Great Barrier Reef Fast Facts: Mind Boggling Diversity

The Great Barrier Reef (GBR) is the largest reef structure and marine park in the world and to think it all started with a single coral polyp – no bigger than a grain of rice - attaching itself to a rock under water. Wind, weather and waves have combined to shape the reef into one of the world's last great wilderness areas.

  • Biologically speaking, the Great Barrier Reef is the most diverse eco system in the world and collectively there are more corals here than anywhere else on the planet.The extraordinary biodiversity and interconnectedness of species and habitats also make the Great Barrier Reef and surrounding areas one of the most complex natural systems on Earth. Collectively, there are around 70 broad scale habitats (called bioregions); 30 reef bioregions and 40 non-reefal bioregions.
  • Coral Reefs comprise around seven per cent of the Great Barrier Reef World Heritage-listed area. The rest is made up of seagrass (6000 square kilometres), mangroves (2000 square kilometres representing 54 per cent of the world's mangrove diversity), sand, algal and sponge gardens and inter-reefal communities as well as deep oceanic areas more than 250km offshore.
  • No less than 14 coastal eco systems are vital to the survival of the reef. These include coral reefs, lagoon floor, islands, open-water, seagrasses, coastline, estuaries, freshwater wetlands, forested floodplain, heath and shrub lands, grass and sedge lands, woodlands, forests and rainforests.

The diversity continues...

  • Birds, seabirds and shorebirds: The islands and cays along the Great Barrier Reef support breeding populations of some 22 seabird species and 32 shorebird species. Areas of international significance for migratory and resident species of shorebirds are also found on, or adjacent, to the Great Barrier Reef.
  • Bryzoans (or moss animals - tiny colonial organisms): Around 950 species of these tiny animals (they form coral-like colonies and are often confused with coral) have been recorded on the reef.
  • Crustaceans: Around 1300 crustacean species, including a number that are commercially important (e.g., some species of crabs and prawns) make their home on the reef.
  • Echinoderms: Echinoderms are known for their radical symmetry with starfish being a prime example. You'll find around 630 species recorded along the Great Barrier Reef.
  • Fish: Look out for 1625 species of bony fish - including important commercial species such as coral trout – on the reef.
  • Hard corals: This is the signature group found on the Great Barrier Reef, with more than 450 species known.
  • Jellyfish: More than 100 species of jellyfish are recorded along the Great Barrier Reef, including blue bottles and box jellyfish.
  • Marine mammals (whales, dolphins, dugong and seals): More than 30 species of marine mammals are found along the Great Barrier Reef. Bottlenose dolphins, humpback and dwarf minke whales are frequently seen, whilst other species such as Bryde's whales are seldom seen orrecognised. The Great Barrier Reef is also an important habitat for dugong.
  • Marine turtles: Six of the world's seven species of marine turtle are found on the Great Barrier Reef with globally significant nesting areas for four of these found in region. All six species are classified as 'threatened'. A fully grown leatherback turtle can reach a length of 2 metres and weigh up to 900kg. At the other end of the scale, olive ridley turtles are the smallest of the marine turtles.
  • Molluscs: This group includes clams, oysters, squid, octopus, cuttlefish, nautilus, nudibranchs, chitons and snails - with than 3000 species known on the Great Barrier Reef.
  • Sea anemones: Around 40 species have been recorded along the Great Barrier Reef.
  • Sea snakes: Sitting in a global hotspot of sea snake diversity, the Great Barrier Reef is home to 14 breeding species of sea snake, which is primarily due to the Marine Park's variety of suitable habitat. Whilst most species of sea snake have extremely powerful venom, they prefer not to waste it on humans.
    Sea squirts (sometimes called Ascidians): Around 720 species provide a splash of colour on the reef.
  • Soft corals and sea pens (this critters are so named as they look like old fashioned pen quills): At least 150 species are known to live on the Great Barrier Reef. This equates to roughly 10 per cent of the world's soft coral.
  • Sponges: Around 30 per cent of Australia's sponge species are found in the Great Barrier Reef.
  • Worms: Around 20 known species of marine insects and five known species of marine spiders are found in and on the reef, although Scientists think this number is likely to be greater. The cultural diversity is equally impressive.

DID YOU KNOW more than 70 Aboriginal and Torres Strait Islander clan groups / sea country people are connected to the reef? Please contact the PR team and ask for the full diversity fact sheet.

Word Count: 785
Author: Tourism and Events Queensland

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