An Irvine tradition: Summertime at Crystal Cove

by Jenny Rigby

Crystal Cove’s shoreline is home to a dazzling array of plants and animals. Their presence is defined by the rhythm of the tides. Twice each day, the tides rise and fall, covering and then exposing the rocks. Each time the tide recedes, it leaves pools of seawater brimming with sea life.

These tidepools are protected as a State Marine Conservation Area. Visitors are welcome to gently explore them, but need to leave everything, including animals, algae, rocks and empty shells, in place.

Life in a tidepool is determined by tolerance of exposure to the drying effects of the sun and wind. Acorn barnacles, limpets, periwinkle snails and other animals that live in the highest reaches of the splash zone are left high and dry for hours at a time.

Animals that live in the high tide zone, including California mussel, sea stars and sea urchins, have to endure the impact and drag of a pounding surf. They anchor their bodies to the rocks in various ways, including threads of glue, tube feet and suction cups.

Animals that live in the low tide zone, such as the reclusive two-spotted octopus, giant keyhole limpet and California spiny lobster, are visible at very low tides.

 

Tips and notes

There are four tidepool viewing areas in Crystal Cove State Park: Reef Point, Rocky Bight, Pelican Point and Treasure Cove. Each location is a short hike from the parking area of Crystal Cove State Park. The tidepools are most accessible at low tide. Check the tidal chart before you visit. Stay safe when out in the surf, keep your eye on the ocean and wear sandals or shoes with grip.

Jenny Rigby directs The Acorn Group, a design firm dedicated to interpreting natural history.


 

CALIFORNIA SPINY LOBSTER- Limp and empty, a molted lobster exoskeleton looks like the ghost of a lobster. The real animal is long gone, hiding somewhere as its new and larger suit of armor begins to grow.
PURPLE SEA URCHIN- This animal grazes on algae in the tidepools. It relies on its spines for protection and for trapping food. Purple sea urchins tend to cluster together, resembling small purple porcupines.
HERMIT CRABS- Lacking a hard shell, a hermit crab seeks safe housing in an empty shell. If you approach a black turban snail and it moves away quickly, chances are that the shell is occupied by a hermit crab. Photo: Kent Treptow.
BLACK TURBAN SNAIL- Black turban snails cluster on tidepool rocks. They move slowly, using their suction-powered “foot” to slide across the surface. They graze on algae, shredding it with their sandpaper-like rasp. Photo: Kent Treptow.
LINED SHORE CRAB- As long as its gills stay wet, a shore crab can cruise around dry, exposed rocks. Try sneaking up on one. Their eyes move on stalks and can detect even the slightest movement from all sides.
GIANT GREEN ANEMONE- At low tide, anemones look like round blobs covered with bits of shell. At high tide, they transform into flowerlike animals whose tentacles wave in the water. Paralyzing stinging cells cover them. What you feel as stickiness is a death blow to a tiny fish.