The authors of this paper spent the summer of 1920 in western Michigan
studying the mammals of the region for the Michigan Geological and
Biological Survey. From June 25 to August 4 was spent in the Cisco Lake
Region with headquarters on Lindsley Lake; August 6 to August 20 a camp
was maintained in the woods four miles southeast of Little Girl's
Point; and from August 20 to September 6 was spent working from a camp
on the western shore of Lake Gogebic, about three miles south of Lake
Gogebic Station. The first two camps were in Gogebic County, the third
in Ontonagon County.
The field work was performed jointly by the two authors, under the
direction of the senior author, who is responsible for the
identification of the species, the descriptions of the general areas
and of the habitats, and is jointly concerned in writing the annotated
list.
In addition to our own records, we have secured many valuable notes on
the distribution of the larger species from J. E. Fischer, of
Merriweather, Ontonagon County, a trapper of many years' experience;
and from Benjamin J. Twombley, of Bent's Resort, Wisconsin, who has
made many observations on the mammals of the Cisco Lake Region. We have
also added a number of records from J. E. Marshall, who trapped for
many years, beginning 1884, in Ontonagon and Gogebic counties, and from
Ole Petersen, at one time a trapper at Gogebic Lake.
The habitats in which records of occurrence have been obtained for the
region under consideration are listed under each species; and the
number of individuals taken, or seen and positively identified, in each
habitat are given. From the figures a rough estimate of the relative
abundance of the various species in the different habitats can be
obtained, but the various habitats were not trapped or studied equally
intensively, and for the larger and the rarer forms the numbers give
little dependable data on relative abundance.