King George Whiting Tagging Project
A recreational angler based tagging program to understand the movements of Victorian King George Whiting to their spawning areas.
Funded by the Victorian Recreational Fishing Licence Grant Scheme
(Please see News page for latest updates on the project)
King George Whiting caught by fishers in Victorian bays are juveniles up to the age of 4 years that are too young to spawn. Whiting older than this move out of the bays onto the coast, and tend to be older and larger in western Victoria. Until recently the only known spawning area for Whiting was the Investigator Strait area, north of Kangaroo Island in central South Australia (SA), where Whiting are up to nearly 20 years of age. An important question for the sustainability of the Victorian King George Whiting fishery is whether Victorian fish migrate to the known South Australian spawning ground, and are therefore subject to fishing pressure from the targeted fishery for large whiting in that area. Computer modelling studies have suggested that King George Whiting larvae drift to Victorian Bays from an area approximately between Portland and Beachport in south-eastern SA, suggesting that Victorian Whiting may be spawning in that area.
A recent research project on stock structure of King George Whiting based on otolith (earbone) chemistry and genetics funded by the FRDC and the RFL has provided strong evidence that Victorian Whiting are not spawned in the known Investigator Strait spawning area in SA, and that our adults are not migrating to that area for spawning. A new spawning ground for King George Whiting was found off the coast of north-west Tasmania, but these fish are genetically distinct from Victorian Whiting. The results of the study support the original modelling in suggesting that the most likely scenario is that Victorian Whiting are spawning in far western Victoria to south-eastern SA. Otolith chemistry of larger whiting from western Victoria is consistent with what might be expected of fish from Victorian Bays.
There is now an opportunity to partner with recreational fishers in a tagging program to confirm the movement of Whiting from Victorian bays to the likely spawning area. This project will partner with fishing clubs that have active whiting fishers and there will be a coordinating person within each club. There is an increasingly active recreational fishery for larger Whiting along the coast from far western Victoria into south-eastern South Australia, so that chances of recapturing tagged Whiting are much higher than in the past. This project will coordinate recreational fishers in tagging up to 2000 Whiting in Port Phillip Bay and Western Port as well as on the Victorian coast in the first year of the project (2016/17), with additional tagging also occurring in the second and third years of the project (2017/18, 2018/19).
Recreational fishers will tag whiting using T-bar tags, which have been successfully used to tag King George Whiting in South Australia. A short video is available on the following link showing the tagging method, https://youtu.be/vsBiQFqqvlc. T-bar tags are applied with a tagging gun, and are positioned in the flesh beneath the first dorsal fin. The tag is inserted on an angle about 10-15 mm from the start of the dorsal fin so that the tag streams backward and the T-bar is under about the 3rd or 4th dorsal spine.
Fishers tagging Whiting will need to record the tag number for each fish tagged, as well as the date and location (general location and ideally lat. and long. from GPS) and the length of the fish (fork length (preferably) or total length). Along with reporting the tag number, recaptures will include information on re-capture date and location, as well as fish length (fork length (preferably) or total length). Tagging and recapture information can be communicated through a dedicated project email address: firstname.lastname@example.org or by phone (03) 52583686 or mail (G. Jenkins, VMSC, PO Box 114, Queenscliff Vic 3225). If possible, the frozen frame of the recaptured fish will be retained to be collected so that project scientists can assess the age and reproductive condition of re-captured fish. For fishers aware of the program there is also the option of returning a tagged fish to the water after recording details of tag number location etc (especially if caught in Port Phillip or Western Port). A prize lottery (fishing tackle) will also be established for re-capture returns as an additional incentive.
The results of the project will contribute greatly to our understanding of the biology and life history of King George Whiting, potentially for the first time confirming the spawning area for Victorian whiting. In addition, the results will contribute to the sustainable management of the King George Whiting fishery by providing further information on the relationship between the Victorian and South Australian fishery stocks, and whether the sustainability of the Victorian fishery is affected by the activity of the South Australian fishery. Finally, as well as the research and management value of the project, there is a great science extension opportunity where recreational fishers can contribute substantially to the research and at the same time learn about the biology and life history of this iconic species.