At Sea

Having crossed the convergence early this morning, Endeavour has truly left the Antarctic environment and is heading to what some call the “tropics” which are the Falkland Islands. This expedition has been a transit through different environments, starting with the harsh ice-covered world of the Antarctic Peninsula, heading on to the wind swept and glacially covered mountains of South Georgia, and now to the wind swept, yet lush green environs of the Falklands.

Not only has the terrestrial environment has changed on this trip, but also the aquatic realm. Certainly the underwater world will change as we arrive in the Falklands; no longer will small Antarctic fur seal pups be porpoising through the water, rather South American sea lions or sub-Antarctic fur seals will be our guides. The benthic community will take on a whole new look, living in 50°F water, as hermit and spider crabs scurry across the bottom and jellyfish move gracefully through the water column.

So one last look back at the wild and wooly creatures of the Antarctic. Sometimes it is the smallest and most delicate creatures that can fool you and wreak the most havoc on their neighborhoods. Pictured here is Notaeolidia gigas from South Georgia. The nudibranch is essentially a snail without a shell. You will notice that the body of this nudibranch is translucent to milky white, and are the tips of the cerate (the lion’s mane of tentacles found on the nudibranch’s back), rhinophores (second antennae), and oral tentacles are pink. Many nudibranchs are colored such as this, and in many cases more brilliantly, which may serve as a warning system for predators and/or a camouflage. It is thought to feed on hydroids and sponges, but some studies have shown that it will eat anemones and soft corals. N. gigas will consume creatures such as the hydroids, who have nematocysts, or stinging cells (the same as jellyfish). After they consume these creatures, these nematocysts will migrate to the end of the cerate, where they are used as defense mechanisms by the nudibranch.

The nudibranch is just one of the new and interesting wonders that we have found on our trip to Antarctica and South Georgia. And with this picture, we bid a fond farewell to Antarctica and all its weird and wonderful underwater animals - at least until next year…