Crustacean with long, fleshy, flexible stalk permanently attached to hard surface.
Stalk, or neck, ranges from reddish-brown to brownish-black in coloration.
Many hard, pearlescent plates at top, protecting the body and internal organs.
Tiny feathery feet, called cirri, project from plates, and are used to both feed and breathe.
As they grow, they produce more plates.
From southern Alaska to Baja California, Mexico.
Found on rocky cliffs in the splash zone.
Often in high-energy, high wave environments because their fleshy necks can survive it well.
Often in crevices to avoid direct sunlight and limit drying out.
Often in colonies of other gooseneck barnacles.
Also found floating on marine debris in the open ocean.
Gooseneck barnacles reach maturity around age 5.
Although almost all other crustaceans have separate sexes, barnacles are hermaphrodites (each has both male and female organs).
Will only self-fertilize if no other gooseneck barnacle within 8 inches.
Since they are stationary, they have a very long, extendable penis (about seven times as long as their body diameter).
Eggs are brooded in the mantle cavity.
Newborn barnacles extend as one-eyed larvae that feed on plankton and molt several times until they look like miniature shrimp.
When the planktonic larva settles out of the plankton, it crawls around to find other gooseneck barnacles before permanently settling. They must be near other barnacles for future reproduction.
Eat plankton, cypris larvae, small clams, hydroids, and amphipods.
Glaucous-winged gulls, sea stars, whelks.
Humans eat as a delicacy.
These are such a delicacy in Spain and Portugal, where they are often steamed and then dipped in hot, melted butter, that they can go for 100 Euros per plate!
Though their long stalk looks like a goose’s neck, their name actually comes from a medieval belief that this is where baby geese actually hatched from!
One of the most common organisms found on floating marine debris, their length can be used to give a minimum amount of time the item has been floating out at sea, as their length is proportional to their age.