The Great Barrier Reef

The Great Barrier Reef

The Great Barrier Reef is a long chain of Coral Reef in the middle of

the Coral Sea of the Coast of Northern Australia. It is the largest

deposit of Coral in the world and extends from about 2,010 Km from

point MacKay Queens land to the Torres Strait, between Australia and

New Guinea.

A shallow lagoon or channel separates the reef from the Australian

Coast. The Channel varies in width from 16 Km at its narrowest to

240Km.

The reef protects the Channel form Harsh winds and waves from the

Coral Sea therefore making the waters calm.

Island and ringlets are scattered across the Choral Reeef. These are

often referred to as Atolls or Cays, which range in size up to 300000

square Kilometeres.

And make ship navigation especially difficult. Te Atolls are home to

billions of different species of animals, which include

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- Varieties of dolphins and whales,

-Dugong and green turtles,

- More than 1500 species of fish

-200 species of bird life

-4000 types of mollusc

and many many more.

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The Reef itself is made up of billions of tiny skeletons or polyps

-which are tiny, live creatures, which join together to form colonies.

Each polyp is a tiny jelly-like blob crowned by tentacles, and looks

not unlike an anemone, but much smaller. Each polyp lives inside a

shell of aragonite, a type of calcium carbonate, which is the hard

shell we recognise as coral. The polyps join together to create

forests of coloured coral in interesting fan, antler, and brain and

plate shapes.

There are many different types of coral, some are slow growing and

live to be hundreds of years old, others are faster growing. Algae

create the colours of coral. Only live coral is coloured. Dead coral

is white.

A major threat towards the reef is herds of starfish (Crown of

Thorns), which feed on the Coral and eventually destroy parts of the