PORE ede GE 
HE two studies presented here, Survey 
of the Illinois Fur Resource and Illi- 
nois Furbearer Distribution and Income, 
represent sincere attempts to obtain by dif- 
ferent methods a reasonably reliable measure 
of the valuable fur resource of Illinois. 
Each study has certain inherent strengths 
and weaknesses. ‘The oral survey, basis for 
the Brown & Yeager report, was intensive 
in its technique. he analysis of fur-takers’ 
reports, basis for the Mohr report, was 
extensive. The Brown & Yeager data rep- 
resent but 1.7 per cent of the area of the 
state, but within the strips actually surveyed 
were included all trappers, licensed and un- 
licensed, those who reported catches and 
those who did not. ‘The Mohr figures repre- 
sent every county in the state but they are 
selective in that, of necessity, they take into 
account only those trappers who reported 
their catches; that is, 10 to 23 per cent of 
the total number of licensed trappers. The 
Brown & Yeager data are based on oral 
answers given 15 days to over 14 months 
after the end of the trapping season covered 
by the questionnaire; no penalty for false 
answers was provided. ‘The Mohr data are 
based on written answers given not later 
than the fifth day of the month next succeed- 
ing the month for which each report was 
made; persons making false answers could 
be prosecuted under the law. The Brown 
& Yeager report covers two trapping sea- 
sons; the Mohr report covers eight. 
As must be expected in reports based on 
sampling, particularly sampling in which the 
human element plays an important part, 
calculated figures in these two reports do 
not coincide. However, the figures do not 
vary abnormally and, in nearly every in- 
stance of identical subject matter, a close 
correlation or parallel relationship exists 
between the two sets of figures. 
The closeness of the corresponding figures 
and the degree of correlation between the 
two sets of figures indicate that, despite the 
errors that may have resulted from small 
or faulty sampling and despite possible 
errors resulting from inexact memory of 
persons questioned, the two reports give for 
the Illinois fur resource a picture so nearly 
accurate that it can serve as a useful guide 
in many matters pertaining to the fur-bear- 
ing animals of the state. 
The two reports agree in placing the value 
of the annual fur take of Illinois at over 
$1,000,000, and they agree on the relative 
values of the various fur-bearing animals. 
The species that can profitably be fostered 
and those that cannot is clearly indicated 
by a study of the two reports. 
The fur income of the state is still de- 
rived, as in pioneer years, from cropping a 
natural resource as it occurs in the wild, 
with very little conscious management by 
man. Much of the fur harvest is carried on 
by low income groups at a time of year in 
which other sources of income are scarce. 
Both of these facts should be considered 
in relation to the conservation or expansion 
of the Illinois fur industry and to the fram- 
ing of laws regulating it. 
The present reports are an outgrowth of 
earlier and less comprehensive studies by the 
Natural History Survey and its predeces- 
sors, some published (Wood 1910, Forbes 
1912) and some not (Driver 1930, Ras- 
mussen 1931). The fine cooperation of the 
State Department of Conservation, Spring- 
field, Ill., has made possible the present more 
conclusive reports; for the Brown & Yeager 
study, this department made available spe- 
cial research investigation funds adminis- 
tered in cooperation with the U. S. Fish and 
Wildlife Service under terms of the Federal 
Aid in Wildlife Restoration Act, commonly 
known as the Pittman-Robertson Act, and 
for the Mohr report it provided essential 
records and information. The Natural His- 
tory Survey is most appreciative of this 
assistance. 
Mr. James S. Ayars, Technical Editor of 
the Survey, has contributed much to the 
accurate presentation and unification of the 
data of the two separate manuscripts in- 
volved and their adaptation to the general 
Survey format. His services in this connec- 
tion are appreciated by all concerned. 
T. H. Frison, Chief 
Illinois Natural History Survey 
