Page 61 - French Polynesia
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The Mid Reef: Nature’s Wonder

The Mid Reef or alternately referred to as           Platform reefs range from small clumps of coral
     platform reef is characterized by a primar-     to huge, sprawling reefs. They are widespread

ily radial growth pattern. A platform reef may       throughout the coastal zone of Meso-American

or may not lie behind a barrier reef and may         Barrier Reef and numerous Caribbean islands.

undergo elongation if established on a sand-         The Mid Reef is found in deeper waters than the

bank. These reefs reside in 30 to 50 feet of         patch reefs of near-shore environments at depths

water and are home to massive sea life and a         20-60 feet. Bank reefs are significantly larger than

wide biosphere. These reefs begin by growing patch reefs and are common dive and snorkel

towards the surface of the ocean, eventually         destinations and have high species diversity,

spreading out sideways. Reefs grow actively          meaning many kinds of animals and plants live

outward as well as upward, especially in the         on and around this type of reef. Bank reefs have

stable conditions of a continental shelf. Any        something special called spur and groove pat-

given reef, having depth and temperature fixed terns. The spur and groove formation is made up

by its location, will have its shape determined      of low ridges of corals (spurs) separated by sandy

by the direction and force of the water currents bottom channels (grooves). The most commonly

that bring food and by the shape of the base on found corals are elkhorn, staghorn, seafans, sea

which it grows. Where the forces of growth are whips and brain corals.

equal in all directions, radial expansion results    Corals reproduce both sexually and asexually.
in platform like reefs. With further radial growth,        An individual polyp uses both reproductive
lagoonal platform reefs develop. The shape of an

elongated platform reef may be determined by modes within its lifetime. Corals reproduce sexu-

the orientation of rising and falling tidal currents. ally by either internal or external fertilization.
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