One of my favorite experiences in Antarctica was dive tending. Back when I was just a wide-eyed college phycologist, I spent a summer coring ice and running samples out of McMurdo station. Across the hall, two guys named Mark spent their days under the ice, picking up anything unusual and bringing it back to the lab to give it a name and grind it up. Rumor had it they even ate a few nudibranchs, in the name of science. While my samples were running through the various testing machines, I could take a couple of hours and head down to the edge of the ice with them, spooling out the rope that would lead them back up.
The job of the dive tender is not taxing. You must keep the rope taut, so it doesn't tangle on rocks or ice. If you see an orca nearby -- or worse, a leopard seal -- you give a series of short warning tugs. Leopard seals were particularly notorious for chomping divers. Otherwise, you let your lab-weary eyes take in the vast beauty of the Ross Sea, with tiny penguins picking their way across the ice. When the Marks return, their mesh bags contain sponges, corals, and other strange animals surprisingly brightly colored for life that never sees sunlight.
I'm reminded of this by an article in the current issue of American Scientist: Ecological responses to climate change on the Antarctic peninsula. Down in MacTown, we called the peninsula the "banana belt" for its relatively milder temperatures. Heck, they even have plants. Now, it seems the banana belt is getting even warmer, both in the sea and on land.
Dr. James McClintock (lead author and former advisor to one of the Marks) describes a world where salps supplant krill at the base of the food chain, and sponge-crushing crabs move into the invertebrate gardens. Even if you're not a regular sci-journal reader, check it out for the introduction and the illustrations.