A strategy is being developed following the National Centrostephanus Workshop that aims to both control the species in Tasmania and optimise its value as a premium product
While nibbling on urchin ‘popcorn’ or dumplings and butter, participants at the recent National Centrostephanus Workshop in Tasmania had the chance to reflect on how a challenging environmental situation is poised to become a more positive climate change story.
A Welcome to Country Ceremony
Dr Patrick Hone and Senator Peter Whish-Wilson
Sea Urchin popcorn
Via the workshop, a plan is in place to develop a national strategy to deal with both the challenges and opportunities that the Longspined Sea Urchin – Centrostephanus rodgersii, or Centro for short – might bring.
In the 1970s when Centro began its move from its native NSW towards south and eastern Tasmania on the back of warming waters, the situation seemed like a daunting environmental catastrophe, says Fisheries Research and Development Corporation (FRDC) Tasmania Extension Officer David Maynard.
“On the face of it, it has seemed like a catastrophic event. Centro denuded reefs of macroalgae, created moonscapes, and reduced habitat for abalone and lobsters and non-commercial species,” says David.
Positive outlook
“But by flipping the narrative, this challenge can become a success. It can be tackled head-on and produce environmental, social, cultural and economic benefits.”
David says Centro roe is already considered a high-value export product. “Don’t think of this as a pest species. Instead, it is an overabundant, valuable resource that has benefitted from the warming climate. Within that construct, we need to protect marine habitats and other high-value species like the Southern Rock Lobster and Abalone species.”
Like any complex issue, there is a range of solutions and all point to management, says David who is both a research scientist and a keen recreational fisher.
“Eradication is not a realistic objective because larvae are delivered from NSW to Tasmania on ocean currents. We have to accept that Centro is something that is with us to stay.
“What we can do is decide where we want a sustainable commercial fishery and where we want to minimise its presence by total removal by fishers or culling. Recreational fishers will have a part to play in identifying urchin outbreaks, and possibly culling.”
Likewise, aquaculture is also an option with representatives from Japan’s Kita Sanriku Factory telling participants that Centro roe (known as Uni) is a premium product in the global market.
The two-day workshop in Launceston was co-sponsored by FRDC and the Tasmanian Department of Natural Resources and Environment and supported by the state’s Abalone Industry Reinvestment Fund. The 130 participants from across Australia were provided with an update on Centro’s biology and ecology, its impacts on the marine environment, and the many management options available. “This put everyone on the same page, dispelling a few myths, confirming fisher observations and detailing cutting-edge fisheries management theory,” says David.
Robotics, machine learning and data
Workshop participants heard how robotics, machine learning and associated data collection could all play a part in managing Centro.
Dr Christopher Izzo, FRDC Senior Research Portfolio Manager
David highlights the use of robotics on the Great Barrier Reef to help control the Crown of Thorns Starfish. “Similarly, underwater remotely operated vehicles can be used to cull urchins, particularly in depths below 30 metres, the maximum depth that divers can work to.”
David Maynard, FRDC Extension Officer TAS
Robots could also be used in harvesting. “Machine learning will allow autonomous vehicles to differentiate Centro from other urchin species and collect urchins instead of culling,” he says.
Data collected by commercial divers could also help with management. “This data isn’t currently available to urchin divers, but it is recognised that access to data would bring efficiencies to targeting Centro, making it easier and less costly to harvest.”
In the same manner, data from mapping the seabed could also assist population controls.
Peter King, from AMC Search’s Autonomous Maritime Systems Laboratory, spoke about the latest capability in this area. Peter says a combination of high-resolution underwater imagery, sonar and laser could be used to accurately map urchin barrens, and even identify individual urchins.
David points out that machine learning advances would allow Centro to be differentiated from non-target urchins.
“This sounds a bit space age, but all the technology and methodology exist today, and over the next decade the tech will become cheaper, making it a cost-effective control method.”
Next steps for a national strategy
A Task Force supported by the three fisheries agencies for New South Wales, Victoria and Tasmania, along with CSIRO and FRDC will progress a proposal to the Commonwealth Government to develop a national coordinated Longspined Sea Urchin strategy and suggested funding by June 2023. This will also involve grass-roots fishers, processors, recreational divers and researchers meeting to take more immediate R&D opportunities further.
Researchers are already working on kelp regeneration projects, and the processing sector is investigating how they can value add to urchin waste by turning it into valuable fertiliser for the agricultural sector.
FRDC will continue to support R&D in the area as it has done in the past through diverse projects that have looked at options from commercial Centro harvesting to safe-guarding reef-dependent fisheries.
David likens the industry’s coordinated approach to a game of golf. “You can’t play your best game of golf with just one club. Similarly, there is not just one response to Centrostephanus. Instead, the workshop identified a range of responses, and these will be applied in different ways and times, and in different locations.”
This relates to R&D Plan Outcomes 1, 2, 3, and 5
