Page 187 - Hawaii: Diving, Surfing, Pearl Harbor, Volcanoes and More

The Mid Reef: Nature’s Wonder

he Mid Reef or alternately referred to as Platform reefs range from small clumps of coral
Tplatform 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
in platform like reefs. With further radial growth, orals reproduce both sexually and asexually.
lagoonal platform reefs develop. The shape of an CAn individual polyp uses both reproductive
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.