Sea slugs – celebrating hidden gems in the ocean
By Alicja Szalanska
Volunteer, Wild Coast Sussex
The 29th October marks International Sea Slug Day, a celebration of these captivating yet often overlooked oceanic wonders. It’s also a day to acknowledge the lifelong dedication of marine biologist Terry Gosliner, who has tirelessly studied and conserved these remarkable creatures. In this post, let’s dive into the world of sea slugs.
Sea slugs, or nudibranchs, are diverse marine molluscs found in all the world’s oceans, from shallows to the deep sea. These slow-moving grazers consume algae, sponges, and other small invertebrates, showcasing a range of feeding habits.
Sea slugs are renowned for their vibrant colours and intricate patterns, which often serve as warning signals to predators due to their toxicity. They get their toxicity from the creatures they eat, and some sea slugs can even keep the stinging cells of jellyfish inside their bodies.
Beyond their striking appearance, sea slugs possess other intriguing traits. Some can photosynthesise, producing their own food with sunlight. Others regenerate lost limbs, and a few can steal genes from their prey and incorporate them into their DNA.
Sea slugs play a vital role in marine ecosystems by controlling algae and serving as a food source for various animals, including fish, birds, and crabs.
Sussex offers an excellent opportunity to discover sea slugs along its coastline, including species like Sea Lemons and Grey Sea Slugs. The summer months, with warmer waters and increased activity, are the best times for spotting these creatures. They can be found in diverse habitats, from rock pools and seaweed beds to coral reefs.
When searching for sea slugs, keep a sharp eye out for small, brightly coloured creatures that often blend into their surroundings. Take a moment to appreciate their beauty and unique features. Sea slugs are truly amazing and deserve our respect and admiration.