Vol. 9, No. 12 
Page 3 
three grounds were 31, 54, 83, 58, 50, and 39* The high count of 83 chickens was 
made on October 20. It was difficult to distinguish the sexes because of the 
halfhearted nature of booming in fall and the incomplete development of plumage. 
However, most of the birds involved in the high count of 83 were believed to be 
cocks. Th-s is encouraging because the high count during the spring of 1966 was 
4l cocks. Theoretically, therefore, the Bogota population could sustain a winter 
mortality as high as 50 percent and still maintain a breeding population in l 967 
equal to that of I 966 . 
Supplemental to the booming ground counts were several reports received from 
local farmers regarding prairie chicken flocks numbering as high as 80 birds in 
the fall of 1986 . Also, counts of this magnitude were reported to be more numerous 
than in several recent years. 
The booming ground on the Yeatter Sanctuary appeared to be the focal point of 
fall booming activity on the study area, from two standpoints: it was the most 
consistently active of the three booming grounds used and had the largest number 
of prairie chickens. 
Previous to the fall of 1 968 only two sanctuaries (Yeatter--77 acres and 
McGraw--20 acres) of the eight sanctuaries now in the 494-acre refuge system were 
regularly used by prairie chickens for nesting and roosting activities. Although 
no nests were found on the 60-acre Donnelley Sanctuary in 1 966 , it is encouraging 
to note that prairie chickens are now using this sanctuary regularly for night- 
roosting and day-resting activities. The five other sanctuaries are in early 
stages of cover development, but they should expedite greater dispersal of the 
Bogota flock, beginning in 1967* 
6. R abbit Management J. A. Bailey, J. C. Hanson 
Results of feeding trials conducted during spring and summer with young 
cottontails have been reported (Monthly Wildlife Research Letters, August and 
October, 1985, and August, 1 986 ). Feeding trials conducted during September and 
October, 1966, with cottontails weighing between 435 and 735 grams are reported 
here. Twelve animals were fed single-species diets during the 10-day trials. 
Bluegrass ( Poa sp.), orchard grass ( Dactyl is qiomerata ), timothy (P h1eum pratense ), 
alfalfa ( Medicaao sativa ), and chicory (Cichorium intybus ) were fed to two animals 
each. Rugel's plantain ( Plantago ruqelii) and Lamb 1 s-quarters (Chenopodium album ) 
were fed to one animal each. 
The most palatable foods were chicory and alfalfa. The rabbits consumed these 
foods at rates of 45 percent and 30 percent of their body weights per day, 
respectively (fresh-weight basis). Least palatable were bluegrass and timothy, 
each of which was consumed at a rate of 12 percent of body weights per day. Only 
one animal, fed timothy, failed to survive for 10 days. Rabbits fed single-species 
diets of bluegrass, timothy, and Lamb 1 s-quarters lost weight, while rabbits fed 
single-species diets of orchard grass, alfalfa, chicory, and plantain gained weight 
during the experiment. Greatest weight gains were made by animals fed chicory 
and plantain. The digestibilities of dry matter in six of the foods were: bluegrass, 
44 percent; orchard grass, 46 percent; timothy, 50 percent; alfalfa, 62 percent; 
