THE BIG PINK SEA STAR
Pisaster brevispinus
The low tide days of this time of year may wreak havoc with ferry schedules, but they do reveal to beach visitors a plethora of oft not seen marine creatures.
One I'd not noted before on Cama Beach State Park's mile plus beach on Camano Island was a sea star related to the common purple or ochre star found on rocky shores -- a second Pisaster species -- Pisaster brevispinus.
Why seen on a -- 3.4 day? This star is considered a subtidal species -- usually only seen on the beach on an extremely low tide day, if at all.
And eye-catchers they were at Cama May 18th -- their bright pink color not easily camouflaged among the eelgrass strands. The diameter of one is easily a foot and a half!
Having flabbier rays than the common evasterias (a species that is plentiful on Camano's west shore), this star from deeper waters feeds primarily on the clams which are so numerous in Saratoga Passage between Camano and Whidbey.
When preparing to dine on a clam, Pisaster brevispinus will probably slowly hump itself over the bivalve -- then utilize its many tube feet to exert pressure on the clam-more specifically on the muscles that hold the shells together. As the clam's energy is sapped, it will start to gate open. Voila!
The star, having gained entry, will then undertake a feat perhaps remembered from biology class -- actually slip its stomach into the mollusk. Digestive juices flow -- the tissue softens -- and the star is able to digest the clam -- yes, right in its own shell. Why, the nerve of this fat pink star!
Now it takes longer than overnight to finish this meal -- more like over several nights. But the star does eventually "do da deed" -- and "all in good time" as the saying goes.
Read about still another subtidal seastar, the Sinister Sunflower Star!
Pat Nash
Beach Watcher
Class of '94
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