By: Arin
I’ve lived in the Arctic Circle for almost a year now. Studying ecology here, one of the most important things we learn about and then witness for ourselves is the massive impact and scale of the annual migrations. When I arrived in the fall there were a few bird species around, the tundra was red and orange and the days shortened almost imperceptibly. By the first snowfall I noticed that most of the songbirds I had gotten used to seeing were gone. By December the only birds I could still see were rock ptarmigan, hooded crows, eiders, some gulls, magpies, and the occasional waxwing and redpoll. In the throes of the polar night the sun was down by 12:30 in the afternoon and the only light was a slight twilight in the morning that turned the white mountains blue. My long dark walks home from classes were often under ribbons and mists of northern lights and the skeletons of trees. Everything had either left for the winter or was slowly enduring it by the grace of evolution.
As spring approached though, the days got longer and the snow started to melt. The trees budded again and I started to notice new birds in the trees that I hadn’t seen in months. Spring turned into summer and dozens of new birds appeared all over the arctic island along with fields of wildflowers and grasses. Whales started to be spotted in the fjord and it was like the entire arctic was coming back to life. Nowhere was this influx of migrants more apparent though than the island of Svalbard in the high Arctic, 650 miles from the North Pole. Since I've been here for the last two weeks, the seemingly barren rocky landscape is flush with millions of seabirds and the fjords are filled with whales. I spent several cold hours under a little auk colony where huge flocks of the tiny penguin-like birds formed murmurations in the sky. Black-legged kittiwakes nested in the windows of abandoned buildings and puffin chicks could be seen hiding under rocks and peeping when you approached.
left to right: arctic tern over the fjord, Brünnich's guillemot raising chicks on the cliffs, little auk colony, black-legged kittiwake and chick.
I knew that migration was a common natural feat, but I didn’t quite realize its scope or importance until I started to study how necessary it was to the existence of the Arctic. There were 283 bird species known to nest on the island of Tromsø where I studied, but only 88 remained in winter. That was about 200 new species returning in the spring.
In the early days of ecology, without the benefit of technology or reliable communication, many people thought birds buried themselves in the mud for the winter or transformed into the common winter species. That they flew to the moon was a widely held scientific thought, while it was suggested that barnacle geese grew on trees like fruit and so miraculously appeared in the summer.
As we know now of course, these species embark on months-long migrations over incredible distances. There are 1,850 migratory bird species in the world, some 19% of all the extant species. The arctic tern holds the record for distance as it travels 80,000 km round trip between the poles every year. Others fly from South America to Northern Canada, New Zealand to Alaska, Northern Europe to South Africa. Flocks of birds can block out the sun and fill fields for miles on their migration pathways north and south. Most of the species left the arctic during the winter because they could not survive in the extreme cold and dark. But why would they fly so far north in the summer when it was so taxing a journey? Svalbard is a long way north after all, so what would make a bird fly across the equator to get there when they could nest anywhere in between?
It turns out birds flock thousands of miles to the Arctic for one of the same reasons I did: there's fewer bugs. In the Arctic there are significantly fewer parasites and pathogens, as well as predators. It is a safe haven where the only real dangers are the occasional arctic fox and maybe a glaucous gull.
When I was driving in a small boat past the huge eroding cliffs of Spitsbergen in Svalbard I could easily see where the seabird colonies were. There are cascades of olive brown moss falling down the cracks of these cliffs like water, but near the colonies, the vegetation is a vibrant green from the nutrients of seabird poop. Almost nothing lives on Svalbard during the winter. The polar bears and arctic foxes retreat to the sea ice and only the fat, short Svalbard reindeer and ptarmigan brave the long dark months. So when some 4 million birds return in the spring and bring with them the nutrients and resources of the much more productive south, there is an explosion of life taking advantage of the short warm months of summer. Arctic foxes shed their winter coat for tundra-colored camouflage and prowl below the cliffs for eggs and stray chicks. Little auks stuff their tiny mouths full of krill for their chicks and scatter in panic when a glaucous gull circles overhead, ready to swoop down and snatch up any chicks foolish enough to sit too close to the entrance of their cave (A feat I witnessed).
from left to right: Atlantic puffin with food for puffling, snow bunting feeding chick, arctic fox below the little auk colony, little auk with a face pink from krill
The returning migrants are essential to the arctic ecosystem surviving through the winter, but their arrival and populations are in a delicate balance that is often disrupted by the activities of humans and climate change.
Over the last few years seabird populations have been fluctuating for the worse, with massive shipwrecks of dead birds washing onto beaches. They starve as their food sources dive deeper into the ocean in search of colder water and the rising temperatures affect their internal clocks as they migrate too early and miss the fish migration. Too many geese from new regulations and food sources further south cause huge overgrazing and destroy whole areas of vegetation that cannot recover for decades. When I peered into puffin caves for my research I found pufflings sitting in nests lined with plastic. Remote beaches were washed up with trash and almost every species of seabird has some form of pollutant in its blood stream.
I’ll be returning to the mainland in time for the start of fall and the birds will start to vanish once more to more forgiving climates. Some seabirds will spend their entire winter floating in massive rafts on the open ocean, others head to Africa and southern Europe. Migratory birds connect ecosystems across continents and ensure a flow of energy across the planet. It was amazing to witness these seabird species nesting in the tundra and cliffs of the high arctic and to see the return of the birds in the spring, the songbirds and waterfowl building their nests in the trees and around the lake of the mainland.
I don’t think anywhere else is the effect of the migratory birds more evident than the Arctic. It’s beautiful to see the once-frozen lake filled with red-throated loons and common tern nests and strings of ducklings across the water under the watchful eye of a gray heron. The entire Arctic blooms with life and activity in the spring and it is all heralded and even driven by the returning flocks of birds.
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