First of all: What even is a sea slug?
Well, I'm glad you asked. (pretend you asked)
A sea slug is just the name for a gastropod (slug) that lives in the sea. Some of the sea slugs listed below are Nudibranchs, although not all Nudibranchs are sea slugs because it also includes some sea snails and sea hares. Nudibranch actually means "naked gills" which means they have exposed gills. These gills often look like adorable poofy tails!
Some sea slugs also have antennae or ear looking things coming out of their heads. These are called rhinophores and are actually used to in a way smell chemical signals in the water! Sea slugs are also both biologically male and female at the same time which is really cool.
Next I'll list some of my favorite sea slug species and some cool things about them!
I promise its interesting...
First: A Leaf Sheep!
Leaf sheep are unmistakably adorable. You might have seen them before, with their goofy faces and green leaf-like bodies. But leaf sheep can actually do something really interesting!
Leaf sheep are known for their ability to indirectly photosynthesize! They are the only animal capable of this. They pull this off by essentially stealing the chloroplasts from the algea cells they eat, and repurposing them for their own benefit.
What a peaceful existence....
Second: The Orange-Peel Doris!
These guys are seriously my favorite thing ever. They are named after the fact that they look like little bumpy orange peels, with white gills and dark orange Rhinophores.
They're brightly colored because of aposematic coloration, which means they're colored that way to warn predators that they taste bad. Many sea slugs are poisonous to some degree. They also feed on bryozoans, tiny organisms.
Next: The Blue Dragon!
Blue Dragon sea slugs are some of the most interesting out there! They are well known for their sting, but the interesting part is how they get that sting.
Blue Dragons eat the Portuguese Man-O-War, a jellyfish with a dangerous sting. The sea slugs are immune to the sting, and when they eat the jellyfish they repurpose the stinging cells into their own self-defense.
Next: Elysia Marginata!
These guys look like normal sea slugs at first sight, but they are well known for a super interesting ability. E. Marginata is found off of the coast of Hawaii and Tahiti, whith orange and black bands on its body.
The ability they are known for is that they are capable of shedding their heads entirely and growing a new body when under threat! They are the only sea slug able to do this, and the process is extremely strange to watch.
Next: The Black Sea Hare!
These things are the biggest sea slugs, and they are absolutely gigantic. They are all black, and don't have exposed gills like many of the other sea slugs I have listed.
They feed on seaweed and kelp, which actually give it its dark color. They can be found in California and Mexico, and live for only a year.
Finally: Sea Angels!
Sea angels are my absolute favorite animal ever. These free-swimming sea slugs are both interesting and beautiful, with transparent glowing bodies.
They move a lot differently than most sea slugs, swimming with their wing like body parts called parapodia. They are carnivorous, and some species specifically feed on another creature called a sea butterfly. They eat by using small tentacles that emerge from their head, kind of terrifyingly for such adorable creatures.
