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During low tide, intertidal creatures (organisms) are exposed to the air. They must not dry out, and they must withstand air temperatures which vary from hot in summer to bitter cold in the winter. Some organisms have adapted to prevent drying out. How do you think they protect themselves to keep from drying out?

Snails withdraw into their shells, and some snails then secrete a mucus seal to protect themselves

Anemones gather in large masses to reduce the body surface area exposed to the air

Purple sea urchins retain water inside their shells (known as a test) during low tide so their internal organs do not dry out

Seaweeds are protected by their vast numbers? The upper layers of seaweed shelter the lower layers so that only a few plants are sacrificed to protect the entire group.

Mussels close their shells tightly to retain water to protect themselves

Waves

Intertidal plants and animals must survive the action of the waves. Intertidal organisms protect themselves from being smashed against rocks or cast up and stranded on beaches in different ways.

Animals such as abalones secure themselves to rocks with their strong muscular feet

Plants such as kelp secure themselves to the ocean floor with their holdfasts

Marine animals hide from the waves by crawling under or between rocks or plants

Crabs and lobsters crawl into crevices in rocks, and small animals hide in kelp

Some algae grow under rock ledges to protect themselves

Some crabs burrow into sand

Molluscs, such as mussels, clams and abalones have shells to protect themselves