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intertidal zone


The intertidal zone ecosytem is generally broken down into 4 areas.

  1. The Spray Zone (or Supratidal Zone -- above the tide zone): This zone is high up on the beach above where even the high tide reaches. But it does get sprayed by big waves and flooded during storms and unusually high tides. Not much wildlife or plant life survives here. It is like a desert.
  2. The High Tide Zone (or Upper Mid-littoral Zone): This zone is underwater only when the tide is high. It is a very salty area, as small pools left when the tide goes out evaporate, leaving the salt to collect.
  3. The Middle Tide Zone (or Lower Mid-littoral Zone): This zone spends half its time under water and half its time in the open air. This zone gets the fiercest wave action. This is where you start to see seaweed.
  4. The Low Tide Zone (or Lower Littoral Zone): This zone is mostly underwater. It gets dry only for a short time during low tide. There is tons of wildlife in this zone.