Common Loon
Scientific name: Gavia immer
The eerie calls of common loons echo across clear lakes of the northern wilderness. Summer adults are regally patterned in black and white. In winter, they are plain gray above and white below, and you’ll find them close to shore on most seacoasts and a good many inland reservoirs and lakes. Common loons are powerful, agile divers that catch small fish in fast underwater chases. They are less suited to land, and typically come ashore only to nest.
Weight
88.2-215.2 ounces
Length
26.0-35.8 inches
Diet
Common loons are expert anglers. Their diet consists of mostly fish, particularly perch and sunfish on their northern lakes. If fish are scarce or water is too murky for fishing, they will catch crustaceans, snails, leeches and even aquatic insect larvae.
Loons shoot through the water like a torpedo, propelled by powerful thrusts of feet located near the rear of their body. When their quarry changes direction, loons can execute an abrupt flip-turn, turning 180 degrees in a fraction of a second.
Habitat
Common loons are a classic bird of the North Woods lakes. They are excellent indicators of water quality as they require crystal-clear lakes (which makes it easier for them to see prey underwater) with abundant populations of small fish. Lakes with coves and islands are preferred as they provide cover from predators while resting and nesting. They also require lakes with enough surface area for their flapping-and-running takeoffs across the water. In their winter range along ocean coasts, they occur fairly close to shore and in bays and estuaries. They are only rarely found more than several miles offshore. Some common loons winter inland, on large reservoirs and slow-moving rivers. Common loons that migrate across interior North America find large lakes and rivers to move between on their way north and south.
Migration
Our lakes in Lewisboro are not far enough north to be within the breeding grounds of the common loon. However, we are well within their migration routes as common loons migrate from northern lakes in Canada and the very northern part of New York state to coastal ocean waters – from Canada to the Atlantic coast.
Did You Know?
Loons are like airplanes in that they need a runway for takeoff. In the case of loons, they 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.
Common Loon breeding; Photo: Brian Collins
Adult with chick; Photo: Brian Lasenby
Juvenile Common Loon; Photo: Rick and Nora Bowers
Splashing about; Photo: Jeff Nadler
More on Birds in Lewisboro