Minnesota and Romancing the Loon
October 6, 1997
The mournful vocalization of the common loon is the stuff of romance novels. When its call echos over the still waters of a small lake, it often evokes an emotional response in humans. But why does it make such a mournful sound? The experts such as Paul Ehrlich, claim that their yodel call signals territorial ownership. But, could it also signal concern that it may never become airborne again? That when the cold winter winds come and the lake begins to freeze over, the poor loon will be frozen in ice? Landing on a small lake is easy, but taking off is something else for a common loon. Becoming airborne requires a major investment in loon energy. Depending partly on how much food it has consumed and is currently digesting, a loon takes off by running upright across the water while flapping its wings as hard as it can. According to the Itasca State Park Wilderness Guide, this “take off” may require from 75 to 1000 feet, depending on the wind. For a loon that has landed in a small lake, leaving the lake can present a formidable obstacle. If 1000 feet are needed, but the lake is only 900 feet wide, what is a self-respecting loon to do? If it tries to take off, only to crash into the alder bushes at the far side of the lake, it will the laughing stock of the wildlife community. The crow flock cavorting in the tops of a stand of white spruce on the edge of the lake will be unable to contain their glee. They will flap and hop and laugh at the poor loon with their raucous cawing sounds. This is serious stuff for the sophisticated loon. Once it becomes an adult, it wears the loon equivalent of a black and white tuxedo all day, every day. But, its self-respect is not the only problem. Stranded on land, a loon - about the same size as a Canada goose - would make an excellent meal for a hungry wolf, coyote, or fox.
Little known to the crows and wolves, the poor loon cannot help his condition. He was born with dense bones - a condition bordering on an affliction when it comes to flight. But when diving and swimming after fish, the loon could compete for an Olympic medal of the animal world. It must be able to outmaneuver and swim faster than the small fish and crayfish if it expects to catch them. Its heavy, dense bones allow it stay submerged in water. The bones of most birds are honeycombed with air cells which makes them very light. Thus, they are adapted for flying. But, when migrating south in the fall, if these light-boned birds become lost over water, they are in serious trouble. A loon is at home in water. Leaving the water constitutes the dilemma. Sometimes on a small lake, it is not too difficult to imagine that a loon must go on a crash diet to lose the few ounces needed to become airborne. An obese loon under such conditions would be even heavier. Because of its heavy bones and heavy body, how does it gain altitude quickly enough to fly over the cattails rather than into them? Then if it gains sufficient altitude to clear the cattails, it must still clear the alder bushes, and finally the spruce and tamarack trees surrounding the lake. A young loon might find this problem perplexing, but a savvy, adult loon knows to make a sharp turn once it is airborne, and keep circling around the lake while gaining altitude. It spirals up and up until it is finally free of water, the wild rice, the cattails, and the trees - free to land on the next small lake where it can start the process all over again.
Why are loons not common in Texas? Maybe it has something to do with the distance between lakes. They have earned the title of “Minnesota’s state bird,” and an estimated 12,000 birds make their home on the more than 10,000 lakes. It is claimed that they are one of the earth’s oldest living bird species - having inhabited this earth about 60 million years. While boating on Lake Rainy on the Canadian border, we witnessed the unusual (for us) flock of 15 loons swimming together. Usually, we see only single individuals out in the middle of the lake. Their low profile in the water, heavy, pointed beak and white front distinguish them from double-crested cormorants and other swimming birds. But they do not overwinter in Minnesota. Like the human “snow-birds” from this state, loons overwinter in more temperate climes such as Florida. Having never seen a loon on land, I do not know if their movements would be clumsy. But, I expect that a loon on foot in the Texas mesquite brush would certainly startle the most experienced birder.
John Ludwig, one of the Itasca Park managers, has been kind enough to allow me to use the park phone for a few minutes to send and receive email. I better make a quick visit with him before he forgets.
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