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  NUMBER 86            JUNE 24, 1920

  OCCASIONAL PAPERS OF THE MUSEUM OF
  ZOOLOGY

  UNIVERSITY OF MICHIGAN

  ANN ARBOR, MICHIGAN PUBLISHED BY THE UNIVERSITY




THE MAMMALS OF WARREN WOODS, BERRIEN COUNTY, MICHIGAN

BY LEE RAYMOND DICE


Few detailed studies of the mammal associations of the forests of the
United States have been made. But if we are ever to know, for our
different species of mammals, the natural environments under which
their evolution and differentiation occurred, we must study and
describe their habitats and habitat limitations before all the native
areas in the country have been altered by the activities of mankind.
As a contribution to this subject the following paper is presented.

The Warren Woods are a state preserve under the Edward K. Warren
Foundation. They are located in Berrien County, Michigan, about three
miles north of Three Oaks. The preserve consists of about two hundred
acres, of which somewhat less than half is in clearing and the
remainder mostly covered by forest, much of it still nearly in its
primitive condition.

[Illustration: FIG. 1.--Sketch map of Warren Woods Preserve. The
distribution of the various mammal habitats is indicated.]

The topography is nearly level, though the area is cut by a number of
ravines draining to the Galien River, which flows through the
preserve. Along the river and in its bends there are moderate-sized
flood-plains.

On the flood-plains a few small buttonbush swamps occur; and along the
margins of the river a few freshly formed mud bars have not yet become
forested; but most of the flood-plains are covered by heavy forest.
The higher ground, except that in the clearing, is covered by heavy
beech-maple forest.

Several types of habitats are represented in the clearing: in a few of
the cleared ravines a thick growth of sedges and iris occurs; on the
higher ground small areas are dominated by rushes, other areas by
sedges, while the greater part is covered by grass. In parts of the
clearing blackberries and other shrubs have grown up to form thickets,
and in many places, especially along the edges of ravines,
second-growth trees of oak, maple, or beech grow in the thickets or
form small groves.

The mammal habitats found on the preserve may be listed as follows:

_Natural habitats_

    Aquatic habitat
    Buttonbush-swamp habitat
    Shore habitat
    Mud-bar herbage habitat
    Flood-plain forest habitat
    Beech-maple forest habitat
    Aerial habitat

_Modified and artificial habitats_

    Second-growth, forest and scrub habitat
    Cleared-ravine sedge habitat
    Cleared-upland rush habitat
    Cleared-upland sedge habitat
    Cleared-upland blue-grass habitat
    Cultivated field habitat
    Orchard habitat
    Edificarian habitat

It is unfortunate that all of the area in clearing and about half of
the forested area on the preserve has been and is being heavily
pastured by cattle and horses. The presence of stock has changed the
native conditions so much that, so far as interpreting the primitive
mammal associations is concerned, little dependence can be placed on
studies made in that portion of the preserve. The grass and herbage is
extensively eaten off, and many of the shrubs and young trees eaten
or badly mutilated. Under the pastured forest little underbrush or
herbage remains, and the conditions are very poor for small mammals.

In all the forest, in the unpastured as well as in the pastured part,
a number of trees have been cut out in former years, and although no
trees are now being cut down, all the trees and branches which fall
are being cut up for firewood. This results in there being few logs
and little dead brush on the ground, and removes a favorite place for
small mammal nests and runways, as well as largely eliminating as
mammal food the insects and larvae which are dependent on decaying
wood. However, with the exception of the removal of the logs and of a
few trees, that part of the forest to the north of the river is still
in practically its native condition, and it shows no evidence of ever
having been pastured. It is thus a splendid place for the study of the
native faunal conditions.

Although the whole area in the preserve is small there are other areas
of adjoining forest along the Galien River, so that, for the smaller
mammals at least, the results of the study and trapping should
indicate the primitive habitat distribution. The relative abundance of
the different species, however, is probably much changed by the
decrease throughout the whole region of the carnivores, which have
been much hunted and trapped by man.

The mammals of Warren Woods were intensively studied by the author
from July 3 to September 3 in the summer of 1919. A camp was
maintained near the edge of the Woods, and by trapping and hunting
every effort was made to determine the mammal fauna of the preserve.
From one hundred to two hundred traps for small mammals and about
twenty traps for the larger species were kept constantly in operation.
A small amount of trapping was done in the fields and along the
roadsides immediately adjoining the Woods and a few records were
secured from the camp house.

The work was supported by the Michigan Geological and Biological Survey.
Dr. Alexander G. Ruthven directed the work and gave much assistance in
securing the needed collecting equipment. Much help was given by George
R. Fox, Director of the Warren Foundation, not only in getting to and
from the camp at the Woods and in numerous other courtesies, but also in
information about the Woods and about the mammals there. The plant
identifications were made by Mr. C. Billington.

The figures following the specific names in the lists of mammals from
each habitat indicate the number of individuals trapped, shot, or seen
and positively identified in that habitat.




NATURAL HABITATS


_Aquatic habitat_:

     _Mustela vison mink._ Mink. Reported.

     _Fiber zibethicus zibethicus._ Muskrat. Reported.

Mink and muskrat are reported by residents to occur in the Galien
River in and near Warren Woods, but I was unable to secure any
specimens though traps were set for them; neither did I see any signs
of their presence.


_Buttonbush-swamp habitat_:

     _Peromyscus leucopus noveboracensis._ Northern white-footed
     mouse. 8.

     _Mus musculus musculus._ House mouse. 2.

A large buttonbush swamp occurs in the preserve just south of the
Galien River, but around this the native trees have been cut away and
over its accessible edges it has been heavily pastured, so that it is
not at all in its natural conditions, and it was not trapped. In the
unpastured flood-plain north of the river there is another buttonbush
swamp of several hundred yards extent. This latter area was the one
selected for study.

In this typical swamp the buttonbush, _Cephalanthus occidentalis_, is
practically the only plant present. It thickly covers the area with
its tangled branches, which grow to heights of four to ten feet. The
water had drained away in August, leaving the ground bare, though
still wet and soft. Under the cover of the buttonbush there is no
herbage whatever, and upon the ground there are only a few decaying
logs and a few small sticks, which often carry a light growth of moss.

Around the edges of this swamp there is a narrow belt of thick herbage,
closely encroached upon by the typical forest of the flood-plain.

Fifty mouse traps set in this habitat took eight northern white-footed
mice and two house mice the first night, August 5.


_Shore habitat_:

     _Procyon lotor lotor._ Raccoon. Tracks.

     _Peromyscus leucopus noveboracensis._ Northern white-footed
     mouse. 1.

Along the shores of the Galien River a narrow strip of bare ground was
exposed in July and August. The ground of this strip is mostly mud,
but in a few places it is sand or gravel. Usually the habitat is
narrow, but in some places it is five to ten feet wide.

Tracks of raccoon were frequent on the shore along the river. From a
few mouse traps set on the bare mud shore one northern white-footed
mouse was taken August 4 beside a drift log.


_Mud-bar herbage habitat_:

     _Peromyscus leucopus noveboracensis._ Northern white-footed
     mouse. 4.

A few small recently formed mud bars occur along the Galien River in its
outer bends. These bars have not yet had time to become forested, and on
their outer edges nearest the river there is usually no vegetation, this
part being included in the shore habitat. On their older portions next
the forest of the flood-plains occurs a thick growth of herbs, several
annual grasses, and rarely a willow, _Salix_ sp., or a seedling tree of
white elm, _Ulmus americana_, cottonwood, _Populus deltoides_, maple,
_Acer rubrum_ or _saccharinum_, and others of the typical flood-plain
species. The vegetation during August is very thick, and reaches a
height of four to six feet. The soil is either mud or in a few places
fine sand, and the ground is quite moist.

In this habitat four northern white-footed mice were trapped August 3-4.


_Flood-plain forest habitat_:

     _Scalopus aquaticus machrinus._ Prairie mole. Ridges.

     _Blarina brevicauda talpoides._ Short-tailed shrew. 4.

     _Procyon lotor lotor._ Raccoon. 1.

     _Mustela noveboracensis noveboracensis._ New York weasel. 1.

     _Peromyscus leucopus noveboracensis._ Northern white-footed
     mouse. 52.

     _Microtus pinetorum scalopsoides._ Northern pine vole. 5.

     _Mus musculus musculus._ House mouse. 2.

     _Zapus hudsonius hudsonius._ Hudson Bay jumping mouse. 1.

     _Erethizon dorsatum dorsatum._ Canada porcupine. Tooth marks.

     _Marmota monax monax._ Southern woodchuck. 4.

     _Sciurus hudsonicus loquax._ Southern red squirrel. 4.

     _Sylvilagus floridanus mearnsii._ Mearns cottontail. 1.

There are considerable areas of flood-plain along the Galien River, and
except for the recently formed mud bars the flood-plains are heavily
covered with a mixed forest in which the linden, _Tilia americana_,
white elm, _Ulmus americana_, and sycamore, _Platanus occidentalis_, are
conspicuous species. Under this forest there are a few small trees, but
there is very little underbrush. The herbage also is sparse and, though
in a few places there is a considerable growth of ferns, grasses, and
sedges, and of other herbs, there are also many bare areas.

One of the significant features of the flood-plains, so far as the
mammals are concerned, is the flooding to which these areas are
subjected during the spring high-water. At that time the flood-plain for
a number of days or weeks may be covered with several feet of water.

During the period between July 29 and August 28 a total of one hundred
and seventy mouse traps set in the flood-plain forests along the
Galien River took for the first nights' trapping, twenty-two northern
white-footed mice and one house mouse. Short-tailed shrews, more
white-footed mice, pine voles, and a jumping mouse were secured on
nights after the first. Larger traps took during the whole period one
raccoon, one New York weasel, and two woodchucks. Several other
woodchucks and a number of red squirrels were seen. Ridges of moles
were numerous, but no specimens were secured. Tooth marks on an old,
partly fallen linden were probably made, perhaps a number of years
ago, by a porcupine.

Throughout the woods there are a number of small ravines. These
ravines are forested with trees mostly of the flood-plain type, and
there is evidence in many of the ravines, at least in their lower
parts, that flooding occurs in the ravine bottom during the spring.

Fifty mouse traps set August 26 in a large ravine north of the county
road took on the first day five northern white-footed mice and one
house mouse. Short-tailed shrews, more white-footed mice, and pine
voles were trapped on following days. Here also red squirrels and a
cottontail were seen, and tracks of raccoon noted. Evidently the fauna
is the same as that of the flood-plain, with which it is here included.


_Beech-maple forest habitat_:

     _Blarina brevicauda talpoides._ Short-tailed shrew. 7.

     _Procyon lotor lotor._ Raccoon. Tracks.

     _Peromyscus leucopus noveboracensis._ Northern white-footed
     mouse. 86.

     _Microtus pinetorum scalopsoides._ Northern pine vole. 5.

     _Zapus hudsonius hudsonius._ Hudson Bay jumping mouse. 1.

     _Marmota monax monax._ Southern woodchuck. Burrows.

     _Tamias striatus lysteri._ Northeastern chipmunk. 1.

     _Sciurus hudsonicus loquax._ Southern red squirrel. 10.

     _Sciurus niger rufiventer._ Fox squirrel. 7.

     _Sylvilagus floridanus mearnsii._ Mearns cottontail. 1.

The climax forest of the region is dominated by the beech, _Fagus
grandiflora_, and the sugar maple, _Acer saccharum_. The trees in this
forest are very large, so that the forest crown is high and the shade
dense. Only a few small trees occur and these are mostly young beeches
and young sugar maples. The underbrush varies much in height and
denseness; mostly it is quite open, so that one can easily walk
through the forest, but in a few places the growth is more dense.
Common members of the underbrush on the higher ground are the small
beeches, sugar maples, and the spice-bush, _Benzoin aestivale_; while
on the lower benches along the river seedlings of the paw-paw dominate
the undergrowth. The ground is heavily covered by decaying leaves and
a little dead brush and fallen branches, but nearly all the logs have
been removed. Early in the spring a thick growth of herbs covers the
ground, but by July the herbs are mostly gone, only a few remaining,
and there are many small bare areas covered only by leaves. The soil
under this forest seems to be mainly clay; in spring or after heavy
rains pools of water are formed, and these remain for a long time.

Between July 21 and August 27 a total of two hundred and eighty-five
mouse traps set in the upland forest took on the first nights one
short-tailed shrew and thirty northern white-footed mice. In addition
to these species pine voles and a jumping mouse were trapped on days
after the first. One shrew was caught alive August 30, as he was
running about on the forest floor at 7:30 A.M. A few tracks of raccoon
were seen from time to time on the road leading through the woods. A
few fresh burrows of woodchucks were noted at the edges of benches and
of ravines. A few red squirrels were seen at different times and two
collected. Fox squirrels were rare, being noted only a few times; Mr.
Norman A. Wood also saw these squirrels on two occasions in May. One
cottontail was shot, in the climax forest. Mr. Wood collected a
chipmunk in the climax forest on May 15, 1918, and saw another in the
same habitat in May, 1919.


_Aerial habitat_:

Bats were seen on a few evenings, flying about over the climax forest,
and over the adjacent region, but they were extremely rare, and
efforts to shoot a specimen failed.




MODIFIED AND ARTIFICIAL HABITATS


_Second-growth forest and scrub habitat_:

     _Mustela noveboracensis noveboracensis._ New York weasel. 1.

     _Mephitis nigra._ Eastern skunk. 1.

     _Peromyscus leucopus noveboracensis._ Northern white-footed
     mouse. 5.

     _Microtus pennsylvanicus pennsylvanicus._ Pennsylvania vole. 4.

     _Mus musculus musculus._ House mouse. 1.

     _Marmota monax monax._ Southern woodchuck. 1.

     _Sciurus hudsonicus loquax._ Southern red squirrel. 1.

     _Sylvilagus floridanus mearnsii._ Mearns cottontail. 5.

Small trees and brush have grown up along the edges of many of the
ravines in the cleared fields in and surrounding the preserve. Many of
the trees are oaks, but beech and hard maple also occur, a few of them
being relics from the original forest. Considerable brush is present,
formed by a large variety of species. A few other small patches,
especially in ravine bottoms and on flood-plains have been allowed to
grow up to brush and small trees. In nearly every case these areas are
heavily pastured.

The conditions here included in the second-growth forest and scrub
habitat are not homogeneous, but differ in each different location
where the habitat is found, tree and shrub species abundant in one
situation not being present in another. The habitat is usually narrow
in extent, being often confined to the width of the steep ravine wall.

Owing to its poor development and uncertain characteristics no
intensive trapping was done in this type of habitat. A weasel was
trapped in open beech-maple-oak forest at the edge of a cleared
ravine, and a woodchuck was shot in the same type of habitat. Another
woodchuck and a skunk were trapped at different times in low willow
brush on the banks of the river just north of the woods. Northern
white-footed mice, Pennsylvania voles, and a house mouse were trapped
in thick oak brush and trees alongside a road north of the woods. A
red squirrel was shot in second-growth oak and aspen woods in the
north part of the preserve, and they were seen in open woods along
ravines. Cottontails were noted a few times in blackberry thickets,
in brush in ravines, in clearings along the river, and in
beech-maple-oak forest along ravines.


_Cleared-ravine sedge habitat_:

     _Blarina brevicauda talpoides._ Short-tailed shrew. 1.

     _Peromyscus leucopus noveboracensis._ Northern white-footed
     mouse. 3.

     _Microtus pennsylvanicus pennsylvanicus._ Pennsylvania vole. 5.

A large ravine south of the river had been cleared of trees evidently
several years previously, and it has now grown up mostly to sedges,
grass, and iris in its more moist parts. Along the little brook which
flows through the ravine there is a fringe of willows, and among the
sedges a number of shrubs and small trees occur, mostly thorns and a
few young sycamores and black walnuts.

Fifty mouse traps set in this habitat took on the first day, August
16, three northern white-footed mice and three Pennsylvania voles.
More voles and a short-tailed shrew were taken on later days.


_Cleared-upland rush habitat_:

     _Mephitis nigra._ Eastern skunk. Den.

     _Peromyscus maniculatus bairdii._ Prairie white-footed mouse. 1.

     _Synaptomys cooperi._ Cooper lemming-vole. 1.

     _Microtus pennsylvanicus pennsylvanicus._ Pennsylvania vole. 7.

     _Microtus ochrogaster._ Prairie vole. 1.

     _Citellus tridecemlineatus tridecemlineatus._ Thirteen-striped
     ground squirrel. 2.

In the shallow, poorly drained depressions of the cleared upland the
vegetation is dominated by rushes, which grow in clumps and form a
thick growth, reaching a height of about one meter as a maximum. At
the edges of the habitat and in places not thickly covered by the
rushes a growth of sedges, grasses, and moss covers the ground; but
under the thickest growth of rushes the ground is bare and is
evidently covered by water during a part of the year. On this upland
one small pond surrounded by rushes did not dry up until late in
August. In a few places small blackberry thickets occur in the areas
of rushes and dominate all other plants.

Fifty traps set in this habitat, on August 8, took on the first night
one prairie white-footed mouse and one Pennsylvania vole; the prairie
white-footed mouse was taken just at the edge of the growth of rushes.
Other Pennsylvania voles as well as a lemming-vole, a prairie vole,
and several young ground squirrels were secured on later nights by the
same trap-line. A skunk den was situated in a blackberry thicket in
the midst of the largest patch of rushes.


_Cleared-upland sedge habitat_:

     _Peromyscus maniculatus bairdii._ Prairie white-footed mouse. 3.

     _Microtus pennsylvanicus pennsylvanicus._ Pennsylvania vole. 1.

     _Microtus ochrogaster._ Prairie vole. 9.

     _Mus musculus musculus._ House mouse. 1.

     _Citellus tridecemlineatus tridecemlineatus._ Thirteen-striped
     ground squirrel. Burrows.

Sedges are dominant over a part of the cleared upland, occurring on
the moist gentle slopes which are too well drained for rushes, but not
in any numbers on the drier and higher parts of the upland. With the
sedges there are a few grasses, and the ground is sometimes covered by
a moss, but the sedges are by far the most abundant plant.

Fifty mouse traps set in this habitat took on the first night, August
15, one prairie white-footed mouse and one prairie vole. Other prairie
voles and white-footed mice were taken on later nights, as well as one
Pennsylvania vole and one house mouse. Burrows of the thirteen-striped
ground squirrel were numerous in the sedges.


_Cleared-upland blue-grass habitat_:

     _Peromyscus maniculatus bairdii._ Prairie white-footed mouse. 12.

     _Mus musculus musculus._ House mouse. 1.

     _Citellus tridecemlineatus tridecemlineatus._ Thirteen-striped
     ground squirrel. 23.

The most widespread habitat of the cleared upland on the south part of
the preserve is the blue-grass habitat. In this habitat the
blue-grass, _Poa_, is the dominant plant, growing to a height of
usually not over 0.5 meter. With the blue-grass are associated a few
thistles, yarrow, and several other herbs. During the whole period of
my stay in the region, July and August, the habitat was very dry, and
the grass and herbs had mostly dried up. This habitat and all the
other habitats of the clearing were being heavily pastured by stock.

Trap-lines totaling one hundred mouse traps, set on August 6 and
August 18, took on the first nights two prairie white-footed mice, one
house mouse, and one young thirteen-striped ground squirrel. More
white-footed mice were taken on later nights. Many ground squirrels
were taken in larger traps at the mouths of their burrows; most of
these were young of the year, and all of them were very fat in
preparation for their approaching hibernation.


_Cultivated field habitat_:

     _Scalopus aquaticus machrinus._ Prairie mole. 1.

     _Peromyscus maniculatus bairdii._ Prairie white-footed mouse. 23.

     _Microtus ochrogaster._ Prairie vole. 1.

     _Mus musculus musculus._ House mouse. 2.

     _Sylvilagus floridanus mearnsii._ Mearns cottontail. 2.

Cultivated fields occur throughout the region about the woods, but the
only ones in which trapping was done were wheat stubble-fields. After
the wheat was cut off these stubble-fields grew up rather thickly to
weeds. On the ground there were a number of fallen heads of wheat and
some shelled-out grain, furnishing abundant food for mice.

Seventy mouse traps set in a wheat stubble-field just north of Warren
Woods, caught on the first nights, August 13 and August 29, sixteen
prairie white-footed mice. Other white-footed mice and two house mice
were taken on later nights. Several cottontails were seen in this
field, and a few mole ridges were noted. A prairie mole was taken by
Clifford Reid in a grassy patch at the edge of a garden. In another
wheat field the Helming boys picked up a prairie vole.


_Orchard habitat_:

     _Peromyscus leucopus noveboracensis._ Northern white-footed
     mouse. 1.

     _Microtus pennsylvanicus pennsylvanicus._ Pennsylvania vole. 2.

No especial study of the mammal life of the orchard was made, and no
intensive trapping was done in the habitat. However, the orchard cannot
be included in any of the other habitats recognized in the region.

A northern white-footed mouse was caught alive by the Helming boys in
an orchard on July 16. A vole was seen to cross a road in a small
orchard on July 15; a trap was set and two Pennsylvania voles secured,
one a young of the year.


_Edificarian habitat_:[1]

     _Blarina brevicauda talpoides._ Short-tailed shrew. 1.

     _Peromyscus leucopus noveboracensis._ Northern white-footed
     mouse. 2.

     _Rattus norvegicus._ Norway rat. 4.

     _Mus musculus musculus._ House mouse. 22.

     _Sylvilagus floridanus mearnsii._ Mearns cottontail. 2.

From time to time a few traps were set in the old farmhouse and in the
barn and other outbuildings of our camp. In these buildings northern
white-footed mice, Norway rats, and house mice were taken. Several
cottontails were seen in and under the old barn. The Helming boys
trapped a short-tailed shrew and also house mice and a white-footed
mouse in the basement of their house.




RECORDS OF THE NUMBER OF EMBRYOS


All the females taken were examined for embryos, and the results are
here tabulated by species and dates. The term _subadult_ is used to
indicate an individual which has reached adult size, but which is
still immature as shown by the pelage, unworn condition of the teeth,
and weakness of the skull sutures. For each individual the age is
first stated, next the number of embryos if any, and last the length
of the embryos in millimeters measured as they lie rolled in the fetal
membranes. For embryos too small to measure with field equipment the
term _small_ is applied.

These records indicate the breeding period of the different species
and the number of young.


_Mephitis nigra._ Eastern skunk

    August 19: subadult, 0 embryos.


_Peromyscus leucopus noveboracensis._ Northern white-footed mouse

    July 16: adult, 3 embryos, size small.
    July 21: adult, 0; adult, 0.
    July 22: adult, 5, 10 5 mm.; subadult, 0.
    July 23: subadult, 0.
    July 25: juvenile, 0, juvenile, 0; juvenile 0; subadult, 3, small.
    July 30: adult, 0; adult, 0; adult, 0; subadult, 0.
    August 2: adult, 0; subadult, 2, small; subadult, 0; subadult, 0.
    August 5: adult, 5, small; subadult, 0.
    August 23: subadult, 0; adult, 5, 10 mm.
    August 24: adult, 5, 8 mm.; adult, 0; adult, 0; adult, 3, small.
    August 25: adult, 5, 23 mm.; adult, 0; adult, 4, small; adult, 3,
        small.
    August 26: subadult, 4, 8 mm.; adult, 0.
    August 29: adult, 4, 17 mm.


_Peromyscus maniculatus bairdii._ Prairie white-footed mouse

    August 7: subadult, 0.
    August 10: adult, 5, 8 mm.
    August 13: adult, 3, 8 mm.; adult, 0.
    August 20: adult, 5, small.
    August 28: adult, 4, 17 mm.; adult, 4, 13 mm.
    August 29: adult, 5, 17 mm.
    August 30: adult, 0; adult, 4, 11 mm.


_Synaptomys cooperi._ Cooper lemming-vole

    August 11: adult, 2, 10 mm.


_Microtus pennsylvanicus pennsylvanicus._ Pennsylvania vole

    July 15: adult, 4, not measured, juvenile, 0.
    August 9: subadult, 0.
    August 10: subadult, 0; subadult, 0.
    August 13: subadult, 0.
    August 16: adult, 0.
    August 24: adult, 4, 11 mm.


_Microtus ochrogaster._ Prairie vole

    July 25: juvenile, 0.
    August 15: adult, 4, small.


_Microtus pinetorum scalopsoides._ Northern pine vole

    July 22: juvenile, 0.
    July 25: juvenile, 0.
    July 31: adult, 0.


_Rattus norvegicus._ Norway rat

    July 11: adult, 7, 37 mm.
    July 12: adult, 9, 26 mm.
    July 14: juvenile, 0.


_Mus musculus musculus._ House mouse

    July 9: subadult, 0.
    July 10: juvenile, 0; subadult, 0.
    July 11: adult, 0 (was nursing 3 or more half-grown young).
    July 17: adult, 11, 6 mm.
    July 22: adult, 7, 3.5 mm.


_Zapus hudsonius hudsonius._ Hudson Bay jumping mouse

    July 27: subadult, 0.


_Marmota monax monax._ Southern woodchuck

    July 11: adult, 0.
    July 28: juvenile, 0.
    August 3: adult, 0.
    August 22: juvenile, 0.


_Citellus tridecemlineatus tridecemlineatus._ Thirteen-striped ground
squirrel

    August 14: adult, 0.


_Sciurus hudsonicus loquax._ Southern red squirrel

    July 24: adult, 0.
    July 27: juvenile, 0.


_Sciurus niger rufiventer._ Fox squirrel

    August 11: subadult, 0.


_Sylvilagus floridanus mearnsii._ Mearns cottontail

    July 21: adult, 4, 70 mm.




NEW STATE RECORD OF THE PRAIRIE VOLE


The specimens of prairie vole, _Microtus ochrogaster_, listed above from
the sedges and rushes of cleared upland in the Warren Woods preserve and
from a nearby wheat field constitute the first authentic record of the
species from Michigan. The prairie vole had previously been erroneously
reported to be abundant in Washtenaw County by Covert[2], who evidently
mistook the Pennsylvania vole for this species.




OTHER MAMMALS OF THIS REGION


The following notes on mammals formerly or at present living in the
region but not found by me in Warren Woods are based mostly on
information furnished by George R. Fox, Director of the Edward K.
Warren Foundation, and by William Schmidt, a trapper and hunter.

_Didelphis virginiana virginiana._ Virginia opossum. Three were seen
and one captured in Three Oaks in the winter of 1919-20, and another
was found in a granary on the outskirts of the town. The previous
winter one was shot just southwest of town, and another was seen in a
ravine north of Harbert. One was killed in Warren Woods some time ago.

_Condylura cristata._ Star-nosed mole. Mr. Hans captured one four miles
south of Three Oaks, near the Indiana line in 1919, and brought the skin
to Mr. Fox. One was taken by Dr. Parker at Lakeside in June, 1919.

_Ursus americanus americanus._ Eastern black bear. Formerly occurred
in the region.

_Canis lycaon._ Timber wolf. About eleven years ago three were killed
from a pack of nine wolves at Lakeside. About 1910 a pack of eight
were seen at various times during the winter on the marsh between
Three Oaks and Galien. The following winter the same pack, or another
of the same number, was seen southwest of Three Oaks, and four of the
pack were killed just over the Indiana line.

_Vulpes fulva._ Eastern red fox. Common in the region. One was killed
in December, 1919, after having been chased from the Warren Woods by
dogs. Another was seen in January, 1920, half a mile north of Three
Oaks. In preceding winters a number have been killed south of Sawyer
where they evidently come from the sand dunes.

_Lutra canadensis canadensis._ Canada otter. Formerly occurred along
the streams, but are now apparently all gone.

_Felis couguar._ Cougar. One was killed a few miles northeast of Three
Oaks many years ago. Another was killed near New Buffalo in the early
days.

_Lynx ruffus ruffus._ Bobcat. One was killed a few years ago near the
Galien River a few miles northeast of Three Oaks.

_Erethizon dorsatum dorsatum._ Canada porcupine. Found here in the
early days.

_Sciurus carolinensis leucotis._ Northeastern gray squirrel. Black
squirrels were found in numbers in the early days.

_Glaucomys volans volans._ Eastern flying squirrel. Said to be common. A
large number were seen by Mr. Schmidt on one old stub in Warren Woods
some years ago. Several were seen in 1918 by Mr. Fox in second-growth
oak woods in a little ravine about one and one-fourth mile west of
Warren Woods. One was caught in Three Oaks in the fall of 1919.

_Cervus canadensis canadensis._ American elk. One horn from a large
swamp in Berrien County is in the Chamberlain Memorial Museum of Three
Oaks.

_Odocoileus virginianus borealis._ Northern white-tailed deer.
Formerly abundant in the region. Several molars were picked up in
Warren Woods.




FOSSIL MAMMALS OF BERRIEN COUNTY


The records of fossil mammals from Berrien County here published have
been collected by George R. Fox, who has also kindly loaned from the
collections under his care several specimens for identification. Dr.
E. C. Case assisted with the identification of the mammoth teeth.

_Mammut americanum._ Mastodon. (1) About 1897 the teeth of a mastodon
were dug up by a dredge within the village limits of Eau Claire. Their
disposition is unknown.

(2) At Snow, in section 36, Lake Township, a tooth was found. This
came into the possession of Frank Striker of Buchanan.

(3) A portion of a tusk and part of a skull were found on the Beebe
Farm near Baroda. These were sent to Washington, D.C.

(4) In the excavation of a ditch through a small marsh lying near
Bakerstown in Section 3, of Bertrand Township, the dredge uncovered in
the distance of between two and three miles bones, teeth, and other
evidences of six mastodons. Of these remains the most important was a
nearly complete skull with teeth in place and disintegrated parts of
the tusks. The skull was secured by Dr. E. H. Crane, who restored
parts, the tusks he did not attempt to restore. This skull is now on
exhibition at the Ward Museum, Rochester, New York.

The skull lay about seven feet deep. It was under a bed of matted oak
brush on top of which lay a huge stone slab, estimated to weigh two or
three tons. Above was a layer of silt, then gravelly clay; above were
more silt beds, three in number. W. Hillis Smith, who helped Dr. Crane
secure the skull, furnished the above information.

(5) On the Avery marsh, two miles east of Three Oaks, a badly decayed
mastodon skull and several teeth were excavated in 1884. Dr. Bonine,
Sr., of Niles, assisted at the excavation. The bones and teeth were in
the muck about twenty inches below the surface. Other teeth, making
seven in all, were found near the same place. Some of the teeth from
this locality are on exhibition at the Chamberlain Memorial Museum of
Three Oaks.

In addition to the above there are several indefinite records of
mastodon remains from the county.

_Elephas columbi._ Columbian mammoth. (1) One-half of the tooth of a
mammoth was found in the spring of 1917 on the Beeson and Holden farm in
Section 6, NE. 1/4, Township of Galien, by D. H. Beeson while
cultivating corn. Two weeks later the other half of the tooth was found.
The specimen is now in the Chamberlain Memorial Museum of Three Oaks.

The specimen is a well-worn lower third molar having twenty
ridge-plates, but some of the ridge-plates have been worn out and lost.
Seven and a half ridge-plates are included in a 100 mm. line. The
greatest length of the tooth is 280 mm. and its greatest breadth 95 mm.

(2) A complete set of mammoth teeth with some portions of the bones was
found about the year 1900 on a farm two miles southeast of Three Oaks
owned by E. K. Warren. They were discovered while digging post holes.
The specimens are on exhibition in the Chamberlain Memorial Museum.

One of the teeth sent us for identification proves to be a partly worn
lower third molar having twenty-four ridge-plates. There are seven and
a half ridge-plates in 100 mm. The greatest length of the tooth is 350
mm. and its greatest breadth 95 mm.

(3) There is another record of a mammoth tooth which was found at an
unknown location in Berrien County. It was at one time owned by Mr.
Smith, who gave it to Dr. Crane. Its present whereabouts is unknown.




PLATE I


A mud bar beside the Galien River in Warren Woods. A growth of mud-bar
herbs adjoins the flood-plain forest on the left. August 29, 1919.

Flood-plain forest in Warren Woods. There are few shrubs, but a
considerable amount of herbage is present. August 29, 1919.

[Illustration]

[Illustration]




PLATE II


Buttonbush swamp in Warren Woods. The swamp is surrounded by
flood-plain forest. August 29, 1919.

Climax beech-maple forest on the higher ground in Warren Woods. August
29, 1919.

[Illustration]

[Illustration]




Footnotes:


  [Footnote 1: L. R. Dice, _Occasional Papers, Mus. Zool._, No. 65.]

  [Footnote 2: Adolphe B. Covert, _Natural History--History of Washtenaw
  County_, p. 194. 1881.]




Transcriber's Note:


  *The footnotes have been moved to the end of the publication.