JCU Predator Tagging Project
What is happening?
Project to assess the movements and growth of inshore predators (sharks and fish, including blacktip, whaler and hammerhead sharks, and grunter, threadfin salmon and queenfish), including examination of importance of protected zones. This will involve catching tagging and releasing sharks and fish in the Townsville region (Cleveland, Halifax and Bowling Green Bays). Animals will be caught by researchers operating in Blue and Yellow zones. Employing methods (multi-hook research lines and short set gillnets) to ensure minimal effects on animals to ensure tagged animals are released in best condition. Gillnets will always be constantly attended to ensure the safe release of species of conservation concern. Some animals will be injected with a dye to mark their backbone or ear bones to help in ageing studies.
Can fish injected with dyes be eaten?
The dyes injected into sharks and fish are injected at very low doses and pose no threat to human health.
Why is this research happening?
To help with the management of inshore resources and to understand the effectiveness of Conservation Park (yellow zones) in ensuring the sustainability of populations of inshore shark and fish species.
Where is it happening?
Animals will be released in Cleveland, Halifax and Bowling Green Bays (Townsville region). However, some of the tagged animals will probably swim beyond these bays, and potentially be caught anywhere along the Queensland east coast.
When is this happening?
The project is scheduled to start in February 2007, and will run for at least two years. Tagged animals may be caught for many years to come, and should be reported using the same protocols as outlined below.
Are animals being retained?
This project will retain fish and sharks to provide specimens for biological research. This research will provide important information on the reproduction, age, growth and feeding of inshore species. For the gillnet and multi-hook line gears, only animals that are dead in the gear will be retained, and researchers will work hard to minimise these occurrences. Trawl surveys will retain samples of smaller fish to study the prey of the larger predatory fish. This will help understand the dynamics of predator populations.
Who is involved?
The research is being carried out by staff and students of the Fishing and Fisheries Research Centre at James Cook University. The project has been developed in collaboration with the Great Barrier Reef Marine Park Authority and Queensland Department of Primary Industries & Fisheries. Funding for the project has been provided by the Australian Government’s Marine and Tropical Science Research Facility, James Cook University and the Fisheries Research and Development Corporation.
How can people help?
Report all captures of sharks and fish tagged with JCU tags (different colour to AusTag tags – normally white for JCU) on their tagging hotline (07 4781 5973) or via email (fishtag@jcu.edu.au); where possible keep the fish (whole or frame) for collection by F&F personnel. The tagging hotline will operate 24 hours a day, but will be staffed only during normal office hours. There will be a small reward offered for tag returns.
What if you see researchers operating in Yellow Zones?
This research requires the tagging of sharks and fish in Yellow Zones. Whenever research activities are being carried out vessels involved will be clearly marked as Research Vessels. Researchers will always carry copies of their permits, and GBRMPA and QDPI&F will be informed prior to commencement of activities. The only animals kept during this research will be those that do not survive during capture. The fishing gear and techniques have been designed to maximise the survival of sharks and fish.
Results so Far
The research team has tagged over 200 sharks and fish and has already had a number of interesting recaptures. The image below shows some of these. A number of scalloped hammerheads, blacktip sharks and spottail sharks have been recaptured in close proximity (less than 8 km) to their release sites, even after periods of up to 8 months. Other sharks have moved further. A whitespotted guitarfish tagged outside the Ross River in January was recaptured and again released by a commercial fisher north-east of the Haughton River in November. A juvenile bull shark tagged in the same location in April moved northwest and was recaptured at Paluma Shoals in October.
More information will become available as the project continues…