Cabrillo Marine Aquarium

Gooseneck Barnacles

Pollicipes polymerus


Fun Facts

    Gooseneck barnacles can live 20 years, or more.

    These barnacles use their feathery feet, called cirri, to both feed and breathe.



  Gooseneck barnacles are filter-feeding crustaceans that live attached to hard surfaces of rocks and flotsam in the intertidal zone. They have a fleshy stalk which attaches to the substrate and many calcareous plates that protect the body and internal organs. As they grow, they make new plates. When first secreted, these plates are shiny and pearlescent. After repeated high tides and battering waves (full of sand and rocks), the pearly shells become scared and dull.
The planktonic larva of this species is unique in that when it settles out of the plankton it crawls around, searching for adults of its own species before attaching to a solid substrate. This explains why solitary gooseneck barnacles are rarely seen; even when there is empty space on the rock, there are always many gooseneck barnacles crowded together in clumps.
To learn more about gooseneck barnacles and their relatives visit the Rocky Shores Room at the Aquarium.