Notes Coral Reef Characteristics Coral reefs are massive

Notes: Coral Reef

Ø Characteristics Coral reefs are massive biological communities and geologic structures. Ø Made of Calcium carbonate Ø Corals – small sessile cnidarians that live as polyps Ø • • • eat zooplankton (night) common nervous and digestive system colony begins with one polyp that clones itself.

Anatomy of Coral

Zooxanthellae and Coralline Red Algae Ø Corals contain symbiotic zooxanthellae photosynthetic algae that live within the coral. l l help coral deposit Ca. CO 3 faster provide food through photosynthesis (day). Ø Coralline red algae – grow in rock hard sheets on the surface of the reef l l Protect it from wave action Trap sediments

Location of Coral Reefs Ø mainly in shallow, warm water near the equator Ø around continental shelves Ø around islands Ø top of seamounts

Threats to Coral Global warming is killing coral – heat stress causing coral to die/bleaching-turn white. Ø Divers walking on coral Ø Crown of Thorn Starfish Ø Partial bleaching

3 types of Coral Reefs Ø Fringing Reef –narrow platforms a short distance from shore and don't contain a substantial lagoon. Example: Red Sea Reef – dry climate.

3 types of Coral Reefs Ø Barrier Reef – farther from shore than fringing reef. Example: Great Barrier Reef – Australia.

3 types of Coral Reefs Ø Atoll – a reef that forms around a sunken seamount, usually far from land. Circular shaped with a lagoon in the middle.

What type of reef are these?