Barnacles are crustaceans that have jointed legs and shells of connected overlapping plates. Instead of crawling after food, they glue themselves to rocks, ships, pillings, abalones, and maybe even whales and wait for food to wash by. When barnacles are under water or when a wave washes over them, they reach out little feathery barbed legs to strain out plankton and absorb oxygen.

A barnacle's fertilized eggs hatch into larva, then they leave the parents' shells. They spend their youth swimming. After many molts they settle down to adulthood, held permanently by one of the strongest known natural adhesives.

The barnacle's enemies are worms, snails, sea stars, fish like sheephead, certain shorebirds, and oil spills. Some are parasites inside crabs or in other animals.

Diet	plankton
Size	2-5cm wide up to 2 cm high
Color	white, dirty pink, brownish, and a greyish-green neck
Life Cycle	egg, larva, leaves parent's shells, spends youth swimming, sticks to rocks for all adulthood.
Predators	worms, snails, sea stars, fish like sheephead, certain shorebirds, oil spills
Neat Facts	catches food with feathery barbed legs
Types	Acorn barnacle, Brown Buckshot barnicle, Thatched barnacle, and Goose barnacle
Relatives	shrimp, crabs, lobster, copepods, amphipods