Small things come in spectacular packages. You can say that about nudibranchs because they might be tiny but they are incredibly beautiful. These bottom-dwelling sea slugs with jelly-like bodies come in different colors, patterns, shapes, and textures. Nudibranchs, fondly called nudis for short, are a sight to behold and many divers look forward to seeing them during their underwater exploration. They can be found in different parts of the world but they thrive in shallow, tropical waters. If you’re scuba diving Fujairah, you’ll most likely come across these gorgeous creatures. Divers who love underwater photography will enjoy taking photos of these remarkable marine animals.
Its scientific name, Nudibranchia, means naked gills. Since they do not have a shell, these tiny creatures live their lives with fully exposed gills. Most species have an oblong shape with feathery gills and horns on their backs. Some of these shell-less mollusks come with thick bodies while others appear flat. In terms of color variations, some nudis have loud, elaborate colors that make them stand out. Other sea slugs, on the other hand, have dull hues to blend with their surroundings.
The smallest nudibranchs are about 0.25 inches while larger species may grow up to 12 inches long. You must be wondering, how many kinds of nudibranchs are there? Well, according to National Geographic, there are more than 2,000 species of nudibranchs but experts continue to discover new ones. They can be categorized into two major types: Dorid and Aeolid – based on the location of their gills. The former breathes through its gills on its back while the latter has feathery horns on its back for breathing, digestion, and defense.
These little carnivores feed on algae, corals, anemones, sponges, and barnacles. Some species even prey on other nudibranchs. Nudis use a pair of highly sensitive tentacles, called rhinophores found on top of their heads to touch, taste, and smell food or other nudibranchs. Their color is influenced by the food that they eat.
Nudibranchs compensate for the lack of physical armor by developing an ingenious way to make their line of defense stronger. These creatures integrate the weapons of their prey and use them to their advantage. Many types of nudibranchs prey on corals, jellyfish, and anemones which have tiny stinging cells called nematocysts. Each nematocyst contains a dart-like tubule loaded with a toxin that is launched when touched. Aeolid nudibranchs eat these creatures without succumbing to the poison of their nematocysts. Instead of being harmed, the nudibranchs absorb the stinging cells at the ends of their cerata. They use it as a weapon when threatened or attacked.
Another incredible trait of the sea slug is being simultaneous hermaphrodites. Nature equipped the nudibranch with the reproductive organs of both sexes so it can mate with any other mature individual of the same species. Incredible, isn’t it? Every nudibranch has the ability to get pregnant and produce as many as a million eggs at one time. To increase the chances of survival, these creatures lay their eggs in a circular manner.
Are you wondering how long these tiny creatures live? Their lifespan varies; some have really short lives (less than a month) while other species can live up to one year.
Encounter nudis underwater
Schedule your next dive with Nemo Diving Center for a chance to see spectacular nudibranchs. We have diving trips in Dubai and Fujairah. Check out our website to see our scuba diving packages.