420 
‘ 
NUMBERS OF THE More ABUNDANT SPECIES, HARVEY TO 
Grant Park, Marcu 26 To 28, 1907 
Ratio to total 
No. of each ING! 
Lapland longspur 182 32% 
English sparrow | 67 12 
Meadowlark { 51 | 9 
Prairie horned lark | 46 
Wilson’s snipe i 45 9 
Canada goose 32 6 
Rusty blackbird 32 6 
Bronzed grackle 14 2 
Prairie hen 13 2 
All birds, 1061 to the square mile. 
In the central Illinois division, (March 29 to April 5) the number 
of birds to the square mile (719) was only 70 per cent that in the north- 
ern division, although the number of spécies was more than twice as 
large (54 for central and 24 for northern). Of winter residents there 
still remained the Lapland longspur, tree sparrow, junco, and golden- 
crowned kinglet, which taken together made less than 10 per cent of 
the birds of the area. The summer birds had already come to predomi- 
nate in this transition period, and the total number. of birds per square 
mile recorded on this central Illinois trip (719) was much above the 
average of this region for the winter season, (440), and greater even 
than the July average (650) of the same year. If, however, we take 
into consideration the permanent and summer residents only, we see 
that the summer population had not yet arrived in full strength, the 
total number averaging only 445 to the square mile. The crest of the 
spring wave already referred to was thus made up of all four of the 
residence classes in the ratio of 23% of permanent residents, 9% of 
winter residents, 30% of migrants and 38% of summer residents. If 
we omit the English sparrows, the corresponding residence ratios are 
permanent 17%, winter 10%, summer 41%, and migrant 33%. 
RESIDENCE CLASSIFICATION, CENTRAL ILLINOIS, SPRING, MArcH 
29—Aprin 5, WATSEKA TO FLAT Rock, EASTERN 
Ittinois (CENTRAL) 
NUMBERS AND PER CENTS OF SPECIES 
Permanent Winter Summer Migrants All 
Numbers 19 4 20 alpl 54 
Per cent. 35.2 7.4 37.0 20.4 100 
NUMBERS AND PER CENTS OF ALL BIRDS 
Numbers 289 115 489 392 1294 Ve 
Per cent. 23.0 8.9 37.8 30.3 100 " 
