Identification of Native North American Species of Swans and February Bird of the Month PART 1 4CBC...

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Identification of Native North American Species of Swans

and February Bird of the MonthPART 1

4CBC 14 February 2012

Tim Reeves

Photographs by Tim Reeves and from Birds of North America Online and from

Bill Schmoker online

February 2012 Bird of the Month

February 2012 Bird of the Month

Swan at Lake Luther 4 Feb 2012

February 2012 Bird of the Month

February 2012 Bird of the Month

February 2012 Bird of the Month

February 2012 Bird of the Month

February 2012 Bird of the Month

February 2012 Bird of the Month

Reference Photos from BNA online of the 2 Swan Species Native to North America

Trumpeter Swan & Tundra Swan

Trumpeter Swan

• Forehead feathers come to point at junction with bill

• Broad, triangular black patch of black skin goes to and around eye

• Often has rusty head and neck due to time spent in ferrous waters.

• Line of black facial skin dropping from eye to base of bill uniformly gently curved.

Trumpeter Swan• Forehead feathers come

to point at junction with bill

• Broad, triangular black patch of black skin goes to and around eye

• Often has rusty head and neck due to time spent in ferrous waters

• Line of black facial skin dropping from eye to base of bill uniformly gently curved

• Forehead slopes straight into the straight culmen = upper edge of upper mandible

Trumpeter Swan• Forehead feathers come

to point at junction with bill

• Broad, triangular black patch of black skin goes to and around eye

• Often body, neck, and head pure white

• Line of black facial skin dropping from eye to base of bill uniformly gently curved

• Back uniformly gently rounded

Trumpeter Swan• Forehead slopes

straight down into straight culmen

• Often head and neck rusty from time spent in ferrous waters

• Line of black facial skin dropping from eye to base of bill uniformly gently curved

• Back uniformly gently rounded

Trumpeter Swan• Freshly fledged young

have pink bills but always with a black base

• Young are uniformly intermediate – darkish gray

• Adult shows most characters already noted

Trumpeter Swan• Juveniles throughout

winter have black bills with some dark red on culmen

• Juveniles are darker than young fledglings

• Juvenile forehead drops straight down straight culmen just like adult

• Adults show most characters already noted

Now Switching to Tundra Swan

• Much smaller bird than Trumpeter Swan but definitely size difference best observed when both species are observed together

• Shorter neck than Trumpeter Swan

• Smaller bill that is concave on culmen, not straight

• Much less likely to have rusty head and neck

Tundra Swan• Adults with concave

culmen = upper edge of upper mandible

• Most birds have yellow spot on lore; spot size varies greatly and is sometimes lacking

• Neck shorter than Trumpeter Swan

Tundra Swan• Narrow, straight-edged

black facial skin to eye which isolates the larger eye

• Line from eye not uniformly gently curved to bill base. Often bulge or notch at edge near bill base

• Back somewhat more highly humped than in Trumpeter Swan

Tundra Swan• Narrow, straight-

edged black facial skin to eye

• Line from eye not uniformly gently curved to bill base.

• Back somewhat more highly humped than in Trumpeter Swan

Tundra Swan• December juveniles

not uniformly darkish gray; pale on lower neck and breast and belly and irregularly on back

• Left bird still showing some faint color in dark bill

Tundra Swan• Adult forehead

feathers rounded at junction with bill

• Usually yellow lore• Eye looks isolated,

being larger than the narrow yellow/black skin path to eye from bill

• Crown rounded, not dropping straight into the somewhat concave culmen

Tundra Swan• Recently fledged

young are pale gray• They have pink bills

which are not black at the base

• The eye is completely isolated from bill

• The adult shows the narrow straight edged black skin extending to the eye

Now back to our Bird of the Month

• I photographed these 6 swans at Lake Luther during the Farmington Christmas Bird Count on 17 December 2011.

• All birds were the same size as the two original groups of 3 joined each other

• 1 family with one juvenile was present

• 3 other adults formed the other group, all birds with rusty heads