200 
as many as the areas of human neighborhood. Their total of some 200 
acres is, however, rather small for any definite inference. 
Tue Birp Lire or ILLINOIS PASTURES 
On the 3796 acres of pasture whose bird population was accurately 
ascertained in the two summers, an average of 1068 birds to the square 
mile was found—1041 in northern, 1274 in central, and 937 in southern 
Illinois. If we separate the data for the different years, we find an 
average for the state of 881 to the square mile in 1907 and 1194 to the 
mile in 1909, the excess for the latter year being 36 per cent. in northern 
Illinois, 29 per cent. in central Illinois, and 30 per cent, in southern. 
The 6335 birds identified in pastures belonged to ninety-six species, 
but 85 per cent. of these belonged to twenty-three species, leaving but 
15 per cent. for the other seventy-three. There was thus no small dis- 
tinctive group of pasture birds, such as were found in some other habi- 
tats, but the pasture was merely one of the preferred resorts of a 
rather long list of species, every one of which was, in fact, found in 
one or more other situations more frequently than there. 
The English sparrow stood at the head of the list of pasture visitants, 
but the meadowlark led the native birds in each year and in each section 
of the state, and was found in southern Illinois pastures more than 
twice as common as the sparrow. The crow-blackbird, or bronzed 
grackle, was third in order of numbers in both years and in the whole 
state, but it was surpassed in the southern part of the state by the field 
sparrow and the mourning dove, and in central Illinois by the cowbird. 
Among other more prominent birds were the flicker (which was, how- 
ever, only about a third as common in southern Illinois pastures as 
farther north), the robin, also much the least abundant in southern 
pastures, the prairie horned lark, much the commonest in northern IIli- 
nois, and the red-winged blackbird. 
Comparing the data of the two years, we find 13 of the 23 most 
abundant species represented by notably larger numbers per square mile 
in 1909 than in 1907, two of them by fewer, and 8 by virtually equal 
numbers. The group of pasture birds thus gives the same indication 
of increased numbers in 1909 as do the combined data from all situa- 
tions. Additional particulars concerning these species may be gathered 
from the following table. 
From the known food habits of the more abundant pasture species 
it appears that the meadowlark and the crow-blackbird are the kinds 
most serviceable, under ordinary conditions, as a pasture police for the 
control of injurious insects. When a considerable outbreak of a destruc- 
tive species occurs, many other birds attracted by unusual chances for 
“loot” will come to the aid of the regular force; but it is to the less 
conspicuous services of constant residents and frequent visitants that 
the farmer must look for a steady pressure upon the multiplication 
SS 
