Beach at night reveals dark, wet wild surprises

VASHON ISLAND — In the small circle created by our flashlight, an entire world dances. Tiny transparent shrimp kick up a hula, their golden eyes glinting. A red sea cucumber retracts its tutu-like tentacles. Dozens of purple shore crabs scrabble sideways in a herky-jerky line dance.

It's raining and windy, but no one in our group of 20 kids and adults complains — all of us are captivated by the treasure-hunt quality of nighttime beach walking. Repeated exclamations of "come see this!" bounce off the waves as we slowly make our way along an island beach, marveling at a mossy chiton's camouflage and feeling the sticky tentacles of aggregating anemones. Our jacket hoods insulate us from one another, giving the experience a floating, centered quality that reminds me of snorkeling.

Our walk leader, Stephanie Raymond, grew up across the street from Mee Kwa Mooks Beach Park in West Seattle and has been exploring Puget Sound shorelines since she could walk. Education coordinator for People For Puget Sound for the past 15 years, Raymond still uses information gleaned on early beach walks with her parents.

More action at night

Besides the fact that our local winter low tides occur only at night, this is a good time to examine intertidal creatures for several reasons.

"At low tide on a hot summer day these critters are already stressed out," said Raymond. "It's hot and bright and dry, when they prefer cold, dark and wet."

There are also many more predators during daylight hours — gulls and crows feast on any soft-bodied creature they can find, the latter even flipping over rocks in search of a snack.

"Using a flashlight really focuses your attention in one little spot," added Raymond. "In the summer you have a lot more input and it's easier to miss things. At night, when you focus your attention on that little circle of light, you see a lot more detail."

Our spotlights bring out colors and shapes more often associated with tropical beaches, as we touch sponges and whelks, barnacles and mussels — marveling at the strong, hair-like byssal threads that give these bivalves the "muscle" to hold tight to rocks, pilings and each other.

Another benefit to dark-hour exploration is that light-sensitive creatures like octopuses are more likely to be found at night. During years of beach-walking experience, Raymond has found that animals are more likely to venture out of their designated tidal zones at night, making them easier to observe. Crabs, for example, are a lot more active in the dark.

Like sci-fi creatures

We followed a red rock crab for several yards as it worked its way through rocky pools. It finally found what looked like a good hiding place under an overturned clam shell, scuttling backward and burying itself underneath. Raymond lifted up the shell and we were rewarded by a mauve-colored, doughnut-sized sunflower star nestled in the shell's protective curve. This soft-bodied sea star grows up to 24 arms.

Raymond explained that sea stars eat by expelling their stomach into their dinner — be it mussel, clam or oyster. They excrete enzymes to liquidate their meal, then slurp it up before bringing their stomach back "home." Every sea star has "eyes" in the form of small light or dark-colored spots on the tip of each arm. Though they don't see with the clarity we do, they are able to sense light and dark.

Another crab caught our attention: a dinner-sized Dungeness perched still as a statue on a rock. Raymond told us to lift up its back and we cautiously reached out. Like a hinged door, the entire back of the crab opened to reveal a labyrinth of empty chambers inside the body cavity. Raymond explained it was the abandoned shell of a just-molted Dungeness. During the annual molt, an adult crab expands its body by absorbing water, causing its shell to split along the back and sides. The crab then backs out of its old shell and hides for a few days until its vulnerable, soft shell begins to harden — a process that takes about six weeks to complete.

Almost every creature we met had crowd-pleasing, sci-fi qualities, and Raymond's stories kept our group spellbound and bubbling with questions.

Raymond likes to see people build a more personal relationship with Puget Sound by going on beach walks or kayak outings, or working on restoration projects.

"We live near the water and love to spend time around the water," Raymond said. "The shoreline is where people connect with the Sound."

The excited shouts from our group of nighttime explorers showed that they had found their place in the intertidal zone.

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