The Great Barrier Reef By Ashleigh Cocking & Stephanie McQuinn
Introduction The Great Barrier Reef is the world’s largest coral reef system. The Reef is composed of about 3,000 individual reefs and 900 islands. The Great Barrier Reef is located in the Coral Sea, off the coast of Queensland, Australia. Most of the reef is protected by the ‘Great Barrier Reef’ marine park. The Great Barrier Reef can be seen from out of space and sometimes referred to as the single largest organism in the world. The reef was also selected as a world heritage site in 1981, & been labelled one of the seven natural wonders of theworld.
Coral Reefs About 500 million years ago the first coral reefs occurred, and about 230 million years ago the first relatives close relatives of modern corals developed in Southern Europe, so compared to southern Europe the Great Barrier Reef is only a kid being only 500,000 years old. There’s over 400 hundreds different types of this brilliant coloured coral. Sadly, there are huge threats to coral, the biggest threats are human activity, pollution and over- fishing.
During 1998 until 2004 Coral Bleaching was a huge problem, sea surface temperatures rose above normal. Many tropical coral reefs were bleached or killed. Recovery has been noted, but only happens on rare occasions. Where Reefs occur? Fringing reefs - can be found on the continental islands that were once a part of the mainlands. Ribbon or outer reefs - grow on the edge of the continental shelf. Platform or patch reefs - support a cay, or island formed by sedimentary remains swept onto the reef . Where Reefs occur? Fringing reefs- Ribbon or outer reefs- Platform or patch reefs-
Dangers on the Reef On the Reef, there is a lot of dangerous animals, some of the main animals you should keep clear of are the Irukandji Jellyfish, blue ringed octopus, lion fish, stone fish, sea snakes and stingrays. Irukandji Jellyfish are found in the deeper water, even though they get swept to the shore, they are a threat to snorkellers and scuba divers. Box Jellyfish are found around river mouths and muddy shallow water, they are on of the most dangerous on the reef. They get their names from the shape of their bodies Blue ringed octopus are only the size of a golf ball, when it glows electric blue it means been provoked and is doing it in defence, although it may look pretty and harmless, it can kill you in only a few minutes.
Lion fish belongs to the scorpion fish family. They have a very venomous fin spine that can produce painful puncture wounds. Each species has a pattern of zebra like strips. Stone fish The stone fish is a brown- greenish colour which allows them to camouflage against the rocks. They have 13 dorsal spines that release a poisonous toxin when touched. It mainly lives in the coral reefs near the rocks, and can also be found in the mud or sand
Sea Snakes have small fangs and are not normally aggressive. There are 15 different species of sea snakes on the reef. There are no reported deaths on sea snakes but is still a threat to humans. Stingrays- are not usually aggressive, they have barbs on the tail and fling up when they are trodden on and can leave deep wounds. They eat on little creatures like small fish, molluscs and worms.
Tourism The Great Barrier Reef is a very popular destination for tourists, especially for scuba divers. Many cities along the Queensland coast offer boat trips to the reef on a daily basis. Many of the surrounding islands have been turned into resorts. It has been estimated in 2003 that the tourism in the Great Barrier Reef generates over 4 billion annually. The are approximately two million visitors to the Great Barrier Reef every year.
Warming The most common cause of bleaching is abnormally high ocean temperatures. Bleached coral isn’t always dead coral as it normally regains it colour when it’s surroundings go back to normal, If it stays bleached for a long time then it may be dead.
10 Questions • How many millions years ago did the first coral reefs occur. • The Great Barrier Reef is largest single what? • How many different types of coral are there in the Great Barrier Reef? • What’s a ribbon reef? • Name 3 dangers on the Reef • How many tourists have been estimated to visit the Reef every year? • If coral is bleached, does that mean its dead? • What is the size of a golf ball, Glows electric blue and can kill you in a few minutes. • The Great Barrier Reef is made out of 3000 reefs and how many islands? • Is it a world heritage site??