The Loon

 

  Folly Cove profiles, clockwise:

Great cormorant, Red-throated loon, Common loon

 

These three deep-diving birds with similar profiles can be seen along the winter shoreline around Halibut Point. They swim low in the water, unlike ducks. Their long necks and up-tilted heads, giving a snake-like impression, enable them to strike forward at the fish they pursue below the surface. Their beaks are variously specialized for the hunt. The cormorant's beak is hooked at the end, for grasping. 


Common loon surfacing with a crab

The loon has sharp, rearward-pointing projections on the roof of its mouth and tongue that help it keep a firm hold on slippery fish. It consumes most of their prey underwater. This one must have found the crab difficult to swallow.

Unlike most birds, loons have solid bones that make them less buoyant and better at diving. They can quickly blow air out of their lungs and flatten their feathers to expel air within their plumage, so they can dive quickly and swim fast underwater. Once below the surface, the loon’s heart slows down to conserve oxygen.

Common loon in breeding plumage

Common loons molt into breeding plumage just before or after leaving our area for their nesting areas in northern lakes and marshes, where they are known for their spectacular vocalizations.

Common loon in drab winter plumage

The parents head back this way on migration in the fall, leaving juveniles to gather into flocks and make their own journey south a few weeks later. Once the juveniles reach coastal waters, they stay here for the next two years.

Loon preening

The loon propels itself powerfully and with great agility using its large webbed feet. It dives as deep as 180 feet. Although its dives usually average under a minute, loons have been known to stay underwater for as long as 15 minutes and cover a great distance, leading birdwatchers mystified at their disappearance.

 
Common loons need from 30 yards up to a quarter-mile (depending on the wind) for flapping their wings and running across the top of the water in order to gain enough speed for lift-off. Migrating loons have been clocked flying at speeds more than 70 mph.

Common loon in flight

In flight the Common loon is distinguished by its dark upper body, large trailing feet, straight heavy bill, and pronounced collar.

Red-throated loon

By contrast, the Red-throated loon's size and proportions are smaller, its bill slim and upturned, and lacking a collar. We see it here in muted winter plumage without the determinant colorful throat. In flight its head and neck droop below the horizontal, giving the flying bird a distinctly hunchbacked shape. Its thin wings are angled back with a quicker, deeper wingbeat than other loons.

This species is capable of taking off from the water without a running start. Unlike the others, it can take off from land. The Red-throated loon breeds primarily in Arctic regions and coastal tundra, often on very small lakes.

 

The Red-throated loon is seen much less frequently around Halibut Point than the Common loon. It figures prominently in creation stories of indigenous groups throughout the Arctic. In the mythological telling, the loon was asked by a great shaman to bring up earth from the bottom of the sea. That earth was then used to build the world's dry land.

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The Loon on Walden Pond, as told by Henry David Thoreau

As I was paddling along the north shore one very calm October afternoon, for such days especially they settle on to the lakes, like the milkweed down, having looked in vain over the pond for a loon, suddenly one, sailing out from the shore toward the middle a few rods in front of me, set up his wild laugh and betrayed himself. I pursued with a paddle and he dived, but when he came up I was nearer than before. He dived again, but I miscalculated the direction he would take, and we were fifty rods apart when he came to the surface this time, for I had helped to widen the interval; and again he laughed long and loud, and with more reason than before. He manœuvred so cunningly that I could not get within half a dozen rods of him. Each time, when he came to the surface, turning his head this way and that, he coolly surveyed the water and the land, and apparently chose his course so that he might come up where there was the widest expanse of water and at the greatest distance from the boat. It was surprising how quickly he made up his mind and put his resolve into execution. He led me at once to the widest part of the pond, and could not be driven from it. While he was thinking one thing in his brain, I was endeavoring to divine his thought in mine. It was a pretty game, played on the smooth surface of the pond, a man against a loon. Suddenly your adversary's checker disappears beneath the board, and the problem is to place yours nearest to where his will appear again. Sometimes he would come up unexpectedly on the opposite side of me, having apparently passed directly under the boat. So long-winded was he and so unweariable, that when he had swum farthest he would immediately plunge again, nevertheless; and then no wit could divine where in the deep pond, beneath the smooth surface, he might be speeding his way like a fish, for he had time and ability to visit the bottom of the pond in its deepest part. It is said that loons have been caught in the New York lakes eighty feet beneath the surface, with hooks set for trout -- though Walden is deeper than that. How surprised must the fishes be to see this ungainly visitor from another sphere speeding his way amid their schools! Yet he appeared to know his course as surely under water as on the surface, and swam much faster there. Once or twice I saw a ripple where he approached the surface, just put his head out to reconnoitre, and instantly dived again. I found that it was as well for me to rest on my oars and wait his reappearing as to endeavor to calculate where he would rise; for again and again, when I was straining my eyes over the surface one way, I would suddenly be startled by his unearthly laugh behind me. But why, after displaying so much cunning, did he invariably betray himself the moment he came up by that loud laugh? Did not his white breast enough betray him? He was indeed a silly loon, I thought. I could commonly hear the splash of the water when he came up, and so also detected him. But after an hour he seemed as fresh as ever, dived as willingly, and swam yet farther than at first. It was surprising to see how serenely he sailed off with unruffled breast when he came to the surface, doing all the work with his webbed feet beneath. His usual note was this demoniac laughter, yet somewhat like that of a water-fowl; but occasionally, when he had balked me most successfully and come up a long way off, he uttered a long-drawn unearthly howl, probably more like that of a wolf than any bird; as when a beast puts his muzzle to the ground and deliberately howls. This was his looning, -- perhaps the wildest sound that is ever heard here, making the woods ring far and wide. I concluded that he laughed in derision of my efforts, confident of his own resources. Though the sky was by this time overcast, the pond was so smooth that I could see where he broke the surface when I did not hear him. His white breast, the stillness of the air, and the smoothness of the water were all against him. At length having come up fifty rods off, he uttered one of those prolonged howls, as if calling on the god of loons to aid him, and immediately there came a wind from the east and rippled the surface, and filled the whole air with misty rain, and I was impressed as if it were the prayer of the loon answered, and his god was angry with me; and so I left him disappearing far away on the tumultuous surface.

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