Vo I. 12, No. 1 
Page 2 
counts showed an even greater difference--routes run on the Ford County Management 
Unit showed about three times the number of broods as on the Sibley Study Area. 
3* Factors Inf1uencinq Distribution and Abundance of Pheasants 
W. L. Anderson, 
D. R. Vance 
It was reported in the preceding research letter (MWRL 11 (12):2) that samples of 
grit and pheasant tissues from Sibley (good pheasant range) and from Neoga (poor 
range) have been analyzed for concentrations of 62 chemical elements. For grit, 
statistical analyses of the data reveal that mean concent rations of nine elements 
exhibit significant differences, Neoga compared with Sibley. Of these, two (potassium 
and sodium) were less abundant, and seven (barium, cobalt, iron, gallium, lanthanum, 
manganese, and nickel) more abundant, in Neoga grit than in Sibley grit. As it is 
reasonably well established that grit is a major source of minerals for pheasants, 
these findings indicate that the mineral intake by birds in good range and in poor 
range probably differs appreciably. It is especially noteworthy that, in grit from 
Neoga, the number of elements present in potentially excessive quantities is con¬ 
siderably greater than the number present in potentially deficient amounts. 
4. Respo nses of Bobwhites to Habitat Manipulation J. Ellis, P. Matthews 
Results of the prehunt censuses conducted on the Dale and Forbes areas during 
early November 1968 revealed the highest quail population densities since the initia¬ 
tion of this study. On Dale, 27 coveys with 485 quail (44 birds per 100 acres) were 
located. This prehunt population in 1968 represented an increase of 21 percent over 
the prehunt population in I 967 (36 birds per 100 acres). On Forbes, 535 quail in 35 
coveys (23 birds per 100 acres) were located, an increase in population density of 
only 2 percent from 1 967 to I 968 . 
Quail density on the experimental management zone on the Dale Area increased 30 
?oAQ ent fr ° m the leVe * ' n 52 btrds P er 100 acres to 67 quail per 100 acres in 
1968. The only management technique used in this zone on the Dale Area was prescribed 
burning. On Forbes in 1 967 and I 968 , the population density on the experimental 
management zone remained at 95 birds per 100 acres. 
5* Responses o_f Prairie Chickens to Habitat Manipulation R. L. Westemeier 
During the 6-year period of 1 963-68 at Bogota, data have accumulated which indi¬ 
cate the limitations in spacing that nesting prairie chickens will tolerate. Measure¬ 
ment of distances between 65 nests and their nearest neighboring nests in contiguous 
nesting cover revealed a median distance of 107 yards. The minimum distance of 17 
yards between nests involved one nest destroyed by predation and one hatched nest, 
which may represent the effort of a single hen. Although two hatched nests were 
found (July 5, I 963 ) as close as 30 yards, these nests may not have been active 
simultaneously. 
A tolerance limit of approximately 120 yards was suggested by plotting the 65 
distances in relation to hatching success. Considering only the hatched nests and 
the nests destroyed by predation, 44 percent of 34 nests located closer together than 
20 yards were lost to predation, whereas 16 percent of 31 nests located over 120 
yards apart were destroyed by predators. Seventy-five percent of all predation 
occurred when inter-nest spacing was less than 120 yards. Further, five lone nests 
in isolated fields of nesting cover successfully hatched; many such "no-neighbor" 
nests at Bogota have been destroyed by farming activities but none have been verified 
