Nudibranchs: The elusive butterflies of the sea

The 3,000 species of nudibranchs (noo-duh-brangk) boast more colors than a box of Crayola crayons and most nudibranchs “live no more than a year and then disappear without a trace, their boneless, shell-less bodies leaving no record of their brief, brilliant lives”.

These sea slugs are found all over the world and range in size from a quarter of an inch to just about a foot. The word “nudibranch” means “naked gills”. A name appropriate since their gills are exposed prominently outside of their bodies (not covered like other sea slugs).

These gastropods are remarkable for their defense mechanisms. A listing and description of some are listed below along with some select images of these brilliantly colored sea slugs.

Warning coloration: Bright, contrasting pigments warn prospective predators they’re are inedible.
Skin: They can be can be tough-skinned, bumpy, and abrasive.
Toxic secretions: Some feast on poisonous sponges and then absorb the toxins into their body which are secreted later when disturbed.
Stinging cells: Some accumulate the stinging cells (nemocysts) from their prey (e.g., fire corals, anemones, and hydroids) and then the stinging cells are emanated from their own body when distributed.





I must admit that the title and inspiration of this post came from the book “The Highest Tide” (2005) by Jim Lynch. If you have time this summer it’s a must read if you think you might enjoy an homage to Rachel Carson secretly embedded in a coming of age story set along the coast of Puget Sound.

Image (c) top to bottom:

Well, well, ‘whelk’ what do you know?

It’s no surprise why my home state of New Jersey has been on my mind lately. Using my enthusiasm for nostalgia, I decided to investigate little known facts about the state. Today I am eager to share some at best ‘compelling’, but possibly ‘useless’ knowledge on the New Jersey’s state shell, the knobbed whelk.

Image (c) by Charles Tilford on Flickr: noncommercial use permitted with attribution / share alike.

Image (c) by Charles Tilford on Flickr:
noncommercial use permitted with attribution / share alike.

  1. Governor Christine Todd Whitman declared the knobbed whelk (Busycon carica) the state shell on April 13, 1995.
  2. In addition to being the state shell of New Jersey, the knobbed whelk is also the state shell of Georgia.
  3. The shell of the knobbed whelk is coiled and pear-like and appears anywhere from yellow to gray in adults with purple and browns tints in juveniles. Its inside is typically pink to white and iridescent.
  4. The animal that lives inside the shell is a one-footed member of the sea-snail family (specifically the family, Melongenidae).
  5. Knobbed whelks are found off the east coast of the U.S. from Massachusetts to northern Florida.
  6. The meat of the whelk (and that of the conch) is known as scungilli.
  7. Whelks have a large pair of tentacles, each with a light-sensitive eyespot.
  8. Whelks also have a small pair of tentacles that are used for smell and touch.
  9. The U.S. exports whelks (i.e., knobbed, as well as lightning) to many areas of the world including France, Southeast Asia, Australia, and the Caribbean.
  10. Horseshoe crabs are used as bait to harvest channeled or knobbed whelks.
  11. There is a popular Korean side dish known as golbaengimuchim, which is seasoned whelks with spicy sweet and sour sauce with vegetables.
  12. Knobbed whelks can be up to 12 inches long.
  13. Knobbed whelks and lightning whelks can be distinguished by the difference in their openings. Knobbed whelks are dextral (i.e. right-handed).
  14. Knobbed whelks and lightning whelks lay strings of egg capsules.
  15. Knobbed whelks feast on clams using a radula.