1913] 
Cahn: Birds of Waukesha County 
127 
Buteo platyp terns (Vieillot). Broad-Winged Hawk 
A common migrant found often early in April. Apparently a 
perfectly harmless hawk, which, in this region, feeds largely upon 
frogs and field mice ( Microtus pennsylvanicus) . 
Archibuteo lagopus sancti-johannis (Gmelin). Rough-Legged 
Hawk 
A regular migrant and occasionally a winter resident, and never 
a very common species. Three were seen over Oconomowoc Lake 
on April 16, 1911, and one late in September, 1912. 
Haliaeetus leucocephalus leucocephalus (Linnaeus) . Bald Eagle 
A single immature individual seen in a dead tree near Dutch- 
man’s Lake on September 8, 1912, is the only record during the 
last few years for this bird. This individual was not timid, and 
was closely observed by five persons. 
Falco columbarius columbarius Linnaeus. Pigeon Hawk 
A common migrant, arriving early in April. 
Falco sparverius sparverius Linnaeus. Sparrow Hawk 
A summer resident, though not a very common one. A pair 
nested in 1912 near Pine Lake, but the nest was robbed before the 
young hatched. Several nests were found near Golden Lake in 
1913. 
Pandion haliaetus carolinensis (Gmelin). Osprey 
An occasional visitor within the county during the summer, 
but not resident so far as is known. On August 16, 1912, a pair 
fished along the north shore of Oconomowoc Lake, feeding on the 
small fish found just beneath the surface of the water. 
Asio wilsonianus (Lesson). Long-Eared Owl 
A common resident and breeding species in many of the wilder 
regions. In 1912 a pair bred in the thick swamp area at the 
south side of Dutchman’s Lake, and another pair nested just 
north of Ashippun Lake. A lone individual, besieged by an army 
of over one hundred bronzed grackles and several blue jays, was 
found near the west end of Oconomowoc Lake on October 3, 1913. 
Asio flammeus (Pontoppidan) . Short-Eared Owl 
A common migrant and winter resident, and on one occasion at 
least a summer resident, though so far as known not a breeding 
