Hiking Where The Tide Pools
To understand what goes on beneath the sea, find a rocky shoreline and explore away
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Sure, the Olympic Coast beach I’m hiking is beautiful, in a superficial way. Waves wash over soft sand, erasing my partner’s tracks even as she makes them. So why is it that I won’t pitch camp here and instead am so eager to reach the rocky point ahead? Because sandy beaches bore me. They chatter day and night with nothing much to say. Put stone beneath my feet, though, and twice daily I’ll watch the sea pull back and reveal its wondrous secrets.
Below high tide on rocky shores you’ll find an encyclopedia of creatures. Even more hospitable are those rare places where pools of sea water remain as the tide sinks lower. These wild aquariums can be full of exotic riches. Fantastically colored sea slugs, called nudibranchs, glide among swaying fronds of many-hued algae. Tiny fish dart their manic missions. Brilliantly colored, upside-down sea stars move deliberately and almost imperceptibly across overhanging boulders.
My first guide to these alien worlds was my mother, Dr. Marilyn Harlin, now a marine biology professor at the University of Rhode Island. “Tide pools make you live in the present,” she says by way of partially explaining her love of exploring them. “Because they’re exposed so briefly, you have to observe them on their own terms. In return, you get to visit environments you’d otherwise have to wear scuba gear to witness.”
Tides, of course, lie at the heart of tide-pooling, and not all tides are equal. During full and new moons, the ocean’s highs become higher, its lows, lower. These are “spring” tides (no relation to the season), and their lows often expose tide pools you won’t see at any other time of the month. As a general rule, the Pacific’s tides, at 10 to 20 feet, are much greater than tides on the Atlantic coast, providing a larger area for discovering tide pools. Still, any rocky shoreline-New England, for example-is prime tide-pooling territory.
East or West, as a coastal explorer you want the lowest tides you can get. This is because the upper tidal zone-the one that takes the heaviest brunt of sun, wind, heat, cold, and waves-provides the least nurturing environment.
On rocks that become exposed early during the dropping tide, species diversity is relatively low and animals tend toward the crusty side. Barnacles, for example, add traction to slippery rocks, but don’t make for exciting spectating.
Drop down a few feet, to places that are exposed daily only at low tides, and the creatures get a bit showier. Mussels stick to the rocks by extruding filaments stronger than steel. In turn, beds of mussels create an environment in which small sea stars and other mobile creatures can live.
At the next level down, the lowest tides of the month expose rocks usually submerged to reveal spiny beds of colorful sea urchins that have carved round nooks into the rock so they can survive the force of waves.
At the lowest level of a tidal zone, a tide pool kidnaps a piece of the receding sea, and the diversity and showiness of animal and plant life explodes. Especially fruitful are shadier, more sheltered nooks. Here multicolored sea anemones “bloom.” These creatures “open” to look like green or purple flowers a few inches high and wide, but are actually carnivorous animals. Touch one and it quickly pulls inside itself. If your finger were a small fish, the anemone’s clinging stingers would paralyze it, and then draw it toward a gaping mouth. (Even though your finger won’t feel the sting, be gentle with your probing, and keep in mind that no creature welcomes a finger jammed down its throat.)
Should the tide pool drain or become too warm, the anemone will curl up into a tight water-conserving and wholly unexciting blob. Look in crevices and under big boulders for clusters of brightly colored sea stars, anemones, and spiny urchins.
As a rule of thumb, it’s okay to pick up a sea star or other animal if gentle, constant pressure causes it to release its grasp, but if you have to pry, take the hint and leave it alone. After a brief look, put everything back the way you found it. Replace rocks, tuck snails back under the seaweed, return sea stars to their rocky perches. Move gently and gradually.
According to Bob Steelquist, education coordinator at the Olympic Coast National Marine Sanctuary in Port Angeles, Washington, and a guest on Anyplace Wild’s Olympic Coast episode (check your local PBS listings this summer), after dark is the most memorable time to explore an already fascinating world.
“There’s something about focusing all your attention on a strange and somewhat threatening environment lit by the single beam of a headlamp. You do need to be careful, but you are rewarded by seeing fishes and other species that won’t come out in the daylight.” What might attract backpackers to poke around among ocean rocks after dark? “Without any lights to seaward,” says Steelquist, “night tide-pooling puts you on the edge of the ultimate wilderness, the dark ocean itself.”
If you’re a coastal hiker, chances are that high-mileage days aren’t your focus anyway. And if you find yourself along a rocky coast and you see that the receding tide has left behind
glittering pools of water, forget “forward” progress. Drop your pack above the high-tide line and spend a few hours poking around the seaweed. You won’t be bored, I promise.
Leave No Trace
- Return any overtuned object to its original position. Something may be living on or under every surface.
- Do not remove any animals or plants, or harvest shellfish for eating, without the land manager’s approval.
- Return animals to protected locations under seaweed or rocks, according to where you found them.
- If an animal or plant clings fast, leave it alone.
- Don’t crush animals by walking on them. (Most barnacles recolonize quickly; these colonies can withstand limited foot traffic.)
- Soft-bodied animals, including some sea stars, will tear easily when picked up, so don’t.
Better safe than soaked
- Wet rocks are slippery, and seemingly bare rocks may be covered with a thin algal film. Be extremely cautious on steep terrain.
- Wear neoprene dive booties for better traction and to protect feet and ankles from scrapes (they won’t help against sea urchin spines).
- Don’t turn your back on the sea-rogue waves can sneak up on you. A rising tide quickly brings waves within striking distance and can leave you stranded if you aren’t paying attention.
- If a wave takes you by surprise, hold tight to a rock until you can scramble higher.
- Check with guidebooks or locals about currents and hazards.
- Explore with partners and stay in continuous verbal contact; watch out for each other.
- Rock crevices provide safer footing, but beware of sea urchins. Remove the spines promptly or dissolve them with a mild acid, such as vinegar or lemon juice or, in a pinch, urine.
- Avoid the surf zone when seas are exceptionally rough.
- Beware of logs carried by waves or lying loose on the rocks.
- Don’t eat mussels unless you’re certain they are free of toxins.
- Don’t touch jellyfish. Some sting.