Vol. 4, No. 12 
Page 3 
| 5. Investigations of Fuibearers Ralph J. Ellis 
A mink study is expected to begin in 1962. Such a study would be facilitated 
by background knowledge of mink weights, sex ratios, age ratios and certain physical 
characteristics of the populations concerned. Recently an opportunity to obtain 
such information occurred. 
Incidental to the raccoon studies, 140 skinned mink carcasses were collected 
during December at the Ed Bauer & Son Fur Company in the southern hunting zone and 
the Perardi Brothers Fur Company in the northern hunting zone. The carcasses were 
later weighed and measured. The heart, liver, lungs, one eye, two adrenals and 
two kidneys were removed for examination and weighing. Two ovaries were removed 
from each female and one testis plus baculum were taken from each male. Each uterus 
was examined for placental scars. 
Some of the minks pelted each year in Illinois have light gray underfur and 
dark brown guard hair. These animals are called "cotton" minks in contrast to most 
other minks whose underfur and guard hair are both dark brown. Non-cotton minks are 
three to four times more valuable than cotton minks. 
Eighty-five of the mink carcasses examined came from animals whose fur was 
identified as cotton or non-cotton, table 2. These data suggest that the cotton 
condition is more characteristic of females than of males. Females made up 30.5 
per cent of the 85 mink whose fur condition was known. Yet, females comprise 
57.0 per cent of the cotton minks. 
^ Data in table 2 show that males accounted for approximately two-thirds of the 
harvest. There were no significant differences between the sex ratios of the 
carcasses examined prior to and after December 15. The student*s t-test, 95 per 
cent confidence level, was used to test for differences*, 
Table 2.—Sex and "cotton" fur classes of 140 minks collected at the Ed Bauer 
& Son Fur Company, Smithboro and the Perardi Brothers Fur Company, Farmington 
during December, 1961. 
Non-cotton 
d $ 
Cotton 
d § 
All 
d 
Minks 
$ 
Bauer Fur Company 
(Northern hunting 
zone) 
13 5 
2 
3 
50* 
28*- 
Perardi Fur Company 
(Southern hunting 
zone) 
40 13 
4 
5 
44 
18 
Both Fur Companies 
53 18 
6 
8 
94 
46 
Includes some minks whose fur condition was unknown 
