Coral Reef

Coral are limestone formations formed by polyps. They attach to eachother with a sheet of tissue that connects to the middle of another polyps. Polyps take calcium from the sea water to build their limestone skeletons. When the polyps die, they leave the limestone skeletons that become the foundations of barriers and ridges called coral reefs. As new polyps grow, their mass makes the limestone formation larger.

Coral- There are two types of coral, soft and hard. They are the most important species in reefs. Coral is found in reefs and all over seas across the world, mostly in warm waters. Coral settles on a hard support and never moves again, it just reproduces using budding. They are carnivores but they get eatin by crown-of-thorns.
Sponges- Sponges have been in reefs from early on. They appear in a variety of different colors and shapes. 5,000-10,000 different types. They are mostly found in salt water. They mate by hermaphrodites.(each adult can act as either the female or the male in reproduction). They are filter eaters, they eat tiny floating particles. They also provide shelter for shrimp, fish, crab, and other small animals.
Rays- Rays live in all seas across trhe world, many are found in coral reefs. They are flattened fish with no bones. There are 500 different types of Rays. Rays are carnivores, they eat fish, crustaceans, mollusks, and worms. Some rays are oviparous (laying eggs) while others reproduce using aplacental viviparity (giving birth to live young that develop in the womb without a placenta). They mostly live near the sea bed. Rays are known to be very smart.

The coral reefs are known as the rain forests of the sea for many reasons. One reason being because of all the species they harbour. They play an important role as breakwaters, which minimize wave impacts from storms. The beauty of coral reefs makes them a very heavy tourist attraction which helps attract foreign currency and gives many people jobs. There are two types benefits from coral reefs: "Direct Use Values"(fisheries and tourism industry), and "Indirect Use Values" (benefit derived from coastline protection). All in all, coral reefs supply habitat, home to over 1 million species. Income, billions of dollars and millions of jobs in over 100 countries. Food, for people living near coral reefs, especially on small islands. Protection, natural barrier protecting coastal cities, communities, and beaches. And medicine, the potential for treatments for many of the world's most dangerous illnesses and diseases.

Coral bleaching is the whitening of corals, due to stress-induced expulsion or death of symbiotic algae. Under stress, corals expel their zooxantheallae, which leads to a lighter or white apperance. Once bleaching continues, it usually continues even when not under stress. It kills most coral which leads to havey impact on the reef ecosystem, fisheries, tourism, and coastal protection.

Youtube video- http://www.youtube.com/watch?v=lBgh_YmY4lU
Coral Bleaching Pic from.- http://www.global-greenhouse-warming.com/coral-bleaching.html
Info on Coral Reefs Pic from.- http://www.brothersoft.com/coral-reef-3d-screensavers-185850.html
How Coral Reefs Form Pic from.- http://phsadventurers.blogspot.com/
Key Species in Coral Reefs Pic from.- http://www.worldculturepictorial.com/blog/content/most-threatened-species-one-third-world-coral-reefs-on-verge-of-extinction-global-warming-over-fishing
Uses and Benefits Pic from.- http://www.treehugger.com/files/2009/08/hawaii-coral-reefs-fines.php