The Scallops of the Pacific Northwest
Scallops occur all along the pacific northwest coast, Spiny scallops are found sub tidally from 5 to 150 meters in depth, while Pink can be found to a depth of 200 meters. Spiny scallops prefer gravel or rocky bottom. Pink prefer a sand or mud substrate. Both prefer areas with some current. Rock Scallops prefer a very rocky bottom.
Both spiny and pink have distinctive fan shaped shells that are ivory and pink in color, the rock scallop is round and almost invisible with its shell covered in various bits and pieces. they can reach up to 9 cm in size. Minimum size for harvest is 5.5 cm
Harvesting is by dive and trawl, although they are commercially farmed in on the coast as well.
The meat color ranges from ivory to pinkish white and can have a tender yet sometimes chewy texture. It is sweet and moist.
Unlike most bivalves, both pink and spiny types are free swimming. they have a large central abductor muscle that assists in swimming. When faced with danger, they propel themselves away from the danger by clapping their valves together and forcing water out through openings on both sides of their shell hinge. This motion is repeated until the scallop is out of danger.
Pink and spiny types have separate sexes and are mature at 2 years of age.
Spiny scallops spawn from mid August to late October while pink scallops spawn from January to March. The fertilized eggs develop into planktonic larvae that drift for 3 to 4 weeks and are dispersed by water currents before they settle.
They are suspension feeders, feeding mainly on plankton and zooplankton. Predators of these bivalves include sea stars, octopus, snails, fishes, and boring worms.