University of New South Wales Sydney
Quantifying the ecosystem services of the Great Southern Reef
The Great Southern Reef is a network of temperate rocky reefs that spans more than 8000 km of the Australian coastline, from Kalbarri in Western Australia to northern New South Wales. It was first described as an ecological entity in 2016 to raise awareness about the immense social, cultural, environmental and economic value of kelp forests.
From an ecological perspective, the Great Southern Reef is remarkable for its high levels of productivity, biodiversity and endemism. The golden kelp forests that dominate the temperate reefs interlink with other coastal habitats including giant kelp forests, seagrass meadows, sandflats, mudflats, saltmarshes, mangrove forests, oyster reefs and sponge gardens. They also connect with deeper habitats along the continental shelf.
A major concern is that kelp forests are rapidly diminishing due to ocean warming, marine heatwaves and pollution. In 2011, 96,300 hectares of kelp forest were lost in Western Australia. Giant kelp forests are listed as Endangered under the Environment Protection and Biodiversity Conservation Act 1999. Warm-affinity species are moving south, transforming reefs and local ecosystems. For example, long-spined sea-urchins have caused the collapse of 15% of reefs in Tasmania and are projected to degrade 50% of reefs by 2030. At the warm edge of their distribution, kelp forests are also threatened by the range expansions and growing populations of tropical herbivorous fishes, which can overgraze kelp or prevent its recovery from marine heatwaves. Human population growth is a further source of pressure.
The Great Southern Reef supports two thirds of the Australian population, yet little research has been done to identify and evaluate the ecosystem services it provides. Accurate estimates of the contribution of kelp forests to society and the economy are needed to support monitoring and evidence-based management. In a global context, quantifying and assessing the benefits of Australia’s kelp forests is relevant to the UN Decade of Ocean Sciences, the UN Sustainable Development Goals, ocean accounting, and guiding efforts linked to the UN Decade on Restoration.
First estimate of Great Southern Reef ecosystem services
This Marine and Coastal Hub project aims to generate a first estimate of the ecosystem services provided by the Great Southern Reef and their economic value. It will compile and synthesise existing data on the ecosystem services provided by shallow rocky reefs dominated by kelp forest habitats along the Great Southern Reef, including market and non-market values. It will estimate the value of these ecosystem services and quantify the benefits they contribute to the five relevant states (Western Australia, South Australia, Tasmania and New South Wales) and to Australia as a whole. Knowledge gaps will also be identified.