1913] 
Cahn: Birds of Waukesha County 
117 
Mergus serrator Linnaeus. Red-Breasted Merganser 
A regular migrant on the larger lakes. Found usually in larger 
flocks than the preceding, but the flocks are fewer in number. 
Arrives in the spring about the same time as Mergus americanus , 
but leaves earlier in the fall. 
Lophodytes cucullatus (Linnaeus). Hooded Merganser 
A common migrant, coming somewhat later than the preceding 
species. None of the Mergansers nest within the county. 
Anas platyrhynchos Linnaeus. Mallard 
A common migrant and winter resident, and regular, though 
not a common, summer resident and breeding species. Several 
pair nest annually in the “dead river” area of the Oconomowoc 
River, and in the wet marshes about Ashippun Lake. These are, 
however, promptly exterminated on the first day of the hunting 
season. 
Anas rubripes Brewster. Black Duck 
A common migrant and often a winter resident. During the 
winter they may sometimes be found in the grain fields several 
miles from open water. Apparently far less abundant than 
formerly, although one of our most timid ducks. 
Mareca americana (Gmelin). Bald pate 
A common migrant, more common in the spring than in the 
fall, and usually on the larger lakes. Found generally in small 
flocks or pairs, associated with other ducks, often with the Lesser 
Scaup and Ring-neck. 
Nettion carolinense (Gmelin). Green-Winged Teal 
A common migrant during late March and April. One of the 
common ducks of the region, although steadily decreasing in 
abundance. 
Querquedula discors (Linnaeus). Blue-Winged Teal 
A regular and common migrant, far more abundant than the 
preceding species. Steadily decreasing in numbers, and is 
at present more uncommon than a few years ago. Arrives about 
the second week in April, and may be seen until well into May. 
The fall migration begins early — about the last of September, and 
is of very short duration. 
