Thousands of translucent, worm-like sea cucumbers washed up along Seaside Beach in Oregon this week after a combination of rough surf and low tides pushed them out of their usual habitat, according to the Seaside Aquarium.
Tiffany Boothe, the aquarium’s assistant manager, said the small creatures — known as skin-breathing sea cucumbers — covered more than two miles of shoreline Tuesday.
“They are literally littering the tideline,” she said.
Typically, these sea cucumbers burrow in the sand along the low-tide line or farther offshore.
But when wave conditions and tides line up just right, they can be displaced and end up on the beach — a phenomenon that happens only a few times a year, or sometimes just once every few years.
Each cucumber measures about half an inch long but can grow up to six inches.
Once stranded, they can’t make it back to the water and will eventually dry up and die.
Boothe said the decomposing sea cucumbers will become food for beach hoppers, beach fleas, and other small invertebrates that live along the tideline, though birds tend to avoid them.
The scientific name for the species is Leptosynapta clarki, and they’re found along the Pacific coast from northern California to the Gulf of Alaska.
Boothe said the remains will likely dry up and blend into the sand within a couple of days.
“They’ll probably be gone by Wednesday or Thursday,” she said.
Seaside is about 80 miles northwest of Portland.
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