GREAT BARRIER REEFA living wonder. It was World Heritage listed in 1981. The largest complex of coral reefs and islands in the world, consisting of more than 2900 individual reefs and about 900 islands. It runs a distance of 2500km down the coast of Queensland. Its total area is about 344,000 sq.km, the biggest marine park in the world. Its distance from the shore ranges from about 15km to 200km. It has an area larger than the United Kingdom and is longer than the west coast of the USA. It is visible from space.
The Reef contains more than 340 identified varieties of coral, colourful anemones, sea urchins and sea slugs. There are dolphins, turtles, sea snakes, fish, shellfish of all kinds, ranging from great clams to tiny cowries. It is the breeding ground for a number of rare and endangered animals. It is home to the threatened dugong. Humpback whales come on annual pilgrimages from Antarctica during winter. Multitudes of seabirds nest on the islands during spring and summer.
There are not many sharks around the Great Barrier Reef because they prefer the open sea. The ones commonly encountered are the white tip reef, very timid, and black tip reef sharks. They are easily identified by their markings and are often found on the ocean floor. The sharks found on the reef are fish eaters and pose no threat to visitors, unless harassed, when they may attack out of fear.
Coral reefs are colonies of billions of tiny jelly-like individual creatures that have joined together to form colonies which have been built up slowly over thousands of years. Coral is the hard outer skeleton which protects the soft bodies of the tiny animals. There are many hundreds of species and each has a different growth pattern, from mounds, sheets, fans, branches and antlers. Some are fast growing, some slower. Coral feeds mostly on plankton. It is the living coral that gives the reef its colourful appearance. The skeletal coral is white. Shallow warm water is the ideal environment, with lots of water movement, plenty of light, salty water and low in nutrients.
The coral may not appear as colourful as in books or other images. This is due to colours being filtered in the water at different depths. The white lights used in photographing the coral show up the true colours. This makes diving at night so spectacular.
Viewing of the reef is either by snorkelling, scuba diving, semi-submersible vessels, from a glass bottomed boat, or catamaran. There are also scenic helicopter flights.
With more than 2 million people visiting the area annually, tourism may have a negative effect due to human carelessness such as walking on the reefs, anchors dropped and dragged over the coral, pollution from boats and humans, and souveniring. There is support from tour operators, as well as government agencies, to try and preserve the Reef for future generations. Fishing in the area is restricted.
Another big threat is the Crown of Thorns starfish which, since the 1960s has been destroying the corals. Outbreaks of this starfish comes in cycles and has an impact on the reef and also sea and birdlife.
AIR: Cairns Airport, with both international, domestic and general aviation terminals, it
is the ideal base from which to explore the Great Barrier Reef.
Like most tropical climates there are two distinct seasons
The wet season is between November and April.
Average water temperatures range from around 22C in July to around 27C in January.