What Are Tide Pools?
Tide pools are little seawater-filled craters that form by oceans. Often these tide pools are indiscernible during the parts of the day when they are covered with seawater. They separate only at low tide, when they are revealed as microcosmic ecosystems. Naturalists and philosophers alike are fascinated by tide pools because of their scale. As John Steinbeck once wrote, “It is advisable to look from the tide pool to the stars and then back to the tide pool again.” Naturalists are also fascinated by the hardiness of the animals that live within tide pools. These animals must adapt to their environment, which changes daily.
Life in Tide Pools
Tide pool ecosystems are constantly changing. The saltiness, oxygen levels and temperature of the tide pool’s water changes every day. Because of this, only the hardiest organisms, like barnacles, can survive in tide pools. These inhabitants must survive the midday sun, big waves and predators. Tide pool creatures must be able to withstand these changing pressures. Ironically, however, they also rely on the tide pool’s changeability—their greatest danger—to survive. The fresh water provides tide pool inhabitants with fresh food sources.
Tide Pools: Microcosmic Ecosystems
Tide pools form small food chains unto themselves. Starfish eat mussels, which eat plants. Even within themselves, tide pools can be subdivided into smaller regions, or zones.
Tide Pools: The Spray Zone
The spray zone, the area highest up in the tide pool, is constantly bombarded with spray from tides and storms. This part of the tide pool is the most exposed to the elements, like the sun and winds. For this reason, the spray zone is the most difficult area for creatures to survive. It is sparsely populated by only the hardiest creatures, like barnacles, whose impenetrable shells protect them from the elements.
Tide Pools: The High Tide Zone
The high tide zone is the part of the tide pool that is immersed in water only during high tide. While this area is easier to survive than the spray zone, the animals that live within it must still survive an ever-changing environment of waves and sunlight. In the high tide zone one can find crabs, anemones, and mussels. Although waves make life difficult in the high tide zone, they also bring food to its inhabitants.
Tide Pools: The Low Tide Zone
The low tide zone is submerged in water almost all day. This regularizes sunlight exposure and water’s saltiness and provides more shelter for the low tide zone’s dwellers. This easier survival allows for more biodiversity. The low tide zone is populated by more aquatic marine vegetation (seaweeds) than the other zones. Here one can find shrimp and sea cucumbers.