Coral+Reefs

=Coral Reefs=

General Information:
Coral reef is a kind of under water environment, formed by limestone formations. Reef limestone consists largely of a framework of skeletons from ocean animals called corals. Reefs also include the dead bodies of other limestone-making organisms, such as algae and shellfish, as well as sand and other particles. A coral reef is a complex, biologically rich ecosystem- that is, a community for living things and their environment. Many of the world's most beautiful animals live in coral reefs.**1** The coral is a shelter to many living creatures making it a complex habitat. The habitat includes all different kinds of fish, sponges, Blacktip Reef Sharks, eels, jellyfish, anemones, sea stars, crabs, shrimp, lobsters, turtles, sea snakes, snails, octopuses, nautilus and skeletons making the base of coral reefs.**2** Anatomy of a coral polyp**{6}**

Coral Reef History:
The coral reefs that exist today have been forclams. There are two types of coral, hard and soft. Hard corals have hard limestone ming since the last of the 3 perods in the Pleistocene, Glacial period. The seawater that was frozen into ice, caused sea level to fall. When that happened, all of the reefs before that died from being out in the air. However, when the glaciers began to melt, sea level rose to what it is today, and the existing reefs started to form. **3**

Fringing Reefs:
The Fringing reefs are most commonly found in the shorelines of continents and the islands in tropical seas.Most are in the South Pacific islands in Hawaii, and in some parts of the Carribean. Fringe reefs are closest to shore. They are between 150 to 1500 feet from shore. Fringe reefs are mostly found around developing islands. Young fringe reefs are called apron reefs. One can find Fringe reefs near the Hawaiian Islands. They need warm water (72 - 80 degrees F) and can survive in fairly rough water.**5** A map of coral reefs in the World**{6}**

The Great Barrier Reefs:
The Barrier reefs are deeper than that of the fringing reef. These are formed when some land sinks, and Fringing reefs are then torn apart. They are sepparated by large channels. The land sinks when Crustal Plates move, causing land to get higher or lower. These are more commonly found in the Indo-Pacific. The biggest Barrier reef in the world is off the coast of Australia, and it is called The Great Barrier Reef. It is so large that it spans 1,240 miles wide!{7} This is a picture of an Atoll coral**{7}**

Atoll Reefs:
The Atoll reefs are formed like the Barrier reef, only the land mass is a small island. An island will sometimes sink into the water, and it becomes and Atoll reef. These reefs are also reefs that surround a central lagoon. These also are mostly in the Indo-Pacific. Kwajalein is the largest Atoll reef, and surrounds a lagoon that is over 60 miles long.**{6}**

Coral Reefs in Danger:

 * A huge reason why coral reefs are in danger is because of human fishing. It is estimated that about 60% of the World's reefs are at risk due to human’s destructive activities. In Southeast Asia a ton of reefs are in endangered, about 80%. Since many reefs are in danger, people have been trying to set up national parks, wild life refuges around Asia to try and save the reefs.** **(6)**