?6 
BIRDS OF COLORADO. 
the mountains to ii,ooo feet. The nest is repaired for the 
season about the first of March, and the young are hatched about 
three months later. 
352. Haliaeetus leucocephalus. Bald Eagle. 
Resident; fairly common. Mostly in the mountains in the 
summer time and on the plains during the winter. Breeds in 
the mountains to 9,000 feet and occasionally higher; breeds less 
commonly on the plains. Capt. Thorne found a nest with two 
young, June 12, near Fort Lyon on the Arkansas River. 
355. Falco mexicanus. Prairie Falcon. 
Resident ; not uncommon. Breeds from the plains to 
10.000 feet. In some of the more open portions of western Colo- 
rado it is quite numerous. Nearly all leave the State in the 
winter, returning in March and April. The eggs are laid in 
]\Iay. 
356. Falco peregrinus anatum. Duck Hawk. 
Resident; not uncommon, locally. Has been reported 
from many places in the State. W. P. Lowe found the nest and 
young in St. Charles Canon, near Pueblo, during the summer 
of 1895. Dennis Gale took a set of eggs on the Poudre River, 
April 30, 1889. Others report it as breeding up to 10,000 feet 
in the mountains. 
357. Falco columbarius. Pigeon Hawk. 
Summer resident ; rather uncommon ; in migration fairly 
common ; a few remain through the winter in the lower por- 
tions. The eggs have been taken in various parts of the State, 
from the plains to about 9,000 feet, but more commonly from 
8.000 to 9,000. Eggs are laid about the first of June. 
358. Falco richardsonii. Richardson’s Merlin. 
Summer resident; rare; in migration not uncommon. 
There are several references to its breeding in the State, as it 
undoubtedly does, but this seems to have been inferred from its 
being seen here in summer rather than from its nest and eggs 
having been actually taken. Drew states that it breeds from 
the plains upward. It has been taken in summer as high as 
11.000 feet. In migration occurs throughout the State. 
360. Falco sparverius. American Sparrow Hawk. 
Resident; abundant. The most common hawk from the 
plains to 11,000 feet. In mild winters, like that of 1895-6, 
quite a number remain throughout the lower portions of the 
state, but the bulk winter farther south, returning early in 
March. Eggs are laid the latter part of April and fully fledged 
