The Great Barrier Reef

The Great Barrier Reef

The Great Barrier Reef was viewed as a labyrinth by early explorers rather than as a natural wonder of the globe. Before it was charted in the 1800s, the aggregation of more than 3,000 reefs and 600 islands off the northeast coast of Australia led to numerous shipwrecks. Lieutenant James Cook's collision with the reef in 1770 was the first official "discovery" of it. The reef has caused many shipwrecks, which continue to be well-liked diving sites for the millions of tourists that explore the reef's waters each year, despite Cook's crew's quick-thinking ability to repair the ship and continue sailing.

The Great Barrier Reef, which stretches 1,250 miles from north to south, is frequently referred to as the world's biggest living thing. It is not, however, a single live organism in the strictest sense. The Great Barrier Reef and other coral reefs are composed of hundreds of microscopic coral polyps that stack one on top of the other and adhere to one another via coralline algae. More than 400 different coral species may be found on the Great Barrier Reef, which is 10 times more than can be found in the entire Atlantic Ocean. More than just an abundance of coral may be found in this underwater paradise. More types of life can be found on a single coral wall than there are on a whole continent.

The reef is home to 1,500 different species of fish, and more are discovered every year. The majority of scientists concur that the Great Barrier Reef is just 500,000 years old on average, despite the possibility that some parts of it may be 2 million years old. According to the coral reef, that is young. Since then, variations in sea level brought on by the ice ages have repeatedly halted its growth. The current reef's structure, which is between 6,000 and 8,000 years old, was developed on top of earlier reefs that were created when sea levels were higher. Learn about the many island and reef types that make up the Great Barrier Reef in this article. One who resides there What dangers do they face? How does Australia manage each square mile of it? You'll learn about the islands and reefs that make up this marine paradise.

Despite being dubbed the "Great Barrier Reef" and frequently just "the reef," both names are inaccurate. Although the ecosystem is made up of many separate reefs, only some of which are true barrier reefs, the names imply the existence of a single barrier reef. The remaining reefs are a mix of platform, patch, fringing, and barrier reefs. Uncertain of which is which? We'll let you know.

  • A vast, deep lagoon divides the ocean from the land, and barrier reefs grow along the continental shelf's furthest borders (a continent's underwater boundary). At their shallowest points, they occasionally break the water's surface as they echo the coastline.
  • Barrier reefs and fringed reefs both parallel coastlines, although fringed reefs are closer to the shore. They are only separated from land by a small, shallow lagoon and border islands or spread away from the continent.
  • Platform and patch reefs are two types of small, solitary reefs that develop on top of the continental shelf, frequently on submerged hills that offer an ideal surface for coral growth. Platform reefs typically have an oval shape and can range in length from 1.9 to 6.2 miles. Platform reefs are larger and deeper than patch reefs.
  • Long, thin reefs called "ribbon reefs" form along the continental shelf's edge. This reefs don't have a lagoon. However, they are just 1,640 feet broad and can stretch up to 16 miles long.

The Great Barrier Reef's terrain alters as it moves south, as seen if you were to fly above it. The Far Northern, Cairns/Central, and Mackay/Capricorn sectors of the reef are frequently considered to be its three main divisions. Due to its isolation and proximity to the equator, the northernmost part is regarded as having the most diversity. Ribbon reefs are dominant in this area. Their windward sides divert powerful waves and currents, creating a tranquil interior with sporadic patch and surrounding reefs. You would get closer to the center part as the aircraft flew south. The continental shelf would widen and the reefs would be located farther from the land.

Patch reefs and tiny coral islands are found in the broad, shallow area that the larger shelf creates. The most accessible and popular with tourists is this area. In the southern region, the shelf keeps getting wider before becoming narrower and bringing the reefs back up to the surface. The undersea environment is dotted with several patch and submerged platform reefs. As the shelf narrows and temperatures fall to levels unfavourable for coral growth, you would gradually watch the reefs disappear if you continued further south. Low-lying coral or sand islands known as cays are dispersed throughout the more than 3,000 reefs.

Depending on the amount of rainfall they receive, these cays sustain a variety of plant species, including mangrove, rainforest, and grassland. The islands are created when hard algae, shells, and coral sand accumulate on the tops and margins of the reefs. This arrangement benefits both the reefs and the cays. By protecting them from choppy waters, barrier reefs allow mangroves and inner sea grass beds to flourish. By catching nutrients and silt in runoff, these formations stop pollutants from entering the delicate ecology and suffocating the coral. Many of the inhabitants of the reef use them as a nursery. Next, you'll encounter some of those intriguing locals.

Flora And Fauna

More people than just the 2 million visitors every year benefit from the Great Barrier Reef's tropical location. Coral can thrive best in shallow, clear, warm seas that receive plenty of sunlight. Additionally, you can expect there will be a lot of different marine species where there is a lot of healthy coral. More animal species can be found on reefs than in any other marine ecosystem. In addition to the 1,500 fish species stated previously, the reef is home to more than 200 bird species, 4,000 different mollusc species, 30 different whale and dolphin species, and six different species of sea turtles.

Researchers discovered 1,441 sea worms from 103 distinct species and 250 different types of shrimp on just one piece of coral. One of the rare sites where you might encounter an overstuffed gigantic grouper, a whale shark larger than your car, and a dwarf goby fish smaller than your fingernail all in one dive is the Great Barrier Reef. Species that are "non-fish" are just as beautiful. Giant clams can grow up to 4 feet long and weigh more than 440 pounds. Their rainbow-colored mantles are as distinctive as fingerprints.

While you should give the Great Barrier Reef's animals some room, you might want to give some of them, such the 20 species of sea snakes, a wider berth because some of their venom is 20 times more potent than that of the most toxic land snake. The tiny blue-ringed octopus is another creature to be aware of. This dangerous mollusk, which measures barely five to twenty centimeters, has startled hungry divers who try to smuggle shells into their wetsuits only to get bitten by the venomous octopus hiding inside. Coral is a powerful substance as well. You'll get a scorching itch after even a light brush with the stinging fire coral.

Another aquatic animal is deadly, but not to humans, only to the reef. Since the early 1960s, the crown-of-thorns starfish, which feeds on coral, has wreaked havoc on the reef twice. A path of devastation is left in their wake when thousands of these starfish invade reefs during an outbreak and feast on the weak polyps. The ensuing coral graveyard is frequently colonized by algae, which delays the coral's ability to quickly recover. One of the biggest starfish in the ocean, the crown of thorns, can damage reefs, and it can take up to ten years for them to recover. The unexpected eruptions of the sea stars are still a mystery to scientists, who speculate that everything from runoff to overfishing could be to blame. Despite the harm inflicted by starfish, the Great Barrier Reef has fared better than other coral reefs; its reefs are among the least threatened in the world. On the following page, you'll learn how the reef has managed to avoid danger.

Great Barrier Reef Marine Park

The Great Barrier Reef saw an increase in visitors after scuba diving was invented in 1943. You can see why Australia proclaimed it a marine park in 1975 when you consider overfishing, limestone mining, and oil drilling. Together, the federal government and the state of Queensland oversee the park's intimidating 132,973 square miles. The reef is guarded by the Great Barrier Reef Marine Park Authority. The park is the biggest marine protected area in the world even though it excludes the reef's northernmost portion. The park includes a number of marine habitats in addition to the reef, such as mangroves, estuaries, seagrass beds, and deep ocean troughs.

Officials separated the maritime park into distinct zones when it was established, outlining what activities were permitted and prohibited there. The many types of zones varied from general usage zones, where most activities including fishing, swimming, and boating were allowed, to scientific research zones, which were only accessible to the scientists doing the research. The Australian government made the decision to reevaluate the configuration of the marine park in light of reports of animal populations dropping in the reef and global warming.

At least 20 percent of each habitat type has been designated a "no-take" zone, and the marine park has now been divided into 70 different habitat types. No-take areas, as the name implies, ban activities like shell collection and fishing because nothing may be taken from them. Less than 5% of the park's area was no-take protected prior to the evaluation. Currently, this method of protection covers 33% of the park.

The marine park attracts more than just tourists. Its abundant marine life and relatively virgin reefs are excellent for scientific study, according to researchers. For instance, researchers from the Australian Institute of Marine Science have even identified the protective layer that coral exposed to air secretes, and they are collaborating with a pharmaceutical business to use this information to create sunscreen. It would take a lifetime to explore all of the Great Barrier Reef's reefs and cays, but that doesn't stop people from trying.