While McMurdo station is about the size of a small town (less than 400 people during winfly), we don’t have to go far to be reminded just how vast Antarctica is. Even in the small area we are working in, the sea ice stretches all the way to the horizon to the north and is bounded by the Royal Society mountain range to the west and south and Mount Erebus volcano to the East. Searching for Weddell seals is challenging in this environment, but we know they are out there!
One danger we have to be especially conscious of while searching the ice, is increased UV radiation. Despite the extreme cold and even overcast conditions, it is still important to wear sunblock on exposed skin. The increased UV levels can also hurt the eyes causing a condition known as “snow blindness” which is essentially a sunburn on the cornea. To protect against it we also wear protective goggles or sunglasses that filter out a higher level of UV radiation.
It takes a few days, but eventually we find our first volunteer! He’s hauled out of a crack near Hut Point and after a quick look at us, he fell back asleep as we watched him. Back at camp we set him up with instruments to measure his depth, orientation, and acceleration to match up with the oxygen consumption measurements we will take as he surfaces after dives.
With the ability of these animals to dive so deep we decided to name them out of characters from Twenty Thousand Leagues Under the Sea by Jules Verne. Our first volunteer was named Ned! Once in the water he is free to dive and forage for food without having to worry about his breathing hole freezing over. We lower our metabolic dome over the ice hole in order to capture his expirations and measure the amount of oxygen he is using as he dives. Eventually he gets bored of science and decides to take off, but not before helping us collect valuable data! Now we just need to wait until he surfaces so we can retrieve our instruments.