Vol. 2*1, No. 3 
Page 3 
Table I. Expected percentage of oaks 
and hickory stumps that will sprout 
after cutting. 
Size class 
(inches) 
Black 
oak 
White 
oak 
Shagbark 
hickory 
2 - 5 
85 
80 
100 
6-11 
65 
50 
90 
12 - 16 
20 
15 
50 
17+ 
5 
0 
25 
Table 2. The number of l/735~acre 
plots required to inventory 
understory stocking. 
Size of forest 
(acres) 
Number of plots 
<10 
25 
10 - 30 
*«0 
30 - 50 
60 
Responses of Prairie Chickens to Habitat Hanipulation- W-66-R R.L, Westemeier, 
J.E. Buhnerkempe 
We see no reason to change our prediction of a decline of at least 32% in 
the number of prairie chicken cocks at Bogota this spring (MWRL 23(12):3). Why 
this decline at a time when recovery in the population, or even a 10-year cyclic 
high (which has currency in Wisconsin) should be evident? The prairie chicken 
population in Marion County (some 80 cocks) will be the highest on record (since 
196*0 and surpass the Bogota flock (Jasper County) for the first time in !*♦ 
years, although sanctuary acreage in Marion County (6*»0 acres) is roughly one- 
half that in Jasper County (1,001 acres). 
Fortunately, pheasants are not yet present in Marion County near Kinmundy 
or Farina. The process of competitive exclusion by pheasants may be the single 
most significant difference among the decimating factors common to both 
populations. 
The number of hatched prairie chicken nests found at Bogota since 1969 was 
negatively correlated with both (1) the percentage of pheasant cocks in the 
combined populations of prairie chickens and pheasants (r ■ -0.757, P_ < 0.01) and 
(2) the number of pheasant cocks (r_ = -0.693, P. < 0.01). The number~of chicken 
nests found was also negatively correlated with the percentage of pheasants in 
the combined populations. These relationships suggest that pheasants may be 
limiting the nesting effort by prairie chickens at Bogota. Actual competition 
between pheasants and chickens for nest sites has not been observed but the 
preceding correlations suggest its occurrence. Twenty instances of nest 
parasitism have been recorded and harassment of chickens on their leks (booming 
grounds) by pheasants has been documented at Bogota. Increased abandonment 
of prairie chicken nests, reduced hatchability of eggs, increased mortality of 
young chickens, and interbreeding are also possible negative interactions 
between the 2 species, but so far, these factors are not well documented as 
being caused by pheasants. 
