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Coral Reefs 101

Dec 27, 2006

Coral reefs are one of the most ecologically important organisms in the world - but they're dying at an alarming rate. Find out more about these amazing ecosystems and what you can do to save them!

What are Coral Reefs?

Coral reefs may look like stone but they are actually made up of tiny clear organisms called coral polyps and their skeletons. They develop in shallow, warm water, usually near land, and mostly in the tropics - between 70 and 85 degrees fahrenheit (21 - 30 celsius). They are home to one-third of all marine fish species and thousands of other species. Reefs provide homes to fish, support endangered and threatened species, and are safe havens to marine mammals and turtles. Without coral reefs to call home, these animals could all die.

Threats to the Reef

More than half the world's coral reefs are threatened by humans, either through coastal development, over-fishing, and/or marine pollution. One of the greatest threats is elevated seawater temperatures, which result in "reef bleaching." Reef bleaching occurs when water temperatures increase (due to global warming), which causes algae - the major food source of coral polyps - to die. If there are no algae, there's no coral and if there is no coral, thousands of marine species could become extinct.

Types of Coral Reefs

  • Fringing reefs: Reefs that form along a coastline and grow on the continental shelf in shallow water.
  • Barrier reefs: Reefs that grow parallel to shorelines but farther out than fringing reefs. They are usually separated from the land by a deep lagoon.
  • Coral Atolls: Rings of coral that grow on top of sunken volcanoes in the ocean. They start off as fringe reefs surrounding a volcanic island and then - once the volcano sinks - only the reef remains.

What You Can Do to Save the Reef

  • Encourage your 'rents not to use chemically enhanced pesticides or fertilizers. They leach into the groundwater and ultimately end up damaging coral reefs.
  • Support reef friendly businesses. Ask how reef-friendly your tour company is if you go diving on your next vacation.
  • Tell your peeps how important the reef is so that they can help support the cause.
  • Recycle. Manufacturing plastic, and metal from scratch can lead to global warming so help out by recycling your trash.
  • Before buying tropical fish, ask if they were ecologically harvested. Some fish are caught in a manner that damages the reef.
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