Celebrate Australia Day with this series of caches and learn some interesting facts along the way.
The Great Barrier Reef is the largest coral reef in the world. It is made up of a collection of over 2,900 individual coral reefs and 600 idyllic islands located between 15 to 150 kilometres off the north-eastern coast of Queensland, Australia in the Coral Sea in the Pacific Ocean. The Great Barrier Reef is 2,300 km (1,450 miles) long. This is about the same distance along the west coast of North America starting at Vancouver and ending in San Diego.
The natural underwater ecosystems built from calcium carbonate structures made from the accumulation of the bodies of billions tiny animals known as coral polyps. In fact, most of the coral structure is made up the calcified remains of dead coral polyps. Only the topmost layers are alive. With the right amount of sunlight, water conditions and temperature, and over long periods of time, corals form the structures the make up the beautiful reefs we see today.
The age of the Great Barrier Reef is about 6,000 to 8,000 years. The original coral reefs started forming in the Pacific Ocean, in the Coral Sea, sometime between 58 and 48 million years ago. There were many reefs formed and then destroyed and reformed over the ensuing millions of years.
The reef is home to a diverse range of underwater creatures. These include:
• 1,625 species of fish
• 360 types of coral
• 450 species of hard coral
• 40 species of sea anemones
• 150 species of soft coral and sea pens
• 3,000 types of molluscs (like giant clams and the sea slug)
• 1,300 species of crustaceans (crabs, prawns)
• 630 species of echinoderm ( starfish, sea urchins)
• 215 species of birds
• 14 species of sea snake
• 6 out of the world's 7 species of sea turtle
• 30 species of cetaceans (whales and dolphins)
• 22 species of sea birds and 32 species of shorebirds
• 30 species of dolphins and whales
• 133 species of sharks and rays
• 100 species of jelly fish (blue bottle, box jellyfish)
• crocodiles
Plants include sea grasses, various types of algae such as seaweed, and Mangroves, which are actually terrestrial plants that grow above the surface of the sea but have their roots in it, are also considered part of the Great Barrier Reef flora.