A Tasmanian program paid commercial divers to harvest invasive long-spined sea urchins, helping kelp forests recover on the state's east coast. The cost was about A$0.40 per urchin, far cheaper than comparable reef management, and local kelp showed measurable regrowth. Australia's federal government has now declined to continue funding the program, despite a Senate inquiry and peer-reviewed studies backing its effectiveness. Kelp forests along the Great Southern Reef store a significant share of Australia's blue carbon, and their decline has hurt the abalone fishery. The program's design used a commercial market for urchin roe to offset removal costs, but the economics pushed divers toward already-barren areas rather than zones where prevention would work. Without targeted subsidies, scientists warn that restored kelp areas could revert to urchin barrens and carbon storage gains will be lost.
