Common Loon Gavia immer
- Length: 24 inches Wingspan: 58 inches
- Sexes similar
- Large diving bird with long body that rides low in the water
- Large bill is straight, tapers to a point, and is held horizontally
- Feet set far back on body, and trail behind body in flight
- Upperwings wholly dark in flight
- Black bill
- Black head
- Black neck with white markings
- White chest and belly
- Black back with white checkering and spotting
- Pale gray bill
- Gray-brown cap, forehead, nape, hindneck and back
- White face, eye ring, chin, throat, foreneck and belly
- Jagged border between white foreneck and dark hindneck
- Like basic-plumaged adult but often with paler bill and white scalloping
Cormorants have hooked bills. Western, Clark's and Red-necked Grebes have
thinner bills marked with yellow and show white in the wings in flight.
Red-throated Loon has a thinner, upturned bill that it carries above horizontal.
In basic and immature plumages its back is spangled with white spots and its
head and neck are pale gray, with a straighter line of division with the white foreneck. Pacific Loon has a shorter, thinner bill, a sharp line dividing the
pale foreneck and dark hindneck and no white around the eye. The rare
Yellow-billed Loon is similar in all plumages, but has a bill that is beveled
upwards at the tip and a blockier head, and is entirely yellow beyond the gonys.
In basic and immature plumages, the head and hindneck are paler with a darker
spot to the auriculars, and back has more pattern.
Length and wingspan from: Robbins, C.S., Bruun, B., Zim, H.S., (1966). Birds
of North America. New York: Western Publishing Company, Inc.
Above information used courtesy of
United States Geological Survey.