MARE 194

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MARE 194

• Types of Coral Reefs

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Why Different Kinds of Reefs?

• Apron Reefs?100 yrs old (off Big Island)
• Fringing Reefs?100-1000 yrs old (Kawaihae)
• Barrier Reef?5-7 million yrs old (Kauai)
• Atoll?11.7 million yrs old (French Frigate Shoals)

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Flashback !
As islands move away from hotspot
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Darwin Point

Kure Atoll, aka. Darwin Point
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Reef Community vs Coral Reef

• Reef Community
• Coral Reef

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Youngsters Apron Reefs

• Juvenile Fringing Reefs

• Big Island almost all reefs are coral
  communities or apron reefs, especially along Kona
  Coast
• Puako

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Fringing Reefs
Reef Crest ?est wave energy
Reef Slope most coral here
Reef Flat ?est coral diversity
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Fringing Reef
In HI, many reefs are adjacent to the shoreline
high human impact!
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Barrier Reef

• ridge of coral 

Fore Reef
Back Reef
Barrier vs fringing reefs?
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Barrier Reef
Two barrier reefs in HI Kaneohe Bay, Oahu
Mana Reef, Kauai
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Hawaiian Barrier Reef
Kaneohe Bay, Oahu
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Atoll
Cay or Motu
More coral diversity, less coralline algae
More massive corals due to ? wave energy
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Coral Atoll Formation
In HI Many atolls exist in NW island chain
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Darwins Hypothesis on Atoll Formation
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Pacific Atolls
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Northwest Hawaiian Islands Become National
Monument!

• June 15, 2006
• Starts near Nihoa
• First monument to be controlled by Dept of
  Commerce (and not Dept of Interior)

Papahanaumokuakea Papahanaumoku is the goddess
who birthed the islands. Her husband was Wakea.