Common Loon: Diver Down!

Common Loons by Brian Lasenby, Shutterstock


Common Loons (called “divers” throughout Europe) are avian torpedoes, perfectly designed for underwater pursuit of their fish prey. Unlike most birds, the Common Loon, Yellow-billed Loon, and others in their family have solid bones, which help them sink quickly and silently beneath the surface. Strong webbed feet propel them through the water to depths of up to 150 feet.


Loon legs are placed far back on their bodies for more efficient swimming. (Flip side: They can barely walk on land and often get into trouble when they mistake icy pavement for water.) Loons can expel air from their lungs and flatten their feathers to dive and swim even more efficiently. Once below the surface, the loon’s heart slows down to conserve oxygen.


Although the Common Loon population appears to be increasing, threats still exist. Among these are lead poisoning: the birds ingest discarded lead fishing tackle as they scoop up pebbles from the lake bottom to store in their gizzards. In the Adirondacks, acidification and contamination of lakes caused by burning of fossil fuels also pose a problem. Common Loons are accidentally caught by commercial fishing nets, both on the Great Lakes and in the ocean.



ABC is actively working to counter many of these threats to ensure a future for the Common Loon and other waterbirds.


Loons, like airplanes, need a runway for takeoff. These large, heavy birds require water “runways” from 30 yards up to a quarter-mile, depending on the wind, to get up enough speed for lift-off. Once aloft, loons are strong and direct fliers, reaching speeds of up to 70 miles per hour during their short-distance migrations.


Loons in flight are quite a spectacle, says ABC Conservation Biologist Dan Lebbin. “I have seen hundreds of loons flying overhead, migrating south on frigidly cold days from the shores of Cayuga Lake in New York,” he says. “The birds were coming off the Great Lakes and passing over the Finger Lakes on their way to the coast, a couple hours into their flight.”


Common Loons require clear, unpolluted lakes with abundant populations of small fish to breed successfully. They prefer the quiet atmosphere of uninhabited lakes; human disturbances such as canoeing, camping, fishing, and motor boating in these places can lower the loon's reproductive success. The association with northern lakes makes them among the best known of birds, with countless movie soundtracks using their haunting nocturnal wails, yodels, and tremolos to evoke a picture of remote wilderness and dark conifer forests.