Great Barrier Reef Marine Life, Reef Facts & Culture.

Migaloo: the world famous white humpback whale.

Migaloo is a regular visitor to the Great Barrier Reef waters in the winter months. The water is to cool for him in the southern Antarctica ocean in winter, so he, and his family and friends migrate up the Queensland coastline to spend their winter holidaying in the beautiful warm waters off northern Queensland.

Most sightings of Migaloo or "White Fella" as the Australian Aboriginals call him are from reef tour boats and fishing vessels on or around the Great Barrier Reef chain.

The Queensland Government has tried to help give this world famous white whale some privacy by enforcing legislation to protect Migaloo. By doing this, he is the only individual mammal in Australia and maybe even the world to have their on personal peace of legislation.

• Vessels can approach Migaloo but NO closer then 500 metres (1640 feet)
  The standard for any other whale is 100 metres (328 feet) and 300 metres (984 feet) for a whale calf.
  
  
• Aircraft can not fly lower then 2000 feet
• With fines for breaching (no pun intended) these laws of $16 500.00

Great Barrier Reef Marine Life

The Great Barrier Reef supports a diversity of life, including many vulnerable or endangered species, some of which may be endemic to the reef system. Thirty species of whales, dolphins, and porpoises have been recorded in the Great Barrier Reef, including the dwarf minke whale, Indo-Pacific humpback dolphin, and the humpback whale. Large populations of dugongs live there.

Six species of sea turtles come to the reef to breed – the green sea turtle, leatherback sea turtle, hawksbill turtle, loggerhead sea turtle, flatback turtle, and the olive ridley. The green sea turtles on the Great Barrier Reef have two genetically distinct populations, one in the northern part of the reef and the other in the southern part. Fifteen species of seagrass in beds attract the dugongs and turtles, and provide a habitat for fish. The most common genera of seagrasses are Halophila and Halodule.

Saltwater crocodiles live in mangrove and salt marshes on the coast near the reef. Nesting has not been reported, and the salt water crocodile population in the Great Barrier Reef World Heritage Area is wide-ranging and with a low population density. Around 125 species of shark, stingray, skates or chimera live on the reef. Close to 5,000 species of mollusc have been recorded on the reef, including the giant clam and various nudibranchs and cone snails. Forty-nine species of pipefish and nine species of seahorse have been recorded. At least seven species of frog can be found on the islands.

215 species of birds (including 22 species of seabirds and 32 species of shorebirds) are attracted to the reef or nest or roost on the islands, including the white-bellied sea eagle and roseate tern. Most nesting sites are on islands in the northern and southern regions of the Great Barrier Reef, with 1.4-1.7 million birds using the sites to breed. The islands of the Great Barrier Reef also support 2,195 known plant species; three of these are endemic. The northern islands have 300-350 plant species which tend to be woody, whereas the southern islands have 200 which tend to be herbaceous; the Whitsunday region is the most diverse, supporting 1,141 species. The plant species are spread by birds.

Seventeen species of sea snake live on the Great Barrier Reef. They take three or four years to reach sexual maturity and are long-lived but with low fertility. They are usually benthic, but the species that live on the soft sediment differ from those that live on the reefs themselves. They live in warm waters up to 50 metres deep and are more common in the southern than in the northern part of the reef. None of the sea snakes found in the Great Barrier Reef World Heritage Area are endemic to the reef, nor are any of them endangered.

More than 1,500 species of fish live on the reef, including the clownfish, red bass, red-throat emperor, and several species of snapper and coral trout. Forty-nine species are known to mass spawn, with eighty-four other species found on the reef spawning elsewhere in their range.

There are at least 330 species of ascidians found on the reef system, ranging in size from 1 mm-10 cm in diameter. Between 300-500 species of bryozoans are found on the reef system.

Four hundred species of corals, both hard corals and soft corals are found on the reef. The majority of these spawn gametes, breeding in mass spawning events that are controlled by the rising sea temperatures of spring and summer, the lunar cycle, and the diurnal cycle. Reefs in the inner Great Barrier Reef spawn during the week after the full moon in October, but the outer reefs spawn in November and December. The common soft corals on the Great Barrier Reef belong to 36 genera.

Five hundred species of marine algae or seaweed live on the reef, including thirteen species of the genus Halimeda, which deposit calcareous mounds up to 100 metres wide, creating mini-ecosystems on their surface which have been compared to rainforest cover.

The most significant threat to the Great Barrier Reef is climate change. Mass coral bleaching events due to rising ocean temperatures occurred in the summers of 1998, 2002 and 2006, and coral bleaching will likely become an annual occurrence. Climate change has implications for other forms of life on the Great Barrier Reef as well - some fish's preferred temperature range lead them to seek new areas to live, thus causing chick mortality in seabirds that prey on the fish. Climate change will also affect the population and available habitat of sea turtles.

Another key threat faced by the Great Barrier Reef is pollution and declining water quality. The rivers of north eastern Australia provide significant pollution of the Reef during tropical flood events with over 90% of this pollution being sourced from farms. Farm run-off is polluted as a result of overgrazing and excessive fertiliser and pesticide use. Due to the range of human uses made of the water catchment area adjacent to the Great Barrier Reef, water quality has declined owing to the sediment and chemical runoff from farming, and to loss of coastal wetlands which are a natural filter. It is thought that the mechanism behind poor water quality affecting the reefs is due to increased light and oxygen competition from algae.tourists, especially in the Cairns, Port Douglas and Whitsundays area. Tourism is also a very important economic factor for all of these areas.

The Great Barrier Reef reaches from Torres Strait, between Bramble Cay, its northern most island and the south coast of Papua New Guinea in the north to the unnamed passage between Lady Elliot Island, it's southern most island and Fraser Island in the south.

The Great Barrier Reef is clearly visible from aircraft flying over Heron Island, a coral cay in the southern Great Barrier Reef. The land that formed the substrate of the current Great Barrier Reef was a coastal plain formed from the eroded sediments of the Great Dividing Range with some larger hills, some of which were themselves remnants of older reefs or volcanoes.

The Reef Research Centre, a Co-operative Research Centre, has found coral deposits that date back half a million years. The Great Barrier Reef Marine Park Authority (GBRMPA) considers the earliest evidence to suggest complete reef structures to have been greater then half a million years ago around (600,000 years ago). According to GBRMPA, the current living reef structure is believed to have begun growing on the older platform about 20,000 years ago. The Australian Institute of Marine Science (AIMS) agrees, which places the beginning of the growth of the current reef at the time of the Last Glacial Maximum. At around that time, the sea level was 120 metres lower than it is today.

From 20,000 years ago until 6,000 years ago, the sea level rose steadily. As it rose, the corals could then grow higher on the hills of the coastal plain. By around 13,000 years ago the sea level was 60 metres lower than todays levels, and corals began to grow around the hills of the coastal plain, which were then islands. As the sea level rose further, most of the islands were submerged. The corals could then overgrow the hills, to form the present cays and reefs. Sea level on the Great Barrier Reef has not risen significantly in the last 6,000 years. The CRC Reef Research Centre estimates the age of the present, living reef structure at 6,000 to 8,000 years old.

The Great Barrier Reef World Heritage Area is divided into 70 bio-regions, 30 are reef bio-regions, and 40 are non-reef bio-regions. In the northern part of the Great Barrier Reef, ribbon reefs and delta reefs have formed structures not found in the rest of the Great Barrier Reef system, There are no atolls in the Great Barrier Reef system, and reefs attached to the mainland are very rare.

For more images check out the image gallery.

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SCULPTURE: Many sculptures have had a reef theme or have been inspired by the sea. The famous mermaids sculpture at the Daydream Island resort is one such sculpture.