MacKerricher State Park Intertidal Studies

Observe the rocky shore at low tide and you will notice the distinct horizontal color bands on the rocks. One of the obvious features noticed by students visiting the coast is that intertidal organisms tend to occur at certain levels or zones. These bands show that organisms are not randomly distributed, but tend to occupy distinct and predictable zones within the intertidal. The intertidal zone can be divided into four biologically recognizable zones; the spray zone, the high-tide zone, the broad mid-tide zone, and the low-tide zone. While intertidal zonation occurs in both sandy beach and rocky environments, it is most observable in rocky environments.

The Splash Zone

High-tide Zone

The Mid-Tide Zone

The Low Tide Zone