Laura Erickson's For the Birds

(Recording of a Common Loon)

Minnesota birders are still rubbing their binoculars in disbelief after the sighting two weeks ago of a Yellow-billed Loon in Duluth. Yellow-bills, the rarest of all loons, breed above the tree line in tundra freshwater lakes, ponds, and rivers in both arctic North America and Siberia. In winter they have a definite preference for saltwater, wintering along the coast of southeast Alaska down to British Columbia. These rare loons have been seen as far south as Baja California, and there’s at least one record on Long Island, New York, but they are accidental in inland North America. There is one other Minnesota record of this species–back on November 16, 1980, one was seen on Lake Winnibigoshish–it made its way to Lake Superior on Thanksgiving. This year’s bird just happened to appear during the Minnesota Ornithologists’ Union’s October Weekend, when many birders were conveniently congregated in Duluth, so a lot of people saw it.

There’s one hypothetical record of a Yellow-billed Loon in Wisconsin, from November, 1979, and I was lucky enough to be one of the few people who saw it. Unfortunately, none of the books available back then listed the most important field marks of this rare bird. The best illustration of a winter bird is in the new National Geographic field guide–it shows all four field marks necessary to identify this bird–the very pale upper ridge of the bill, the dark ear patch, the strongly barred back, and the crown, which appears “double crested.” Common Loons vary quite a bit in their winter plumage, so it’s critical to verify all four of these features if you think you’re looking at a Yellow-billed Loon.

Paleontologists have found loon fossils over 65 million years old, making them contemporaries of Tyrannosaurus rex and Triceratops. Yet loons are the most highly specialized divers of all flying birds. Their legs are placed so far back on their bodies that they are entirely useless on land–the only other birds with similarly placed legs, the penguins, have developed unique abdominal muscles to allow them to stand upright. In exchange for being flightless, penguins can use their tiny wings to propel themselves underwater–the wings of loons are too bulky for this, although loon wings can be used to balance and turn underwater. Loons are excellent swimmers and flyers–their only problem comes in getting from one mode into the other. They have to run along the water’s surface for a long distance in order to get aloft–occasionally they have one or two false starts before getting up. And they make quite a splash when they drop down, too.

Loons are heading south now–by the end of the month just about all of them will be gone. They winter on the east coast and along the Texas gulf, but just so we won’t feel too bad about them abandoning us, they change into their dullest feathers before they go. Sunbelters don’t get to see loons in their beautiful summer plumage, or hear their haunting yodels– loons save their best for summer in the Northland.

(Recording of a Common Loon)
This is Laura Erickson, and this program has been “For the Birds.”