Sea pens are octocorals or colonies with polyps having eight tentacles.  It’s amazing that some sea pens have very long life spans and may live for 100 years.  Their name comes from one form that resembles an old fashioned quill pen, but other forms resemble a club, a flower head with long stalk, or narrow whip.  Sea pens have a few defence mechanisms to protect themselves.  Some sea pens like the orange sea pen here on the west coast can expel most of the water in its tissues and retreat into the sand if threatened.  Sea pens can also dislodge themselves from the ocean floor and float away from a predator.  These colonies also produce a green bioluminescence if disturbed, which some believe may be meant as a means to scare off a potential predator.  Sea pens are an ancient order that fossil records have shown to exist for at least 540 million years.