01 — The national picture
Most Australians grow up beside it without ever knowing its name. Below the surface of the southern coast lies a vast, interconnected forest of kelp — and over the past two decades, large stretches of it have quietly vanished. Ocean rewilding in Australia is the work of bringing those forests back.
A kelp coastline most Australians never see
Australia is wrapped by the Great Southern Reef, an interconnected temperate kelp system that runs for thousands of kilometres — from Western Australia, around the south coast and Tasmania, and up into New South Wales. It is not a single reef but a continuous green belt of seaweed forest that underpins major abalone and rock-lobster fisheries and supports an exceptionally high share of species found nowhere else on Earth. For all that, it remains one of the country's least-known natural assets.
That asset is under pressure. Ocean warming, recurring marine heatwaves and spreading sea-urchin barrens are stripping kelp from reefs faster than it can regrow. In places the canopy has all but gone, leaving bare rock where a living forest once stood. Kelp restoration in Australia has become a national-scale challenge — and the case for rewilding Australia's coastline has never been more urgent.
The crisis looks different in every state
There is no single story of kelp loss in Australia. The drivers vary along the coast, which is why a national response has to be assembled state by state. Each stretch of the Great Southern Reef carries its own distinct threat — and its own route back.
- Western Australia — heat-driven loss: a severe marine heatwave in 2011 pushed water temperatures far above normal and wiped out kelp across the northern edge of WA's range, much of it never recovering. Kelp restoration in Western Australia →
- Tasmania — the urchin frontline: a strengthening East Australian Current has carried the long-spined sea urchin south, and giant-kelp forests off the east coast have collapsed into barrens. Kelp restoration in Tasmania →
- New South Wales — where the urchins came from: the long-spined urchin's home range, with patchy barrens along the coast and warming water pushing the problem ever southward. Kelp restoration in New South Wales →
- Victoria — barrens on the doorstep: urchin barrens are appearing on reefs close to one of the country's largest coastal populations, putting accessible kelp forests at risk. Kelp restoration in Victoria →
- South Australia — cool-water scale: the state's cooler, expansive reefs hold some of the largest temperate kelp systems in the country, making the scale of both the asset and the task immense. Kelp restoration in South Australia →
- Heat
- Marine heatwaves, like WA's in 2011, can erase kelp from a coastline in a single season.
- Urchins
- Warming water carries grazing urchins south into Tasmania, NSW and Victoria, locking reefs bare.
- Scale
- South Australia's vast cool-water reefs make the rewilding task enormous — and the prize just as large.
Where we work
Ocean Greens is focused on five priority states strung along the Great Southern Reef. The plan is to start on the reef itself and rewild state by state — clearing barrens, rebuilding kelp, and funding the next stretch with self-supporting seaweed farms. Each state page sets out the local picture and how the model adapts to it:
- Tasmania: the front line of the urchin barren crisis, where giant kelp has collapsed off the east coast.
- Victoria: barrens emerging within reach of a major coastal population and accessible dive reefs.
- New South Wales: the long-spined urchin's home range, and the source of its southward march.
- South Australia: vast, cool-water reefs holding some of the nation's largest kelp systems.
- Western Australia: a coastline scarred by the 2011 marine heatwave and slow to recover.
Rewilding is the where; the how is a method in its own right. If you want the detail on clearing urchins, replanting native kelp and the science behind it, see our kelp forest restoration page rather than this geographic overview. The forests we rebuild also draw down carbon as they grow — the basis of our work on blue carbon in Australia.
Our national plan, in phases
Scaling ocean rewilding across a continent is a staged effort, not a single event. Ocean Greens frames its work as a sequence of plans and targets — each building on the last, and each funded in part by the seaweed the farms produce:
- Now → 2027 — scale on the Great Southern Reef: prove and grow the model on the reef, building the seaweed-farm engine that pays for expansion.
- 2027 → 2030 — rewild priority barrens nationwide: clear and replant priority barrens across the five states, working toward a 5,000-hectare target by 2030 (a stated target, not a result achieved to date).
- 2030 onward — extend the model globally: take the self-funding rewilding approach beyond Australia, where temperate reefs face the same pressures.
Common questions
What is ocean rewilding?
Helping a degraded marine ecosystem recover the species and structure it has lost. For Australia's temperate reefs that mostly means bringing kelp back — clearing urchin barrens and re-establishing kelp forests so the wider web of marine life can return.
What is the Great Southern Reef?
The interconnected system of temperate kelp reefs that wraps the southern half of Australia, from Western Australia around to New South Wales. It spans thousands of kilometres, underpins major fisheries, and supports a high share of species found nowhere else.
Which states does Ocean Greens work in?
Five priority states along the Great Southern Reef: Tasmania, Victoria, New South Wales, South Australia and Western Australia. The plan is to start on the reef and rewild state by state.
How is the kelp crisis different in each state?
Western Australia was hit by a 2011 marine heatwave; Tasmania, NSW and Victoria face spreading urchin barrens as warming water carries the long-spined urchin south; South Australia's challenge is the sheer scale of its cool-water reefs. Ocean Greens tailors its approach to each.