Reef-Building Corals

Reef-Building Corals• Coral reefs are produced by millions of

coral polyps, each removing calcium and carbonate from sea water and depositing it as a hard skeleton.

Reef-Building Corals

• As one generation of polyps reproduces, the new polyps build their skeleton on the foundation of the old.

Reef-Building Corals

• This cycle has resulted in the build-up of coral into huge reefs -- and some have actually become islands over time (for example, the Florida Keys).

Reef-Building Corals

• All reef-building corals possess algae within their tissues. The algae photosynthesize, utilizing the waste products of the coral (carbon dioxide, nitrogen, and phosphorus).

Coral Bleaching

Reef-Building Corals

• In turn, the coral use the food and oxygen produced by the algae during photosynthesis. Without the algae, the corals would not have the ability to secrete the massive stony skeleton we call the reef.

Reef-Building Corals

• Since the algae need light for photosynthesis, reef-building corals grow only in ocean water less than 300 feet deep. The corals need warm water (above 70°F) and do not tolerate low salinity or murky water.

Reef-Building Corals

• The only place in the continental United States suitable for coral reef formation is around the Florida Keys, where there is warm, clear water from the Gulf Stream.

Coral Reefs

What coral reefs do for us:

• Provide shelter for marine life• Provide humans with recreation• Potential source of medicines• Create sand for beaches• Buffer shorelines from storms; coastal

protection• Fisheries, sea food

What we do to coral reefs:

• Coastal development; deforestation• Disease• Overfishing & destructive fishing• Pollution from agriculture• Sewage• Global warming

NOAA Research

Reef Revival

Coral Reefs

• Extremely diverse.

• Multiple species live within coral reefs.

• https://www.youtube.com/watch?v=wbNeIn3vVKM

• https://www.youtube.com/watch?v=ctqvqES1PE8