58 
BIRDS OF COLORADO. 
eastern border of Colorado it rarely nests, though still common 
in migration. It is rather late to arrive in the spring and the 
eggs are laid by the middle of June. » 
169. Chen hyperborea. Lesser Snow Goose. 
Migrant and winter resident ; not common. A few are 
seen during migration spring and fall along the plains east of 
the mountains. There is no record of their wintering on the 
plains though probably they are at least an occasional winter 
visitant to the open waters of southeastern Colorado. Twenty 
years ago Henshaw heard of them as wintering abundantly in 
the San Luis Valley. But they are much less common every- 
where in the Rocky Mountain region now than they were then. 
West and southwest of Colorado they still remain fairly abund- 
ant. Breeds far north. 
169a. Chen hyperborea nivalis. Greater Snow Goose. 
Migratory; rare. The eastern form, not coming regularly 
as far west as Colorado, being confined mostly to the Atlantic 
coast. A specimen shot by Pres. Z. X. Snyder east of Greeley, 
March 20, 1895, ^ little longer than the greatest length given 
for the Greater Snow Goose. This is the only certain Colorado 
record. 
171a. Anser albifrons gambcli. American White-fronted 
Goose. 
Migratory; rare. Probably the rarest Goose that regularly 
occurs in Colorado. A few have been taken in migration in 
eastern Colorado. 
172. Branta canadensis. Canada Goose. 
Summer resident, rare except locally; winter resident, not 
common; in migration, common. The most common Goose of 
the State. It might almost be called resident since there is no 
time in the year when there are not some in the State, 
but it is probable that the same individuals do not remain here 
throughout the year, those that breed in Colorado going farther 
south for the winter and their places being taken by those that 
nested further north. On the plains of eastern Colorado they 
are known only as migrants and winter residents. In the 
mountains they breed along the higher secluded lakes at about 
10,000 feet, especially in North Park, where Dr. Cones found 
them breeding in large numbers. (B. N. O. C. II. 1887, 51.) 
A few remain in southern Colorado through the winter and they 
are likely to appear irregularly anywhere east of the range ex- 
cept in the severest weather. 
