Hooded mystery #2 – Hooded nudibranch swimming
See last week’s post for Part 1 about Hooded Nudibranchs (Melibe leonina).
This week, I share video showing this remarkable sea slug when it is swimming.
When viewing the clip, try to identify the animal’s “rhinophores”, the structures coming off the animal’s head that allow it to smell its way around. These structures have the shape of mouse ears but they pick up on chemical signals, not sound. In last week’s posting I shared how the Hooded Nudibranchs come together to mate through being attracted by smell (pheromones).
Video from today of a swimming Hooded Nudibranch.
The lobed structures on the animal’s back are the naked (nudi) gills (branchs). They can detach if the hooded nudibranch is threatened and are sticky. Maybe this is so that the predator is distracted by the gills sticking to it allowing the hooded nudibranch to have a greater chance of getting away.

Hooded Nudibranchs (up to 17.5 cm) on Giant Kelp.
I have included a second clip this week too, taken on today’s dive. No Hooded Nudibranchs in it, but Bull Kelp forest visions while on my “safety stop”; a 3-minute rest at 15 feet to offload nitrogen before surfacing. Thought you might like to take a dip with me!
Click here for kelp forest video from today’s dive.
7 Responses to “Hooded mystery #2 – Hooded nudibranch swimming”
jackie these just get better and better. I especially like the written bits as it is helpful to read at the same time as you actually see the animal (for me anyway) rather than reading then seeing and trying to relate. Good job on the website as it is so user friendly.
I LOVE IT. I actually get excited when I see a new post.
thanks
ev
Hello wonderful Ev – really helpful feedback about putting the comments into the clip. Thank you so much for being such an active participant in this (ad)venture.
Absolutely stunning! Are these nudibranches in anyway related to jellyfish? They seem a bit similar or not?
It would have been nice if you had turned round the camera so we could all wave at you from our chairs! I haven’t seen you in years! 🙂
Wanted to let you know that I’ve become a volunteer at EMEG, Emirates Marine Environmental Group (www.emeg.ae) to try and help out the Hawksbill Turtles and Green Turtles in the UAE. I’m so excited! I moved my first nest of eggs last weekend. Will let you know more about it.
Hello Yvonne. Not at all closely related to jellies but so understandable that their appearance confuses people. Jellies and sea slugs split apart in classification at the level of phylum. Sea slugs are mollusc where jellies are cnidarians. Makes my day to know that you involved with EMAG. I don’t think anyone can be the same after an experience like moving a nest of sea turtle eggs or seeing them hatch. More pictures than you could ever want to see of me at the following link Hugs! http://jackiehildering.smugmug.com/People/Marine-Detective-in-action/11379791_ji3gq#799509754_BSvfx
I too like the comments in the video. I think Gord was having a wee nap?
I love your blog/website .
These are amazing videos. Thank-you for sharing your experiences .
My Sister Lise sent me here .
Sending sunshine from Port Alberni .
Nicole – Thank you so much for the encouraging feedback!