Vo 1. 11, No. 10 
Page 3 
5- Responses of P rairie Ch ickens to Habitat Manipu1 at io n R. L. Westemeier 
During the 6 -year period of I 963 - 68 , prairie chicken nests have been verified 
in 11 general cover types on the Bogota Study Area. Nest densities (nests per 100 
acres) averaged 4 .9 in 265 acres of timothy, 6.2 in 732 acres of redtop, 7-9 in 138 
acres of mixed redtop and timothy, 10.3 in 39 acres of weedy grasses and forbs, and 
11.1 in 18 acres of weedy legumes, all of which were systematically searched on foot. 
Although only two nests have been found in 370 acres of mixed wheat stubb1e-1egumes, 
nests commonly are destroyed by spring plowing of this cover type, according to 
local residents. Thus, under present Illinois conditions five or six cover types 
might be considered as preferred nesting cover. 
Since most nests occur within £ mile of booming grounds, a better approach 
to determining nesting preferences is to study nest locations in relation to (1) 
the types of cover available in fields beginning within £ mile of booming grounds 
and (2) the number of hens seen on each respective booming ground. For example, 
a maximum count of 10 hens was made in 1968 on the booming grounds at the center of 
the 140-acre Zimmerman tract. Nest densities (nests per 100 acres) in the cover 
surrounding the Zimmerman booming ground were: redtop, 4.7 (2 nests in 43 acres); 
timothy, 9-1 (2 nests in 22 acres); and weedy grass-forb-legume mixtures, 11.1 (3 
nests in 27 acres). Similar patterns of preference by nesting hens were noted for 
cover near the other three major booming grounds at Bogota in 1 968 . 
Redtop is popularly considered the best type of nesting cover for prairie 
chickens in south-central Illinois, and although the highest density of nests (8 
nests in 19 acres in 1984) so far documented was in redtop with a red clover admix¬ 
ture, the data presented indicate that other types of cover are more readily 
accepted if available. Redtop has the additional disadvantage of being most attrac¬ 
tive to nesting hens only during its second and third growing seasons, after which 
nest densities decline to a low level. 
6. Rabbit Management K. P. Thomas 
Although the primary purpose of night1ighting operations on the Forbes Area 
has been to collect quail, the operation may be of value as an index to trends of 
the population of rabbits on the area. Counts made prior to 1967 were conducted in 
abandoned pastures and fields and ranged from 7*1 rabbits per hour in 1965 to 8.5 
rabbits per hour in I 966 . 
In I 967 and 1968, night1ighting on Zone 1 (sharecrop-burn zone) was limited to 
small-grain stubble fields. In 19&7> 106 rabbits were seen during 8.2 hours of 
night1ighting or 13-0 rabbits per hour; whereas 120 rabbits were observed in 8*92 
hours (13*5 rabbits per hour) during I 968 . Eighty-four acres were covered in 1987 
(1.3 rabbits per acre) and 78 acres in 1 988 (1.6 rabbits per acre). If night1ighting 
can be used as an index to the number of rabbits on the Forbes Area we would expect 
the population to be above that of last year and a harvest approaching 1 rabbit per 
acre on Zone 1. 
