THE BIRD BOOK 
FALCONS AND CARACARAS 
Family FALCONDIDAE 
353. White Gyrfalcon. Falco islandus. 
Range. — Arctic regions; south in winter cas- 
ually to northern United States, chiefly on the 
coast. 
Gyrfalcons are large, strong, active and fear- 
Gray Gyrfalcon 
White Gyrfalcon 
Buff 
less birds, about 23 inches in length. Their food consists chiefly of hares, 
Ducks and Waders which abound in the far north. The present species is 
snowy white, more or less barred with blackish brown on the back and wings 
and with a few marks on the breast. They nest upon the ledges of high cliffs, 
laying three or four eggs of a huffy color, blotched and finely specked with 
reddish brown, this color often concealing the ground color. Size of eggs, 2.30 x 
1.80. In America, they nest in Greenland and the Arctic regions. 
354. Gray Gyrfalcon. Falco rusticolus rusticolus. 
Range. — Arctic regions ; south in 
winter to northern United States. 
This species is of the size of the last 
but the plumage is largely gray, bar- 
red with dusky. They nest more 
abundantly in southern Greenland than 
do the preceding species. The nesting 
habits and eggs do not differ. 
354a. Gyrfalcon. 
Falco rusticolus gyrfalco. 
Range. — Arctic regions; south cas- 
ually to Long Island. 
This sub-species is hardly to be dis- 
tinguished from the preceding; its 
nesting habits and eggs are identical, 
the nests being of sticks, lined with weeds 
most inaccessible ledges of cliffs. 
Buff 
and feathers and placed upon the 
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