The rocky coastal shoreline is a realm of constant change. As the tide rises and recedes, seawater fills gaps between the rocks, creating unique worlds teeming with diverse marine creatures who compete for resources. This area is divided into three distinct zones, each with its own set of challenges and inhabitants.

High Intertidal Zone:

This zone is only covered by water for a few hours each day during high tide, leaving the organisms that live here exposed to harsh conditions including intense sunlight, drastic temperature changes and a relentless battering of waves.

Middle Intertidal Zone:

This intertidal zone experiences twice-daily tidal cycles, alternately submerged and exposed. The creatures that live here have adapted to constant changes in temperature, oxygen levels and moisture.

Low Intertidal Zone:

This area is the classic tide pool most people picture. It is almost always underwater, except during the lowest of spring tides. The sheltered environment creates the perfect habitat for a variety of sea life.


Zones: High

Using barnacle cement, these thrill-seeking crustaceans securely attach themselves to nearly any surface underwater. The special cement doesn’t only lock them in place but also helps them maintain moisture as the tide goes out.

Sea Star
Zones: Low

Equipped with tiny tube feet, sea stars suction themselves to the slick rocks of tide pools. The ochre sea star can tolerate eight hours of air exposure during low tides, a length of time that would dry out any other species of sea star.

Sea Urchins
Zones: Low & Middle

During low tide you can find these spiky creatures doing their part to keep the ocean healthy by grazing on algae.

Zones: Low & Middle

These inactive carnivores wait for the tide to bring them dinner when it washes in plankton and small fish.

Hermit Crabs
Zones: Middle & High

These resourceful crabs find and occupy empty shells made by other animals like the marine snails. As the tide recedes, they can be seen scurrying to small crevices for shelter.

Zones: Low

All 10 species of the blue-ring octopus reside in tide pools throughout Asia and Australia. In North America, the young two-spot octopus can be found in low intertidal zones ranging from central California to Baja California, Mexico.

Sea Slugs
Zones: Low

A variety of sea slugs call tide pools home. Despite being slow moving, even the most brightly and flamboyantly colored species can be hard to spot since many are less than an inch long.

Have fun! Exploring tide pools is a great way to learn about marine life and to experience the beauty of nature.

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