Of Sea Whips and Sea Pens
Awestruck yet again.
My buddies and I discovered a “garden” of Sea Whips and Orange Sea Pens at only 65′ (20 m).
These are the most surreal looking organisms.
They are octocorals – colonies of 8-tentacled polyp-like animals. The polyps filter feed on plankton.
The Sea Whips can reach a height of 2.5 meters (Halipteris willemoesi). Orange Sea Pens can be 48 cm tall (Ptilosarcus gurney).
Information on Orange Sea Pens from the Monterey Bay Aquarium “A graceful creature of the seafloor, this sea pen resembles a plump, old-fashioned quill pen. Its colors range from dark orange to yellow to white. Each sea pen is a colony of polyps (small anemonelike individuals) working together for the survival of the whole. The primary polyp loses its tentacles and becomes the stalk of the sea pen, with a bulb at its base—the bulb anchors the sea pen in the muddy or sandy bottom. The various secondary polyps form the sea pen’s “branches” and have specialized functions. Some polyps feed by using nematocysts to catch plankton; some polyps reproduce; and some force water in and out of canals that ventilate the colony.”
But this may be another case where images speak louder than words.
Please enjoy the following photos and clips of Sea Whips and Orange Sea Pens and . . . the predators that stalk them.
Nudibranch fan alert !
2.5 minute clip below is of Sea Whips and Orange Sea Pens and the predators that stalk them.
Video: 1-minute of an Orange Sea Pen and Graceful Decorator Crab in the current in front of Port McNeill, BC.
The BBC video below is from SW Tasmania in Australia, NOT Northern Vancouver Island, British Columbia and shows a different species of sea pen. However, I have included it as it shows, with time lapse photography, how sea pens can slowly deflate and retract in response to predation attempts by nudibranchs.
For more information:
- Dr. Ronald L. Shimek; Reefkeeping; “The Life and Death of Sea Pens”
- A Snail’ Odyssey – “Sea Pen: Predators & Relatives” (brilliant summary of research)
- A Snail’ Odyssey – “Sea Pen Burrowing”