BIRDS OF COLORADO. 
53 
130. Merganser serrator. Red-breasted Merganser. 
Winter sojourner, rare; in migration, not micominon. 
Breeds far north. Occurs in winter on the Platte, and in migra- 
tion throughout the plains district of eastern Colorado. Un- 
doubtedly occurs, though not yet reported, on the lower waters 
of western Colorado. 
131. Lophodytes cucullatus. Hooded Merganser. 
Resident; a few remain in the State during the winter, 
and a still smaller number nest irregularly over eastern Colo- 
rado and in the mountains. It is a little more common in 
migration, especially late in the fall, just before the lakes freeze. 
Capt. Thorne found it at Fort Lyon on June 20 and July 2. 
132. Anas boschas. Mallard. 
Resident; in winter, not uncommon; in migration, one of 
the most common ducks, especially in the fall; breeds through- 
out the State below 9,000 feet, on the plains as well as among 
the mountains. Chas. F. Morrison makes the statement that 
in La Plata- County the Mallards are never seen in the fall 
(O. & O. XIII. 1888, 70), however in the lower portions of the 
State they are abundant at that season, and they have been 
known to ascend to 10,500 feet during the autumn. The larger 
part of migration takes place in March, and by the latter part 
of April few are left except those that remain to breed. 
133. Anas obscura. Black Duck. 
Migratory; rare. An eastern species finding in Colorado 
its most western extension. One was taken by C. E. Aiken 
prior to 1873 (Ridgway, Bull. Essex Institute, V. 174), and Prof. 
Wm. Osburn writes that he took one on the Big Thompson, 
near Loveland, March 15, 1889. 
135. Anas strepera. Gadwall. 
Summer resident, not common; in migration, common. 
C. F. Morrison says: “It breeds in the sloughs and small lakes 
at 11,000 feet in southwestern Colorado. I secured ten young 
from the La Plata River, unable to fly. These with the parent 
birds came down from the mountains. They started quite 
young on their southern migration.” (O. & O. XIII. 1888, 145.) 
V. L. Kellogg found them breeding in Estes Park. (Trans. 
Kans. Acad. Science, VII. 1889-90, 86.) Other observers have 
noted their breeding on the plains. It is never as common in 
migration as many of the other ducks, but old hunters expect 
to get a few each season. They are most common during the 
spring migration early in March. 
