More than 70% of the Shark Bay World Heritage Area is marine, and many of the features that underpin its World Heritage status lie beneath the water. Shallow, mostly sheltered bays support the world’s largest seagrass meadows, ancient stromatolites, and a population of more than 10,000 dugongs. These ecosystems are among the most productive and scientifically important marine environments on Earth.
The Shark Bay Marine Park (748,725 hectares) and the Hamelin Pool Marine Nature Reserve (132,000 hectares) were established to protect these natural values while allowing for recreation such as boating and fishing. A zoning system balances conservation with use, ensuring sensitive habitats like seagrass banks and stromatolite reefs are preserved for future generations.
Dugong Research
Shark Bay supports more than 10,000 dugongs (Dugong dugon), around 10% of the global population of this vulnerable species. Long-term research has focused on dugong breeding, foraging behaviour, and interactions with predators such as tiger sharks, providing critical insights into how this species uses the Shark Bay environment.
Tagging and tracking studies show that dugongs avoid water temperatures below 18°C and migrate seasonally, moving from shallow inner gulfs in summer to deeper, warmer waters in winter. This research, carried out in collaboration with local Indigenous groups, complements traditional ecological knowledge from the Malgana and Nhanda peoples and directly informs conservation management of dugongs and their seagrass habitats.
Turtle Monitoring
Shark Bay is home to more than 6,000 marine turtles, including the endangered green turtle (Chelonia mydas) and loggerhead turtle (Caretta caretta). One of the most significant projects is the long-term monitoring of loggerhead turtle nesting, with Shark Bay recognised as one of Australia’s most important nesting areas.
Since 1994, researchers and volunteers have monitored nesting activity at Turtle Bay on Dirk Hartog Island, tagging and measuring turtles after egg-laying. These long-term studies are essential because turtles take more than 30 years to mature and may live for over a century. The findings help scientists understand population trends, migration, and breeding success, supporting better long-term conservation decisions for these species.
Seagrass
Shark Bay contains the largest seagrass meadows on Earth, covering about 4,000 square kilometres of seabed. Twelve of the world’s 60 seagrass species occur here, thriving in the bay’s shallow, sheltered and low-energy waters.
These meadows underpin Shark Bay’s marine ecosystems, supporting fish, turtles and one of the world’s largest dugong populations. Different seagrass species dominate different habitats, with some forming dense stands and others providing key seasonal food sources for marine animals.
Seagrass Restoration
Following an unprecedented marine heatwave in 2011, large areas of Shark Bay’s seagrass meadows were lost, impacting habitats, wildlife and ecosystem resilience. In response, researchers, Traditional Owners, community volunteers and conservation partners have joined forces to restore damaged seagrass habitats. Using innovative techniques such as seagrass transplantation, biodegradable restoration structures and Indigenous-led Sea Country stewardship, these projects are helping to accelerate natural recovery and develop restoration methods that may benefit coastal ecosystems around the world.