Loons swim well, and fly adequately (their bones are much denser than those of most birds), but are almost hopeless on land. The larger loons have difficulty taking off, becoming airborne only after skimming the surface of the water for a couple of hundred meters; some observers state that they are scarcely any better at landing. Because these birds locate their prey underwater mainly by sight, they prefer lakes with clear water.
Loons breed on inland freshwater lakes and ponds, but move to the coasts in winter, and often move much further south. The nest is usually a mound of plant material close to water. A pair may mate for life, although this fact has been questioned recently. Loons can live as long as 30 years.
The genus name Gavia is Latin for "Smew", even though loons are not smews.
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 comes from the bird's haunting, yodeling cry, a symbol of the Canadian wilds.
Red-throated Diver or Red-throated Loon, Gavia stellata.
Black-throated Diver or Arctic Loon, Gavia arctica.
Pacific Diver or Pacific Loon, Gavia pacifica (treated by some authorities as a subspecies of G. arctica).
Great Northern Diver or Common Loon, Gavia immer.
White-billed Diver or Yellow-billed Loon, Gavia adamsii.
