate in the first year of lake residence, suggesting that stocking rates may have caused density-dependent effects on growth. Because there is little risk of predation or overwintering mortality of stocked trout in Lake Rotoiti, stocking smaller trout (~160 mm fork length) in autumn is likely to produce larger fish than stocking larger fish (~200 mm) in spring. Possible reasons for enhanced growth of autumn-released trout include higher prey abundance in autumn and lower food demand over winter. These results highlight the importance of assessing stocking strategies on a case-by-case basis. Monitoring the fish community of the Great Darling Anabranch in the 2010-11 flood Deborah Bogenhuber and Danielle Linklater Murray-Darling Freshwater Research Centre, Mildura, Victoria, Australia Email: [email protected] The fish community of the Great Darling Anabranch was surveyed four times during the 2010/11 flood, at the following stages of the hydrograph: rising limb, flood peak, falling limb, and when flow had ceased. Eighteen sites were surveyed, spread across the 460 km watercourse, upstream and downstream of potential barriers to flow and fish movement. These barriers are located at the top of the system (upstream), approximately half-way, and at the bottom of the system (downstream). The fish community was dominated by large-bodied fish, with small-bodied fish represented primarily from weir pool sites. The large-bodied fish community was numerically dominated by Golden perch (Macquaria ambigua), but by Carp (Cyprinus carpio) in biomass. Other large-bodied fish species recorded in high numbers were Spangled perch (Leiopotherapon unicolor) and Bony herring (Nematolosa erebi). Patterns of abundances for these four species are presented over the four survey periods and within the four reaches delineated by potential fish barriers. Patterns in Golden perch abundance over the four survey periods differed between reaches; these are further explored through presentation of size-class data. On movement of Western Australian sharks Matias Braccini, Rory McAuley and Michael Moran Western Australian Fisheries and Marine Research Laboratories, Hillarys, Western Australia, Australia [email protected] Animals move at different scales and how they move has fundamental implications for a range of life history aspects, from localized habitat use to gene flow and the temporal and spatial organization of populations. Hence, understanding movement patterns is essential for setting effective management and conservation measures. In this talk, we present information on the movement of iconic (white) and commercially important (dusky, sandbar, whiskery and gummy) sharks from Western Australian. We use conventional tag-recapture (17 years of tagging data) and acoustic monitoring (193 receivers deployed along the west and southwestern coasts of Western Australia) for understanding the movement patterns of these species at different temporal and spatial scales and for different life history stages. Further, we use novel acoustic-monitoring and satellite-communication technologies (20 receivers), which allow for real-time detection of acoustically-tagged white sharks, as a way of balancing beach protection and white shark conservation. In this talk, we summarize current findings and discuss alternative approaches for modeling movement rates, and, ultimately, incorporation shark movement into population dynamic models for improved fisheries management.


Tracking broad-scale movements of a top-order predator using coastal sensor arrays and satellite telemetry Russell Bradford and Barry Bruce Wealth from Oceans Flagship, CSIRO Marine & Atmospheric Research, Hobart, Tasmania, Australia. The ability to collect long-term data on the movements of marine fishes is crucial to understanding patterns of distribution, migration, population connectivity and the significance of different habitats occupied. Considerable recent advances have been made in this area with the application of electronic tags, including satellite-linked, archival and acoustic tags. However, data are often restricted to short temporal scales relative to the life-time of a species and in most cases do not achieve data sets that permit annual and interannual cycles to be followed. The latter are particularly important for understanding cues that drive these patterns and the likely implications of environmental change on movements which have become a much touted goal for many studies. The longevity of acoustic tags and the ability to surgically implant them, now provides opportunities to monitor tagged animals over periods of up to 5-10 years. However, tag deployments need to be matched with deployments of acoustic receivers over suitable spatial and temporal scales to achieve viable data. We have monitored the broad-scale movements of individual juvenile white sharks (Carcharodon carcharias) since 2008 in eastern Australia, using a combination of passive acoustic and satellite telemetry. Shark movements ranged from northern Tasmania to the Great Barrier Reef, in many cases following similar migration pathways and showing annual fidelity to a geographically discrete nursery area off central New South Wales. Long-term passive acoustic tag data offers the opportunity to monitor annual and ontogenetic changes in movement patterns and estimates of juvenile survival in this species. The role of spatial ecology in the conservation management of Macquarie perch in the ACT Ben Broadhurst1, Mark Lintermans1, Brendan Ebner2, Jason Thiem3, Katie Ryan1, Rhian Clear1 and Danny Wright1 1 Institute for Applied Ecology, University of Canberra, Bruce, ACT, Australia 2 Landscapes Joint Venture, CSIRO Ecosystem Sciences & Australian Centre for Tropical Freshwater Research, Atherton QLD 3 Present address: Fish Ecology and Conservation Physiology Laboratory, Department of Biology, Carleton University, Ottawa, Ontario, Canada Information on spatial ecology is integral to successful conservation management of threatened freshwater fish. Over the past decade, a number of studies have been undertaken in the Australian Capital Territory (ACT) to investigate the movement, activity and habitat use of a remnant population of endangered Macquarie perch Macquaria australasica. These studies have primarily used radio-telemetry, but have also included underwater observation (video & snorkelling), PIT telemetry and conventional survey work. These studies have provided valuable information which has been directly fed into management both for onground works and resource management policy. This paper will present the findings and challenges of some of the key pieces of work and how they have directly influenced conservation management of Macquarie perch in the ACT. The effects of shark cage diving on the localised and broad-scale movements of white sharks in Australian waters Barry Bruce and Russell Bradford Wealth from Oceans Flagship, CSIRO Marine & Atmospheric Research, Hobart, Tasmania, Australia. The attraction of sharks for the purpose of tourism viewing is a lucrative and popular industry that remains controversial in terms of its possible risks to target species or its impacts on local ecosystems. The long-term impacts of such activities on the behaviour and movement patterns of sharks have typically been difficult to establish as most studies investigate contemporary behaviour concurrent with existing operations and thus have no comparative base from which to establish effects. We examined the spatial and temporal patterns of residency and behaviour of white sharks at the Neptune Islands in South Australia over a 10-year period (2001 – 2011) via industry logbooks and data from acoustictagged sharks using receiver arrays deployed in the island system and throughout Australian waters. The period spanned a significant change in shark-cage diving effort where operator activity doubled after 2007. Data indicated a significant increase in the number of sharks sighted after 2007. Acoustic data confirmed that sharks were temporary visitors to the Neptunes Islands and that individuals undertake broad-scale movements across their Australian range. However, sharks have significant increased their periods of residency at the Neptunes and the time periods spent within the areas where shark cage diving occurs since 2007. Concurrent with these changes was a shift in diel behaviour with the presence of sharks at sites aligning with the overall daily timing of cage-dive operations. This shift in behaviour also propagated through days when no cage diving operations occurred, suggesting a conditioned/anticipatory response by sharks to cage-diving activities.


Protecting the Harlequin Fish (Othos dentex) within South Australia’s New System of Marine Protected Areas: Acoustic Tracking to Determine Site Fidelity and Movement Patterns Simon Bryars1,3, Paul Rogers2 and David Miller1 1 Department of Environment and Natural Resources, Keswick, SA, Australia 2 South Australian Research and Development Institute & Flinders University of South Australia, SA, Australia. 3 Current address: Verdun, SA, Australia, [email protected] An acoustic telemetry study aimed at tracking the movements of the harlequin fish (Othos dentex) was undertaken off Kangaroo Island, South Australia. Seven acoustic receivers were deployed in a near-linear array 400 m apart on the sandy seabed adjacent to a narrow strip of high profile coastal reef. Ten harlequin fish (330–620 mm total length; 0.5–3 kg weight) were captured within the middle part of the array, implanted with an acoustic transmitter, and then released at their point of capture. Presence-absence and depth data were then passively monitored by the receiver array over a 16month period. Results showed that the harlequin fish is a site-attached, diurnal predator, with a relatively small home range. These characteristics, which had not been demonstrated previously, make individuals of the species amenable to long-term day-time monitoring techniques and to protection from localised impacts inside relatively small marine protected areas. Nonetheless, despite their high site fidelity, five of the fish underwent a coordinated alongshore migration during which they moved rapidly >800 m to the eastern extreme of the array. Three of the fish then returned to their original home range in the middle part of the array, one fish disappeared from the array, and the other fish permanently relocated its home range by ~800 m to the eastern end of the array. While it is most likely that the migration was related to an unusual storm event, such movements have implications for the size requirements of marine protected areas. The Devil is in the Detail: Tracking Movements in the Southern Blue Devil (Paraplesiops meleagris) using PhotoID Simon Bryars1,2 1 Department of Environment and Natural Resources, Keswick, SA, Australia 2 Current address: Verdun, SA, Australia, [email protected] The southern blue devil (Paraplesiops meleagris) is a small coastal reef fish endemic to southern Australia. The blue devil has numerous iridescent blue marks covering its body that offer potential for photographic identification (photo-ID) of individual fish. Using these markings it may be possible to develop a non-destructive/non-invasive photo-ID capturemark-recapture technique to monitor population demographics and site fidelity. A study was undertaken off Adelaide, South Australia, aimed at (1) assessing the potential of natural markings for photo-ID, (2) utilising photo-ID to make population estimates, and (3) utilising photo-ID to investigate site fidelity. Analysis of photos from a range of sources (including community divers) confirmed that the markings on adult blue devils are unique to individual fish and that they are temporally stable across many years. Population estimates were generated for four discrete reef systems: Seacliff Reef (n=40 fish), Northern Outer (n=9), Macs Ground (n=7), and Milkies (n=10). Traditional fish survey techniques would have greatly underestimated the population size of blue devils at Seacliff Reef; on average only ~50% of the total population was sighted on any given survey. Blue devils also showed a high degree of site fidelity at all reefs and their home range at Seacliff Reef was estimated to be relatively small at ~33 linear metres of reef. The photo-ID capturemark-recapture technique is now at a stage where it can enable long-term ongoing community monitoring of blue devils in the more accessible and popular dive sites around South Australia. Predicting Common Banana Prawn Potential Catch in Australia’s Northern Prawn Fishery Rik Buckworth1, Emma Lawrence2, Bill Venables2, Peter Rothlisberg1, Trevor Hutton1 and Fiona Hill3 1 CSIRO, Marine & Atmospheric Research, Brisbane, Qld, Australia 2 CSIRO, Mathematics, Informatics and Statistics, Brisbane, Qld, Australia 3 Australian Fisheries Management Authority, Canberra, ACT, Australia The Northern Prawn Fishery, like other Commonwealth-managed fisheries, is subject to a general policy of management by output controls. To determine appropriate Total Allowable Catch limits in this fishery, management requires a timely, reliable estimate of the potential catch of Common Banana Prawn, Penaeus merguiensis. Banana prawns are a resilient species that seem to recover quickly under current harvesting levels. To date, traditional stock-assessment methods have not been successful, possibly due to the animal’s unusual life cycle and resilience and so currently no stockassessment estimate of abundance is available. As the species appears to be strongly affected by environmental drivers, we investigated the use of rainfall data and the annual recruitment monitoring index to develop an empirical predictor for the potential catch. In this talk we will outline the robust statistical methods used to estimate the annual Common Banana Prawn potential catch at the Stock Region and overall fishery level. Finally we assess the reliability of the process using a retrospective analysis, together with other, more conventional uncertainty estimates. Using a Capture-Recapture Model to Estimate Natural Mortality of Lobsters in a Marine Reserve Paul Burch, Simon Wotherspoon and Stewart Frusher SARDI Aquatic Sciences, Henley Beach SA 5022 In fisheries stock assessment, natural mortality is one of the most difficult parameters to estimate. Biased estimates of natural mortality can result in fishing mortality being over or under estimated in stock assessment models. We developed a capture-recapture model to estimate natural mortality from daily tag resight data incorporating survey effort. We applied the model to tagging data from research trapping surveys undertaken in a marine reserve located at Crayfish Point, south of Hobart. Surveys were undertaken over a six year period from 1999 to 2005 with around 8000 lobsters were tagged inside the marine reserve. Estimates of natural mortality were determined to be high at around 39%, however, they were confounded with illegal fishing, tag loss and movement out of the reserve. 33 ASFB & OCS 2012 Joint Conference & Symposium Sebel Playford Hotel, Adelaide, South Australia 15-18 July 2012

Freshwater catfish (Tandanus tandanus) response to reconnection events of Washpen Creek, a large, midmurray paleochannel Lauren Carr1, Rick Stoffels2, Danielle Linklater1 and Rohan Rehwinkel3 1 Murray-Darling Freshwater Research Centre, Mildura, Victoria, Australia 2 CSIRO Land and Water, Wodonga, Victoria, Australia 3 NSW Department of Primary Industries, Narrandera, NSW, Australia One of the core tenets of the Flood Pulse Concept is that floods restore connectivity between a river and its floodplain, which in turn plays a key role in the life history of river-floodplain fishes. However, our understanding of lateral metapopulation processes in Australian river-floodplain fishes is extremely poor. Our objective was to determine how the freshwater catfish (Tandanus tandanus) of a large, mid-murray paleochannel (Washpen Creek) respond to two reconnection events, one artificial (regulator opening) and one natural (La Nina flood). While the natural reconnection event had a significant effect on the structure of the catfish population, no significant change in population structure was observed following the artificial reconnection event. The natural reconnection event resulted in increasing abundance of 0+ and sexually-mature adults, but a decrease in 2+ and 3+ individuals. Over four years of monitoring, mark-recapture analysis showed that growth of juveniles was extremely high in Washpen Creek, but adult growth was poor. We hypothesise that large floodplain wetlands may serve as productive spawning and nursery habitats for this species, and that relatively frequent (once every 3-5 years) may be beneficial for the mid-Murray population. Gut Histological Change of Yellowtail Kingfish Larvae during Weaning Ben Nan Chen1,2, Zhenhua Ma2, Wayne Hutchinson1, Jian G. Qin2, Jennifer Cobcroft3, Steven Battaglene3 and Mike S. Thomson4 1 South Australian Research and Development Institute, Adelaide, SA, Australia 2 School of Biological Sciences, Flinders University, Adelaide, SA, Australia 3 Institute for Marine and Antarctic Studies, Hobart, Tasmania, Australia 4 Clean Seas Tuna Ltd, Port Lincoln, SA, Australia Email: [email protected] Weaning is a critical step in the management of producing marine finfish fingerlings. In this study we determined the earliest age at which YTK larvae could feed inert microdiets measured by fish gut histology, survival, growth and jaw malformation. The experimental design included the same weaning regime commencing at five different days post hatching (DPH) namely 10 DPH (W10), 13 DPH (W13), 16 DPH (W16), 19 DPH (W19), and 22 DPH (W22) to identify the best weaning time. Fish survival and growth was significantly lower when an artificial diet was offered from either 10 DPH or 13 DPH as compared to those offered from 16 DPH, 19 DPH or 22 DPH. There was no significant difference in fish survival or growth when weaning stared at 16 DPH, 19 DPH or 22 DPH. The proportion of fish with jaw malformation at 33 DPH was not significantly affected by weaning age. Histological evidence showed that the mid-gut cell heights of larvae from W10 to W13 were significantly lower than in other treatments on 15 DPH. The gastric glands in the stomach occurred 15-18 DPH, which coincided with the high fish survival when artificial diets were offered to fish from 15DPH onwards. This study suggests that the appearance of gastric glands in stomach can be a good indicator to start weaning on yellowtail kingfish larvae. Therefore, the understanding of the histological development of fish gut can be used as a foundation to develop weaning strategy in larval fish rearing. Monitoring the recreational take of shark species of relevance to Commonwealth fisheries Katherine Cheshire and Peter Ward Australian Bureau of Agricultural and Resource Economics and Sciences (ABARES); Department of Agriculture, Fisheries and Forestry. Canberra ACT, Australia. www.daff.gov.au/abares. Email [email protected] This project was developed in recognition of the needs for developing policy and responding to management and conservation initiatives on Australian sharks. To better understand the impacts of recreational fishing on sharks, the key objectives were to: 1) identify sources of data on recreational interactions with frequently caught, nominated or high-risk shark species in Commonwealth waters and, 2) identify gaps in information on recreational shark catches to inform existing and future monitoring, management arrangements and conservation nominations. Recreational shark species of interest were defined through a series of literature searches. Recreational activities pertaining to sharks were identified through evaluation of databases and discussions with fishery scientists, managers and recreational fishers. A data catalogue of 35 relevant datasets has been compiled and reviewed from a combination of literature searches and more recent databases identified by state contacts and fishing experts. Evaluation of the catalogue and discussions with state fisheries representatives and recreational fishing experts revealed a series of knowledge gaps. Finally, future directions to fill these knowledge gaps and contribute to the available data that will help to monitor the recreational interactions with sharks are outlined. The present review has highlighted the need for more detailed examination of the available datasets to determine suitability for analyses for species of interest, and that development of a cost-effective survey focused on national recreational shark activities would also be valuable.


Habitat associations of native fish larvae in the main channel of a heavily regulated river system, Australia Katherine J. M. Cheshire1, Qifeng Ye2, Bronwyn M. Gillanders3 and Alison J. King4 1 Australian Bureau of Agricultural and Resource Economics and Sciences (ABARES); Department of Agriculture, Fisheries and Forestry. Canberra ACT, Australia. www.daff.gov.au/abares. Email [email protected] 2 South Australian Research and Development Institute (SARDI) Aquatic Sciences, Adelaide, South Australia. 3 The University of Adelaide, Adelaide, South Australia. 4 Charles Darwin University, Darwin, Northern Territory. Habitat availability is a critical component for the survival of early life stages of fish. Many recruitment models suggest that during low flows the main river channels of floodplain rivers do not provide adequate larval and juvenile habitat, however, recent studies have questioned this theory. This study describes the differing physical characteristics of three main channel habitat types (open water, still littoral and backwater habitats). We describe the observed variations in the larval assemblage and individual species abundances between these habitats during a low flow year in the Lower River Murray, South Australia. Backwaters and still littoral habitats had lower water velocity, were shallower and more structurally complex than open water habitats. Still littoral and backwater habitats were important main channel environments for developing larvae, even in a heavily regulated environment where the main river channel has relatively low velocities. Larval habitat associations may occur by either active or passive mechanisms. This study identified positive habitat associations for three native species (Australian smelt, hardyhead and carp gudgeon). Results suggest that positive associations are unlikely to be active selection of these habitats by larvae, but rather an active selection by adults as spawning sites, or potentially the passive deposition of larvae into these habitats from water currents. Important larval and juvenile habitats are often diminished in modified rivers. Results from this study suggest that suitability of habitats may also be influenced by the positioning around weirs, which may have significant implications for the restoration and management of habitats for native fishes. Measuring population change – comparison of blacklip abalone survey density estimates before and after commercial fishing Rowan C. Chick, Stephen Mayfield, Paul Burch, Sacha N. Turich and Richard McGarvey SARDI Aquatic Sciences, Adelaide, SA, Australia In 2011 the South Australian commercial abalone fishery harvested ~370 t of greenlip (Haliotis laevigata) and 460 t blacklip abalone (H. rubra) across three zones (Western, Central and Southern Zone), at a value of ~$AUD 28 M. Fishery-independent survey estimates of density are a key performance indicator in the assessment of abalone stock status in key fishing areas. Leaded-line transects (LL) are the principle method used to measure greenlip density, but have proved impractical for the assessment of blacklip in the WZ. In the WZ a stratified survey design and radial transect (cross drop; CD) survey method was developed. To compare the precision and efficiency of the LL and CD methods at detecting change in the density and biomass of blacklip populations, surveys were undertaken before and after fishing. CD and LL surveys typically recorded similar changes in density and biomass of legal and sub-legal sized blacklip after fishing. Although estimates from LLs were more precise, those from CDs provided more consistent measures of declines in legal density and biomass within fished areas and took less time to complete. Outcomes from this research identify improvements to the current design for surveying balcklip in the WZ. Account of a mass aggregation of Port Jackson sharks (Heterodontus portusjacksoni) at Point Cooke Marine Sanctuary, Victoria, Australia Andrew Christie NMIT (Northern Melbourne Institute of TAFE), Epping campus, Victoria, Australia. www.nmit.edu.au, [email protected] In January 2009, a mass aggregation of well over 100 quiescent female Port Jackson sharks (Heterodontus portusjacksoni) was noticed during a recreational snorkel at the Point Cooke Marine Sanctuary over two consecutive days in January 2009, after which all sharks evidently departed en masse. The habitat being utilized by these sharks on this occasion appeared to be different to that typically exploited by this species (which are traditionally caves and rock ledges or gutters that allow sharks to be tucked away and difficult to access), and instead consisted of intermittent basalt boulders and patches of sand, leaving the animals relatively exposed. Water depth was very shallow at approximately 1.5 to 2 metres deep. The reasons for the aggregation are ultimately unknown and open to speculation, but the sexual segregation that was demonstrated could have been indicative of a mass male-avoidance strategy. No sharks were observed to be actively foraging, and none of the distinctive spiral-shaped egg cases were observed, indicating that this aggregation was presumably not due to feeding or breeding motivations. The opportunistic observations conducted here may have shed some light on the behavioural patterns of this species, which may be more complex than first thought, as this type of behaviour has not been documented previously anywhere in Australia in this type of habitat. Observations of a sudden lack of sharks noticed at Ricketts Point Marine Sanctuary at around the same time (implying a short migration) point to the importance of friends groups in the monitoring of marine sanctuaries.


Eel-tailed catfish (Tandanus tandanus) – critical dispersers or curious explorers? Bernie Cockayne1, Kate Burndred1, Jonathan Marshall2, James Fawcett2 and David Sternberg3 1 Department of Environment & Resource Management, Mackay, QLD, Australia, 4740. [email protected] 2 Department of Environment & Resource Management, Dutton Park, QLD, Australia, 4102. [email protected] 3 Australian Rivers Institute, Griffith University, Nathan, QLD, Australia, 4111. [email protected] Movement patterns of T. tandanus were investigated using acoustic telemetry in a sub-tropical catchment; to assess how the species behaviour was related to flow regime, and specifically to detect habitat utilisation (e.g. riffles, waterholes) during periods of low flow. Fish were tracked over nine month periods (September – May), for two consecutive seasons (2010/2011 and 2011/2012), using a network of 23 receiving stations. In total, 160 T. tandanus were tagged, and 134 have been successfully detected to date. As this study is still underway, only preliminary results will be presented and discussed. Preliminary results show a high degree of variation in the nature of fish movements, from sedentary patterns (i.e. no movements) to extensive patterns (i.e. >10kms upstream and/or downstream). Extensive movements were typically initiated on the fall of the hydrograph following flow events (i.e. ~"0.5m/day); however, fish frequently undertook movements of various magnitudes irrespective of the hydrograph. To date, over half of the tagged fish have been detected utilising riffles to move between waterholes at least once throughout the tracking season. No significant differences in movement patterns have been detected between fish size, sex or waterhole location. Future analysis will interrogate the data more thoroughly, and provide some insight into the ecological drivers behind these variable movement patterns. Are such movements critical, or are these fish just exceptionally curious? Environmental Water Allocations in regulated lowland rivers may encourage offstream movements and spawning by common carp, Cyprinus carpio: implications for wetland rehabilitation Anthony J. Conallin1,2, Ben B. Smith2,3, Leigh A. Thwaites2, Keith F. Walker1 and Bronwyn M. GillandersA 1 School of Earth and Environmental Sciences, The University of Adelaide, Adelaide, SA, Australia. 2 Inland Waters and Catchment Ecology Program, SARDI Aquatic Sciences, West Beach, SA, Australia. 3 Present address: Policy and Strategy Division, Department for Water, Adelaide, SA, Australia. Environmental Water Allocations (EWAs) are used to enhance native flora and fauna in regulated rivers, but may also benefit alien invasive species. We examined the invasion and spawning risk posed by common carp (Cyprinus carpio) during an EWA delivered from the River Murray to a flow-through wetland from June–December 2008. Offstream movements of fish and turtles were monitored continuously via the inlet and outlet creeks. Long-necked turtles (Chelodina longicollis. n = 129) dominated at the inlet where few fish were collected (n = 24), but much larger numbers of common carp in prime spawning condition (n = 4709), alien goldfish (Carassius auratus, n = 1201) and native bony herring (Nematalosa erebi, n = 93) were attracted to the outlet and displayed distinct movements. Carp movements began in August, when water temperatures increased above the annual minimum (10.6°C in river; 9.2 °C at outlet), and peaked in mid-September prior to spawning. The timing of EWA deliveries potentially could be manipulated to reduce carp invasion and spawning potential while providing some advantage to native fish, but the benefits could be limited outside of the natural flooding period (August–November). Within this period, carp management will be necessary to maximise ecological benefits. Acoustic freshwater fish tracking programs: How managers use this technology to inform their decision making John Conallin1, Lee Baumgartner2, Ian Wooden2 and Wayne Robinson3 1 Murray Catchment Management Authority, Deniliquin, NSW, Australia. [email protected] 2 Narrandera Fisheries Centre, Narrandera, NSW, Australia. 3 Charles Sturt University, Albury, NSW, Australia. The Edward-Wakool (E-W) system forms a series of over 1500 kms of rivers and small creeks including the forests of Barmah-Millewa, Koondrook-Perricoota and Werai. The system contains significant populations of native fish including the large bodied fish; Murray cod, silver perch, golden perch and the pest species carp. The Murray Catchment Management Authority and partners have implemented a strategic adaptive management process with a focus on flows, both consumptive and environmental. A vision for the system has been set by all stakeholders; Self sustaining communities of native fish within a vibrant rural community. Fish communities within the E-W system are being used as the primary indicator for these environmental flow programs. This has created many challenges for managers, scientists and community in how to meet this vision, and find a balance between consumptive and environmental considerations. As a starting point to inform and eventually meet this vision, environmental flow experiments are being conducted to evaluate fish responses and third party impacts in relation to targeted flow regimes (e.g. pulse flows, low flows). Between 2010-11, over 150 large bodied-fish of four species (Murray Cod, golden perch, silver perch, and carp) have been acoustically tagged and an acoustic array system established to track movements throughout the system. This presentation will concentrate on the management implications from the monitoring, and how this scientific data is used in management planning and management-based research. The ability for managers, scientists and community to collaborate to reach outcomes will also be discussed. 36 ASFB & OCS 2012 Joint Conference & Symposium Sebel Playford Hotel, Adelaide, South Australia 15-18 July 2012

Unusual fatty acid profiles of manta rays and whale sharks suggest they might not predominantly feed on crustacean zooplankton Lydie I.E. Couturier1,2, Christoph A. Rohner3,4, Anthony J. Richardson2,5, Simon J. Pierce3,6, Andrea D. Marshall3,6, Fabrice R.A. Jaine2,4,7, Kathy Townsend7, Mike B. Bennett1, Scarla J. Weeks4 and Peter D. Nichols8 1 School of Biomedical Sciences, The University of Queensland, St Lucia QLD 4072, Australia. 2 Climate Adaptation Flagship, CSIRO Marine and Atmospheric Research, Dutton Park QLD 4102, Australia. 3 Manta Ray and Whale Shark Research Centre, Marine Megafauna Foundation, Praia do Tofo, Inhambane, Mozambique. 4 Biophysical Oceanography Group, School of Geography, Planning and Environmental Management, The University of Queensland, St Lucia QLD 4072, Australia. 5 Centre for Applications in Natural Resource Mathematics, The University of Queensland, St Lucia QLD 4072, Australia. 6 ECOCEAN USA, Inhambane, Mozambique. 7 School of Biological Sciences, The University of Queensland, St Lucia QLD 4072, Australia. 8 CSIRO Marine and Atmospheric Research, Hobart TAS 7000, Australia. We examined for the first time the feeding ecology of the whale shark Rhincodon typus and the manta ray Manta alfredi in terms of their fatty acid (FA) signature profiles. FA signature analysis has been increasingly and successfully used as an indirect method to assess dietary preferences and trophodynamics of marine animals. Manta ray and whale shark FA signatures had high levels of #6 polyunsaturated fatty acids (PUFA), dominated by arachidonic acid (20:4#6; 12-18%of total FAs), and had comparatively low levels of the essential #3 PUFAs eicosapentaenoic acid (20:5#3; ~1%) and docosahexaenoic acid (22:6#3; 3-11%). Both species had an #3/#6 ratio of 25 km). Individuals displayed distinct diurnal shifts in habitat use, using shallower habitats during the night and deeper areas during the day. R. tapirina are capable of complex migratory behaviour and fast, long-distance movements. Knowledge of the species’ migratory capabilities and interaction with offshore habitats may help explain the high inter-annual variation in population abundance and biomass. Estimating fish species richness from underwater video and netting in remote Australian waterholes Brendan C. Ebner1,2 and David L. Morgan3 1 Tropical Landscapes Joint Venture, CSIRO Ecosystem Sciences & TropWATER (James Cook University) Atherton, Queensland, Australia 2 Australian Rivers Institute, Griffith University, Nathan, Queensland, Australia 3 Freshwater Fish Group & Fish Health Unit, Murdoch University, Murdoch, Western Australia, Australia 1 Corresponding author. Email: [email protected] The rapid assessment of biodiversity is an important task in the sustainable management of ecosystems. Baited remote underwater video stations (BRUVs) have been successfully applied in high visibility marine ecosystems for this purpose, particularly at depths where conventional survey methods are impractical. We aimed to determine if BRUVs and unbaited remote underwater video stations (UBRUVs) provide an effective means of complementing conventional netting techniques for rapid survey of fish communities in large waterholes in a remote Australian river. Species richness records from replicated deployments of BRUVs and UBRUVs in shallow (1 m) water were compared with those obtained from using fyke nets, gill nets and beach seines. Maximum species richness was achieved through a combination of conventional netting and camera based techniques. BRUVs and UBRUVs provided versatile techniques that were effective at a range of depths and habitats, contrasting each of the netting techniques. We conclude that cameras warrant application in aquatic areas of high conservation value including where threatened species are the focus of monitoring or if such species would otherwise be encountered as by-catch by destructive techniques.


Persistence of Spangled perch in the southern Murray-Darling Basin post 2011 flooding Iain Ellis Murray-Darling Freshwater Research Centre, Mildura, Victoria, Australia. Email: [email protected] The Spangled perch (Leiopotherapon unicolour) is one of Australia’s most widespread native freshwater fish, occurring in warmer freshwater systems across most of northern Australia. It’s a tough fish capable of surviving in rivers, lakes, billabongs, drains and even wet paddocks and wheel ruts. Although Spangled perch occurs in the Darling River system as far south as the Menindee Lakes, it is considered a rare vagrant in southern waters of the Murray Darling Basin (down to and including the Murray River and its tributaries). The species has only been recorded in the Murray River after extensive flooding in northern rivers. Cold water temperatures are considered to limit its survival in the Murray River system, with reduced survival below 7°C. This presentation discusses the occurrence and persistence of Spangled perch in the Murray River and Lower Darling floodplain systems, after dispersal in 2010/11 floodwaters. Although the data presented is observational, it demonstrates the species is capable of surviving winter in the Murray and Lower Darling. Further, monitoring in Lake Hawthorn near Mildura has demonstrated that Spangled perch have successfully spawned and recruited over two successive winter seasons. Otolith shape and elemental composition: Complementary tools for stock discrimination of Mulloway (Argyrosomus japonicus) in Southern Australia Greg J. Ferguson1, Tim M. Ward1 and Bronwyn M. Gillanders2 1 South Australian Research and Development Institute (Aquatic Sciences), West, Beach, South Australia, Australia. [email protected]. www.sardi.sa.gov.au. 2 University of Adelaide, School of Earth and Environmental Sciences, Adelaide, South Australia, Australia. www.marinebiology.adelaide.edu.au/ The sciaenid Argyrosomus japonicus is targeted by commercial fishers and is regarded as an icon species by recreational fishers. In South Australia, A. japonicus is managed as a single stock although biological information suggests that regional differences may occur. Here, the stock structure of A. japonicus in South Australia was investigated using two complementary methods: (i) elemental signatures (Sr:Ca, Ba:Ca, and Mg:Ca) from the otolith edge, and (ii) shape characteristics (otolith morphometrics and overall shape) of whole otoliths. Comparison of elemental signatures indicated that Ba:Ca levels were low in the western coast, intermediate in the central coast and high in the eastern coast. Constrained Canonical Analysis of Principal Coordinates (CAP) allocated elemental concentrations of individual otoliths to regions with 100, 100, and 87% success for western, central and eastern coasts respectively. Otolith shape (elliptical Fourier descriptors and morphological indices) supported results from the elemental study with allocation success of 85, 57, and 85% for western, central and eastern coasts respectively. Whilst trace-element analysis of the otolith edge provided very high classification success and gave a snapshot of differences between groups from different geographic areas, shape analysis indicated that these discrete groups of fish experienced different environmental conditions over a long period of time. Possible sub-structuring of the population of A. japonicus in South Australia has implications for sustainable management. Empty slums and crowded mansions: scaling up cryptic density dependence in temperate reef fish John R Ford1, Jeffery S Shima2 and Stephen E Swearer 1 Department of Zoology, Melbourne University, Victoria, Australia. [email protected] 2 School of Biological Sciences, Victoria University of Wellington, Wellington, New Zealand Density dependence is well recognized as an important process regulating populations. However the detection of density dependence in fish populations is often confounded by heterogeneity in habitat quality, known as cryptic density dependence. Higher quality habitat can support higher densities of individuals before resources are saturated or become limiting. In reef fish, cryptic density dependent regulation has been observed only on short time scales immediately postsettlement, and on small spatial scales of individual reefs. In this study we examined the mortality of a shoaling temperate reef fish, Trachinops caudimaculatus, on 16 large reefs within Port Phillip Bay, Victoria over a 12-month period. Using habitat quality estimates of refuge availability, rugosity and tidal flows (as an estimate of zooplankton delivery), we investigated how the strength of density dependent mortality varied amongst sites. In summer months immediately post-settlement, mortality was significantly related to the combined effects of density, refuge availability and rugosity, suggesting shelter limitation when densities were highest. In winter, mortality was related to density and tidal flow, suggesting food limitation in colder months. Cryptic density dependence can therefore scale up to large reef systems over longer temporal periods. The nature of habitat ‘quality’ is dynamic, and reflects the limiting resources experienced by populations at a given time and place. Observing how populations respond to natural fluctuations in density and resource availability will aid in our understanding of persistence in the face of human impacts.


Can spatial differences in the chronological structure of otoliths provide insight into the origins and large-scale movement of Snapper (Pagrus auratus)? Anthony Fowler and Michael Steer South Australian Research and Development Institute, Adelaide, South Australia [email protected], [email protected] In recent years, South Australia (SA) has become the dominant contributor to the national catch of Snapper, reflecting significant increases in catches and catch rates. This partly relates to considerable changes in the spatial structure of the fishery. However, the influence of large-scale fish movement on these changes is poorly understood. The aim here was to assess whether the physical characteristics of the incremental structure of Snapper otoliths could help determine the regions of origin and age-related movement patterns at the regional scale. Transverse sections of otoliths were analysed from eight-year old fish sampled from six geographic regions that incorporated several hundred kilometres of the coastlines of SA and Victoria. Increment widths across otoliths were measured whilst the optical densities of the individual opaque and translucent zones were quantified. Analysis of cross-otolith increment widths gave three results: the cross-otolith trajectories for several regions differed from the first increment onwards; for several other regions they diverged after a few years; whilst for three adjacent regions no differences were apparent. Regional comparisons of cross-otolith estimates of optical density were less conclusive, but provided some age-specific differences. They suggested that fish from some regions have separate origins and are unlikely to have inter-mixed. For others, the data are consistent with a shared origin and subsequent separation and divergence after a few years. This study has demonstrated that the physical characteristics of otoliths provide age-related phenotypic data that contribute to understanding the origins, movement and stock structure for Snapper. Acoustic tracking of New Zealand white sharks reveals spatial preferences and small-scale movements in an island chain Malcolm Francis1, Clinton Duffy2, Warrick Lyon1 and Kina Scollay3 1 National Institute of Water and Atmospheric Research, Wellington, New Zealand, [email protected] 2 Department of Conservation, Auckland, New Zealand 3 Ocean Answers Ltd, Picton, New Zealand Forty-five white sharks (Carcharodon carcharias) have been tagged with coded acoustic tags around an island chain off north-eastern Stewart Island, southern New Zealand, during the last two years. Their movements around the island chain, where they aggregate to feed on New Zealand fur seals, have been monitored with Vemco acoustic receivers. Data from 25 sharks tagged in the first year of the study show that most remained in the region for three months between tagging in March–April 2011 and June 2011, at which time they departed on ocean migrations to tropical waters. Most sharks departed by late June with a few remaining until mid July. Sharks began returning in late spring and early summer, and more than 40% were recorded acoustically or visually near their tagging site by March 2012. Hot spots of shark presence have been identified, and individual sharks showed preferences for different parts of the island chain. Most sites showed a diurnal cycle in shark attendance, with some sites being preferred during the day and some at night. Small-scale spatial and temporal movement patterns are being analysed to identify variation among sharks and through time. Investigating the effects of intra- and inter-specific competition between native and introduced fish using RNA:DNA ratios as a biochemical indicator of condition Peter Fraser, Christopher Izzo and Bronwyn Gillanders School of Earth and Environmental Sciences, University of Adelaide, South Australia, Australia Competition between native and introduced species is one of the major mechanisms threatening the biodiversity of native assemblages. Competitive interactions between Galaxias olidus (mountain galaxias) and Oncorhynchus mykiss (rainbow trout) were examined in relation to feeding and condition. G. olidus is a small-bodied teleost native to southeastern Australia, and O. mykiss is an introduced species that is a popular sportfish. O. mykiss populations in South Australia are maintained by regular releases of hatchery-reared fish. The quantity of food eaten, as well as condition of fish, as measured from RNA:DNA ratios of white epaxial tissue, were compared among treatments to assess the impact of intra- and inter-specific competition. The volume of food consumed by G. olidus was significantly lower when trout were present. The condition of G. olidus where trout were also present at high density was significantly lower than in control treatments. Significant inter-specific competition appears to occur between these two species and exposure of G. olidus to competitive pressure from O. mykiss is likely to have an impact on the fitness of G. olidus. The use of RNA:DNA ratios as an empirical measure of the impacts of competition was a useful tool for assessing the influence of competitive effects on condition of fish. This method is especially useful when examining small-bodied fish with slow growth/attrition rates where traditional methods for estimating condition (e.g. Fulton’s K) are impractical, especially for experiments over short time periods.


Can a threshold value be used to classify Chondrichthyan reproductive modes: review and validation using an oviparous species, Heterodontus portusjacksoni Holly A. Frazer1, Megan Ellis1 and Charlie Huveneers1,3 1 School of Biological Sciences, Flinders University, Adelaide, South Australia, Australia 2 Gladstone Ports Corporation, Gladstone, Queensland, Australia 3 Threatened, Endangered, and Protected Species subprogram, SARDI – Aquatic Sciences, Adelaide, South Australia, Australia The maternal-embryonic nutritional relationship in viviparous chondrichthyans has been poorly explored. Consequently, accurately discerning between their different reproductive modes is difficult; especially lecithotrophy from incipient histotrophy. This present study is the first to assess weight changes throughout embryonic development of an oviparous chondrichthyan other than Scyliorhinus canicula. Heterodontus portusjacksoni egg cases were collected and used to quantify the gain or loss of wet weight, dry weight, water content, inorganic and organic matter from freshly deposited eggs (without macroscopically visible embryos) to near full-term embryos. An organic weight loss of ~ 40% found from this study is approximately double the values previously obtained for S. canicula. This raises concerns for the validity of the current threshold value widely used to discern between lecithotrophic and matrotrophic species. Accordingly, 26 studies published in the primary literature between 1932 and 2012, addressing the maternal-embryonic nutritional relationship in sharks, were reviewed. Weight change values reported for over 20 different shark species were synthesised and recalculated, revealing multiple typographical, calculation, transcribing, and rounding errors across many papers. These results suggest that the current threshold value of -20% established by previous studies is invalid and should be avoided to ascertain the reproductive mode of aplacental viviparous species. Oriental weatherloach, Misgurnus anguillicaudatus, in South Australia: a risk assessment Josh F. Fredberg1 and Dr. Leigh Thwaites1 1 Invasive Species sub-program; Inland Waters and Catchment Ecology Program, SARDI, Aquatic Sciences, Adelaide, South Australia 5022. ([email protected]; [email protected]) Until the recent drought breaking floods throughout eastern Australia (2010/11) there were no recorded catches of oriental weatherloach, Misgurnus anguillicaudatus, within the South Australian section of the Murray River. However, post-flood sampling of wetlands and floodplains confirms the species distribution has extended into South Australia with a total of forty one reported captures. The species is currently established across two Australian states (Victoria & NSW) and one territory (ACT) and is listed as noxious across all jurisdictions. Although there have been reported catches in South Australia there is currently no data to suggest the species has established. Due to this recent incursion and unknowns associated with the establishment/spread of the species, the world class screening software, Fish Invasiveness Scoring Kit (FISK v.2.0) followed by the Non-native Species Risk Assessment (NAPRA v.2.61) were used to assess, rank and score the environmental, economic and social impacts/costs associated with the species within South Australia. The results indicate a high risk of establishment and suggest several potential impacts including; competition for spawning sites with native fish, disturbance or predation of both fish and frog eggs, competition for food and shelter, alteration of habitat and decreased water quality. However, these impacts are largely speculative and several knowledge gaps regarding the species ecological impacts and interactions with native flora and fauna still exist. Further research is required to quantify potential impacts and to determine the most appropriate management/control strategies for oriental weatherloach in South Australia. Radio transmitters can affect the feeding behavior and the movement of freshwater stingrays (myliobatiformes, potamotrygonidae)? Domingos Garrone Neto1, Carolina Bonfim Tiveron1, Rafael dos Santos2, Lisiane Hahn3 and Otto Bismarck Fazzano Gadig1 1 ELASMOBRASIL – Elasmobrach Research Laboratory, UNESP – São Paulo State University, 11330-900 São Vicente/SP, Brazil, [email protected], [email protected], [email protected]; 2 ACQUA MUNDO – Guarujá Aquarium, 11440-531 Guarujá/SP, Brazil, [email protected]. 3 NEOTROPICAL – Environmental Consulting, 99074-210 Passo Fundo/RS, Brazil, [email protected]. Despite studies of elasmobranch using biotelemetry have increased in the last decades, few data are available about the effects of such equipments on these animals’ behavior. In this sense, was tested the hypothesis that electronic tags affect the detection of prey by potamotrygonids and interfere in its swimming performance. Thus, two experiments were conducted, using captive individuals of Potamotrygon falkneri: i) stingrays’ response against offering of live shrimps and the possible effects of radio tags in this process, and ii) stingrays’ behavior before and after radio tagging. For the first experiment were used two aquariums, each one containing one male and one female of Potamotrygon falkneri, where shrimps were offered inside grids in two phases: a) without and b) with the presence of radio tags between the stingrays and shrimps. For each phase, four observation sessions of ten minutes were made, totalizing 480 minutes. For the second experiment were used six stingrays maintained in a single tank, observed in two phases of 32 hours: a) before and b) after of three individuals having fixed tags on their dorsal region. In both phases of the first experiment the feeding behavior of the stingrays showed no difference, with Potamotrygon falkneri attacking the shrimps in the absence and presence of radio transmitters. In both phases of the second experiment the stingrays’ diel movements were similar, with activity predominantly nocturnal. The swimming pattern of the tagged individuals and their interactions with the others stingrays were apparently not affected, annulling the hypothesis herein tested.


Spatial grouping and temporal trends in otolith chemistry of an estuarine fish Ana Judith Giraldo, Travis S. Elsdon and Bronwyn M. Gillanders University of Adelaide, Adelaide, SA, Australia Elemental concentration in otoliths provides a unique opportunity to discriminate among fish that live in different habitats, and to estimate population structure. Therefore, we examined spatial and temporal patterns in otoliths of juvenile 0" black bream (Acanthopagrus butcheri), to discriminate stocks of fish living in different estuaries. Fish were sampled in up to 13 estuaries of Kangaroo Island and the Fleurieu Peninsula each year over a five year period (2008 – 2011). Otoliths were examined to determine if individual estuaries or groups of estuaries differed in chemical concentrations (tags), and to examine inter-annual variation in chemical tags. Tags differed among individual estuaries and in some cases adjacent estuaries shared similar chemical tags. Differences in chemical tags were detected among all estuaries in two of the year’s comparisons. Similarities in otolith tags were detected for five of the seven estuaries in 2010 and 2011. Temporal differences in chemical tags were detected among years for several estuaries; however, there were no clear trends in the differences between years. The results highlight that the population of black bream from different estuaries or group of estuaries have unique chemical tags that can be used to trace cohorts of fish. Chemical tags in juvenile black bream can therefore be used to estimate connectivity, population movements, and the function of estuaries as nursery areas for this species in subsequent years. Research and development of novel by-catch reduction technologies in a demersal trawl fishery Daniel Gorman1,Nathan Bicknell2, Cameron Dixon1, Graham Hooper1 and Shane Roberts3 1. South Australian Research and Development Institute, West Beach, South Australia, Australia 2. Seanet, Port Adelaide, South Australia, Australia 3. Primary Industries and Regions South Australia, Adelaide, South Australia, Australia The incidental capture of juvenile and non-target species (collectively termed ‘by-catch’) is an important management issue for penaeid prawn fisheries. The aim of this study was to research and develop by-catch reduction technologies within the South Australian Penaeus (Melicertus latisulcatus) trawl fishery. We describe the developmental process by which novel net designs were tested with industry support. Fishery-independent surveys and commercial trials showed that gear designs which utilise square-mesh (T90) cod-ends and rigid exclusion grids were able to reduce the catch of small prawns (28% reduction), fish (25%), sponge (87%) and elasmobranchs (100%) when compared to traditional diamond-mesh designs. Of particular importance to industry, was that these improvements were achieved with no significant reduction to the catch rate of large prawns. Results were validated through replicated testing done across locations and seasons and with simple underwater video equipment that also provides a means of communicating research outcomes to stakeholders. Improved gear technologies have the potential to provide environmental benefits (i.e., reducing the proportional capture and mortality of by-catch) as well as substantial economic incentives such as reduced handling time, improved catch quality and reduced fuel costs. Our recommendations have been adopted by management and industry and form part of management policy that continues to improve the sustainability of demersal trawl fisheries with South Australia. Do estuarine artificial reefs enhance fish biodiversity and recreational angling opportunities? Charles A. Gray1,2, F. Ochwada-Doyle1, 2, M. Lowry1, 3 and H. Folpp1, 2 1 School of Biological, Earth and Environmental Science, University of New South Wales, Australia; 2 Cronulla Fisheries Research Centre, Australia; 3 Port Stephens Fisheries Centre, Australia [email protected] Estuaries are subjected to many anthropogenic impacts but still contain diverse fish assemblages supporting valuable fisheries. Artificial structures such as reefs are used globally for habitat rehabilitation and enhancing biodiversity, fisheries production and fishing opportunities. Artificial reefs have been deployed in several estuaries in NSW to enhance local recreational fisheries. Here, we explore the value of these structures in terms of biodiversity and fisheries enhancement in two estuaries by comparing artificial reefs to other habitats in terms of: (1) the composition and abundance of fish fauna, (2) levels of recreational fishing effort, and (3) the number and species composition of retained catches of recreational anglers. This research was done by (1) surveying fish assemblages associated with artificial reefs and surrounding habitats using Baited Remote Underwater Video (BRUV’s) and Underwater Visual Census using SCUBA, (2) surveying the spatial dynamics of recreational fishing effort, and (3) interviewing recreational anglers and surveying catches. We found that the abundance and composition of fish assemblages differed between artificial and natural reefs in each estuary and that the diversity of species and the relative abundances of several species were elevated on artificial reefs. In comparison, there were no significant differences in catch rates of key angling species among habitats. Levels of recreational fishing effort were low on artificial reefs. Estuarine artificial reefs can provide suitable habitat for a diverse range of fish species and potentially provide enhanced fishing opportunities for recreational anglers.


Close Kin Relationships provide a Fishery Independent Approach for Estimating Southern Bluefin Tuna Spawning Stock Biomass Peter Grewe1, Mark Bravington2, Campbell Davies3, Peta Hill4, Rasanthi Gunasekera and Danielle Lalonde Commonwealth Scientific and Industrial Research Organisation (CSIRO), Hobart, Tasmania, Australia. 1 Commonwealth Scientific and Industrial Research Organisation, (CSIRO Marine and Atmospheric Research) Hobart, Tasmania, Australia, email: [email protected] 2 Commonwealth Scientific and Industrial Research Organisation, (CSIRO-CMIS), Hobart, Tasmania, Australia 3 Commonwealth Scientific and Industrial Research Organisation, (CSIRO Marine and Atmospheric Research), Hobart, Tasmania, Australia 4 Commonwealth Scientific and Industrial Research Organisation, (CSIRO Marine and Atmospheric Research) Hobart, Tasmania, Australia Estimation of standing stock biomass is a critical measure for management of fisheries stocks and setting total allowable catch (TAC) quotas. For southern bluefin tuna (SBT), conventional stock assessment methods have provided a reasonable estimate of relative abundance of SBT today versus near the start of exploitation. However, estimates of absolute abundance are much less precise, and quite sensitive to different assumptions about data reliability (eg. unreliable reporting of tag returns and changes in fish targeting practices). In turn, predictions of the effects of different TACs on future stock size are difficult to estimate. We describe a method for estimating the absolute spawning stock size of SBT, based on genetic identification of parent-offspring matches in adults sampled from the spawning grounds in Indonesia and juvenile fish from the Great Australian Bight. The method is related to mark-recapture, and provides an estimate of true adult numbers (not the unrelated genetic concept of Ne or effective population size). No catch or CPUE data is used, so the estimate is not subject to biases and interpretational problems associated with recent SBT assessments. We explain the statistical basis of the method, comment on its robustness, and describe progress on analysis of DNA from 14,000 fish profiled using 24 microsatellite loci. The underlying dynamics of a simple CPUE based fisheries harvest control rule Malcolm Haddon and Natalie Dowling CSIRO Wealth from Oceans, Castray Esplanade, GPO Box 1538, Hobart, TAS, 7001, Australia. [email protected] Providing management advice for relatively data poor commercial fisheries is a problem worldwide. An array of alternative methods has been proposed and one of the simplest is to consider the gradient of a simple regression of catch rates against a given number of years. The idea is that the catch or effort can be increased or decreased in some defined manner depending on whether the gradient of the regression is positive or negative. Using an age-structured simulation framework, conditioned on the contrasting biology of species such as tiger flathead and pink ling, the stock dynamics underlying the successful operation of this simple harvest control rule are elucidated. Its successful operation depends on the relationship between exploitable biomass and catch rates being approximately linear. The degradation in the performance of this CPUE based control rule as the relationship between biomass and CPUE becomes less linear, along with the associated risks for a stock, are also demonstrated. Age, growth and reproductive biology of Australian blacktip shark, Carcharhinus tilstoni, from the Great Barrier Reef Marine Park Alastair V Harry1, Colin A Simpfendorfer1 and Andrew J Tobin1 1 Centre for Sustainable Tropical Fisheries and Aquaculture & School of Earth and Environmental Sciences, James Cook University, Townsville, QLD The Australian blacktip shark, Carcharhinus tilstoni, is a moderately large (