The Great 8 of the Great Barrier Reef

The “Great Eight” are the iconic creatures of the Great Barrier Reef. While some of the members of the “Great Eight” are seen throughout the Great Barrier Reef year-round, others visit the certain areas at very specific times of the year. Most visitors will be able to meet a number of these magnificent creatures as part of their Great Barrier Reef experience.

1. Whales

  • Up to 10 000 whales make the journey north from the cool waters of Antarctica to the warm, shallow waters of the Great Barrier Reef to breed and have their calves.
  • Whales are renowned for their unique methods of communication. They possess the ability to utilize echo location where they bounce sound waves off objects to determine what and where they are.
  • Humpback whales, dwarfe minke whales, false killer whales, killer whales, short-finned pilot whales, sperm whales and various beaked whales are all species that can be found in the waters of the Great Barrier Reef.
  • The Humpback Whale is the most commonly sighted species of whale on the Great Barrier Reef and can be seen from June and September. .
  • Humpback whales measure around 15 metres in length and can weigh anywhere up to 45 tonnes. They are considered to be giants of the oceans.
  • Humpback whales have an intriguing ability to ‘sing’ underwater. Songs are used to communicate with other humpback whales and some can last for up to 30 minutes.

2. Turtles

  • Sea Turtles have a characteristic large shell called a carapace, four strong flippers and lungs for breathing air. They also have a pointed sharp beak-like mouth used for crushing their food.
  • Sea turtles are known for their ability to travel thousands of kilometres between their nesting locations and feeding sites.
  • Six of the world’s seven sea turtles can be found cruising the waters of the Great Barrier Reef. The most commonly sighted sea turtles of the Great Barrier Reef are green, hawksbill and loggerhead turtles.
  • Female turtles take between 30 and 50 years before they commence breeding. Then they breed every 2 – 8 years.
  • Female sea turtles always return to the same area to nest. Some females found on the Great Barrier Reef are thought to have travelled from places such as Papua New Guinea, Indonesia and New Caledonia.
  • Depending on the species, sea turtles lay between 50 – 100 eggs at a time and during nesting season females may lay multiple clutches.
  • Between January and April, thousands of tiny “hatchlings” can be seen along the shores of Islands and the coastline scurrying from nests in the dunes down into the water where they commence their lives.

3. Sharks

  • Sharks are the top predator of the Great Barrier Reef. They play an important role in ensuring the ecosystem remains healthy by feeding on the sick and injured and controlling those species that have had population explosions.
  • Sharks have multiple rows of teeth for hunting purposes. Unlike many other animals, sharks teeth are constantly being replaced.
  • Different types of sharks reproduce in different ways. Some lay eggs with a tough outer skin while others give birth to live young.
  • There are many different species of sharks found in the waters of the Great Barrier Reef ranging from small bottom-dwelling sharks such as wobbegongs to larger types such as tiger sharks and the distinctive hammerhead shark that has a nose shaped like the letter ‘t’.
  • The most common species of sharks seen on the Great Barrier Reef are white tip or black tip reef sharks. These sharks feed on fish and pose no danger to humans, in fact they are timid and are easily scared.

4. Clownfish

  • There are 1625 species of fish living in the waters of the Great Barrier Reef. The clownfish is just one of these.
  • The clownfish achieved notoriety in the Disney feature film “Finding Nemo” as a playful and active member of the Great Barrier Reef ecosystem.
  • Clownfish are small, striped fish that can be seen the entire length of the Great Barrier Reef swimming amongst the coral known as "anemones". These fish have a unique partnership with coral that sees them live inside its stinging tentacles. This protects them from their predators and, in return the clownfish stops other fish from feasting on the coral.
  • Clownfish are usually seen in family groups inclusive of a male and female pair and their offspring.
  • These colourful fish have the incredible ability to change from male to female. If a female dies, the male will change sex in order to reproduce. Usually the larger clownfish are female.

5. Giant Clams

  • Giant clams are a type of mollusc. A significant proportion of the world’s molluscs call the Great Barrier Reef home.
  • Giant clams have a large, thick and unique shell that they close quickly if threatened by predators, an effective defense mechanism.
  • Interestingly, they have both male and female parts enabling them to produce and fertilise their own eggs.
  • Giant clams are filter-feedings, sucking water into their bodies and filtering food through their gills. Additional nutrients are gained from a symbiotic relationship with a tiny algae called zooxanthellae.
  • Some Giant clams found on the Great Barrier Reef are estimated to be around 120 years old.

6. Rays

  • Rays are closely related to sharks. They both share a skeleton made of cartilage, rough skin and gills exposed on their bodies.
  • Most rays have a flat, disc shaped body. They glide elegantly through the waters of the Great Barrier Reef by waving their pectoral fins.
  • The majority of rays feed on crustaceans and molluscs on the bottom of the ocean. Their mouth is usually located on the underside of their body to facilitate this. Other rays such as manta rays feed on plankton in the water.
  • Rays have a poisonous barb found on their tails that they use only to defend themselves from threats. A human can become sick if struck by this barb.
  • One type of ray found on the Great Barrier Reef is also the world’s largest fish – the Manta Ray. These are massive marine creatures that can grow up to 7 metres wide and weigh up to 1300 kilograms.
  • Manta rays are a blue-grey colour on top and a pale colour underneath. Their eyes are located on the top of the large disc wings and large fleshy feeding flaps that extend from the front of their bodies to guide food into their mouth.
  • Best spotted at "cleaning stations" throughout the Great Barrier Reef, Manta Rays are usually seen at Lady Elliott Island in March and around the Whitsundays and Port Douglas in June and July.

7. Coral

  • The Great Barrier Reef has 411 species of hard coral and over 150 species of soft coral. This equates to 10% of the world’s soft coral.
  • Coral reefs are formed when tiny animals called Coral Polyps extract minerals from the ocean and convert it into hard skeleton homes.
  • When Coral Polyps die the limestone skeleton remains. This forms the building blocks of a coral reef system.
  • Coral cays are formed when coral skeletons, algae and other reef creatures (including shells), sand and rubble are trapped by currents, wind and waves. Over time the environment stabilises and a coral cay is established.
  • About one third of the coral cays on the Great Barrier Reef support some form of vegetation.

8. Maori Wrasse

  • Wrasses are a large and diverse group of fish, the second most abundant found on the Great Barrier Reef.
  • The majority of Wrasses are carnivorous, feasting on invertebrates and other fish. A small number feed on plankton, coral or parasites found on other fish.
  • Most wrasses display different colours at different stages of their life.
  • Maori wrasses are the largest in the wrasse family. They can grow up to 2 metres in length and can weigh up to 180 kilograms.
  • Maori Wrasses are a protected species within the Great Barrier Reef Marine Park.

Want to Learn More?

Find out all the facts about the Great Barrier Reef at the following websites:

Great Barrier Reef Marine Park Authority: The managing body of the Great Barrier Reef Marine Park. There is an abundance of information about the reef and its management at the following website www.gbrmpa.gov.au

Queensland Parks and Wildlife Service: The managing body of Queensland’s national parks. This website has information on the Islands of the Great Barrier Reef that are national parks, including camping, walking and other activity opportunities: www.derm.qld.gov.au

Queensland Holidays: To experience the awe-inspiring wonder of the Great Barrier Reef, book now through the Queensland website: www.Queensland.com

CRC Reef Research Centre: CRC Reef provides research solutions to protect, conserve and restore the world's coral reefs by ensuring industries and management are sustainable and that ecosystem quality is maintained. www.reef.crc.org.au/discover/index.html

 


 


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