Yi Uu». 
MONTHLY WILDLIFE RESEARCH LETTER 
Department of Conservation and Natural History Survey, Cooperating 
Glen C. Sanderson and Helen C- Schultz, Editors 
Urbana, Illinois 
September, I 974 
Vo 1. 17, No. 9 
Manipulation of Pheasant Habitat 
G. B. Joselyn 
There are indications of a rather substantial decline in pheasant population 
levels on the Sibley study area (SSA) and on the Ford County Management Unit 
(FCMU), compared with 1973- Based on tentative calculations, the decline appears 
to be in the range of 40 to 50 percent. 
Aberrant weather conditions last spring (wet) and during July (dry) make an 
accurate assessment difficult, but the data seem to show the following: 
1. Breeding populations on both areas this past spring were about 20 percent 
below those of 1973 . 
2. August brood counts on both areas showed rather sharp declines in total 
numbers of broods observed, and, particularly on the SSA, an unusually low pro¬ 
portion of hens with broods (34 percent). 
3. Tentative calculations from simultaneous nest studies carried out last 
summer on the FCMU and SSA show that productivity on the FCMU declined over 40 
percent from 1973 (510 to 297 successful nests); no comparative data were 
available from the SSA for 1973 but a similar decline in productivity is sus¬ 
pected for that area. 
On the SSA, the decline in numbers of broods observed during early-morning 
counts in August approached 70 percent (29 broods per 100 miles in 1973, 9 broods 
per 100 miles in 1974); on the FCMU, the decline was 43 percent (56 broods per 
100 mi les in 1973; 32 per 100 miles in 197*0* The proportion of hens observed 
with broods on the SSA in August (34 percent) was the lowest of the past 13 years 
(1962-73 average was 74 percent); the corresponding figure on the FCMU, 69 
percent, was near the 8 -year average. The decline can be attributed in part to 
conditions that made observations difficult, as half the mornings in August on 
w ich brood counts were made had little or no dew, an extremely unusual circum¬ 
stance for that time of summer. 
Hence, we conclude at this time that the decline in pheasant numbers in 
late summer, I 973 to 1974, on the two areas is 40 to 50 percent and that the 
issimilar figures shown by the nest studies and brood counts can be largely 
explained by the unusually poor conditions for observation of broods in August. 
Bill Preno and 
mile throughout the 
Jack Ellis calculate 
prime pheasant range 
40 to 50 percent fewer young 
this year compared with late 
per square 
summer 1973 , 
NATURAL HISTORY SURVEY 
