In conjunction with National Sea Slug Day last Monday, the California Academy of Sciences released colorful photographs of 17 newly identified nudibranch species.
Striking colors and unusual color patterns were given a special focus in a genetic study that is helping to group the nudibranch species and understand how they evolved. Hannah Epstein, affiliated with the California Academy, was the lead author on the research paper published in the Zoological Journal of the Linnean Society.
Nudibranchs, soft-bodied mollusks often called “sea slugs,” are among the most ornately decorated creatures in the sea. With about 3,000 species of nudibranchs coming in all shapes and colors, I thought it might be fun to track down some of these animals.
Nudibranchs are found in all the world’s oceans, but you don’t need to go beyond Puget Sound to find some of the most beautiful ones. I’m grateful to Dan Hershman, a retired Seattle teacher, part-time musician and underwater naturalist, who shared some of his best photos of sea slugs from this region. Check out Dan’s Flickr website.
The word nudibranch (pronounced nude-eh-brank) comes from the Latin word nudus, meaning naked, and brankhia, meaning gills. So these are animals with naked gills, which often grow out of their backs and sides. These creatures can be as small as a quarter-inch or as long as a foot or more.
Nudibranchs are carnivores, eating things ranging from algae to anemones, barnacles and even other nudibranchs. They can pick up coloring for camouflage and even poisons from the prey they eat, using the chemicals in defense against predators.
Hermaphrodites with reproductive organs of both sexes, these animals don’t normally self-fertilize. But they are prepared to mate with any mature individual of the same species. Eventually, they will lay masses of spiral-shaped or coiled eggs.
For more great pictures, check out Bored Panda’s collection, the 500PX photo gallery or National Geographic’s page of David Doubilet’s photos. If you would like to join a sea slug fan club, visit Slug Site, home of Opisthobranch Molluscs..
