4 BULLETIN 107, U. S. DEPARTMENT OF AGRICULTURE. 



are the rough-winged swallow, house finch, killdeer, horned lark, 

 Arkansas kingbird, mourning dove, California quail, Bullock's 

 oriole, black-headed grosbeak, cowbird, and yellow-headed blackbird. 



A bird population differing in relative numbers from that of the 

 region just described is found in Davis County, lying to the north of 

 Salt Lake City and extending from the Wasatch Mountains to the 

 Lake. As the area is narrow (at Farmington only about 4 or 5 miles 

 wide), and is bordered on one side by the foothills and on the other 

 by the barren flats of Great Salt Lake, a great variety of bird life 

 may be found on a single farm. The English sparrow is not so 

 plentiful, Brewer's blackbird being the most abundant species, but 

 nearer the Lake the red-wings and yellow-heads vie with it for 

 supremacy in numbers. California gulls sometimes occur in flocks 

 of several hundred, especially where land is being cultivated. Mag- 

 pies also are conspicuous and breed extensively in trees growing 

 along creeks. The other species previously mentioned maintain 

 about the same relative abundance, except that robins, Arkansas 

 kingbirds, and other flycatchers are somewhat more numerous. 



In the valley of the Weber the number of species is more limited, 

 but there is no dearth of individuals. Here, as well as along Chalk 

 Creek, which flows into the Weber, irrigated fields border the river 

 in a long narrow strip, 1 to 2 miles wide. Bird life has segregated 

 itself in these fields, while large numbers of birds which build in the 

 sagebrush of the surrounding hills secure the bulk of food for them- 

 selves and their young in the lower, more fertile, tracts. 



A " bench " lying to the east of this section and at some distance 

 from the river afforded similar conditions and proved a most excel- 

 lent feeding area for a number of more or less desert species dwell- 

 ing on the sides of adjacent hills. Brewer's blackbirds were the most 

 abundant, while along the upper borders of these fields and on the 

 " bench " Brewer's, vesper, chipping, lark, and savannah sparrows 

 appeared in great numbers. The green-tailed towhee, sage thrasher, 

 and mountain bluebird also were present. On the lower fields robins 

 were very numerous and bobolinks not uncommon, but no English 

 sparrows were found. 



The section about Alpine and American Fork, in Utah County, 

 presented an avifauna very similar to that immediately south of 

 Salt Lake City. 



BIRDS FEEDING ON THE WEEVIL. 



The following list includes all of the important bird enemies of 

 the alfalfa weevil. Probably some spring migrants pick up a 

 few while passing and some resident species, whose ordinary habits 

 and food preferences would seem to preclude them from being 

 enemies of the weevil, may occasionally feed on them. In the two 



