Vol. 12, No. 10 
Page 3 
found in the March burn II cover (14.3 nests per 100 acres). Most of the burning 
done so far was of light to moderate intensity whereby a patchwork of unburned 
residual vegetation was usually left on the ground. Seemingly, an ample amount 
of nest material was still present for the nesting season immediately following 
a March or August burn. However, the limited data tend to indicate that at least 
one growing season must pass before a burned field is acceptable for nesting. 
In 1969, wet weather conditions may have been an important factor influencing 
nest site selection. Heavy layers of duff on the ground appeared to be more 
important to nesting hens in 1 969 than in any of the preceding 6 years of this 
study. For example, in six fields for which valid comparisons could be made 
between numbers of nests in March burn I, August burn I-, and unburned portions of 
the fields, all eight of the nests found in the six fields were in the unburned 
port ions. 
6. Rabbit Management G * B * Rose 
The annual fall censusing of cottontail rabbits on the 100-acre (40-hectare) 
4-H Area at Robert Allerton Park is being continued this fall, the 14th 
successive year. One hundred thirty-one rabbits were trapped and ear-tagged 
during a 10-day period at the beginning of October. Several population estimates 
were calculated from the capture and recapture data. The Schnabel (short form) 
estimate is 157 animals; the geometric maximum likelihood estimate (MLE-G) is 
288; and the maximum likelihood estimate from a regression of the logarithm of 
the number of individuals in a frequency class on frequency of capture (MLE-R) 
is 279. The MLE-R is regarded as the best method of estimation. This estimate 
of 279 is much larger than the estimates of 177 a nd 211 for October and November 
1968, and of 170 and 1 76 for October and November 1967; is the la rgest 
estimate since the years 1956-61. 
