MONTHLY WILDLIFE RESEARCH LETTER 
i 
Department of Conservation and Natural History Survey, Cooperating NATURAL HISTORY > 
Glen C. Sanderson and Helen C. Schultz, Editors SEP 18 1975 
-- . IBS ARY 
Urbana, Illinois August, 1975 Vol. 18, No. 8 
Manipulation of Pheasant Habitat R. E. Warner 
Land-use trends on the Sibley Study Area (SSA) sustained the same magnitude 
of corn and soybean farming that has prevailed in east-central Illinois over the 
past several years. Row crop acreages comprised 88.8 percent of the SSA in 1975 
and 89* *1 percent in 1974 (X R 86.0 percent, 1970-75)* Hay acreages were recorded 
at a new low of 1.3 percent (246 acres) of the SSA in 1975> decreasing from 1.5 
percent in 1974 and 2.0 percent in 1973* Small grain acreages comprised 2.5 per¬ 
cent (583 acres) of the SSA in 1975, 1*8 percent in 1974, and 2.5 percent in 1973* 
Land-use patterns on the Ford County Management Unit (FCMU) were similar. 
Hay comprised 1.1 percent (116 acres) of the FCMU in 1975, 1*2 percent in 1974, 
and 2.2 percent in 1973* Small grains declined to 2.8 percent (257 acres) in 
1975> compared with 3*8 percent in 1974 and 3*6 percent in 1973* 
Nest studies conducted in 1975 on the SSA and FCMU revealed a substantial 
* decline in numbers of established and hatched nests per acre in most cover types 
that were searched (see Tables 1 and 2). It was determined that roadsides, small 
grains, hay, pasture, strip cover, and nonagricultural cover on the FCMU yielded 
estimates of 510 hatched nests in 1973, 297 in 1974, and I 65 in 1975. Thus, on 
the FCMU, productivity on these cover types declined 45 percent in 1975, compared 
with 1974. 
Seeded roadside cover on the FCMU in 1975 did not resume the status of 
principal nesting habitat, as evidenced in 1974 and 1973* Roadsides produced 
only 26.1 percent of successful nests in 1975 , diminished from 58.3 percent in 
1974 and 38.8 percent in 1973 (see Table 3)* These data provide clear indication 
that the relative importance of seeded roadsides for nesting has declined on the 
FCMU in I 975 . 
However, in perspective, the densities of hatched nests on FCMU roadsides in 
1975 indicated a relative decline of only 22.0 percent from 1974, whereas the 
densities of hatched nests on SSA unmanaged control roadsides declined 47*1 per¬ 
cent from 1974 (Table 4). 
Understanding the implications of this 1975 decline in roadside nesting with 
respect to future years is difficult. Accurate assessment of any potential 
diversion in preference for roadside cover is made additionally difficult because 
of an increase in early mowing of FCMU roadsides by farmer cooperators. In 1975, 
60 percent of the searched roadside plots were mowed at least once by the time 
the second nest search was conducted (21-31 July), which represents a substantial 
\ increase over the 12 percent and 15 percent of mowed roadside plots in 1974 and 
1973, respectively. Implementation of a continued term of nest studies on the 
FCMU will be carefully considered in view of the 1975 decrease in the establishment 
and success of nests on roadsides. 
