8/12/2012 3:16:39 PM
Summer Studies in Svalbard
Each spring and summer as the sea ice melts much of the Arctic Ocean undergoes a massive change from a bleak and barren frozen desert to a vast blue sea with some of the highest productivity in the world. What drives this remarkable change, and how does it influence the rest of the arctic ecosystem? This was the main premise of my studies in Norway where I spent the last six weeks at the University Center in Svalbard (UNIS).
UNIS is a unique facility, not only because its resides in Longyearbyen, the most northerly town in the world, but also because it provides aspiring arctic scientists from around the world an opportunity to work and learn in a very hands-on way. Courses here cover a wide array of disciplines and academic levels. Undergraduate and graduate students alike can take courses in biology, physics, geology or technology, each with its own unique fieldwork component.
My course in Arctic Biology dealt specifically with the transfer of energy and nutrients from the sea to the land. That is to say, how does a very productive marine ecosystem help to fertilize the relatively barren terrestrial landscape? The long and short answer is ... seabirds! In the springtime, Svalbard is inundated with millions of seabirds from around the globe. Although some of these birds are year-round residents, most migrate there to take advantage of the abundant food sources and to breed on the rocky cliffs. Probably the most ambitious migrator is the arctic tern, which overwinters in the Antarctic and returns north every spring -- almost 20,000 kilometers one way!
Seabirds in particular have high energy costs. Flying is essential for these creatures, but it is very energetically expensive! Furthermore, they often have to trade-off efficiency of flight for the ability to dive to catch food. You can think of many seabirds as a cross between a penguin (a diving expert that is unable to fly) and a gull (a flying expert that dives very poorly). Because flight burns so many calories, seabirds need to eat a lot of food each day just to maintain their current size (up to 80% of their body mass in a day!). This demand increases even more in the springtime, when adult seabirds also need to bring home enough food to feed a brood of chicks.
A simple fact of life states that the more food taken in, the more waste produced; in birds that waste is called guano. Birds nest on the cliffs and fly out to sea to feed. This results in much of the guano produced falling on the land between the cliff and the shore. Guano is very nutrient rich, while the landscape it is falling on is very nutrient poor. In this way, droppings fertilize the landscape and allow plants to thrive where they were previously couldn't. It may seems like a single small bird would have a negligible influence, but when you consider colonies of birds as large as 200,000 the amount of nutrients transferred in a season measures in tens of tons!
On Svalbard, cliffs that house a bird colony can be easily identified by the lush carpet of green along the base and the lower slope. The fertilization of so many birds creates an oases of vegetation growth that is essential for herbivores such as reindeer, goose, and ptarmigan. Whether it is fish, plankton or even other birds, all of the food that is consumed by the seabirds gains its energy and nutrients from the base of the food web - the phytoplankton. In this way, the very productive waters of the Arctic Ocean provide fertilization for the terrestrial plants, food for the herbivores, and help to sustain a healthy arctic ecosystem.
Although my research is focused on polar bears, I believe it is essential to have a broad understanding of all arctic ecosystems and to recognize the important linkages between them. As my time on Svalbard comes to an end, I will take the knowledge and experience gained from UNIS and apply it to my own research as I move forward with my masters project at the University of Alberta. I encourage any young and aspiring scientists who want to study arctic systems to consider doing a semester of study at UNIS in Svalbard. The experience is unforgettable and just being there, in the heart of the Arctic, is inspiration enough to make you want to work to protect this treasure for all generations.
Top photo copyright Helga Kristiansen; arctic terns, copyright Kt Miller/PBI; guillemots, copyright Henry Harrison/PBI; cliffs fertilized by guano, copyright Patrick Mislan.