MONTHLY WILDLFIE RESEARCH LETTER 
Vol. 3, No. 1 
Page 3 
Estimates of opossum populations were made for the 1,806-acre study area 
in Piatt County for 1958 and 1959. The estimate for 1958, based on information 
obtained by comparing toe-clipped and unmarked young which were live-trapped, was 
222 opossums per square mile. That for the same year, based on the ratio of 
tagged and untagged opossums live-trapped during 1959, was 234 per square mile. 
The population estimate for 1959 based on the first method was 244 opossums per 
square mile. 
Sex ratios of young examined while in the pouch and those young live-trapped 
indicated that there was no difference between the two; both were 50:50. This 
indicates no differential mortality between the sexes and no differential movements 
up to the time the young are first live-trapped away from the females. 
W-61-R-3 F. Greeley, J. Ellis 
Data from the pheasants fed different amounts of calcium was punched into 
tapes and matrix analysis was performed on the Illiac digital computer. The 
analysis showed that there were statistically significant trends in ash content 
of the femur and tibia of hen pheasants fed different amounts of calcium. The 
tibia weights of hens on a high calcium diet were significantly heavier than the 
tibias of hens on a low calcium diet. Losses in body weight were significantly 
greater in hens on a calcium-deficient diet than in hens on high calcium in spite 
of low egg-production of the former group. 
During January, 131 pheasants (114 hens and 17 cocks) were trapped in the 
south-central part of Livingston County and released on the Neoga area. The age 
ratio among the hens was 1.00 juveniles per adult; the age ratio among the cocks 
was 0.89 juveniles per adult. A total of 323 wild-trapped pheasants (267 hens 
and 56 cocks) have been released on the- Neoga area during the past 2 months. 
