Ask the Aquarium: Plant or Animal?
BY SHERRY WHITE
Special to The Pilot
Q. What is the orange plant with thin branches and a small round disk at the bottom that we find washed up on the shore? Does it grow in the water or on land?
A. What you've described does indeed look like a plant, but actually it's an animal - a type of soft coral called a sea whip. In our area, sea whips come in two varieties: Leptogorgia virgulata, and the regal sea fan, Leptogorgia hebes. Colors vary and can be orange, yellow, rust, white and occasionally purple.
These marine animals with lovely frond-like stems exist as a colony, consisting of a wire-like skeleton and several branches. They live and grow underwater, and the round disk at the bottom of their central stalk acts as a holdfast, attaching to solid objects where the whips spend their lives. Their thin branches can number a few or many.
Unlike hard corals, sea whips are flexible and sway gracefully in waves and currents. They feed on passing plankton by extending thousands of tiny polyps from minute pore-like openings visible on their branches.
When found onshore, the polyps have withdrawn and the sea whip resembles a colorful, leafless plant. Strong storms or constant battering can dislodge sea whips from their anchorage and deposit them on beaches and along shorelines.
Information is provided by the North Carolina Aquarium at Pine Knoll Shores. The state operates three public aquariums; one in Pine Knoll Shores, another at Fort Fisher and a third on Roanoke Island.
The aquariums are administered by the North Carolina Department of Environment and Natural Resources, and are designed to inspire appreciation and conservation of North Carolina's aquatic environment.
For more information about the Aquariums, visit www.ncaquariums.com, or call (800) 832-FISH.
Sherry White works for the public affairs office of the N.C. Aquariums.
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