[530] BIRDS OF OREGON 



April 2.1, Umatilla County) and remains until September (latest date, 

 September 2.8, Klamath County). During May and June, it is usually 

 seen in small groups of two or three birds, but later in the year it mingles 

 with the summer and fall flocks of blackbirds. In these great swarms it 

 is far outnumbered by the Yellow-heads, Red-wings, or Brewer's Black- 

 birds. It is difficult to distinguish it in these mixed flocks, and conse- 

 quently fall records are comparatively scarce. 



In western Oregon, it can be considered as only a straggler. Bretherton 

 reported it from Newport, March 19, 1897, in manuscript, to the Bio- 

 logical Survey, and Overton Dowell, Jr., twice took specimens at Mercer 

 Lake in western Lane County (August 18, 192.5, and July 5, 1930). 



Little has been written regarding this species as an Oregon bird. It 

 seems to have been entirely overlooked by the earlier naturalists, or 

 perhaps it has become more abundant in recent years. It was first re- 

 corded from the State by Woodcock (1901), who listed it from Baker 

 County. Miller (1904) found it in Wheeler County. Jewett (1909^ 

 included it in his list of Baker County birds. Peck (191 la) reported it in 

 his notes on the northern part of Malheur County. Walker (1917^) 

 found young at the mouth of the Deschutes River, July 2.8, 1914. Willett 

 (1919) recorded it as a breeding species at Malheur Lake, and Dickey and 

 Van Rossem (192.2^) also noted it as a Harney County bird. The manu- 

 script records of the Biological Survey contain many notes by Preble, 

 Bailey, Streator, and others giving it as an uncommon, common, and at 

 times even abundant, summer resident of the three southeastern counties, 

 Malheur, Harney, and Lake. Our own notes also indicate that these 

 three and Klamath are the Oregon counties favored by this bird. 



Much has been written about the parasitic habits of the cowbird. The 

 lady of the species has certainly solved the question of raising a family 

 with the least possible trouble to herself by the simple expedient of 

 laying the egg or eggs in the nest of some other small bird. As the cow- 

 bird's eggs hatch in 10 days, the shortest incubation period of any of our 

 common passerine birds, the young birds usually have one or more day's 

 start on the legitimate nestlings in competition for the food brought by 

 the parent birds. Friedmann (1919) published a very exhaustive study of 

 the cowbird group, in the course of which he listed 195 species of birds 

 as victimized by Molothrus ater in its various forms. These victims 

 naturally cover a wide diversity of groups, but sparrows, warblers, vireos, 

 and blackbirds are those most commonly imposed upon. Little has been 

 learned regarding the species parasitized in Oregon, owing to lack of 

 resident ornithologists in the territory that the cowbird frequents. Jewett 

 has records of three Nevada Savannah Sparrows' nests at Malheur Lake, 

 each of which contained one cowbird's egg. These are our only definite 

 notes. 



