Birds of Zion National Park

The Great Northern Loon (Gavia immer), is a large member of the loon, or diver, family of birds. The species is known as the Common Loon in North America and the Great Northern Diver in Eurasia; its current name is a compromise proposed by the International Ornithological Committee.
The European name "diver" comes from the bird's habit of catching fish by swimming calmly along the surface and then abruptly plunging into the water. The North American name "loon" is a reference to the bird's clumsiness on land, and is derived from Scandinavian words for lame, such as Icelandic "lúinn" and Swedish "lam". Having large webbed feet, the loons are efficient predators, powerful swimmers, and adroit divers.
In summer, Common Loons breed in large lakes either on the tundra or in evergreen forests. During the winter, Common Loons are found along the coast in near-shore waters and on large bays and reservoirs. On migration, this species may be found on large bodies of freshwater in the interior. Common Loons primarily eat small fish, which they catch by diving. In appropriate habitats in summer, Common Loons may be seen nesting on small islands in lakes or directly on the lake shore. At this time of the year, birdwatchers may hear this species’ haunting “yodeling” calls on calm nights. During the winter, Common Loons are most easily observed out at sea through binoculars or spotting scopes, and may be seen floating low in the water, diving below the surface in pursuit of prey, or flying awkwardly close to the tops of the waves. This species is primarily active during the day, but calls at night during the breeding season.
The bird needs a long distance to gain momentum for take-off, and is ungainly on landing. Its clumsiness on land is due to the legs being positioned at the rear of the body: this is ideal for diving but not well-suited for walking. When the birds land on water, they skim along on their bellies to slow down, rather than on their feet, as these are set too far back. The loon swims gracefully on the surface, dives as well as any flying bird, and flies competently for hundreds of kilometers in migration. It flies with its neck outstretched, usually calling a particular tremolo that can be used to identify a flying loon. Its flying speed is about 120 km/h (75 mph) during migration.[8] Its call has been alternately called "haunting," "beautiful," "thrilling," "mystical", and "enchanting."[10][11]
Great Northern Loon nests are usually placed on islands, where ground-based predators cannot normally access them. However, eggs and nestlings have been taken by gulls, corvids, raccoons, skunks, minks, foxes, snapping turtles, and large fish. Adults are not regularly preyed upon, but have been taken by sea otters (when wintering) and Bald Eagles.[12] less ↑