Ningaloo Coral Reef

• Category: Marine and Oceanic Biomes.
• Geographic Location: Australia.
• Summary: Famous for the mass spawning events of coral organisms, Ningaloo is among the best-developed fringing coral reefs anywhere and the only major reef on the west coast of any continent.

Located offshore of the state of Western Australia, Ningaloo Reef is the only major coral reef on the west coast of any continent. It extends for more than 186 miles (300 kilometers) parallel to the coast in the Gascoyne region. Considered perhaps the best-developed fringing reef in the world, the Ningaloo is the site of one of nature’s most spectacular mating rituals.

After the March full moon at neap tide, when tidal motion is at a minimum between 8:00 a.m. and 10:00 p.m., the corals spawn simultaneously in the still waters. Wind-driven waves later wash the larvae out to sea. Sometimes, however, the waves do not appear on schedule. The growing coral larvae deplete the oxygen in the lagoon, leading to asphyxiation of the larvae, fish, and even the parent corals themselves. Since its discovery in 1989 at Ningaloo, this accidental mass-death phenomenon has been observed at other reefs.

While the landscape onshore of the reef is arid, occasional summer tropical storms can cause flooding, as happened in December 2010, when some areas received more than 9 inches (22 centimeters) of rain. Coastal areas from Shark Bay southward receive additional moisture in the form of winter rains, which support a more savanna-like vegetation and spring wildflower displays.

Biota

South of the Ningaloo Reef, the vegetation is dominated by eucalyptus trees, while the northern, more desert-like areas are dominated by acacia shrubs. This area was not always a desert. Until 3 million years ago, northwestern Australia was covered with rainforest. At this time, the Indonesian archipelago rose from the ocean floor, changing ocean currents and blocking warm water traveling south along the Australian coast. This led to the decline of precipitation in Australia, and was the death blow to rainforest vegetation.

Ningaloo Reef supports 200 species of coral, 500 species of fish, 600 species of mollusks, and 90 species of echinoderms. There are large populations of dugongs, marine turtles, whales, and whale sharks. The dugong, a large aquatic marine mammal, is found feeding on seagrass beds around sandy lagoons. Among the fish, whale sharks are especially attracted to the coral spawning.

Two offshore currents, one south-flowing (Leeuwin Current) and one north-flowing (Ningaloo Current), interact in the area of the reef, enhancing biological growth and reproduction, and attracting whale sharks, manta rays, humpback whales, sea snakes, large predatory fish, and seabirds.

Cape Range National Park has a limestone karst landscape, supporting 500 caves and sinkholes with rare subterranean aquatic fauna. These animals have evolved in isolation as the Australian continent separated from Gondwana and became increasingly arid as it moved north. Part of the Ningaloo World Heritage Area, the Cape Range karst area formed when seawater dissolved limestone rocks. The aquatic community of the Bundera sinkhole here is unique in the Southern Hemisphere for its remipede crustaceans. Rock wallabies, kangaroos, emus, echidnas, and lizards are common animals.

Offshore, in deeper water, the Cape Range Canyons support upwellings that help maintain the biological diversity of the Ningaloo Reef system. Early peoples used the Cape Range area for the exploitation of marine resources, with records dating back at least 32,000 years.

Protected Areas

Ningaloo Reef is protected by Ningaloo Marine Park. Together with adjacent properties at Cape Range National Park and Muiron Islands Marine Reserve, this area has been named a World Heritage Site.

Also part of the World Heritage Site is the Muiron Islands Marine Management Area. These islands are a northward extension of the Cape Range, and contain important turtle nesting areas used by loggerhead turtles, an endangered species preyed upon by golden ghost crabs. The limestone reef at Muiron Islands contains thousands of cardinalfish. In addition to Ningaloo Marine Park, Cape Range National Park, and Muiron Islands, the World Heritage Site includes Bundegi Coastal Park on Exmouth Peninsula, Jurabi Coastal Park on Exmouth Peninsula, and Learmonth Air Weapons Range; these are all in the Gascoyne region.

To the south of Ningaloo is Shark Bay, another World Heritage Site. Constituent units of the Shark Bay site include Dirk Hartog Island National Park, Francois Peron National Park, Hamelin Pool, and the Bernier and Dorre Island Nature Reserve. The bay itself is a marine park that supports vast assemblages of dugongs, sharks, turtles, and whales. The world’s largest seagrass beds are here. The entire Shark Bay-Ningaloo area is designated as an Australian National Landscape for conservation and tourism purposes.

North of Ningaloo Reef, Montebello Islands Marine Park, Lowendal Islands Nature Reserve, and Great Sandy Islands Nature Reserve were the site of British nuclear tests in 1952 and 1956. These parks protect about 300 islands with mangroves, corals, tropical fish, and seabirds. A whale migration path also passes by the islands. The Lowendal Islands are an Important Bird Area for the crested tern and bridled tern. The Montebello Islands are an important bird area for the fairy tern, roseate tern, and sooty oystercatcher.

Environmental Threats

Environmental issues in the area include the management of commercial fishing, the potential for oil drilling around the Muiron Islands, the management of ecotourism effects on the reef, and the impacts of climate change, including ocean acidification, warm-water-driven coral bleaching events, more frequent and intense cyclones, and rising sea levels.

In 2018, the federal government of Australia, under Prime Minister Malcolm Turnbull of the Liberal Party, increased the total area of the nation's marine parks that were open to commercial fishing from 63 percent to 80 percent. Ningaloo Marine Park, which includes Ningaloo Reef, was affected, as are waters near the Great Barrier Reef. Critics, including conservation groups and scientists such as the Ocean Science Council of Australia, have decried it as effectively removing those habitats from protection and was “inconsistent with the Australian government’s commitment to evidence-based marine management.” Among the opponents is mining magnate Andrew Forrest, who announced in July 2018 that he was donating $100 million to the conservation of marine parks via his Minderoo Foundation.

Exmouth Gulf serves as a nursery for many of Ningaloo Reef's marine species, and is therefore critically important to the reef's health and sustainability. In December 2021, after much discussion and opposition to proposed development in the area, the Government of Western Australia announced protection for Exmouth Gulf and began developing plans for a new marine park over the eastern and southern parts of the gulf. It allocated $3.4 million in the 2022-2023 state budget to planning and protecting the area.

In 2023, the Great Barrier Reef Foundation worked with a network of experts from across the world to create the first Resilience Strategy for any World Heritage Marine Site. The strategy is a coordinated effort between communities, First Nations Peoples, governments, and reef conservation organizations that aims to help limit the impact of climate change on the reef and the surrounding area. Experts quantified the reef’s economic contribution to the community to help inform policymakers, created a framework for research and reef restoration efforts with consideration of sacred sites of the First Nations Peoples, community activities, and tourism operations, and established a plan for better education about the environment and the reefs. These efforts are critical for preserving the region's ecosystem, as some research indicates the Ningaloo Reef area is more vulnerable to severe damage caused by climate change than the Great Barrier Reef.

Bibliography

"About the Ningaloo Reef." Ningaloo Discovery, www.ningaloodiscovery.com.au/about-the-ningaloo-reef. Accessed 2 Dec. 2024.

Bates, Alistair. "Shark Bay and Ningaloo Reefs Face Increased Climate Change Danger, Scientist Warns." ABCNews, 23 July 2024, www.abc.net.au/news/2024-07-23/shark-bay-ningaloo-reefs-in-great-danger-scientist-warns/104122576. Accessed 2 Dec. 2024.

“Coral Sea Marine Park Management Plan 2018.” Federal Register of Legislation, Australian Government, 2018, www.legislation.gov.au/Details/F2018L00327. Accessed 2 Dec. 2024.

"Environmental Scoping Document: Learmonth Bundle Site." Environmental Protection Authority, Government of Western Australia, 18 Apr. 2018, www.epa.wa.gov.au/sites/default/files/Environmental‗scoping‗document/CMS17231-Final%20Approved%20ESD-180418.pdf. Accessed 2 Dec. 2024.

Hashem, Nicole. “Government Winds Back Marine Protections to Support Fishing Industry.” The Sydney Morning Herald, 20 Mar. 2018, www.smh.com.au/politics/federal/government-winds-back-marine-protections-to-support-fishing-industry-20180320-p4z5at.html. Accessed 2 Dec. 2024.

Kurmelovs, Royce. "Exmouth Gulf: Development Plans Stir Up Fears about Future of Ningaloo's Neighbour." The Guardian, 25 Sept. 2021, www.theguardian.com/australia-news/2021/sep/25/exmouth-gulf-development-plans-stir-up-fears-about-future-of-ningaloos-neighbour. Accessed 2 Dec. 2024.

O’Shea, Ben. “Mining Magnate Andrew Forrest Commits $100 Million to Ocean Conservation as Minderoo Foundation Takes to the Seas.” The West Australian, 31 July 2018, thewest.com.au/news/andrew-forrest/mining-magnate-andrew-forrest-commits-100-million-to-ocean-conservation-as-minderoo-foundation-takes-to-the-seas-ng-b88911719z. Accessed 2 Dec. 2024.

"Resilient Reefs Ningaloo." Government of Western Australia, www.dbca.wa.gov.au/management/world-heritage-areas/resilient-reefs-ningaloo. Accessed 2 Dec. 2024.

"Significant Progress for Environmental Protection of Exmouth Gulf." Government of Western Australia, 16 May 2022, www.wa.gov.au/government/media-statements/McGowan-Labor-Government/Significant-progress-for-environmental-protection-of-Exmouth-Gulf-20220516. Accessed 2 Dec. 2024.