Loon

The loon or diver is a type of aquatic bird found in many parts of North America and northern Europe. A loon is the size of a large duck, to which it is unrelated; its plumage is largely grey or black, and it has a spear-shaped bill. The loons compose a genus, family, and order all their own.

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.

Loons swim well, and fly adequately, but are almost hopeless on land, and have difficulty taking off, becoming airborne only after skimming the surface of the water for a couple of hundred meters.

There are five species of loon:

• Great Northern Diver, Gavia immer or Common Loon.
• White-billed Diver, Gavia adamsii or Yellow-billed Loon, which resembles the Common Loon except for its yellow bill.
• Black-throated Diver, Gavia arctica or Arctic Loon.
• Red-throated Diver, Gavia stellata or Red-throated Loon.
• Pacific Diver, Gavia pacifica or Pacific Loon.

The Pacific Loon is often considered to be a subspecies of the Atlantic Black-throated Diver.

top left: Black-throated Diver; bottom left: Red-throated Diver; top right: White-billed Diver; bottom right: Great Northern Diver.
public domain image from a 1905 field guide (http://www.biologie.uni-hamburg.de/b-online/birds/naumann.htm)

The Common Loon is the national bird of Canada and is depicted on the Canadian one-dollar coin, which is therefore nicknamed the loonie.