Goose barnacles also called stalked barnacles or gooseneck barnacles, are filter-feeding crustacean

Crustacean

Crustaceans form a very large group of arthropods, usually treated as a subphylum, which includes such familiar animals as crabs, lobsters, crayfish, shrimp, krill and barnacles. The 50,000 described species range in size from Stygotantulus stocki at , to the Japanese spider crab with a leg span...

s that live attached to hard surfaces of rocks and flotsam in the ocean intertidal zone

Intertidal zone

The intertidal zone is the area that is above water at low tide and under water at high tide . This area can include many different types of habitats, with many types of animals like starfish, sea urchins, and some species of coral...

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Some species of goose barnacles are pelagic and are most frequently found on tidewrack on oceanic coasts. Unlike most other types of barnacles, intertidal goose barnacles depend on water motion rather than the movement of their cirri for feeding, and are therefore found only on exposed or moderately exposed coasts.

In Portugal and Spain, they are a widely consumed and expensive delicacy known as percebes.