Ben MacShane will be the first to admit that he is a lucky guy. So lucky, in fact, that he got to go on an adventure that most people can only dream of. But what I love about Ben is that he will turn what he learned on this elite educational trip into powerful action. He has been passionate about the ocean all his young life, sailing small boats on the North Shore, exploring and observing. Watch out! We will hear from Ben again. He is already a steward of the sea.
Here is a blog Ben has written about a very important part of his trip to Antarctica.
My name is Ben MacShane and I am a sophomore at the Hotchkiss School in Lakeville, Connecticut. I returned in January from the South after a very eventful trip, not only did we encounter the incredible animals of South Georgia, but we also met with a Force 11/12 Antarctic blast. Force 12 is a hurricane. This hurricane gave us all the Silver Explorer, our ship, could handle, and then some. At around 4:45pm in the middle of the storm, a monstrous wave smashed the front of our ship. The rogue wave smashed in one of our bridge window, water, glass, and crew were smashed into the back wall of the bridge. It was a very traumatic experience, I actually saw three crew running down the hall to the infirmary, soaked in blood, head to toe. Our ship limped back to Ushuaia under a single engine and limited electronics, but in high spirits. Even though we were cut short, I took back an incredible amount of knowledge. During our long cruises to the islands and back to Ushuaia, we had three lectures a day. The lectures ranged from Shackleton to elephant seals to the winds and currents of Antarctica. Here is a combination of a few lectures wrapped into one essay!
The affect of global warming on the Krill population in Antarctic by Ben McShane
There are 100 trillion krill in the world’s oceans today, however, these krill are in danger, it is not the hunting sea lions or the blue whales, its the warm temperatures in the Souther Ocean. These krill account for the single largest biomass of any single species on earth, 500-700 million tons. Why are there so many of them? They are excellent at what they do. At only two and a half inches and about .7 ounces, a single krill can live for up to six years. Krill have an arsenal of natural survival tools that range from illumination to diet. All of these adaptations enable them to live a long life. For 260 days a krill can fast, now this may seem plausible because they could live off of their fat stores like many other animals that go without food for extended periods of time. But here is where krill have adapted. No other animal can do this: Krill actually burn their muscle and slow down their swimming to survive when going without food. Why? Antarctic waters can be as cold at twenty-eight degrees, the freezing point of salt water. Without their fat, the tiny krill would die within days; this is an incredible example of evolution in the Southern Ocean. The krill aren’t done there, these supreme survivors have a few more traits that aid in their survival in the brutal Antarctic. Speed: these tiny animals have an efficient swimming motion that allows them to shoot through the water at speeds of up to four to six body lengths per second. Can you imagine if we could move that fast? I’m about six foot three, and it would be very helpful to move more then thirty-six feet per second! At these speeds they can elude the most agile fur seal, maybe not a blue whales gapping mouth though. To elude the whale however, in an all out sprint, a krill can flick its tail instead of using its legs, and move twenty-five body lengths a second! Second, and perhaps the most sci-fi esq. are the lights that krill possess. Since krill are predominately clear, they use ten lights along their backs to light themselves up when at depth. Just as penguins and sharks have colorations to camouflage themselves with their surroundings, dark from the top, light from the bottom, krill appear as sunshine from below with their lit up bodies. If that was not enough, krill have the ability to actually shed their skin in order to confuse a predator, in no time at all, the hard outer shell can be slipped off as the krill escapes in the opposite direction. Perhaps krill’s most effective defense, lies in numbers. A school of krill can pack into a ball so tight that in one square meter of that school, 50,000 krill can be found. These massive gathering are an effort to literally increase each krill’s probability of living, if there are millions of them together, a krill’s only hope is that he is one of the lucky ones!
Despite every effort these krill make, they serve as the building blocks of an eco-system that supports the largest animals on the planet, and everyone in between. This means a great deal of them get eaten. To be more exact, a single fur seal can eat a ton of krill a year; there are three to four million fur seals in Antarctica. A blue whale needs four tons of krill a day to survive. An Adelie penguin colony can eat up to 8,000 tons a day. In total, the estimated number of krill eaten in one year in Antarctic waters is 310 million tons. In addition, fisherman take 100,000 tons a year, but that is relatively insignificant compared to the real inhabitants of the ocean.
It is clear that krill are very special creatures. Every animal in the Antarctic depends on their population’s well-being in some way. So what happens if the krill begin to die. We are in the process of finding out as we speak. I know it sounds cliche, but it couldn’t be more true, it all comes back to global warming. Krill do eat, despite how much I have talked out them being eaten. A single krill can actually clear a square foot of algae from the bottom of a piece of sea ice in about ten minutes. This algae is incredibly important to the young krill who are not strong enough to fight the currents of the ocean, as they try to find food in the open water. So, when they are born, they float to the surface where the sea ice is, and feed off of the algae attached to the bottom of the ice. There is one problem however, the ice that holds this algae is melting, and as that ice melts, the speed at which is calves and crumbles increases. Ice is white, meaning it reflects the sun, and it’s heat. So people think the sun is melting the ice from the top, they are wrong. The sun is attracted to dark surface, where it can be absorbed. That dark surface in Antarctica happens to be the ocean, and so the more ocean that is exposed by calving ice shelfs, the more heat is absorbed from the sun. Thus, the ice is actually being melted from below by the ever warming water. This can not be stopped. Once it begins, the only way for it to stop is for the climate to actually reverse, and begin cooling.
The ice supports everything, animals live on it and krill feed off of it. Without this essential piece of the south, the Southern Ocean is in trouble. As this ice melts more and more everyday, more and more baby krill never make it to adulthood (to be eaten, its a rough life isn’t it). Last year in under forty days a massive ice shelf on the eastern side of the Antarctic Peninsula calved, dumping thousands of square miles of ice into the ocean. That’s thousands of square miles of algae for krill to eat, GONE.