Rock lobster, abalone and dive fishing restrictions apply in two long-spined sea urchin research areas,
Elephant Rock and
The incursion of the long-spined sea urchin, or
Centrostephanus, into Tasmanian waters represents a range extension for this species that is most likely associated with climate change, and the warming of waters off the east coast.
Options such as eradication are simply not viable and achievement of such an outcome is impossible. Rather, action that might mitigate or ameliorate the impact is more likely to have some impact. However, there is no 'silver bullet' identified for this issue.
A major research project by the Institute for Marine and Antarctic Studies, or IMAS, to investigate potential management strategies is now completed.
A key aspect of the ongoing research is the interaction of rock lobster and
Centrostephanus. The research indicates that large rock lobsters predate on large long-spined sea urchins, and are thus one of the few know predators on this long spined urchin.
Part of this research involved measuring the impacts of large lobsters on
Centrostephanus in existing barrens and also where
Centrostephanus are present but have not yet formed barrens - in what are called incipient barrens.
These trials were facilitated by the Department declaring two research areas where fishing has been limited and the take of fish by diving, pot or ring is prohibited (no take of lobsters). This research saw the translocation of significant numbers of large lobsters into the two areas on the east coast and the impacts were monitored over time.
The two areas set aside are: Elephant Rock (near St Helens); and, Southerly Bottom (in
North Bay) on the easterly side of the Forestier Peninsula.
However, as the research project was ending, it was identified that the research areas provided a longer term opportunity to research this issue and monitor the changes in these areas. Significant resources have been expended in this research and maximising the long term benefit is important.
However, if the areas are to remain closed, it is also important that the research is conducted in those areas. A large investment has been made in these areas and a continued time series and monitoring of these areas will be informative.
The Minister for Primary Industries and Water has now approved that the two areas will remain closed until 2018 (inclusive).
The large rock lobster being released into the Research Areas are specially marked with one or more of the following: two separate holes of at least 5 mm in diameter in the tail fan, two coloured lines on the underside of the tail or a blue T-bar tag with the words "TAFI Research illegal To Take".
In the two areas, there is no fishing by diving or use of rock lobster pots or rings. Also, it is an offence to be in possession of these specially-marked research rock lobster (see photos).
Visit the UTAS School of Zoology
urchin research homepage for the latest information on the project.