The far side of the sound (where Michael’s post described the trip out to) is very different underwater. Sandy, non-volcanic rocks and lots of different types of life.
There are still sponges but many different kinds of animals that we don’t really see near McMurdo station. Especially scallops which cover the seafloor.
While we get Crinoids on both sides of the sound, there were two at the site that we were working at. I only saw one, but it was a pretty one. These are closely related to star fish, sea urchins, and sea cucumbers and swim by waiving all their arms in a rhythmic pattern. We didn’t see any swimming though.
And in addition to the life on the seafloor, the algae growing on the underside of the ice, truly made the place special.