16 TH EivA UD US BtOING EU Di heir 
A BIRD CENSUS ON A RESTRICTED SITE 
IN NORTHEASTERN ILLINOIS 
by S.T. DILLON, Biologist, Max McGraw Wildlife Foundation 
This paper summarizes the results of systematic surveys conducted in 1967 
to determine the avian fauna of the Max McGraw Wildlife Foundation. 
Tables are presented listing the total number of individuals of 170 avian 
species seen, together with the monthly percentage of the total. 
The Max McGraw Wildlife Foundation comprises nearly 2,000 acres- 
of land in Kane County, between Elgin and Dundee in Illinois. It lies about 
45 miles northwest of Chicago and approximately 30 miles west of Lake 
Michigan. The habitat of the area is quite varied. The Fox River forms 
the western boundary of the property, with bottomlands consisting of wet- 
land herbaceous plants with a canopy of box elder, willow and ash, among 
others, and a shrub layer of red-osier dogwood and tartarian hoaeysuckle. 
The central unit is made up of upland, hilly terrain with oak, hickory, elm, 
and maple, and a ground cover of grasses and woodland wildflowers. The 
eastern section is formed of level, fertile farmland with row crops being 
prominent, but interspersed with strips of shrub-canopy cover and grain 
game-food plantings. 
Most of the Foundation property is interlaced with roads, with the 
exception of the Fox River bottomlands. As it was necessary to devise 
a census system which would cover a large area in a limited time, a road- 
side transect survey was conceived. The number of miles of roads passable 
by motor vehicle within the central wooded and eastern agricultural units 
was noted and a sample system of roads in each of these two units was 
set up, covering as much of the area as possible. The counts on the central 
unit covered 32 percent of the total roads and on the agricultural area 94 
percent of the total roads. At least two people per vehicle (to verify any 
doubtful count) drove the designated roads on the agricultural and central 
lands at weekly intervals throughout the year. Species were identified and 
the number of individual birds counted as far as the eye could see. The Fox 
River bottomlands were censused entirely on foot, with about 80 percent 
of the acreage being covered. This system worked well for the most part 
except when the heavy and long-lasting snows of January through March 
blocked portions of the road networks and curtailed the counts greatly. 
Our counts have shown that while most species overlap habitat types, 
a few species select a single type and will not be found elsewhere. The 
time at which counts were made influenced results for certain species. For 
example, thousands of bronzed grackles, starlings, redwing blackbirds and 
cowbirds (and, doubtless, rusty and Brewer’s blackbirds as well), in that 
order of abundance, roosted in an overgrown, abandoned nursery area in 
spring and fall. These birds normally were dispersed by the time our 
counts began in the morning, and arrived back at the roost at dusk, after 
our counts were concluded. 
The owl family gave us additional problems. There was evidence that 
many individuals of several species were about, but our methods yielded 
only a few observations. In the warbler and sparrow families, two migratory 
peaks were noted: one in April to May and the other in September to 
October with only a few species observed in the interim. 
We observed major movements of two species of birds. On the after- 
Continued on page 20. 
