MONTHLY VJIIDUFE RESEARCH LETTER 
Department of Conservation and Natural History Survey, Cooperating 
T. G. Scott, Editor 
Urbana, Illinois 
September 1958 
Vol. 1, No. 9 
W-30-R-12 R. F. Labisky 
Field investigations of the reproductive ecology of pheasants on the 
intensively cultivated Sibley area in 1958 were completed on September 25. The 
100, randomized, 10-acre, study plots, representing a b.3 per cent sample of the 
23,200-acre study area, that were searched for nests in 1957 were again searched 
in 1958. The nest searching in 1958 yielded 266 nests, or lib.5 per cent more 
than were located during the 1957 nesting season when only 12U nests were found. 
Comparisons of establishment and success of pheasant nests as related to cover 
types for the 1957 and 1958 nesting seasons are summarized by percentage in the 
following table. Sample sizes are shown in parentheses. 
1957 
1958 
Cover Types 
Nests 
Established 
Nests 
Successful 
Nests 
Established 
Nests 
Successful 
Row Crops 
0.0 (0) 
0.0 (0) 
0.0 (0) 
0.0 (0) 
Small Grains 
16.1 (20) 
55.0 (11) 
7.9 (21) 
38.1 (8) 
Hayfields (Tame) 
U6.8 (58) 
32.8 (19) 
69.9 (186) 
31.2 (58) 
Pastures (Tame and Wild) 
2b.2 (30) 
16.7 (5) 
b.l (11) 
63.6 (7) 
Strip-Cover 
12.1 (15) 
bO.O (6) 
15.8 (b2) 
12.0 (5) 
Non-Agricultural 
0.8 (1) 
100.0 (1) 
2.3 (6) 
33.3 (2) 
Totals or Means 
100.0 (12b) 
33.9+8.b*(b2) 
100.0 ( 266 ) 
30.8+5.5 
(80) 
-^■Fiducial - limit s at 0705 level. 
W-b2-R-8 R. D. Lord 
The September sample of rabbits showed a prevalence of pregnancy of 0.29 
which was bl per cent higher than that of last year. The average litter size was 
5.00, the same as that for last year. 
OCT 9 1959 
NATURAL 
HISTORY SURVEY 
LIBRARY 
