EXCHANGE

IOWA

Geological Survey

Bulletin No. 5

THE RODENTS OF IOWA

BY DAYTON STONER

GEORGE F. KAY, PH. D., STATE GEOLOGIST
JAMES H. LEES, PH. D^ ASSISTANT STATE GEOLOGIST

DES MOJNES:

PUBLISHED FOR IOWA GEOLOGICAL SURVEY
1918

vu

BARW

SCINC
UBRAitf

VES MOINES

ROBERT HENDERSON, STATE PRINTER
JOHN M. JAMIESON, STATE BINDER

I

LETTER OF TRANSMITTAL

IOWA GEOLOGICAL SURVEY

To Governor William L. Harding and Members of the
Geological Board:

Gentlemen: I submit herewith a bulletin on the Rodents of
Iowa which has been prepared by Mr. Dayton Stoner of the depart-
ment of Zoology of the University of Iowa.

The rodents are the most numerous and the most widely dis-
tributed of all the orders of mammals, and since all of them are
either herbivorous or omnivorous in diet they are of considerable
importance to the agriculturist. Some of them are harmful and
some of them are helpful in relation to crop production. It is
necessary, therefore, that the farmer and gardener be able to
discriminate between those rodents which are his friends and those
which are his foes. Of the thirty-one species of rodents of Iowa,
the most destructive species is the pocket gopher. Each year it
is responsible for a loss of half a million dollars to the crops of
the state.

The bulletin of Mr. Stoner describes the various rodents which
are found in Iowa, their general characters, habits, distribution,
economic importance, and the best methods of control of the most
destructive species and the proper methods for encouragement of
the most beneficial species.

Already the Iowa Geological Survey has published two bulletins
which deal with subjects of economic interest relating to the Nat-
•ural History of the state. One of these describes the Grasses of
Iowa and the other the Weeds of Iowa. Both have been of great
service to the people of the state. It is with the hope that the
bulletin on the Rodents of Iowa will prove to be of equal value to
the citizens of Iowa that it is now presented with the recommen-
dation that it be published as Bulletin 5 of the Iowa Geological
Survey.

I have the honor to be,

Yours sincerely,

George F. Kay,

State Geologist.

377996

GEOLOGICAL BOARD.

His Excellency, Wm. L. Harding Governor of Iowa

Hon. Frank S. Shaw Auditor of State

W. A. Jessnp President State University of Iowa

Raymond A. Pearson President Iowa State College

S. /W. Beyer President Iowa Academy of Science

ADMINISTRATIVE OFFICERS.

George P. Kay State Geologist

James H. Lees Assistant State Geologist

Nellie E. Newman Secretary

ILLUSTRATIONS

FIGURE 1. Map showing locality records of

1. Southern Flying Squirrel (Glaucomys volans volans) 18

FIGURE 2. Western Fox Squirrels a few days after birth. Photo from
life by Frank C. Pellett. From "Our Backdoor Neighbors.". 19

FIGURE 3. Western Fox Squirrels ten days after the previous picture w'as
taken. Photo from life by Frank C. Pellett. From "Our Back-
door Neighbors." 21

FIGURE 4. Map showing locality records of

1. Northern Gray Squirrel (Stciurus carolinensis leucotis).

2. Southern Red Squirrel (Sciurus hudsonicus loquax} 24

FIGURE 5. Map showing locality records of

1. Gray Chipmunk (Tamias striatus griseus) 28

FIGURES 6 AND 7. The Plains Prairie-Dog (Cynomys ludovicianus) .

(From U. S. Department of Agriculture.) 41

FIGURE 8. The Plains Prairie-Dog (Cynomys ludovicianus) .

(From U. S. Department of Agriculture.) 43

FIGURE 9. Plan of a iWoodchuck burrow. (From Field Museum of
Natural History.) 47

FIGURE 10. Pet Beavers. (From U. S. Department of Agriculture.) . 51

FIGURE 11. Northern White-footed Mouse (left). House Mouse (center).
Prairie White-footed Mouse (right). Photo from life by Frank
C. Pellett ." 53

FIGURE 12. The Brown Rat. (From U. S. Department of Agriculture,
Bureau of Biological Survey.) 54

FIGURE 13. Guillotine trap made entirely of metal. (From U. S. De-
partment of Agriculture, Bureau of Biological Survey.) 62

FIGURE 14. Guillotine trap with wooden base and trigger plate. (From

U. S. Department of Agriculture, Bureau of Biological Survey.)

63

FIGURE 15. Barrel trap: 1, with stiff paper cover; 2, with hinged cover;
a stop; & baits. (From U. S. Department of Agriculture, Bureau
of Biological Survey. ) 64

FIGURE 16. Map showing locality records of

1. Northern White-footed Mouse (Peromyscus leucopus novebora-
censis).

2. Prairie White-footed Mouse (Peromyscus maniculatus Txiirdi). 71
FIGURE 17. Field-Mouse skulls taken from pellets found under owl roost

in Smithsonian tower, Washington, D. C. (From U. S. Depart-
ment Agriculture, Bureau of Biological Survey.) 72

FIGURE 18. Prairie Harvest Mouse. Photo from life by Frank C. Pellett.

. 77

»

»* •* ' ** 1» * 9 ** * * > *> <)-*'*

ILLUSTRATIONS

FIGUEE 19. Meadow Mouse caught in a guillotine trap. (From U. S.

Department of Agriculture.) 79

FIGUKE 20. Map showing locality records of

1. Meadow Mouse (Microtus pennsylvanicus pennsylvanicus) .

2. Prairie Meadow Mouse (Microtus ochrogaster ochrogaster) .

3. Woodland Vole (Microtus pinetorum nemoralis) 81

FIGURES 21 AND 22. Apple trees1 five inches in diameter girdled by Prairie

Mice (Microtus ochrogaster). The trees were saved by heaping
up soil about the trunks to cover the injury. (From U. S. De-
partment of Agriculture, Bureau of Biological Survey.) 88

FIGUEE 23. Apple tree killed by Prairie Mice. (From U. S. Department of
Agriculture, Bureau of Biological Survey.) 89

FIGURE 24. Root and trunk of apple tree from Laurel, Maryland, gnawed
by Pine Mice. (U. S. Department of Agriculture, Bureau of
Biological Survey.) 92

FIGURE 25. Pine tree killed by Pine Mice. (From U. S. Department of
Agriculture, Bureau of Biological Survey.) 94

FIGURE 26. The Muskrat. (From U. S. Department of Agriculture,
Bureau of Biological Survey.) 98

FIGURE 27. Map showing locality records of

1. Goss's Lemming Mouse (Synaptomys cooperi gossii).

2. Prairie Harvest Mouse (Reithrodontomys megalotis dychei.) . .107
FIGURE 28. Faces of Pocket Gophers, showing pouches and incisors.

(From U. S. Department of Agriculture.) 109

FIGURE 29. Apricot tree killed by Pocket Gopher. (From U. S. Depart-
ment of Agriculture.) 112

FIGURE 30. A section of the Apricot tree sKbWn in the preceding view.
The injury was under ground. (From U. S. Department of
Agriculture. ) 113

FIGURE 31. Root of Apple tree gnawed by Pocket Gopher. Root knots
prominent. (From U. S. Department of Agriculture.) 114

FIGURE 32. Map showing locality records of

1. White-tailed Jack Rabbit (Lepus townsendi campanius.)

2. Great Plains Jack Rabbit (Lepus californicus melanotis.) 132

FIGURE 33. Young Cottontail at about the time of leaving nest. Photo

from life by Frank C. Pellett 134

FIGURE 34. Cottontail Rabbit in its "Form". (From U. S. Department

of Agriculture, Bureau of Biological Survey.) 135

FIGURE 35. Apple tree killed by Rabbits. (From U. S. Department of

Agriculture, Bureau of Biological Survey.) 136

FIGURE 36. Details of a Wellhouse Rabbit trap. (From U. S. Department

of Agriculture, Bureau of Biological Survey.) 138

CONTENTS

Introduction 13

Part I. Description of Iowa Rodents with Discussions of

Habits, Distribution, Economic Importance, Methods

of Control, etc 16

Gnawing Mammals, Order Rodentia 16

Squirrels4, Woodchucks, Spermophiles, etc 17

Southern Plying Squirrel 17

Western Pox Squirrel 19

Northern Gray Squirrel 22

Southern Red Squirrel 25

Chipmunk 26

Gray Chipmunk 27

Thirteen-lined Spermophile 29

Franklin's Spermophile 36

Black-tailed Prairie-dog 40

Southern Woodchuck 46

Beavers 50

Beaver 50

Rats and Mice 52

House Mouse 52

House Rat 54

Black Rat 68

Northern White-footed Mouse 69

Prairie White-footed Mouse 73

Prairie Harvest Mouse 76

Meadow Mouse . . . . 78

Prairie Meadow Mouse 87

Woodland Vole 91

Common Muskrat 9*6

Great Plains Muskrat 105

Goss' Lemming Mouse 106

Pocket Gophers 108

Pocket Gopher 108

Jumping Mice 122

Hudson Bay Jumping Mouse 122

Prairie Jumping Mouse 124

American Porcupines 125

Canada Porcupine 126

Hares and Rabbits 120

Minnesota Varying Hare 130

White-tailed Jack Rabbit 131

•$. » • Great Plains Jack Rabbit 133

Mearns^ Cottontail Rabbit . . 134

10 CONTENTS

Part II. Keys to the Suborders, Families, Genera and

Species of Iowa Rodents 141

Order Rodentia, Gnawing Mammals 141

Key to Suborders of Rodentia 141

Suborder Simplicidentata 141

Key to Families of Simplicidentata 142

Family Sciuridae, Squirrels, Woodchucks, etc 142

• Key to the Genera of Sciuridae 142

Subfamily Pteromyinse 143

Genus Glaucomys 143

Glaucomys volans volans, Southern Flying

Squirrel 143

Subfamily Sciurinse 143

Genus Sciurus 143

Key to Species of Sciurus 143

Sciurus carolinonsis leucotis, Northern Gray

Squirrel 143

Sciurus niger ruf iventer, Western Fox Squirrel 143

Sciurus hudsonicus loquax, Red Squirrel 143

Genus Tamias 144

Key to species of Tamias 144

Tamias striatus striatus, Chipmunk 144

Tamias striatus griseus, Gray Chipmunk , . .144

Subfamily Marmotinse 144

Genus Citellus 144

Key to Species of Citellus 144

Citellus franklini, Franklin's Spermophile 144

Citellus tridecemlineatus tridecemlineatus,

Thirteen-lined Spermophile 144

Genus Cynomys 145

Cynomys ludovicianus ludovicianus, Black-
tailed Prairie-dog 145,

Genus Marmota 14&

Marmota monax monax, Southern Woodchuck 145

Family Castoridse, Beavers 145

Genus Castor 146

Castor canadensis canadensis, Beaver 146

Family Muridae, Rats and Mice 146

Key to the Genera of Muridae 146

Subfamily Murinae 147

Genus Mus '. 147

Mus musculus, House Mouse 147

Genus Rattus 147

Key to Species of Rattus 147

Rattus norvegicus, Brown Rat 147

Rattus rattus, Black Rat 147

Subfamily Cricetinae lid

Genus Peromyscus 14&

Key to Species of Peromyscus 148

CONTENTS 11

Peromyscus maniculatus bairdi, Prairie White-
footed Mouse 14g

Peromyscus leucopus noveboracensis, Northern

White-footed Mouse .' 148

Genus R'eithrodontomys .148

Reithrodontomys- megalotis dychei, Prairie

Harvest Mouse 148

Subfamily Microtinae 148

Genus Microtus 148

Key to Species of Microtus 149

Microtus pinetorum nemoralis, Woodland Vole 149

Microtus ochrogaster ochrogaster, Prairie

Meadow Mouse 149

Microtus pennsylvanicus pennsylvanicus,

Meadow' Mouse 149

Genus Fiber . . ^ 149

Key to Subspecies of Fiber 150

Fiber zibethicus zibethicus, Common Muskrat ..150

Fiber zibethicus cinnamominus, Great Plains

Muskrat 150

Genus Synaptomys 150

Synaptomys cooperi gossii, Goss' Lemming

Mouse 150

Family Geomyidae, Pocket Gophers 150

Genus Geomys 150

Geomys bursarius bursarius, Pocket Gopher 150

Family Zapodidae, Jumping Mice 151

Subfamily Zapodinae 151

Genus Zapus 151

Key to Subspecies of Zapus 151

Zapus hudsonius hudsonius, Hudson Bay

Jumping Mouse 151

Zapus hudsonius campestris, Prairie Jumping

Mouse ' 151

Family Erethizontidae, American Porcupines 151

Subfamily Erethizontinae 151

Genus Erethizon . 151

Erethizon dorsatum dorsatum, Canada Porcu-
pine 152

Suborder Duplicidentata 152

Family Leporidae, Hares and Rabbits 152

Key to the Genera of Leporidae 152

Genus Lepus 153

Key to Species of Lepus 153

Lepus americanus phaeonotus, Minnesota

Varying Hare 153

Lepus townsendi campanius, White-tailed Jack
Rabbit . 153

12 CONTENTS

Lepus californicus melanotis, Great Plains

Jack Rabbit : 153

Genus Sylvilagus 153

Sylvilagus floridanus mearnsi, Mearns' Cot-
tontail 153

List of References 154

Index . 157

THE RODENTS OF IOWA

Introduction.

The present bulletin is offered to the people cf the state with the
object of giving such information as is available upon a group of
animals which is of considerable economic importance. The material
contained in Part I of the bulletin consists of brief diagnostic
descriptions of the various rodents known with certainty to occur
or to have occurred within the borders of the state, together with
something of their habits, distribution, economic importance and
also methods of control where such are deemed desirable. Most of
the measurements included in the descriptions are given in
inches. To avoid small and inconvenient fractions of inches
some small measurements are given in millimeters, a millimeter be-
ing equivalent to approximately 1-25 of an inch. The measure-
ments given for the various forms indicate the average; so that
specimens may be found which are somewhat below or above the
figures indicated. These measurements are taken in the follow-
ing manner:

Total length. — Distance from tip of nose to tip of tail vertebrae
not including the hairs.

Tail vertebrae or tail. — Distance from the point where the tail
joins the body to tip of tail, not including the hairs.

Hind foot. — Distance from heel to end of longest claw.

In order to facilitate ready determination of groups and species,
simple keys based, for the most part, upon external characters are
added, and will be found in Part II of the bulletin. It is- hoped
that these identification tables will be found useful to individuals
as well as in schools where study of this nature can profitably be
taken HD, and it is further hoped that this paper may be of service
in creating among the people of the state a greater interest in the
wild life about them.

The entire paper has been prepared with special reference to
the needs of the lay public, and an attempt has been made to make-
it as non-technical as possible without sacrificing too much that is;
seriously and strictly scientific.

A further attempt has been made to give special consideration
to those rodents which are of economic importance to us. Any

14 RODENTS OP IOWA

animal is worthy of consideration from an economic standpoint
if it is sufficiently abundant and is in some way or other detrimental
to man's best interests. Nature seeks to maintain a proper "bal-
ance" among all the forms of life on the globe, but when man
steps in and interferes with this great plan some penalty must often
be paid. When the numbers of any species of animal are main-
tained at about the normal, the damage done is so slight as to be
almost negligible. If, however, the numbers of any species, through
some cause or other, reach a point far above normal, their habits
and even their presence make them worthy of consideration. The
kind and quality of the food destroyed are matters rather of sec-
ondary importance. Since many of the rodents are prolific breed-
ers and most of them are also hearty eaters, methods of control
and remedial measures of various kinds are often of considerable
value.

In the main, the system of classification and arrangement of
species here adopted is that employed by Cory in "The Mammals
of Illinois and Wisconsin."1 In some cases, however, a later sys-
tem has been followed. Attempt has not been made to include all
the forms which "possibly" or "probably" occur within the
state, but for the most part, only those appear of which certain
and authentic records are available. For this reason and because
of the fact that many of the species have been split up into a
greater or lesser number of subspecies and geographic races, it is
possible that some forms not mentioned in these pages should be
added, but the main object of the paper will not have been de-
feated on this account. In the preparation of this bulletin data
have been drawn freely from Cory's work and from the various
papers published by the United States Biological Survey. Other
articles which have proved of value are included in the list of
references. Under every species and subspecies reference is given
to the first publication of the specific or subspecifie name.

During the preparation of the present work various parts of the
state have been visited for the purpose of observation and the se-
curing of material. In addition, the assistance of others has been
invited, so that the list of those who have contributed in some way
or other is rather a long one. The following persons have thus
aided materially in the securing of specimens from which many
localitv records were obtained:

1Cory, Charles B.. The Mammals of Illinois and Wisconsin : Field Mus. Nat.
., Pub. 153, Zool. Ser. XI, 1912.

INTRODUCTION 15

J. K. Alter, Wayland; *B. H. Bailey, Cedar Rapids; Paul Bau-
man, Melvin; Virgil Bearden, Thayer; Merrill Deal, Waukon; H.
R. Dill, Iowa City; Kenneth Dunlop, Jefferson; Marcus Fiene,
Ocheyedan; Joe Gibson, Corning; Porter Green, Garrison; San-
ford Griswold, Charles City; W. P. Kubichek, Iowa City; J. R.
Martin, Tama; Marion Mincks, Ottumwa; Henry Schroeder, Yin-
ton; J. A. Spurrell, Wall Lake; A. 0. Thomas, Iowa City.

Specimens have been examined in the Museum of the State Uni-
versity of Iowa, the Coe College Museum, the Grinnell College Mu-
seum, and the Iowa State Museum at Des Moines. The sources of
other material and information are given in the text.

In addition, data of various kinds have been obtained from
farmers, hunters, and trappers while the county auditors of the
various -counties visited have given information and notes on
bounties. All have been uniformly courteous and sympathetic.

Determinations of specimens have been made and verified by
officials of the United States Biological Survey through the cour-
tesy of Mr. E. W. Nelson, Chief of the Survey. Various points
of difficulty have, from time to time, been referred to workers in
the Survey, and the response has always been prompt and grat-
ifying. Certain of the figures herein published have also been
furnished by the Division of Publications, United States Depart-
ment of Agriculture.

Mr. Frank C. Pellett of Atlantic has furnished notes, specimens,
and data relating to some of the forms discussed ; and several of the
photographs herein included are the result of his work.

Miss Jane E. Roberts, Librarian at the State University of
Iowa, has made it possible for me to have access to various books
and papers not found in the University Library, but which were
essential to the prosecution of this work.

Especial thanks are due Professors C. C. Nutting and H. F.
Wickham, of the Department of Zoology, State University of Iowa,
for helpful suggestions and criticism during the preparation of
this paper.

Dr. James H. Lees, Assistant State Geologist, has offered sugges-
tions and granted many courtesies.

To Professor G. F. Kay, Director of the Iowa Geological Sur-
vey, I desire to express my appreciation for having made possible
this bulletin and for continued encouragement and interest during
its preparation.

*Deceased.

16 RODENTS OF IOWA

PART I.

DESCRIPTIONS OF IOWA RODENTS.

GNAWING MAMMALS.

Order RODENTIA.

The order Rodentia is the largest and most widely distributed
of the mammalian orders; and, due to the fact that all the members
are either herbivorous or omnivorous in diet, it forms a group of
considerable economic importance, especially to the agriculturist.
In such a large group as this it is but natural to expect great va-
riety in form and habits. Some, such as the muskrat, are semi-
aquatic; others, such as the pocket gopher and the spermophiles,
are more or less fossorial and live in underground burrows; still
others, such as the squirrels, are arboreal; while many representa-
tives of the group are terrestrial.

In spite of this great diversity in habits, certain peculiarities are
characteristic of the group. A rodent may at once be distinguished
from any other mammal by the large, clAsel-like front teeth (in-
cisors) , the absence of canines, and the long toothless space between
the incisors and the molar series. There is never more than a
single pair of lower incisors; and in only one group, the Duplici-
dentata, the suborder containing the hares, rabbits and their allies,
is the number of upper incisors greater than the lower. In the
Duplicidentata a second pair of small incisors is found situated
immediately back of the large normal front pair. Due to the fact
that these incisor teeth are furnished with enamel on their an-
terior faces and also that these teeth continue growing as they be-
come worn away, a sharp, chisel-like edge is maintained which is
very effective in cutting. Both upper and lower incisors are regu-
larly curved, the curvature of the upper pair being somewhat
greater than that of the lower pair although the tips of these teeth
oppose one another.

The mouth is divided into two cavities which communicate by a
constricted orifice in the space between the incisor and molar teeth,
so that the two cavities each contain one of these sets of teeth;
the hairy skin of the face is continued inward behind the incisors.
Such an arrangement prevents substances not intended for food

SOUTHERN FLYING SQUIRREL 17

from being taken into the mouth, and is thus effective when the
possessor is gnawing some obstruction.

Thirty-one forms of rodents have been recorded from Iowa and
are discussed in this paper. These represent six families, five of
which belong to. the suborder Simplicidentata.

SQUIRRELS, WOODCHUCKS, SPERMOPHILES, ETC.

Family SCIUR!D>E.

This is a family of wide distribution and high specialization,
and in Iowa some of the forms are so abundant and destructive
as to be worthy of consideration in their economic relations. They
vary in form and habits from the arboreal flying squirrel fitted for
semi-aerial progression, to the terrestrial and fossorial woodchuck.
Some forms hibernate in our latitude. Many of the forms are
more or less brilliantly colored, reds, yellows, and browns predom-
inating.

SOUTHERN FLYING SQUIRREL. FLYING SQUIRREL.
Glaucomys volans volans (Linnaeus).

[Mus] volans Linnaeus, Syst. Nat., X ed., I, 63, 1758.

Description. — Upper parts grayish or grayish brown, more or
less shaded with russet, with the upper surface of tail slightly
darker ; most of the upper surface of flying membrane dark brown ;
under parts white, the hairs entirely white at the bases; under
surface of tail buify or buffy white ; fur very smooth and soft. In
winter, the coloration is similar, but the upper parts are more
deeply tinged with grayish brown.

Measurements. — Total length, 9.25 inches, tail vertebrae, 3.90
inches; hind foot, 1.20 inches.

Habits, Distribution, Etc. — This little squirrel seems to be fairly
common in rather heavily wooded areas throughout the state, but
is more abundant in the eastern half. It is not often seen by the
average person because of its nocturnal habits, though it sometimes
comes out in late afternoon. One of its common methods of progres-
sion is to climb to the top of a high tree and then to launch forth
into the air when, by means of the expanded integument at the sides
of the body, it is able to glide to the lower branches or trunk of a
tree often some distance away. And thus the animals, while they
.are not able to "fly" can glide from a higher to a lower point.

18 RODENTS OP IOWA

Flying squirrels are more or less gregarious and make their
nests of moss and leaves in hollow trees. Often, when such a tree
is disturbed, several of these little gray fellows will scamper out
and sail away to another tree. Many abandoned red-bellied or
red-headed woodpeckers' nests are inhabited by families of these
squirrels, and a single tree may contain several families. The young
are from four to six in number and are said to make interesting
pets.

Contrary to some observations it is not probable that flying squir-
rels really hibernate during the winter, although they do remain
in their nests during severe weather; but their sleep is easily
broken, and upon being aroused from the nest they are apparently
as active as ever.

The food of flying squirrels consists for the most part of seeds,,
nuts, acorns, corn, insects, and sometimes of birds' eggs and even
of the young birds themselves. However, they >can scarcely be said
to l*e sufficiently plentiful in any locality to cause serious harm
and should not be slaughtered indiscriminately. Neither should it
be considered good form to hold as captives and merely for the
amusement of the possessor any of these handsome little animals.

FIG. 1. — Map showing locality records of —

1. Southern Flying Squirrel (Glaucomys volans volans).

Specimens are at hand from the following localities : Iowa Cityr
Wayland, Knoxville, Wall Lake, Ft. Dodge, Iowa Falls, Humboldt,
Moscow, Steamboat Rock, Dubuque, Thayer, Colfax, Cedar Rapids,

WESTERN F'OX SQUIRREL

19

In early days, according to the best information obtainable, this
species was 'common in many localities where it is now scarce.
Towards the extreme western part of the state the species is re-
ported as rare or absent. With the cutting off of the heavily tim-
bered areas in many parts of the state the distribution of the flying
squirrel has become much more restricted than formerly and its
numbers have correspondingly diminished.

WESTERN FOX SQUIRREL. FOX SQUIRREL.
Sciurus niger ruftventer (Geoffroy).

Sciurus rufiventer Geoffroy, Cat. Mamm. Mus. d'Hist. Nat.. 176,
1803.

Description. — General color, upper parts tawny brown with
darker brown intermingled; tail mixed black and rufous, the tips
of the hairs tawny or rufous ; ears rufous brown ; under parts pale
rufous or yellowish brown.

FIG. 2. — "Western Fox Squirrels a few days after birth. Photo from life by
Frank C. Pellett. From "Our Backdoor Neighbors."

Measurements.— Total length, 22.00 inches; tail vertebrae, 9.75
inches; hind foot, 3.00 inches.

20 RODENTS OP IOWA

This is a very variable form and one for which a single descrip-
tion will not fit every specimen. Some individuals are entirely
black, while others present a mixture of rufous and tawny with
all sorts of intermediate variation. Usually, however, the color
above is tawny gray-brown with yellow or pale orange below ; the
hairs of the tail are rufous more or less mixed with black, usually
tawny or rufous at the tips and with the under surface bright
ferruginous. The gray squirrel is the only other Iowa form which
is likely to be mistaken for the present species, which may at once
be distinguished from that form by the tawny or rufous tips to
the hairs on the tail and- the presence of but four teeth of the molar
series on each side of both jaws. In addition, the gray squirrel
averages about three to four inches smaller than the present species.

Habits, Distribution, Etc. — This the largest of our arboreal squir-
rels inhabits the more or less heavily timbered districts of the state
and is much less often found in open ground. It has become abun-
dant in many of our parks and even on the lawns in cities, where
its antics afford interesting diversion for many people. It is a
more solitary species than the gray squirrel, and seldom are more
than two adults found living together. Usually in the summer and ;
fall the old males go about by themselves. The fox squirrel often
builds several nests, usually in tall trees but in some cases not
more than fifteen to twenty feet from the ground. These nests
are composed of leaves and sticks placed in the fork of the tree.
The nest materials are usually cut from the tree in which the nest ;
is made, although adjoining trees may be visited for the securing
of this material. After the young are able to shift for themselves
they either leave the nest of their own accord or are driven away
by the mother, and for a time lead more or less of a wanderer's
existence, building nests for themselves as the occasion arises and
perhaps abandoning them again in a short time. Sometimes the;
fox squirrel chooses a hollow tree as an abode -; but it does not re-
quire such a domicile in Avhich to rear its young, as the author has |
personal knowledge of young being reared in nests composed of
leaves and twigs. Usually two or three young are produced at one
birth although the number varies from one to five. The young are i
born blind and naked and do not assume a squirrel-like appearance
until about three weeks old. It seems probable that in some in-
stances two litters are brought forth in a season.

WESTERN FOX SQUIRREL

21

The food of the fox squirrel is composed of nuts', acorns, seeds,
and the buds of trees, particularly of maple and elm. In late sum-
mer and early fall it eats the fruit of various thorn and berry bushes
and sometimes also destroys insects. It has been observed to gnaw
the bark from dead trees in order to secure beetles and their larvae.
In cities and towns where the food supply is rather limited it
sometimes visits granaries and destroys or carries away consider-
able grain. The writer has seen an adult squirrel while carrying
a good-sized ear of corn, ascend a tree without much difficulty.
In many localities this squirrel has been reported as destroying
birds' nests and eggs; and while there is some evidence to corrob-
orate this, the habit does not seem sufficiently widespread and seri-
ous to require drastic measures of control. Sometimes by eliminat-
ing a single pair of squirrels or even a single individual from a
restricted locality the difficulty will be solved.

FIG. 3 — Western Fox Squirrels ten days after the previous picture was taken.
Photo from life by Frank C. Pellett. From "Our Backdoor Neighbors."

In Dubuque county a member of the board of supervisors in-
formed the writer that this species destroyed about five acres of
growing corn on one farm where the shooting of these rodents was
prohibited. However, this is the only instance of serious damage
by this animal to which the writer's attention has been called.

RODENTS OF IOWA

The fact has also been pointed out by some, that "squirrels,"
probably including the present species, seek out and feed upon
acorns in which living larvae of the Oak Weevil (Balaninus sp.)
are developing. In such cases the fox squirrel, along with others,
acts as an element in the control of this insect pest. Considering
its habits in general, this squirrel should be protected and encour-
aged to nest in our parks and woods ; and the toll that it may exact
in the destruction of a few birds must be included in the great
scheme of Nature for maintaining a proper balance among animals.

The fox squirrel is reported as common or abundant by observ-
ers in practically all parts of the state, but the numbers diminish
somewhat towards the extreme western and eastern portions. In
almost any locality where the woods are not too dense these animals
are most abundant. Of late years a general sentiment toward the
protection of this species has sprung up with the result that in
our public parks and even along city streets which are fairly well
furnished with shade trees the fox squirrel is not uncommon and
often breeds. In eastern Iowa, particularly in northeastern Iowa,
considerable tracts of dense woodland still remain, and such are
not frequented so much as are the central prairie woodlands.
Thence toward our western border even sparsely wooded areas are
much less frequent, so that this feature of the topography also
seems to have some effect upon the distribution of this animal.
John Spurrell of Wall Lake writes that this form first appeared in
that locality about 1904, so that the wave of dispersal seems to be
towards the west. At Sibley, in Osceola county, this form is re-
ported to have appeared only within the last three years.

If a list of locality records were prepared for this species it
would probably include every county in the state so that a com-
plete record would seem superfluous. It has been reported in prac-
tically all of the sixty-two counties visited during the preparation
of this paper. Specimens are at hand also from many localities.

NORTHERN GRAY SQUIRREL. GRAY SQUIRREL.

Sciurus carolinensis leucotis (Gapper).
Sciurus leucotis Gapper, Zool. Journ., V, 206, 1830.

Description. — Summer: General color above grayish with a faint
tinge of brownish along middle of back, at the sides of the body
just behind front legs, on the ears and about the head and face;
under parts white or whitish, sometimes with a rusty tinge on back

NORTHERN GRAY SQUIRREL 2Z

and chest; hairs of tail yellowish at base followed by blackish and
tipped with white. Winter: Above silvery gray, the bases of the
brown hairs on the head entirely or almost concealed.

Measurements. — Total length, 19.75 inches; tail vertebrae, 9.00
inches ; hind foot, 2.70 inches.

This is another form which varies markedly in color from en-
tirely black to gray with many intergradations ; sometimes also
albino specimens are found. In the Museum of the State Univer-
sity of Iowa is a mounted specimen with the under parts and sides
of the head entirely black. This squirrel may be separated from
its closest ally in our fauna by the fact that it usually possesses five
teeth of the molar series on either side of the upper jaw; two of
these teeth are premolars and three are molars; in addition, the
hairs of the tail are tipped with white.

Habits, Distribution, Etc. — The northern gray squirrel seems to
prefer the more heavily wooded regions of the state, and towards
the extreme east and northeast is reported as more common than
the fox squirrel. In these regions densely timbered areas are not
uncommon, while farther west many of the extensive timbered
sections have been destroyed and along with them the gray squir-
rels. At Ottumwa and Albia this species was formerly rather
abundant, but the numbers have been much lessened of late, as the
miners have killed a great many for food.

It is seldom that in restricted localities tlie gray squirrel and
the fox squirrel are found in equal numbers, the advantage in this
respect being usually with the former. The gray squirrels are
the more pugnacious of the two and will not tolerate the presence
of the fox squirrels, making life so miserable for them that they
soon abandon the locality.

This is one of the more gregarious species of our arboreal squir-
rels and considerable numbers of them in some instances occupy a
limited area. In early days the species was more or less migra-
tory; but while it may at the present time migrate somewhat, the
numbers have been so greatly reduced that attention is not directed
to the phenomenon. These migrations occurred at irregular inter-
vals and were probably undertaken for the purpose of securing
a more adequate food supply.

The northern gray squirrel nests in hollow trees and in habita-
tions constructed of leaves, twigs, and bark which are placed
amons: the branches. These exterior nests have a roof and an en-

24

RODENTS OF IOWA

trance from the side. In many cases two litters of young are pro-
duced in a season, the first usually early in April and the second
in late August or early September. A litter usually consists of
from three to five young, which are born naked.

Although this squirrel remains in a quiescent or semi-dormant
condition often for long periods of time during severe winter
weather, it does not hibernate in the true sense of the word. When
weather conditions become more favorable it comes out, runs about
and feeds, and upon the appearance of another period of cold
again enters its nest.

The food of the gray squirrel is very similar to that of the fox
squirrel and both indulge in the same habit of burying nuts and
acorns in holes in the earth. It is not probable that squirrels "re-
member" where the morsel has been placed, but probably depend
upon a keen sense of smell for again finding the buried nuts. Some-
times they burrow beneath the snow to reach the buried food, while
many times, no doubt, they never appear again at the spot where
a nut or acorn has been hidden.

FIG. 4. Map showing1 locality records of —

1. Northern Gray Squirrel (Sciurus carolinensis leucotis).

2. Southern Red Squirrel (Sciurus hudsonicus loquax).

The northern gray squirrel is reported as abundant nowhere in
the state except in the northeastern portion. At Waukon, Mc-
Gregor, and Dubuque it is more abundant than the fox squirrel. In
localities farther to the west individuals are met with occasionally,

SOUTHERN RED SQUIRREL 25

but with the cutting over of the heavily timbered areas and the
more or less wanton destruction of these animals the numbers
are becoming much reduced. At Iowa City this form is much less
common now than fifteen years ago. Towards the southcentral
part of the state it is seldom seen while towards the northwest in
Clay county it is reported as fairly common. Other localities
from which specimens have been sent or where the species is re-
ported as being at least common are: Muscatine, Oxford, Monti-
cello, Fort Dodge, Paralta, Des Moines, and Osage.

SOUTHERN RED SQUIRREL. RED SQUIRREL.
CHICKAREE.

Sciurus hudsonicus loquaa (Bangs.)

Stiurus hudsonicus loquax Bangs, Proc. Biol. Soc. Wash., X,
161, 1896.

Description. — Summer: Upper parts reddish brown ; a conspicu-
ous black lateral stripe separates the color of the back from the
white under parts, which on some specimens are tinged with rusty ;
tail mostly deep rufous brown, the terminal hairs blackish at tips;
front of fore legs and upper surface of hind feet yellowish. Winter:
A broad median dorsal stripe of bright rufous brown or orange
rufous extends from between ears to tip of tail; sides olive gray;
lateral stripe wanting or but faintly indicated; under parts gray-
ish white; under surface of tail olive gray, the hairs on the sides
and tip of tail with a subterminal band of black and tipped with
tawny. Soles of feet furred.

Measurements. — Total length, 12.50 inches; tail vertebras, 5.00
inches; hind foot, 1.85 inches.

In summer the red squirrel is of a reddish brown color with
the under parts white or grayish white, while in winter the upper
parts are grayer with the bright rufous stripe down the back and
the under parts also grayer. The tail is somewhat flattened;
in winter the ears are tipped with long hairs, and the soles of the
feet bear soft hair.

Habit's, Distribution, Etc. — The red squirrel is most at home
in the well wooded areas of the eastern half of the state, but
occurs also though not so commonly in the forests of western Iowa.
Usually it makes its home in a hollow log or tree, but sometimes a
deserted woodpecker hole is chosen for a habitation. In rare

2« RODENTS OF IOWA

cases it makes its nest in a hole in the ground and in perhaps equally
rare cases it constructs a nest of leaves and twigs among the
branches of trees. Although it does not hibernate in winter, it is
not active during severe weather; when the temperature has mod-
erated somewhat, even though the ground is covered with snow,
it comes out as usual.

Usually four or five young are produced at a single birth ; they
are born in April.

The red squirrel may be classed as an almost omnivorous feeder,
but it is seldom so abundant in any locality as to cause serious
damage to stored food or grain. In places where it is abundant,
it may make rare attacks on cornfields which are planted along the
edges of woods, but the writer has heard of no damage of this sort
in the state. Among the kinds of food of which it is particularly
fond may be mentioned acorns, nuts of various kinds, wild fruits
and berries, mushrooms and insects; birds' eggs and sometimes
even their yqung are eaten. Many other things might be included
in the list. In autumn this squirrel stores away quantities of
acorns, nuts, seeds, etc., for use during the winter and in some
localities it is reported to have carried off the stores and food of
both the fox squirrel and the gray squirrel.

While this form is found more particularly in the eastern half
of the state, its distribution is not thus limited; for it may be
met with in almost every wooded area of any size within the borders
of the state. Towards the south it seems to be much less common
and here the wooded areas are also much less limited in extent.
Among the definite locality records may be mentioned Clear Lake,
Knoxville, Iowa City, Lake Okoboji, Charles City, Atlantic. See
also the map on page 24.

The Minnesota chickaree (Sciurus liudsonicus minnesota Allen),
formerly considered a valid geographical race has now been proved
to be only a lighter color phase of the red squirrel and hence is not
included in this paper.

CHIPMUNK. STRIPED CHIPMUNK.
Tamias striatus striatus (Linnaeus).

[Sciurus] striatus Linnaeus, Syst. Nat., X ed., I, 64, 1758.
Description. — Upper parts rusty brown with flanks and limbs
pale yellowish brown; deep chestnut rufous on the rump; back

GRAY CHIPMUNK 27

with five black stripes, the median one bordered by chestnut
brown ; a yellowish white stripe on either side of the back separat-
ing the two lateral black stripes; under parts white or whitish;
tail rufous margined with black.

Measurements. — Total length, 9.60 inches; tail vertebrae, 3.75
inches; hind foot, 1.25 inches.

This is one of the smaller members of the family and is further
characterized by the flattened and only slightly bushy tail, the
striped back and the chestnut rufous rump; it is also smaller than
its nearest ally, T. s. griseus.

It is probable that many records of this species in the state
may be referred to the following form and that the two have been
often confused. The exact status of these forms is not yet defi-
nitely known. In habits and general characteristics the present
form is very like T. s. griseus. A single specimen in the Coe Col-
lege Museum, collected at Traer, June 23, 1902, and another col-
lected at Iowa City are the only two definite locality records
which are available. Reports from different parts of the state
indicate that " chipmunks" are becoming less common; and this,
no doubt, is due to the clearing of many of the timbered areas
for agricultural purposes. Damage from this or the following
species has not been reported.

GRAY CHIPMUNK. GRAY STRIPED CHIPMUNK.
Tamias siriatus griseus Mearns.

Tamias striatus griseus Mearns, BulL Am. Mus. Nat. Hist., IIIr
231, 1891.

Description. — Very similar to Tamias striatus striatus but grayer
and larger; lower back and rump cinnamon brown; back with five
black stripes between which the color is distinctly gray; under
surface of tail paler and the hairs of the tail tipped with gray.

Measurements. — Total length, 10.25 inches; tail vertebrae, 4.15
inches; hind foot, 1.45 inches.

This form varies somewhat in color and in measurements, those
indicated above being the average, and variations of a half
inch above or below those given may occur. It may be distin-
guished from the preceding form by its larger size and by the
darker color of the rump. Intermediates are likely to be met
with, particularly in northeastern Iowa, but most of the Iowa
specimens seem to be referable to T. s. griseus.

28

RODENTS OP IOWA

Habits, Distribution, Etc. — The gray chipmunk is more terres-
trial in its habits than any of the species of squirrels which have
been discussed and it is usually found in rocky, wooded areas
grown up in underbrush and about old logs or buildings which
are surrounded by growths of bushes and weeds to offer con-
cealment. Sometimes it ascends large trees, but for the most part
it contents itself with climbing about logs, rocks, and fences and
in this art it is very expert. During the summer it industriously
stores up grain, seeds, nuts, etc., for food during the winter.
These materials are carried to its home, which is usually an under-
ground burrow among loose rocks or under a decaying log or
stump. In addition to these things it subsists to some extent
upon young mice, birds, and small snakes.

While the gray chipmunk does not truly hibernate during the
winter, it remains quiescent for longer or shorter periods of time
during severe weather; when the weather moderates, even though
there is snow on the ground, it comes forth and disports itself
in its accustomed manner. In many cases, however, on the ap-
proach of cold weather it enters its burrow not to reappear until

FIG. 5. — Map showing locality records of —

1. Gray Chipmunk (Tamias striatus griseus).

the signs of early spring have tempered the surroundings. These
little animals afford interesting diversion for the observer if they
are allowed to come about buildings, and the writer has never

STRIPED SPERMOPHILE 29

heard of any damage being attributed to them, beyond the carry-
ing away of a few nuts. This chipmunk is somewhat sociable and
more or less gregarious; sometimes several pairs apparently oc-
cupy the same burrow during the winter. The young are usually
four or five in number and are born blind and naked.

When the animal is undisturbed it utters a sort of dull cluck
which may be repeated many times, but when it is disturbed a
series of rapid shrill chips is often given.

Of the two chipmunks found in the state this seems to be much
the more abundant, and the writer has found that in most cases
where "chipmunks" are reported, reference is made to this form.
It seems to be quite generally distributed over the state and
is reported as common or fairly common by nearly all observers.
In many localities, however, it is reported that the numbers are
rapidly decreasing. At the Iowa Lakeside Laboratory it is1 quite
common in the surrounding woods, and in the summer of 1916
half-grown young were much in evidence during the first half of
July. At Iowa City this form as well as the preceding one seems
to be present. Other definite locality records for the present spe-
cies are: McGregor. Cedar Rapids, Des Moines, Wayland, Charles
City, Thayer.

THIRTEEN-LINED SPERMOPHILE. STRIPED SPERMO-
PHILE. THIRTEEN-LINED GROUND SQUIRREL.
STRIPED GROUND SQUIRREL.
STRIPED GOPHER.

Citellus tridecemlineatus tridecemlineatus (Mitchill).
Sciurus tridecem-lineatus Mitchill, Med. Repos., N. S., VI, 248, 1821.

Description. — Color above dark brown, varying from chestnut
to nearly black ; back with seven yellowish white lines which alter-
nate with six rows of rounded yellowish white spots in a back-
ground of brown; below pale tawny brown; tail comparatively
short and not bushy; middle of tail brown and white bordered by
an inner stripe of black, the ends of the hairs forming the fringe
buffy white; a pale ring around the eye.

Measurements. — Total length, 10.50 inches; tail vertebrae, 3.75
inches; hind foot, 1.35 inches.

This animal-, which possesses an unusually large number of local
names, while somewhat squirrel-like in appearance, is the more
slender of our two spermophiles and the tail is comparatively short

GO RODENTS OF IOWA

and not bushy. The chipmunk (Tamias striatus griseus) is some-
times -confused with this species; but the chipmunk inhabits the
forests and climbs trees, while the striped spermophile is found
on the prairies and does not climb trees. The chipmunk has no-
spots and is further characterized by a more bushy tail and longer
ears. Albino specimens of the striped spermophile are occasion-
ally met with.

The word spermophile by which this and the following species
are properly known is derived from the Greek words meaning
"seed" and "to love," and refers to the propensity of these
animals for eating seeds, which, indeed, form a large part of
their diet.

Habits, Distribution, Etc. — This is more particularly a prairie
form inhabiting the open fields practically throughout the state,
and scattered colonies may be seen in 'almost any locality not too
densely wooded. Often they are found along the edges of timber
or groves. The animals are gregarious and diurnal, and during
the summer months one often hears their whistle as they scamper
through the fields or away from the roadside.

The striped spermophile obtains shelter and protection in bur-
rows which it digs in the ground. These burrows, which are
usually made in pastures, along fences and rights of way of
railroads, and in other uncultivated places, are about two inches
in diameter; they descend abruptly for a short distance and then
extend horizontally. Many of the tunnels are short and used
simply for safe hiding places when danger approaches. The tun-
nels leading to the nests where the animals spend the winter and
rear their young are often fifteen to twenty feet in length and
from one to two feet beneath the surface. The entrance to the
burrow is sometimes on the bare ground, sometimes hidden by
a tuft of grass.

In the fall the spermophiles become very fat and after a few
nights of frost and before the ground freezes they disappear
within the burrows not to reappear until the ground thaws in the
spring. Competent observers state that these animals hibernate
in the true sense of the word for the bodily processes are so feeble
that a few degrees below freezing is sufficient to actually cause
death. With the thawing- out of the ground in the spring the
animals issue forth, and the young are usually produced in late
May or early June. The number of young in a litter varies from

STRIPED SPERMOPHILE 31

seven to ten. They are naked and blind when born and require
a longer period of care by the mother than is usual in rodents.
In late June and during July when the half-grown young appear
above ground the voices of these animals are most frequently
heard, the mother and young constantly calling back and forth;
during the breeding season the adults are shy and quiet. In the
summer the young begin to dig shallow burrows and before fall
leave the mother to shift for themselves.

Adults of this species are at times quite pugnacious and often
engage in fierce battles among themselves, scarred faces and ears
and lost tips of tails apparently being the most serious results of
such encounters. One observer reports having seen a male of
this species kill a weasel in a fair fight by biting entirely through
the weasel's skull.

The striped spermophile is widely distributed through the cen-
tral part of North America, and in Iowa is common or abundant
in practically every locality visited. It is found generally through-
out the state and is much more widely distributed than Frank-
lin 's spermophile ; in most localities it is more abundant than that
species, and its local range is also less restricted.

Food Habits, Economic Importance and Control Measures. — As
above indicated, the name spermophile means seed lover and
scarcely a grain or seed grows where these animals are found
that they do not eat. Among the cultivated seeds eaten are wheat,
barley, oats, corn, rye, and millet, but their diet is not restricted
to these cultivated seeds alone for they are also fond of various
cultivated fruits and roots. In addition, acorns, hazelnuts, seeds
of pigweed, bindweed, knotweed, pigeon grass, and ragweed make
up a goodly share of their food. Nor is their diet confined to the
vegetable world; for animal food makes up a part of their diet
and they feed particularly on various insects such as grasshop-
pers, beetles, caterpillars, and ants. ''Of the total contents of
eighty stomachs examined, more than half consisted of insects.
The percentage of animal matter was 52.9 ; of vegetable matter
44.4; and of undetermined matter 2.7. The cheek pouches con-
tained 100 per cent of vegetable matter, being filled exclusively
with grain and seeds of various plants."2 Since this species is
so abundant and widely distributed in the state and because of
the nature of its food it has gained an evil reputation among
farmers. In addition to destroying the cultivated seeds above

*U. S. Dept. Agr., Bull. No. 4, 43, 1893.

32 RODENTS OP IOWA

mentioned observers everywhere report that it pulls up and eats
newly planted corn and other seeds. This is especially true if the
cultivated field adjoins a pasture or uncultivated area such as
is frequently inhabited by these animals. Often the outer five or
six rows of newly planted <corn are pulled up and destroyed.
While the striped spermophile destroys insects of various kinds
it does not exercise any qualities of discrimination and beneficial
as well as harmful kinds are eaten. On the whole therefore it
cannot be said to be of value to the farmer. Vernon Bailey says :
(1. c., p, 42.) "Undoubtedly the good which the Striped Spermo-
philes do by destroying insects, and seeds of noxious weeds is of
no small importance but it is doubtful if it is sufficient to offset
the damage perpetrated by them in grain fields. In many local-
ities it is impossible to raise a full field of corn without first
killing the spermophiles. As soon as the corn is planted they
begin to dig up the seed but do most mischief after the corn begins
to come up and until it is a week or ten days old, or until all the
nutriment is drawn from the grain. They dig down by the side of
the stalk and" eat the swollen, starchy grain, of which they seem
very fond, leaving the stalks to die. As a single spermophile will
dig up many hills of corn in a day and continue digging for
nearly two weeks, it is not difficult to see that serious damage
is done where they are numerous, averaging as they often do
four or five to an acre. Large fields of corn are entirely de-
stroyed by them and have to be planted over several times. A
great deal of wheat, oats, barley and rye is taken in the same
way making it necessary to sow an extra amount of seed. Even
this means is not effectual, and frequently fields of sowed grain
suffer materially from their attacks. As .the small grains begin
to fill soon after blossoming the spermophiles cut down the stalks
and eat the ovules, and in order to find the best heads they cut
down a great deal more than they eat. As the grain becomes hard
they carry large stores of it into their burrows to be eaten at leis-
ure, probably when they wake from their winter's sleep. The
amount of damage done depends upon the abundance of the ani-
mals and is often serious. If a field is small and isolated the sper-
mophiles sometimes collect and destroy almost the whole crop."
The above statement agrees in almost every particular with
reports of farmers in practically all parts of the state, so that
this animal is to be considered a menace to agriculture.

STRIPED SPERMOPHILE 33

These spermophiles do not go their way unmolested, for a num-
ber of natural enemies harass and kill them, thus holding the
numbers somewhat in check. Among the natural enemies of
spermophiles in the state may be mentioned the marsh hawk,
Cooper's hawk, red-tailed hawk and its subspecies, Swainson's
hawk and red-shouldered hawk; of the owls, the barn owl and
the great horned owl render valuable assistance in keeping down
the numbers of this destructive rodent. Among the mammals
which also render efficient service along this line may be men-
tioned foxes, skunks, and the badgers, which, however, are com-
paratively rare in the state. In Dubuque county it is reported
that skunks do much towards keeping in check the numbers of
striped spermophiles and no doubt this holds true for other local-
ities in the state. Of the weasels the long-tailed species (Putorius
longicauda] is of value in controlling the increase among sper-
mophiles for it enters the burrows and kills the occupants without
any difficulty. Some of the larger snakes such as the hog-
nosed snake and bull snake also destroy great numbers of spermo-
philes, particularly the young.

So, even without the aid of man, Nature makes certain provisions
for keeping the numbers of these animals within reasonable limits
and for preventing a too rapid increase. Thus is obtained a ' ' bal-
ance" in nature which Hudson Maxim has expressed as follows:
"The harmony of nature depends upon inharmony between the
meat-eaters (Carnivora) and the vegetable-eaters (Herbivora).
Their interests are, from their very nature antagonistic."

In spite of the efforts on the part of Nature to keep matters
adjusted, man has interfered and disarranged the plan by de-
stroying many of his friends which are the enemies of spermo-
philes. As a direct result of this the number of these animals
has increased very markedly in many localities with a resulting
increase in the amount of damage. On this account the expedient
of offering a bounty has been tried in some counties, in few of
which it has been continued for any length of time. The bounty
situation is taken up more fully under the discussion on the pocket
gopher farther on in this bulletin and so will be but briefly con-
sidered here. A bounty, at best, can be but a temporary method
of reducing the numbers of these or any animals and is altogether
impracticable as a method of exterminating them.
3

34 RODENTS OF IOWA

In Iowa, wherever bounty has been paid on these animals, it has
been at the option of the boards of supervisors and there has
been no uniformity in the matter of the amounts offered or in
the evidence required for payment of bounty. As a result, fraudu-
lent means have been employed in some instances to secure bounty
money and a considerable amount of the county funds has often
been diverted for such payment without securing adequate returns
for the amount expended. Not one of the counties visited during
the prosecution of this work pays a bounty upon the striped sper-
mophile, although some counties have paid in past years. As illus-
trating the point under discussion we may take Lyon county as a
typical example. In 1914, $2132.66 was paid out for all bounties.
During the two months March and April of that year, $1684.00 of
the above amount was paid out in bounty on the striped spermo-
phile and Franklin's spermophile at five and ten cents each re-
spectively. According to the county auditor the bounty on both
these animals has been discontinued, because it caused too great
a drain upon the county funds in proportion to the amount of
benefit derived.

While spermophiles do render some assistance to the farmer,
as has been indicated above, ways and means must be devised for
•combating them when the numbers become .excessive and crops are
damaged to a serious extent. However, a wholesale destruction
of the animals is not advisable and if serious damage is not done
they should be spared for the good which they do. In many lo-
calities this damage is very great and would be still greater if
some methods of control were not employed. In many places
which have been visited various control measures have been used
to which the bounty offered upon the animals is supplementary.
Among the effective and economical means for destroying these
animals may be mentioned fire arms, traps, poisoning, and fumi-
gation.

Under .certain conditions where the animals are not too numer-
ous or wary, small areas such as meadows and pastures may be
freed from spermophiles by shooting; but they soon become so
shy that it is difficult to secure them in this way and more eco-
nomical and efficient methods must -be substituted.

Trapping is slow but has the advantage in being sure, simple
and safe and spermophiles are easily taken in this way. For or-
dinary purposes the No. 0 steel trap with the spring under the pan

STRIPED SPERMOPHILE 35

has been found very effective. The trap should be chained to a
stake or heavy object and set at the mouth of a burrow; it should
be covered lightly with fine earth, and may be baited with almost
any kind of grain although the bait is not essential. The guillotine
traps of which there are many kinds on the market are also well
suited to this purpose since they kill instantly. Rolled oats or
almost any kind of grain may be used as bait.

For poisoning, the formula given under the discussion on the
prairie dog (p. 42) is very effective against spermophiles. A
teaspoonful of the poisoned oats should be placed near each
spermophile hole on the hard ground, letting it scatter somewhat
as it falls. Early spring, as soon as the animals are out of hiber-
nation and when the vegetation is not far along is the best time
to poison the animals.

Another poison formula which has been successfully employed
in the West may be added here :

Whole corn 16 quarts

Strychnin (alkaloid powdered) 1 ounce

Saccharin 1 teaspoonful

Flour % pint

Salt ' 1 pint

Water 1 quart

Dissolve the saccharin and, strychnin in the amount of water
called for, add the flour and salt, mix thoroughly with an egg-
beater and heat until the flour begins .to thicken, stirring con-
stantly Pour the poison solution over the grain and mix thor-
oughly, then spread and dry.

Follow the above directions closely, for success in the use of
the formula depends upon accuracy in the preparation of the
poison solution and upon the complete coating of the grain. A
half dozen kernels will suffice for each burrow and experiments
have shown that not more than one or two kernels are required
to kill an animaj.

Caution. — Do not put the poisoned grain where stock, birds, or
children will have access to it.

Fumigation by means of carbon bisulphid is also an effective
and cheap method of combating these animals. Carbon bisulphid
is a colorless liquid with a peculiarly offensive odor and is a
violent poison when taken internally. Its use in fumigation de-
pends upon the fact that it evaporates rapidly, giving off a poi-
sonous vapor which is heavier than air. For this purpose the

36 RODENTS OF IOWA

commercial variety is as good as and cheaper than the pure. To
use, roll into a ball about the size of a hen's egg a wad of cotton
or waste and saturate thoroughly with the liquid. Push this sat-
urated waste as far down the burrow as possible and quickly
•close the opening with earth to prevent any possible escape of
the fumes. The best time for fumigating is just following a rain
when the soil is saturated with water and the fumes of the liquid
are less likely to escape. With this method the animal is killed
within its own burrow and thus creates no offensive odor upon
decaying; while too, there is no risk of its poisoning any other
animal even though it be dug up.

Caution. — Carbon bisulphid is an inflammable and highly
explosive liquid and should not be handled near a fire or near
anyone who is smoking. It also evaporates very rapidly and
should be kept tightly corked.

FRANKLIN'S SPERMOPHILE. GRAY GROUND SQUIRREL.
GRAY GOPHER. GRAY PRAIRIE SQUIRREL.

Citellus frariklini (Sabine).
Arctomys franklinii Sabine, Trans. Linn. Soc. XIII, 587, 1822.

Description. — Color above, except on head and tail, yellowish
or grayish brown, the hairs marked with blackish; top and sides
of head and neck blackish lightly speckled with white; a buffy
ring around the eye; color below buffy white; tail grayish with
three blackish lines, the outermost broad and fringed with white.

In the young the brownish or tawny tinge is not so evident
and the back has irregular blackish bars.

Measurements. — Total length, 14.75 inches; tail vertebrae, 4,75
inches; hind foot, 1.85 inches.

This form resembles somewhat a small gray squirrel, but may
at once be known by the shorter and less bushv tail, the more
evident tawny tinge of the upper parts, and the very short ears.

While this animal possesses a very great number of popular
names, none are employed consistently throughout its range ex-
cept perhaps the least known of these, Franklin's spermophile —
the only one which is properly applicable to this form and the one
which we shall employ in this discussion.

Habits, Distribution, Etc. — Franklin's spermophile is an inhab-
itant of open prairies and is not found in timbered regions, al-

FRANKLINS SPERMOPHILE 37

though it often lives along the edges of timber and small groves.
At Lake Okoboji it is quite common near the sparse woods and
groves bordering the water, and has even taken up its abode near
the buildings of the Lakeside Laboratory. In most places it is
not as common as the striped spermophile although in a few local-
ities it is reported as more common than that species. In most
places, the two species range together and their habits are also
very similar. The note of Franklin's spermophile is the same
rapid, shrill trill of the striped spermophile but somewhat heavier.
As with the other spermophiles, this form is often seen sitting
erect and motionless on its hind feet near the opening to the bur-
row. When alarmed it usually runs with a low, sneaking gait
through the grass, but when very much frightened takes long leaps.

This species also constructs a burrow which is similar to that
of the striped spermophile but somewhat deeper; in many cases
these burrows are excavated in cultivated fields. The nests to
which the burrows lead are constructed of grass and soft plants
and are always kept clean and sanitary. In autumn Franklin's
spermophiles become very fat and disappear within their bur-
rows not to reappear until the following spring. The time of
reappearance varies with the season, but is usually during the
first half of April. The young are produced during the latter
part of May and by the first of August are half grown.

This species is more migratory in its habits than the striped
spermophile ; the males live a wandering life during the summer,
and indeed pairs or even small companies of individuals fre-
quently migrate from one locality to another; sometimes a pair
will migrate from the wintering burrow to a breeding burrow
and perhaps winter in still another. This migratory habit may
account for the reports received from various places to the effect
that "this species was common here last summer, but I have seen
only a very few this year. ' '

From various sources it has been learned that not often do this
species and the striped spermophiles inhabit the same field; and
it seems that the latter, being somewhat more pugnacious, drive
the Franklin's spermophiles from any limited territory which
they themselves wish to occupy.

Although this form is quite generally distributed throughout
the state, in the driftless region of northeastern Iowa it is not
commonly met with. It seems, however, to be working its way

38 RODENTS OF IOWA

into this region from the north and west, and a few miles west of
the hilly section it is fairly? common. At Corning it is reported
that this species did nol appear until 1909; now it is abundant
in that locality. In almost every locality visited Franklin's sper-
mophile is found ; but its numbers are, in general, less than those
of the striped spermophile. Definite locality records are: "West
Liberty, Iowa City, Ruthven, Gilmore* Des Moines, Mt. Pleasant,
Algona, Hampton, Carroll, Muscatine, Osceola, Corning, Eldora,
Rockwell City, Lake Okoboji, Rock Rapids, Spencer, and Cherokee.

Food Habits, Economic Importance, Etc. — Most of the food of
Franklin's spermophile consists of seeds and various cultivated
grains. Corn, wheat, oats, rye, and barley are among its favorite
foods; and much complaint is heard from farmers in many sec-
tions of the state as to the damage done by this spermophile 's
digging up newly planted grain. Corn, in particular, is attacked
in this way, and when the animals are numerous replanting and
careful watching are necessary in order to secure a crop. On one
farm in Henry county it was found necessary to replant more
than forty acres of corn during one season on account of ravages
by these animals. Of course the amount of damage done in a
locality is in direct proportion to their numbers, and where they
are numerous damage may be quite serious. Among the ripe
small grains more of the grain is trampled down in attempting
to get at the heads than is actually eaten, so that considerable
loss occurs in this manner also.

"While grains and other vegetable food make up a large share
of the entire food of Franklin's spermophile, animal food is also
taken. Many insects such as beetles, crickets, grasshoppers, cater-
pillars, and ants also are eaten and thus perhaps some of the evil
which it does is mitigated by its usefulness in destroying these
noxious forms.

On the farms damage is also sustained from the animal owing
to its inclination to burrow in or along the banks of ditches and
under drains filled with brush so that when heavy rains come
these banks are more easily washed away.

Natural enemies of various kinds, among them the hawks and
owls mentioned as enemies of the striped spermophile, tend to
keep down to a certain extent the numbers of Franklin's sper-
mophile. A good many 'are caught by house cats also in regions
where these spermophiles are abundant, since they seem to have

FRANKLIN'S SPERMOPHILE 39

a habit 'of frequenting old buildings and even situations near
buildings which are in use; this coupled with the fact that they
are perhaps somewhat less active than the striped spermophiles
renders them more liable to attack by the felines.

Franklin's spermophiles have long been recognized as enemies
of agricultural interests and the expedient of offering bounty
has been resorted to in various counties in the, hope of either ex-
terminating them or materially reducing their numbers. These
sporadic attempts have not met with any degree of success. Al-
though it is apparent that this species is recognized as more de-
structive in its habits than the striped spermophile, the added in-
centive to its capture in the way of a larger bounty offered has
proved of no avail. . In none of the 'counties visited is a bounty
now paid upon these animals ; but in several, bounties once in vogue
have been discontinued because they did not bring the desired
results. In some places inquiries are made by farmers from time
to time as to whether a bounty is paid. Certain localities seem
still to indicate a sentiment towards paying a bounty but indicate
further that it should be uniform throughout the state. The
bounty system is considered more fully in the discussion on the
pocket gopher.

In general, the same .control measures recommended for the
striped spermophile are applicable to the Franklin's spermophile
when its numbers become excessive in any locality. In addition,
these animals as well as the striped spermophiles, may be drowned
out by pouring water into their burrows and since this species is
less active than the striped spermophile it may be more easily
killed with a club when it leaves the burrow following such a deluge.

In Clay county much success in 'controlling the numbers of
Franklin's spermophile has been met with in the use of poisoned
corn. A solution of strychnin sulphate, two ounces to two quarts
of water, is made, and shelled corn is soaked over night in this.
The poisoned corn is then scattered along the edges of fields and
in fields infested with this spermophile. While this method has
been found effective, it is not especially recommended since the
poisoned grain may be eaten by birds and other animals for
which it is not intended. Instead of scattering the corn promis-
cuously it is better to put a few! grains at the entrances of the
burrows as this lessens the likelihood of other animals feeding
upon it. Care should be taken that domestic animals are kept
from the poisoned grain.

40 RODENTS OF IOWA

BLACK-TAILED PRAIRIE-DOG. PRAIRIE-DOG.

Cynomys ludovicianus ludovicianus (Ord).

Arctomys ludoviciana Ord, Guthrie's Geogr., 2d Amer. ed., II,
292, 302, 1815.

Description.^Summer: Above reddish brown, varied with
gray and black hairs; upper lip, sides of nose and eye ring buffy
white; cheeks and sides of head buffy with blackish hairs; feet
buffy; tail above like back, the apical third black or blackish
brown above and below; under parts of body from chin to near
tail white or buffy white. Winter: Pelage much thicker, longer
and softer than in summer; above, grayish cinnamon with numer-
ous intermingled black hairs; tail as in summer; under parts
pale buff or cinnamon, the hairs black at bases.

Measurements. — Total length, 15.57 inches; tail vertebras, 3.50
inches; hind foot, 2.57 inches.

Owing to the fact that both summer and winter coats fade and
wear, the variations in color are very great. All prairie-dogs
but one species have two molts annually; these molts are entire
except on the tail where there is but a single yearly renewal; as
a result, specimens may be found in all stages of intergradation
depending somewhat upon the season.

The prairie-dog is one of the true ground squirrels or spermo-
philes and the appellation "dog" is not strictly in accordance
with science. However, owing to the very general usage of the
word in connection with this animal a substitute would perhaps
be out of place.

Habits, Distribution, Etc. — Although the prairie-dog appears
to have made but little headway in increasing its range in Iowa,
and although it is present in only a few restricted localities along
our western border, it will bear watching and any further spread
of the species should at once be combated. Sometimes it is prac-
tically omnivorous, feeding upon grasses, roots, stems, and leaves
of green plants. Without doubt it is responsible, in western local-
ities, for great damage to grain and pastures; and in some places
practically the entire forage crop would be lost unless preventive
measures were taken. Of course in many localities the "towns"
occupy waste places and in such instances they do not interfere
with man. In their natural habitat, the Great Plains and Rocky
Mountain regions of the United States, these animals are gre-

42 RODENTS OF IOWA

garious, and some of the villages extend for miles while the num-
ber of inhabitants is very great.

The burrows in which the animals live vary according to local
conditions. In arid regions the mounds are usually small ; but in
places where the rainfall is great, high mounds are necessary and
require the constant care and attention of the animals. Prairie-
dogs, except at high altitudes, do not hibernate, although they may
remain under cover for days during severe winter weather. They
may, however, appear above ground on fine days even though
the ground is covered with snow. In the extreme north, when
deep snow 'covers the villages for many weeks the animals remain
concealed for long periods.

Prairie-dogs are attacked by a number of natural enemies among
which are the coyote, badger, eagle, black-footed ferret, and rough-
legged hawk. Although many stories) have been told concerning
the occupancy of a single burrow by prairie-dogs, burrowing owls
and rattlesnakes, careful observation shows that while all these
animals are often found together, the association is not of ad-
vantage to the prairie-dog, for many of its young are sacrificed
to the intruders.

Control Measures. — In many localities where the animals are
abundant various measures of extermination have been tried,
among the best of which is the use of poison-coated grain. A for-
mula similar to the one given below has been employed with ex-
cellent results in North Dakota and elsewhere and is equally ef-
fective in destroying Franklin's and the thirteen-lined spermo-
philes.

Formula for poison preparation:

1. • Mix thoroughly 1 ounce strychnia sulphate (powdered) and

1 ounce baking soda.

2. Sift this into % pint thin hot starch paste and stir to a

creamy mass. Make the starch paste by dissolving a table-
spoonful of dry gloss starch in a little cold water, then add
this to % pint of boiling water. Boil and stir constantly
until a thin paste is formed.

3. Add % pint heavy corn syrup and stir thoroughly.

4. Add % ounce saccharin (or sugar 1 pint) and stir thor-

oughly.

5. Pour poison solution over 15 quarts clean oats and mix thor-

oughly so that each grain is coated. Prepare 24 to 48
hours before using.

34

44 RODENTS OF IOWA

6. Distribute a tablespoonful of poisoned oats on the clean, hard
ground before the hole. A quart of grain will be sufficient
to treat forty holes. Put out in early morning and take
special care that the grain is not put on the loose earth
of the mound or into the burrows. Do not put out in rainy
weather, and take special precautions that other animals,
particularly birds, do not reach it. Poisoning is best done
in early spring before the vegetation is well along.

The Prairie-dog in I&wu. — The prairie-dog has been reported
from a number of localities in Iowa, but in most cases the records
are for introduced individuals or colonies. Introduced colonies
are reported to have existed at Burlington, and from Jackson
township in Sac county a prairie-dog town of about twenty bur-
rows was reported in 1900 ; but in both cases it is likely that the
individuals were escaped pets or their descendants. A specimen
reported to have been killed in Palo Alto county a few years ago,
was probably an escaped pet since such an animal had been lost
some time before the specimen mentioned was killed. At Logan
in Harrison county a specimen of this species was killed in a
lumber yard in 1916, but it appears likely that this also was an
introduced individual. M. P. Somes reports that he has seen
"two small colonies of the prairie-dog between the Missouri River
and the C. M. & St. P. R. R. tracks about five miles north of
Calliope in Sioux County." Frank C. Pellett says, "Knew of
one in Cass county several years ago."3

At the present time J. A. Moody of Shenandoah has two small
colonies of prairie-dogs on his farm, one colony about one hundred
and fifty yards from his home, the other about forty rods dis-
tant. He writes as follows regarding the animals: "They were
not native of this part but a single pair was sent me some 20
years back from Fort Morgan, Colorado. The animals increased
rapidly as each mother dog will rear an average of about
six young each year. They are inclined to be very domestic and
will not wander away from their little towns unless overcrowded.
In that case they will seek other parts. . . .Nothing is allowed to
grow within the bounds of their colony but grass ; not a weed or a
bush is allowed to grow. This is for their own protection. The
colony nearest our home contains about thirty, the larger one about
a hundred .... If not allowed to become too numerous and colonize
on pasture land they will remain there and will not molest the near-
by growing crops in any way. For destroying the animals I use

3Proc. la. Acad. Sci., XVII, 214, 1910.

THE WOODCHUCK 45

carbon disulphide .... The holes run down at an angle of about 45
degrees to a depth of nearly or quite seven feet, then they con-
tinue their burrows for some four feet further on a level. At the
end a spacious room is rounded out large enough for the family
that is to occupy the snug, warm place."

The above records seem to indicate that the prairie-dog is not
particularly successful in maintaining itself in the state, even if
it is introduced ; and the Missouri river seems to have served as a
fairly effective natural barrier to its eastward dispersal from Ne-
braska. It may, however, be in place here to utter a timely word
of warning in regard to the introduction of such noxious animals
as pets or for exhibition. As has been pointed out before this is a
species which may become a pest and a menace to agriculture on
account of its fecundity, its adaptability, and its food habits; so it
were better not to take any chances of its spreading by introducing
it into any locality. If specimens are brought into the state great
care should be taken that they be placed in properly constructed
cages from which there is no possibility of escape. Such a serious
matter should receive due forethought and consideration and care
should be exercised that this pest of western states does not obtain
a foothold in our own.

SOUTHERN WOODCHUCK. WOODCHUCK. GROUNDHOG.

Marmot a monax monax (Linnaeus).
[Mus] monax Linnaeus, Syst. Nat., X ed. I, 60, 1758.

Description. — Color above grayish brown, the hairs of the back
reddish brown with gray tips and black bases; cheeks gray, the
mouth margined with whitish ; nose and chin gray ; tail dark brown,
the hairs tipped with gray; color below brownish chestnut; feet
brownish or blackish; throat grayish.

Measurements. — Total length, 23.25 inches; tail vertebrae, 5.50
inches ; hind foot, 3.50' inches.

This species is somewhat variable both as to size and coloration ;
in length it varies from twenty to twenty-five inches, and in colora-
tion from pure white to black; although, of course, specimens col-
ored some shade of gray are much more common than are specimens
of other colors.

Habits, Distribution, Etc. — The woodchuck is a common rodent
throughout the eastern half of the state, but is seldom met with in
the extreme western counties. It is the largest common rodent

46 RODENTS OP IOWA

now existing in the state and in point of size is exceeded only by
the porcupine and the beaver, neither of which now probably occurs
within our borders. Frank C. Pellett has a specimen taken at
Atlantic in 1916, and says that he has seen but one other in Cass
county during- the last thirty years although he has heard of two
more specimens) that have been taken in that county. In North
American F&una No. 37, 1915, a specimen of this form is recorded
from Wall Lake. At Emmetsburg a specimen was taken; a few
years ago along the west branch of the Des Moines river. Along
the Chicago, Milwaukee & St. Paul Railroad tracks between Fos-
toria and Milford the writer found two burrows of this species.
The above data indicate that while the woodchuck is found occa*
sionally in the western part of the state its numbers there are much
less than in our eastern more wooded and rougher counties.

The woodchuck, or ground hog as it is commonly called, is fre-
quently found in open prairie fields, where it digs burrows in the
ground. In hilly regions it often constructs its burrows in the side
of a ledge of earth or fill. The animal is seldom found in wooded
areas, but often digs its burrows along the edges of woods or groves.
The burrows vary considerably in length and form. The shorter
burrows are in most cases not more than ten feet in length, while
few of the longest are longer than fifty feet; usually they extend
parallel to the surface of the earth and four or five feet below it,
and each burrow ordinarily has at least two points of entrance.

The following sketch shows the plan of a woodchuck burrow
examined by Charles B. Cory at Lake Geneva, "Wisconsin, and is
taken from his book, "The Mammals of Illinois and Wisconsin,"
page 153.4 Usually only a single pair of the animals inhabits a
burrow. The young are produced in the latter part of April, and
there are usually from four to six in a litter. They are very small
and blind when born and do not emerge from the burrow until
permanent warm weather occurs.

Woodchucks do not store up food for winter use, for they hiber-
nate during the cold season. A popular superstition is abroad
to the effect that the woodchuck emerges from its burrow on the
second day of February and looks about. If he sees his shadow
cold weather, it is thought, will continue for a period of at least
six weeks and he will return into his burrow to continue his sleep
for that length of time; if, however, he fails to see his shadow,

4Cory, Charles B., Pub. Field Mus. Nat. Hist. Zool. Series, Vol. XI, 1912.

THE WOODCHUCK 47

spring will open early and the cold weather will be of short dura-
tion. Of course there is no truth attached to this superstition and
the way in which it arose is merely a matter of conjecture.

Pile*,

_____ Pile of Je

Entrance
on slope of hill

4/16 in, deep.

FIG. 9. — Plan of a Wloodchuck burrow. (From Field Museum of Natural

History.)

The wood-chuck is more particularly a ground inhabiting species
and does not habitually climb trees. It is able, nevertheless, to
climb with a fair degree of skill. "While walking along the road
near Waukon, in northeastern Iowa, the writer once disturbed an
adult of this species which had been feeding on the vegetation in
a nearby pasture. The animal galloped rapidly through the grass
to a small white oak tree a few yards distant and ran up the trunk
about ten feet without apparent exertion. The animal was soon
dispatched with a club, and on opening the stomach it was found to
be entirely filled with blades of green grass and the leaves and
stems of weeds.

Food Habits, Economic Importance and Control Measures. —
Woodehucks are, for the most part, vegetarians in their food habits,
the favorite food being grasses and clover; but if present in locali-
ties where truck crops are raised, they will eat pumpkins, beans,
cabbage, melons, young corn, etc. They are very fond of corn
when it is in the milk, and often destroy much more than they eat
by breaking down the stalks and leaving the ears half-devoured.
The animals feed regularly morning and evening and often during

48 RODENTS OF IOWA

the day and on clear, moonlight nights. Usually they are quite
shy and when disturbed move with a low, loping gait. If .cornered
they are able to put up a very presentable fight.

In many localities farmers report this species as destroying young
chickens and ducks. One of the members of the board of super-
visors in Dallas county in 1914 reported to the writer several such
instances, and further said that in a single night sixty of his young
chickens which were kept in a brooder were killed and some were
partly eaten by these animals.

In Dubuque, Dallas, Clarke, and other counties visited, these
animals .cause considerable damage by making burrows behind the
abutment walls of small bridges; and in many instances entire
approaches to bridges have been washed out during heavy rains,
en account of their having been undermined by woodchucks. The
animals seem to be most troublesome and abundant on low roads
near timber; on the higher roads away from the timber their
harmfulness is not so great. Of course cement bridges and cul-
verts offer something in the way of protection in such cases, but
even with such precautions considerable damage often follows.

In places it is reported that these animals burrow under shocks
of grain, not only destroying the grain but in addition leaving
large holes in the earth which may be the beginnings of washouts
or in which farm stock may step with possible serious injury.

Again, many complaints have teen made that the "dead earth"
thrown out by the animals in constructing their burrows covers
up the vegetation and underlying productive soil, and that the
earth thus thrown out is not productive until it has been fertilized
and cultivated for a time.

The flesh of the woodchuck is said to be very palatable and
there is no good reason why it should not be considered fit for
food. The habits of the animals are cleanly, the burrows and
nests are clean, and there is nothing in their food habits to render
them objectionable. The fur is not much used, since it is harsh and
coarse ; but the skin when tanned makes a good, pliable, and wear-
resisting leather. .;

In consideration of its damage to agricultural interests and to
the successful upkeep of good roads, which have now come to be
a necessity, the woodchuck must be reckoned with; and here as
in other instances attempts have been made in some counties to
reduce the numbers by offering bounties. The following table

THE WOODCHUCK

49

will show in condensed form the bounty situation in the counties
in which inquiry has been made.

RATE AM'T PAID ON

COUNTY (CENTS) DATE WOODCHUCKS
Allamakee 10 1914 (June) $112.10

250.00

1915

Buchanan

25

1913

1915

Clay

25

1913

1915

Clayton

25

1913

1915

Dallas

15

1913

1915

Davis

25

1913

1915

Delaware

20

1913

1915

Fayette

20

1910

1915

Henry

20

1913

1915

Union

15

1913

1915

Wapello

25

1913

1915

Winneshiek

10

1913

1915

2.50
8.35

1,314.00

1,665.15

53.60

1.50

146.75

714.20

763.45

2,064.80

22.95

6.50

10.50
2,786.00

REMARKS

1909 offered 15c each; 1912 $1.00

a dozen
Discontinued

Discontinued

Began paying bounty in 1911

Discontinued

Paid only in 1910 and 1911

Withdrew in 1912

No bounty

Bounty in 1913 and 1914 only

No bounty

Total bounty on gophers, wolves,
foxes and woodchucks

Of the sixty-two counties visited during the preparation of this
paper but five are now paying a bounty on this animal, although
some others have paid a bounty in times past. The most common
answer to the question as to why the bounty on woodchucks was
discontinued is that it has been too great a drain upon the county
funds in proportion to the results obtained. In looking over the
table it will be seen that no uniformity of bounty prevails, and
that the rate differs from ten cents to twenty-five cents. In some
cases the rates in adjacent counties present a considerable differ-
ence and animals killed in the county offering a small bounty
are often taken to the county in which a larger bounty is paid.
It would seem that the bounty in order to be at all effective and
fair to everyone concerned should be uniform in all parts of the
state. However, the bounty system is not here advocated as an
effective method of dealing with the woodchuek situation. In lo-
calities where the animals are plentiful and a cause of consider-
able damage, trapping may be resorted to with excellent results.
"Woodchucks are easily caught in steel traps and if every farmer
4

50 RODENTS OF IOWA

whose land is infested with these animals would see to it that the
numbers are reduced and held in check the situation could be much
improved without the expenditure of county funds. The animals
can also be shot without difficulty, the principal prerequisite on
the part of the hunter being a fair degree of ' ' watchful waiting. ' '

BEAVERS.

Family CASTOR1ME.

This family is made up of but a single genus, represented in
North America by one species, of which there are five recognized
geographical races.

Beavers are the largest of the North American rodents, varying
from thirty to fifty pounds in weight, and excepting the capybara
of South America, are the largest of existing rodents. The ani-
mals are semi-aquatic and the arms and hands are small and adapted
for burrowing as well as for holding substances between them.
Beavers were and still are in localities where they are sufficiently
plentiful, hunted and trapped for their skins which are of great
commercial value. In addition, the anal glands of the animal con-
tain an oily, yellowish, sticky, and strongly-scented fluid called
castoreum which is used by trappers as a bait ; it is also used in the
manufacture of perfumes, and is furthermore asserted to have
medicinal properties.

The beaver, as a type, is one of the oldest living mammals, and
has been contemporaneous with many now extinct species. His
prolificacy, semi-aquatic, habits, rugged strength, and food habits
have fitted him for successful maintenance in his struggle for exist-
ence. However, the competition with avaricious man has been too
great, and in many places where he was formerly abundant the
beaver is now entirely extinct. In both the United States and Can-
ada governmental protection has in recent years, been given this
animal, and its numbers are now somewhat on the increase.

BEAVER. CANADIAN BEAVER.

Castor canadensis canadensis Kuhl.
Castor canadensis Kuhl, Beitr. z. Zool., 64, 1820.

Description. — General color brown; hairs of upper part dark
brown at base and tipped with chestnut ; top and sides of head and
neck, rump and thighs chestnut; under parts paler than upper

CANADIAN BEAVER 51

parts; tail flat, scaled, paddle-shaped, black in color; claw on sec-
ond toe of hind foot divided.

The fine or true fur varies in length from one-half to three-fourths
inch while the coarse bristle-like hairs are from; one and three-
fourths to two and one-half inches in length, and are dense enough
to entirely or almost entirely conceal the fur proper.

Measurements. — Total length, 42.00 inches; tail vertebrae, 16.25
inches ; hind foot, 6.75 inches. The bare scaly portion of the tail is
about 9.00 inches long, by 4.50 inches wide, and 1.50 inches through
the thickest part.

The beaver is somewhat variable as to both size and coloration,
reddish brown, however, being the prevailing color; adults weigh
from thirty to sixty pounds though the latter weight is attained
only in rare instances.

FIG. 10'. — Pet Beavers. (From U. S. Department of Agriculture.)

Although in early days beavers were very common in almost all
parts of the state, they have been entirely exterminated, the last
individuals apparently having been killed in the early nineties.
John A. Spurrell of Wall Lake, informs the writer that the last
beavers trapped on the Boyer river in Sac county were taken in
1886. M. P. Somes reports that a beaver was killed on Lizard creek,
about five miles northwest of Fort Dodge by J. T. Somes about 1887.
"A family of beavers is reported by Sirrine as having worked on

52 RODENTS OP IOWA

Big Creek, North Tama county, for eight years past, but not a
trace of them could be found last fall/'5

Doubtless many other records of the occurrence of this rodent
in different parts of the state could be collected ; but they would
serve no useful purpose so far as the object of this paper is con-
cerned, and those above given will suffice.

BATS AND MICE.

Family MURID/E.

The Muridaa is the largest family of rodents and, indeed, of the
whole class of mammals, as it numbers over five hundred forms.
The family is cosmopolitan in distribution, and some forms such
as the brown rat are met with throughout the world, having been
carried from place to place in shipping. Every country, including
North America, has its own peculiar species. Both terrestrial
and aquatic forms are found in the family. Various localities and
habitats are chosen according to the mode of life ; and swamps,
lakes, rivers, prairies, cultivated lands, and woods all have their
representatives. In size the members of the family vary from the
small harvest mice to the muskrat, the largest representative of
the family.

HOUSE MOUSE.
Mils musculus Linnaeus.
[Mus] musculus Linnaeus, Syst. Nat., X ed.. I. 62, 1758,

Description. — Color above dark brown grading to lighter brown
on sides of body; color below grayish brown, but without distinct
line of demarcation between color of this part and that of sides;
tail dusky, scantily haired and longer than body ; feet grayish
brown.

Measurements. — Total length, 6.75 inches; tail vertebra?, 3.15
inches ; hind foot, .75 inch.

This form may be distinguished from our other small mice by
the grayish brown under parts, the size, the length of tail, and the
fact that the molars or grinding teeth have the tubercles on the
crowns arranged in three longitudinal rows.

Habits, Distribution, Etc. — The house mouse is a species intro-
duced into this country from Europe, arriving soon after the first
American settlements were established. It now inhabits all the

'Nutting, C. C., Proc. la. Acad. Sci., I, pt. Ill, 40, 1892.

THE HOUSE MOUSE

settled parts of North and South America and occasionally is found
even in unsettled districts. It usually reaches a new settlement
sooner than the rat, but on account of its small size it does not do
so much damage as that species. However, its presence is just as
objectionable, and it has the advantage over its larger relatives in
being able to crawl through very small holes.

FIG. 11. — Northern White-footed Mouse (left). House Mouse (center). Prairie
White-footed Mouse (right). Photo from life by Frank C. Pellett.

The house mouse is extremely prolific, several litters of from four
to nine each being born in a year. The usual number in a litter is
five or six and the young reach maturity in about three months.

The nests are usually constructed in buildings or cellars and
are made from various materials that have been chewed into bits.
Paper, clothing, and articles of leather in many cases form the
basis cf these nests. Often, too, the animals nest out of doors in
gardens and fields, and numerous specimens caught in such places
have been sent in to the writer from time to time.

House mice are practically omnivorous in their diet; they feed
upon all kinds of animal and vegetable matter, and pollute much
that is not eaten. Serious fires are caused when the animals gnaw
matches, and floors, furniture, clothing, books, and other stored
articles are damaged by their teeth. In addition, these mice are
important carriers of bubonic plague and other diseases of human

54 RODENTS OP IOWA

beings. During the summer months serious losses to grain in the
shock and stack are sustained by their depredations.

When present in any numbers this mouse destroys considerable
amounts of food and stores, yet all efforts to exterminate it in the
United States have proved futile. Indeed its numbers seem in no
way to be diminished.

Various control measures have been employed in keeping down
the numbers of house mice, such methods being1 applicable, in gen-
eral, for the house rat. The details of these measures are discussed
in connection with the latter animal. Suffice it to say here that
precautionary and concerted action will do more toward* the lessen-
ing of damage than is generally believed and such measures should
receive widespread support.

HOUSE RAT. BROWN RAT. NORWAY RAT.

Rattus norvegicus (Erxleben).
[Mus] wyrvegicus Erxleben, Syst. Regni Anim., I, 381, 1777.

Description. — General color above grayish brown, darkest on
middle of back, the over hairs of the upper parts tipped with black ;
sides grayer; color below pale grayish brown; hair coarse; tail not
longer than head and body, usually less; tail scaly and sparsely
haired, above dusky, beneath paler.

FIG. 12. — The Brown Rat. (From U. S'. Department of Agriculture, Bureau of

Biological Survey.)

Measurements. — Total length, 16.50 inches; tail vertebrae, 7.10
inches; hind foot, 1.75 inches.

THE BROWN RAT 55,

Eats must be classed as one of the most successful of all groups
of animals, and this success is due, in large measure, to their abil-
ity to adapt themselves readily to their surroundings. Not only do
they exist under seemingly adverse conditions, but they breed and
multiply.

This is the common rat found about barns and houses in the coun-
try and about warehouses, markets, and wharves in cities. It is
supposed to be of Asiatic origin, but its status in this respect has
not been definitely determined. It is known that the species
reached England from the east, about 1729, having probably mi-
grated thence from northern Asia, and it was first reported in Paris
in 1750. It was introduced into the United States, probably from
England, about 1775, where, in spite of many attempts at 'control
and extermination, it has increased in distribution as well as in
numbers. J. A. Spurrell of Wall Lake, Sac county, writes as fol-
lows in regard to the first occurrence of this species in that county :
' ' The first gray or barn rat came from New York in the spring of
1858 in a box of goods. It escaped and was trapped the following
fall. Barn rats were next reported in 1868."

Since the brown rat is usually transported in ships, it often be-
comes first established in a new locality at seacoast towns and from
thence works its way inland. Audubon and Bachman report the
brown rat as not having reached the Pacific Coast in 1851, but Baird,
in 1857 says, "At the present time, however, it is very abundant
there [on the Pacific Coast] as far north as the Columbia River."6
Other writers have thought that this rat appeared in certain Cali-
fornia cities even before 1851. At any rate, within a period of ap-
proximately eighty years, this pest became pretty generally dis-
tributed over almost the entire United States.

Habits, Distribution, Etc. — The brown rat is one of the most
abundant rodents in the state. It usually breeds more rapidly than
it is destroyed ; and such places as stables, warehouses, creameries,
sewers, and markets where its food is abundant are often swarm-
ing with the pests. Refrigerating plants, cars, and ships also harbor
them ; and cases have been reported of vessels carrying refrigerat-
ing plants which had not been subject to fumigation for a long
time, in which the animals had grown an extraordinary coat of fur,
which served as a protection against the extreme cold.

«Pac. R. R. Reports, VI, General Report, 439, 1857.

56 RODENTS OF IOWA

Without doubt the rate of increase among rats is more rapid in
temperate climates, extremes of heat and cold retarding multipli-
cation by decreasing the number of litters and the number of young
in each litter. A plentiful supply of stored grain or other nutri-
tious food is also conducive to rapid multiplication and maturity.
While young may be found throughout the year, early spring and
summer are the periods of greatest reproductive activity. Briefly
summarized, the breeding habits of the brown rat as stated by
Lantz are as follows : ' ' The animals breed from three to five times
a year, each time bringing forth from 6 to 19 young. After a ges-
tation period of twenty-one days the females give birth to their
young in nests built in underground burrows or under floors, stacks,
lumber, wood piles, or other shelter. The young are blind and
naked when born, but grow rapidly, and young females are .capable
of breeding when less than three months old. ' '7 In central United
States observations show that this rat breeds from six to ten times
in a year and produces in each litter an average of ten young.

Inland, where living conditions 'change with the season, movement
of rats from houses, barns, and outbuildings to the fields occurs in
spring when the green vegetation lures them forth. Upon the ap-
proach of autumn they again seek the shelter of buildings and an
abundant food supply in the way of stored grains. While these
seasonal migrations are commonly observed, more general move-
ments sometimes occur in which great numbers of rats invade, in
a body, new territory, taking up their abode and causing heavy
damage. It is probable that these extensive movements are brought
about by overcrowding and the consequent reduction in the food
supply.

The brown rat is more pugnacious than the black rat, and in
places where the latter formerly held sway it has been driven out
by its more formidable relative. Rats seldom attack human beings,
except perhaps in self defense ; and contrary to a popular opinion
the bite is not poisonous, though it may be dangerous owing to the
likelihood of infection setting in.

The sight of rats is not keen in daytime, as is indicated by the
fact that they move about slowly and with hesitation. However,
the whiskers serve as feelers- and in them the sense of touch seems
to be particularly well developed. It is a common observation that

7Lantz. D. E., Nat. Hist, of the Rat, in "The Rat and its Relation to the
Public Health" : Treas. Dept., Pub. Health and Marine Hospital Service of
U. S., 1910.

THE BROWN RAT 57

rats in attempting- to escape an enemy will run along a wall or the
side of a room with much greater certainty than in the open.

Food Habits, Economic Importance, and Control Measures. —
Bats are practically omnivorous in diet, and it is in part due to this
fact that they are able to maintain themselves under seemingly ad-
verse circumstances. The following are some of the principal
articles of diet : grain and seeds of practically every variety with
the food products made from them ; fruits and garden crops ; bulbs,
roots, stems, leaves, and flowers of herbaceous plants ; bark of trees ,-
eggs, milk, and butter; young chickens, ducks, and other poultry;
fresh and decaying meat; mice, rats, fish, frogs, and mollusks.
Water is taken in considerable amounts.

The usual feeding time of rats is after sunset, especially if there
is more or less disturbance in the vicinity during the daytime. In
situations where they are not often disturbed they will feed in day-
light. Cellars of houses and the basements of granaries and cribs
are the places often chosen for homes ; and from the burrows which
they usually construct in these places the rats make excursions
through the buildings at night in search of food. If food becomes
extremely scarce the stronger animals sometimes kill and eat their
weaker brethren.

It is estimated that rats cause an annual loss of $200,000,000 in
the United States alone. Not only the amount of food actually
eaten but also that which is polluted and rendered unfit for use
must be taken into consideration ; so that the material losses thus
sustained form sufficient argument for the destruction of the pests.
The useful work that is done by rats as scavengers is very slight
when compared with their detrimental qualities, and there is ade-
quate reason for saying that the animals should be exterminated if
possible.

In addition to the food that is eaten and destroyed by rats and
mice considerable damage is done in other ways. Stores and ware-
houses are invaded and silks, carpets, furniture, furs, leather goods
and many other articles are damaged. More than one serious fire
can be attributed to rats, because of their gnawing matches or the
insulation of electric wires in buildings. Houses are in some cases
flooded because the animals have gnawed through lead pipes and
occasionally leaks in lead gas-pipes are to be accounted for from
the same source.

58 RODENTS OF IOWA

The foundations of floors and buildings are in some instances un-
dermined by rats, thus causing the structures to sag or to fall.
Unsightly holes in uncemented cellar floors and walls usually indi-
cate the presence of these pests. The corners of doors and of boxes
containing stored materials are eaten away; and even artificial
ponds and embankments may be ruined by the numerous burrows
of the animals.

Rats are also objectionable from an hygienic point of view and
are known or suspected to be the transmitters of several diseases.

It is believed that rats are responsible for the presence of human
plague in a community, and also that they frequently carry the dis-
ease from one locality to another. Bat leprosy is not an uncommon
disease among these animals and is of interest because of its similar-
ity to that disease in man. In March, 1917/T. T. Job of the
Department of Animal Biology of the State University came upon
a specimen bearing this disease. The rat was collected in one of
Iowa City's livery stables.

A number of species of internal parasites are harbored by rats
and mice, and some of these parasites bear a close relation to certain
diseases of man. The disease known as trichinosis,, due to the
presence in the body of minute parasitic worms called trichinae or
flesh-worms, is most frequently carried by rats and mice and prob-
ably will never be entirely eradicated from man until these rodents
themselves have been exterminated. For this reason rats that have
been killed or trapped should never be fed to swine, but the bodies
should be buried or burned.

Natural Enemies. — To the all too widespread desire for the kill-
ing off of birds and other animals which habitually prey on de-
structive rodents, rats and mice included, the great increase in the
number of such pests is largely due. ' * The value of carnivorous
mammals and the larger birds of prey in destroying rats and mice
should be more fully recognized, especially by the farmer and game
preserver. Rats actually destroy more poultry and game, both eggs
and young chicks, than all the birds and wild mammals combined ;
yet some of their enemies among our most useful birds of prey and
carnivorous mammals are persecuted almost to the point of ex-
tinction. An enlightened public sentiment should cause the repeal
of all bounties on these animals and afford protection to the ma-
jority of them. ' '8 Greater care should be exercised in discriminating

8Lantz, D. E.. House Rats and Mice: U. S. Dept. Agr., Bur. Biol. Surv.
Farmers' Bull. 896, 20, 1917.

THE BROWN RAT 59

between the actually harmful and the harmless birds of prey and
predaceous mammals. Too often the farmer is inclined to think
that because one hawk, or owl, or skunk destroyed a fowl for him,
all hawks, owls, and skunks should be killed since all are harmful.
As has before been indicated in this bulletin hasty conclusions
should not be drawn; and if the indiscriminate hunter of these
animals will take the trouble to investigate he will find that with
exceedingly few exceptions all are worthy of his protection, and
pay, many times over, for an occasional fowl. The fact that an
individual may have the perverted habit of destroying poultry
ought not to be taken as sufficient evidence for condemning the
species as1 a whole.

Most of the larger hawks and owls destroy considerable numbers
of rats. Hawks feed during the day time and in open fields where
rats often go for food ; in mornings and afternoons during summer
these alert birds of prey find and destroy the rodents. The red-
tailed hawk, broad-winged hawk, red-shouldered hawk, rough-legged
hawk, and the marsh hawk are particularly effective in this work.
Owls hunt largely in the evening and at night when mice and rats
are abroad about buildings. The barn owl is a most efficient de-
stroyer of rats and mice as well as one of the most wantonly perse-
cuted of this group of predaceous birds on account of its large
size and peculiar appearance. It often makes its home about farm
buildings, and in such surroundings enjoys ample opportunity for
securing rats and mice. Needless to say it is one of the most useful
birds on the farm and deserves better treatment than it usually
receives. The screech owl, great horned owl, barred owl, long-eared
owl, and short-eared owl all destroy rats and mice taken either from
the fields or about buildings. While the great horned owl, also oc-
casionally takes a fowl or game bird, the good which it does in de-
stroying rodent pests far outweighs the comparatively small amount
of actual damage done.

Of the predaceous mammals, skunks are most efficient as ratters
and quickly destroy or drive away rats and mice from the premises.
These animals usually hunt at night, and if poultry is properly
housed it is safe from them. If skunks are not disturbed they will
remain in the vicinity of farm buildings as long as mice and rats
may be secured for food. Weasels and minks also destroy many rats
and mice, but are prone to attack poultry that is not properly pro-
tected from them and sometimes kill apparently merely for the
love of killing.

60 RODENTS OF IOWA

Domestic dogs, of the terrier variety, with a very little train-
ing usually make good ratters and are of value in destroying these
rodents about farm buildings, warehouses, ete.

Domestic cats are usually so well fed that they will not make
an effort to destroy rats, and, moreover, not many cats will attack
a full grown rat. Some cats that will not attack rats will destroy
mice; but the half -wild cats that roam the fields at large are
usually such inveterate destroyers of young birds and poultry as
to counteract their efficiency as mousers.

Tame ferrets are sometimes employed in catching rats, but the
services of a well-trained dog are needed in addition, the rats being
driven out by the ferret and then killed by the dog. Unmuzzled
ferrets sent into the rat burrows are likely to remain quiet after
sucking the blood of the rat or to escape through some unlooked-
for opening and be lost. Ferrets, too, are delicate creatures and
need more or less attention ; so that this method of ratting is scarcely
likely to produce good results unless the owner of ferrets is expe-
rienced in handling these animals.

Precautionary Measures. — Since house rats and mice are much
alike in food habits and in the situations chosen for nesting and
rearing their young the following precautionary and control meas-
ures are applicable, in general, for either pest. In the control of
rats and mice, as with the control of other rodent pests, precau-
tionary and preventive measures are more easily effected than are
remedial measures after the pests have once gained access to and
begun to breed in places offering abundant food and safe retreats.

The use of cement in the construction of modern buildings pre-
sents many advantages in the way of eliminating favorable hiding
places for rats and mice. Care should be taken that basements and
cellar windows left open for ventilation are properly screened and
that outer doors are not left open. The lower edges of outer doors
to such places as markets and warehouses should be faced with
metal plates through which the animals cannot gnaw. Openings
in walls, around steam, gas, or water pipes should be closed with
concrete. Rat holes can also be closed permanently in this manner.
Sometimes bits of glass or crockery are added to the cement to be
used for this purpose. Concrete walls, footings, and floors in base-
ments are all effective in keeping these pests from buildings.

Wooden floors, sidewalks, and porches built close to the ground
offer safe hiding places for rats and should be replaced by others

THE BROWN RAT 61

of cement construction. Wooden floors of buildings and porches
should be some distance above the ground.

Henry Field, of the Field Seed Company at Shenandoah, informs
the writer that since the wooden floors of his warehouses have been
replaced with cement floors, and the basements floored and lined
with cement, he- has sustained little loss through the work of either
mice or rats. The problem of keeping the place in a cleanly condi-
tion has also thereby been simplified.

In the construction of farm buildings such as stock barns, pig
pens, and poultry houses the floors and supports should be of con-
crete. The above animals may be kept from actual contact with the
cement by the use of dry sand or a wooden floor laid over the con-
crete. Corn cribs and granaries may be built entirely of concrete,
or, by the use of a galvanized wire netting placed all round the
inside or outside of a new or old -crib, mice, rats, and sparrows
may be excluded. The netting should be of not greater than half-
inch mesh and of sufficient weight to resist the teeth of rats. If
sparrows are not to be excluded the netting may be carried up
three feet from the ground and a belt of sheet metal a foot wide
nailed along its upper edge. Cribs and granaries may be built upon
smooth posts high enough to prevent rats from obtaining a foot-
hold and at the same time high enough to hold the floor well above
the ground, say fourteen to twenty inches, the floor being then pro-
tected from below by wire netting or sheet metal. The floors should
be as tight as possible, so that the grain may not leak through and
attract the rats. By placing the floors entirely above the earth,
thus leaving no hiding places for the rats, there is little induce-
ment for the pests to make such places their abode.

An important measure in the repression of rats and mice is the
keeping of food materials from them. Old buildings which can-
not be easily and cheaply made rat-proof by some of the methods
suggested above may be torn down and replaced with new ones as
a matter of real economy. If the animals can secure food easily they
breed more rapidly and the difficulties in putting- into effect suc-
cessful control measures are increased. Foodstuffs, forage crops,
clothing, furniture and the like, if stored for a time are subject to
attack with more or less resultant loss and damage. Food supplies
in cellars, pantries, and kitchens may be kept safe by placing in
wire-covered, rat-proof containers. The proper collection and dis-
posal of garbage and waste from homes, hotels, cafes, slaughter

62

RODENTS OF IOWA

houses, and other places where such materials accumulate is also
an important factor in rat repression. Wastes, of whatever kind,
should be collected in metal containers furnished with covers, care
being taken that the covers are always in place. Such containers
should be emptied frequently and the contents utilized in some use-
ful manner or promptly burned.

Control Measures. — Mice are more easily trappM than rats; but
with either animal it is difficult to obtain results if food is plenti-
ful. Rats are also more cunning- and suspicious than mice and this
'fact contributes further to the difficulty of this method of control.
However, constant, consistent and concerted effort in trapping is
one of the best means of controlling the pests.

One of the most efficient traps is the so-called "guillotine" trap

I<IG. 13. — Guillotine trap made entirely of metal. (From U. S. Department of
Agriculture, Bureau of Biological Survey.)

made in various styles and sizes, those of simple construction being
preferable. Traps composed entirely of metal are best. In choos-
ing a bait it is best to select some food which is not found in the
vicinity. The following baits have been found excellent: Bacon,
wienerwurst, oatmeal, toasted cheese, and bread (with butter), fish,

THE BROWN RAT 63

fresh liver, raw meat, apples, carrots, corn, and sunflower or pump-
kin seeds. In winter fresh vegetables such as cucumbers, tomatoes
and egg-plant make excellent baits. Such baits may be placed upon
the trigger plate, or the trigger wire may be bent outward and the
bait placed under it. If a guillotine trap with a wooden base is
used oatmeal has been found to be a most excellent bait. A num-
ber of such traps of small size thus baited will be found effective in
ridding a dwelling of mice. Good results should not be expected
with a small number of traps, but in an ordinary house or barn
several dozen should be used.

If considerable numbers of rats are present in a building the
large wire cage traps may be used effectively ; but care should be

FIG. 14. — Guillotine trap with wooden base and trig'ger plate. (From U. S. De-
partment of Agriculture, Bureau of Biological Survey.)

taken in purchasing such traps to see that the wires are of suf-
ficient weight so* as not to be bent by the 'confined rats. Such traps
should be partly concealed, carelessly, and without obvious at-
tempt. A board placed over the trap and an old cloth or sack or
a bunch of straw loosely throwrn over it will answer very well.
Sometimes good results are obtained by placing the entrance of the
trap opposite a rat hole, fitting it closely so that the rats in order
to leave the hole musjt enter the trap. These cage traps may also be
baited and left for several nights until the rats become accustomed
to enter them Avhen they should be freshly baited and closed. If
a single rat is caught it may serve as a decoy to attract others.
Cage traps are most effective in securing young rats, for after a
little time the adult animals become Suspicious of the trap and
will not enter. The traps should be handled as little as possible;
and some trappers make a practice of subjecting the trap, whether
cage, guillotine, or steel, to .the smoke of a fire and then of placing it

64

RODENTS OF IOWA

with a stick or other instrument. Sometimes also gloves are worn
in the setting of these traps.

The common spring steel trap (No. 0 or 1) may be used, but since
the rat is usually caught by the foot its squeals frighten the other
rats and they are made more wary. Such traps may be set in nar-
row runways or at the openings of burrows and covered lightly by
oats or other grain. Care should be taken to keep the trigger plate
free from grain. A food which is not commonly accessible will
prove to be the best bait ; so that in and around a slaughter house
or meat market, vegetables or grain will serve best, while in a barn
or granary a bait of meat will give best results. The bait should
be kept fresh, should be handled as little as possible, and should
be changed when a given kind no longer .continues attractive. Of
course other foods should be made as inaccessible as possible while
trapping is in progress.

The barrel trap is reported, to have been used with considerable
success in some places and the method of using it may be briefly
mentioned. The rats are first attracted to a given place for several
nights by baits placed upon the tops of barrels covered with heavy
brown paper or with a light wooden top. After the rats become
accustomed to this method of feeding a cross is cut in the paper

FIG. 15. — Barrel trap; 1, with stiff paper cover; 2, with hinged cover; a, stop;
6, baits. (From U. S. Department of Agriculture, Bureau of Biological
Survey. )

and the rats on coming to the usual place fall into the barrel. In
the case of the wooden-topped barrel, the cover is hinged on a rod ;
and the baits are fastened to the cover which is properly weighted
so that it will turn with the weight of the rat, and after the animal
has been dropped into the barrel will again come to a horizontal
position ready for the next victim. A stop is placed on the side

THE BROWN RAT 65

of the barrel opposite the baits to prevent the lid from tilting in
more than one direction.

Professor C. C. Nutting- informs the writer of a unique but ap-
parently successful method of driving out rats from a dwelling.
He has tried it and his experience may be briefly mentioned here.
Upon returning to his Iowa City home in late summer at the close
of his vacation, Professor Nutting found the cellar of his house
literally overrun with rats. Holes and burrows had been made in
the walls and floor of the cellar and the. animals were evidently
well satisfied with their lot. Upon discovering this state of affairs,
Professor Nutting promptly placed about two tablespoonfuls of red
pepper in each burrow and rat hole that he -could find. The result
was that 'every rat on the premises disappeared very shortly and
reinfestation has not since occurred.

Poisons offer one of the quickest, surest, and most efficient meth-
ods of 'combating mice and rats, especially around barns and out-
buildings ; but the odor arising from the dead animals renders this
method inadvisable in occupied dwellings. Extreme caution should
be observed in the use of any poison, and care should be taken
not to place it or the poisoned baits where children or domestic
animals of any kind can reach it. Pains should be taken, also,
to see that the bodies of any rats or mice that have been killed by
poison have been disposed of either by burying or burning them.

Strychnia sulphate (dry crystals) may be inserted into such baits
as raw meat, toasted cheese, or wienerwurst cut into pieces. The
baits are then placed along the runs or burrows. A strychnin syrup
is easily made, and oatmeal, wheat or corn poisoned by soaking in
this semi-liquid. The syrup is prepared by dissolving a half ounce
of strychnia sulphate in a pint of boiling water; a pint of thick
sugar syrup is then added, and the whole stirred thoroughly. If
oatmeal is used as a bait, it should be thoroughly moistened with
the syrup ; wheat, corn, or other grain should be soaked over night
in the syrup. Smaller amounts of this poison preparation can be
made by using the proportions given above.

Barium carbonate is a cheap, effective, and comparatively slow-
acting poison without taste or smell; and aftei rats or mice have
partaken of it they usually leave the premises in search of water.
This feature adapts the poison, in a measure, for use in occupied
dwellings. Oatmeal is a good bait, and mixed with about one-eighth
5

66 RODENTS OF IOWA

its bulk of barium carbonate and sufficient water to form a thick
dough is easily handled and distributed. The poison may also be
fed in the form of a dough made of four parts flour or meal to one
of the poison. It may also be spread upon moistened toast, fish, or
bread and butter. Such baite may be placed in small pieces along
and in the runs. If the first application does not bring the desired
results another bait should be tried. This poison has a corrosive
action upon the stomach lining.

Powdered white arsenic (arsenious acid) has long been used as
a poison for rats, but while some rats may be killed by it others
will survive and once recovered they will seldom be attracted a
second time. The baits mentioned above for use with barium car-
bonate or strychnin may be used with arsenic. A successful method
of using this poison is to take twelve ounces of corn meal and one
ounce of the arsenic to which are added the whites of enough eggs
to form a heavy dough.

Phosphorus is a commonly used poison, and the writer has used
it with a considerable degree of success. However, the phosphorus
pastes which may be obtained at the drug stores vary to such
a great extent in the proportion of phosphorus present that they
can scarcely be relied upon, while in some the amount of phosphorus
present renders the paste highly inflammable. Home-made prepara-
tions are liable to result in conflagrations. Phosphorus paste does
not prevent decomposition of the body of the animal which has
eaten it, neither do the animals leave the premises before dying.
On the whole phosphorus paste is not a satisfactory poison for ro-
dents, and its use in this respect is not encouraged.

Where rats infest buildings and yards occupied by poultry the
poisoned baits may be placed in a small wooden box over whieh is
set a considerably larger box, bottom upward, with one or more
holes in the sides sufficiently large to admit the rats. The pests
thus have access to the poison whil« the fowls cannot reach it.

Fumigation with carbon bisulphid is effective in destroying rats
in burrows in fields and along river banks and levees. Carbon
bisulphid is a highly inflammable liquid which evaporates rapidly
upon exposure to the air and gives off a poisonous vapor. It can
be used in fumigation only where the fumes can be confined suf-
ficiently so that the animals are asphyxiated, and for this reason is
not effective in most buildings. To fumigate rat burrows take a
wad of cotton or other absorbent material, saturate thoroughly with
the liquid and push into the burrow as far as possible with a stick.

THE BROlWN RAT 67

The opening should then be quickly packed with earth to prevent
escape of the fumes. Care should be taken that lighted cigars, pipes,
cigarettes, matches, and open lights are not brought near the carbon
bisulphid.

Hydrocyanic acid gas has been effectively used to destroy all
animal life in buildings ; and if properly used will successfully de-
stroy rats, mice, and insects. Since this gas, however, is extremely
poisonous to human life, this method of fumigation should not be
undertaken by an inexperienced person without following careful
and detailed instructions. Farmers' Bulletin No. 699 of the U. S.
Department of Agriculture, prepared by L. 0. Howard and C. H.
Popenoe and entitled ''Hydrocyanic Acid Gas against Household
Insects," will give details regarding fumigation with this poi-
sonous gas.

Cooperative and organized effort in the destruction of mice and
rats is of very great importance. Individual and sporadic effort,
while instrumental in reducing the number of pests locally, cannot
bring about large results for the animals soon come in from sur-
rounding localities where repressive and control measures have not
been in vogue. Whole townships, counties, and cities should give
continuous and united effort in the destruction of these pests in
order that permanent results be obtained. In the city of Mus-
catine a bounty of one cent each is offered on rats by the city coun-
cil. The bounty has been in force for about three years and has
had the effect of reducing, to a considerable degree, the number of
pests. While a municipal bounty is not recommended as an ex-
cellent control measure, it sometimes gives good results and draws
attention to the situation, so that cooperative work is likely to
meet with more popular favor.

Organized rat hunts, while effective at the time, are not of per-
manent value unless followed up by continued effort, which may
often be stimulated by the offering of prizes. Various civic and
citizens' clubs, Boy Scout troops, women's clubs and other organ-
izations can do profitable work by encouraging a continuous cam-
paign of destruction against the rat.

In conclusion, a summary of the important measures for repress-
ing and eliminating rats and mice as sriven by Lantz in Farmers'
Bulletin No. 896 may be pertinently included here:

"1. The requirement that all new buildings erected shall be
made rat-proof under competent inspection.

68 RODENTS OF IOWA

2. That all existing rat-proof buildings shall be closed against
rats and mice by having all openings accessible to the animals, from
foundation to roof, closed or screened by door, window, grating, or
meshed wire netting.

3. That all buildings not of rat-proof construction shall be made
so by remodeling, by the use of materials that may not be pierced
by rats, or by elevation.

4. The protection of our native hawks, owls, and smaller preda-
tory mammals — the natural enemies of rats.

5. Greater cleanliness about markets, grocery stores, warehouses,
courts, alleys, stables, and vacant lots in cities and villages, and like
care on farms and suburban premises. This includes the storage
of waste and garbage in tightly covered vessels and the prompt dis-
posal of it each day.

6. Care in the construction of drains and sewers, so as not to
provide entrance and retreat for rats. Old brick sewers in cities
should be replaced by concrete or tile.

7. The early threshing and marketing of grains on farms, so
that stacks and mows shall not furnish harborage and food for rats.

8. Removal of outlying straw stacks and piles of trash or lum-
ber that harbor rats in fields and vacant lots.

9. The keeping of provisions, seed grain, and foodstuffs in rat-
proof containers.

10. Keeping effective rat dogs, especially on farms and in city
warehouses.

11. The systematic destruction of rats, whenever and wherever
possible, by (a) trapping, (b) poisoning, and fc) organized hunts.

12. The organization of clubs and other societies for systematic
warfare against rats."

BLACK RAT.
Eattus rattus (LinnaBus).
[Mus] rattles Linnaeus, Syst, Nat., X ed., I, 61, 1758.

Description. — Color above sooty or plumbeous black; fur softer
and thicker than in the brown rat; the mixture of darker and
lighter over hairs gives the animal a shiny appearance; color below
paler than above; feet brown; tail longer than head and body.

Measurements. — Total length, 14.90 inches; tail vertebra?, 8.10
inches; hind foot, 1.40 inches.

NORTHERN WHITE-FOOTED MOUSE 69

The black rat is not so stout as the brown rat and has a longer,
more pointed head and larger and broader ears, while the tail is
longer than the head and body together.

The black rat was carried from Europe to South and Middle
America about 1554 but the time of its arrival in the North Amer-
ican colonies is not definitely knowrn. Apparently it had become well
established in the settled districts by the beginning of the eight-
eenth century ; but with the appearance of the brown rat the num-
bers of the black rat began to decrease, and in most localities it is
no longer present.

In the United States the black rat is still found in some parts
of the South; a few colonies occur in Canada and in some states
east of the Mississippi. At some seaports like San Francisco and
the immediate coastal islands, it is probable that numbers of this
species are introduced in shipping from t,he far East, but these
individuals are usually destroyed before they have much oppor-
tunity to reproduce their kind. So far as our neighboring states
are concerned the black rat has been recorded from Wisconsin, In-
diana, Tennessee, and Kentucky. The species was first recorded
from Iowa by Professor Herbert Osborn in 1888, and to the record
he adds the statement, on the authority of Jordan, "being sup-
planted by preceding" [Rattus norvegicm] .9 This rat is again re-
corded from the state by the same author in 1891, without com-
ment.10 The writer is not familiar with any other records of the
occurrence of this form in Iowa, and it is probably no longer found
within our borders.

NORTHERN WHITE-FOOTED MOUSE. WOODLAND DEER

MOUSE.

Peromyscus leucopus noveboracensis (Fischer).

[M us sylvaticus] Noveboracensis Fischer, Synopsis Mamm., 318,
1829.

Description. — General color above brown, slightly darker along
middle of back ; ears dusky, narrowly margined with white ; whis-
kers blackish above, white below : tail thickly clothed with hair,
brownish above and gradually shading into white below ; feet white ;

9Osborn, Herbert, Catalogue of the Mammals of Iowa, Proc. la. Acad. Sci.,
I, 43, 1888.

10Osborn, Herbert, A Partial Catalogue of the Animals of Iowa : Ames, Iowa,
5, 1891.

70 RODENTS OF IOWA

color below white, entirely concealing the slaty undercolor; entire
pelage long and soft.

Measurements. — Total length, 7.00 inches; tail vertebrae, 3.00
inches; hind foot, 0.87 inch.

This is the best known of the white-footed mice, since it is most
common in thickly populated regions of the United States, includ-
ing such districts in Iowa. The name "deer mouse" apparently
has been given this animal on account of the supposition that the
seasonal change in color 'corresponds to that of the Virginia deer.
Adult mice do not show so much seasonal difference as the deer,
the main difference being in juvenile and adult pelage. "While the
pelage of the adult mouse is almost constantly changing such change
is due to wear and fading, there being but a single annual molt,
which occurs in summer or early fall.

Habits, Distribution, Etc. — The northern white-footed mouse is
partial to wooded areas, although in summer it is often found in
pastures where old stumps and bushes occur. In no case, how-
ever, is it found far from woods. Sometimes old corn and small
grain shocks along the edges of woods are used as homes. This
mouse is mainly nocturnal in its habits, though occasionally it goes
about during the day. It wanders about freely and makes no beaten
runways, though undoubtedly it often utilizes those made by other
rodents, especially meadow mice. This form burrows very little,
the most ambitious undertaking in this direction usually being a
simple, shallow runway under a log or other object. Though liv-
ing largely on the ground it is to some extent arboreal and can
climb trees almost as well as a squirrel.

The nests are built in or under an old hollow log or stump, in
some cases in a pile of brush or in bushes. Often these mice occupy
the deserted nests of woodpeckers or chickadees, and again they
may use either temporarily or permanently a bird's nest in a small
bush. Frank C. Pellett reports having found them living in hol-
low limbs in the top of a large tree. The nest is usually composed
of small twigs, leaves, and grass and when on the ground is reached
by short, underground tunnels. On April 13, 1914, near Bayfield,
the writer turned over a small hollow log and found a nest of this
form occupied by a single individual. The nest was composed en-
tirely of grass, and was on low land, near water in a sparsely
wooded area; the nearest buildings were about one mile distant.

NORTHERN WHITE-FOOTED MOUSE

71

This white-footed mouse does not hibernate, but is active through-
out the winter, and stores up grain and seeds for use during cold
weather. It is very prolific, usually bearing from four to six young
at a time, and it breeds throughout the year; so that, ordinarily,
two or three litters are produced in a season.

FIG. 16. — Map showing locality records of —

1. Northern White-footed Mouse (Peromyscus leucopus noveboracensis) .

2. Prairie White-footed Mouse (Peromyscus maniculatus bairdi).

This mouse is distributed throughout the state, and in some
localities, particularly in wooded areas, is quite abundant. The
localities represented by specimens are Wayland, Bayfield, Bur-
lington, Fairport, Thayer, Wall Lake, Iowa City, Charles City,
Homestead, and Newton. It has also been recorded from Knoxville,
Redfield, Council Bluffs, and from Clay and Palo Alto counties.

Food Habits, Economic Importance, Etc. — The northern white-
footed mouse does not feed to any great extent upon green plants
as do the meadow mice; its food consists mainly of nuts, acorns,
the seeds of maple and other trees, grain in the fields, and seeds
of noxious weeds. It is also very fond of basswood seeds, the
pits of wild cherries, and the seeds of many wild shrubs and
grasses. ' ' In wooded regions or on waste land, where it commonly
lives, it is not very injurious to agriculture ; but when living about
the edges of cultivated ground it sometimes devours or carries away
grain in considerable quantities. ... It occasionally gnaws the

72

RODENTS OF IOWA

bark of young fruit trees or nursery stock, but such harm is more
often due to meadow mice (Microtus) .'ni

This species often enters out-buildings and even houses, particu-
larly in rural districts and communities in which the house mause
has not become established, for the latter mouse seems able to drive
away the white-footed form. In such places this mouse finds a com-
fortable living and pleasant quarters, but commits more or less

FIG. 17. — Field-Mouse skulls taken from pellets found under owl roost in Smith-
sonian tower, Washington, D. C. (From U. S. Department of Agriculture,
Bureau of Biological Survey.)

depredation in the way of cutting up cloth for nesting materials and
destroying foodstuffs and provisions of various kinds. Sometimes
damage is done in granaries and in hay and straw stacks. Since
this mouse is so prolific, and since it is mainly nocturnal in its
habits, with the result that it is not much attacked by hawks, its
numbers in a given locality may increase considerably above normal
with resulting injury to agricultural interests. However, in no case
has the writer heard specific charges of serious damage against the
northern white-footed mouse in the state, although it is probable

"Lantz, D. E.> N. A. Fauna No. 28, 27, 1909.

PRAIRIE WHITE-FOOTED MOUSE 73

that damage may have occurred and have been attributed to the
house mouse. Of course owls, weasels, and the larger harmless
snakes destroy numbers of white-footed mice; and, in addition,
domestic dogs and cats occasionally kill them. They can be kept off
one 's premises only by constant vigilance, since any decrease in the
supply is immediately made good by invasion from neighboring,
woods and fields. When these mice infest houses and other build-
ings, they may be destroyed by trapping (the common snap traps
are good), or by poisoning. Strychnin in the form of strychnia
sulphate is one of the best methods of poisoning. One ounce of the
poison is used for one-half bushel of wheat. The strychnia sulphate
is first dissolved in a pint of hot wrater, after which a pint of heavy
syrup or molasses is added. This poison fluid is now poured over
the wheat and the mass stirred until each grain is coated, when
the whole is left for from twelve to twenty-four hours before it is
distributed. Care should be exercised that birds and live stock are
not allowed access to the poisoned wheat either in bulk or after it
has been distributed.

PRAIRIE WHITE-FOOTED MOUSE. PRAIRIE DEER

MOUSE.

Per omy sens maniculatus bairdi (Hoy & Kennicott).

Mus badrdii Hoy & Kennicott, in Kennicott, Agricultural Report,
U. S. Patent Office (1856), 92, PL XI, 1857.

Description. — Winter: Color above brown mixed with black, the
latter confined to middle of back; sides paler than back; sides of
face paler than top of head; ears brownish black narrowly mar-
gined with creamy; tail sharply bicolor, black or blackish brown
above, white below; feet white; color below white or whitish, the
tips of hairs white, their bases slaty gray; the dark bases are not
concealed and this gives a grayish tinge to the under parts. Sum-
mer: The worn pelage becomes brighter and the dark dorsal line
reduced and changed to pale brownish.

Measurements. — Total length, 5.75 inches; tail vertebras, 2.45
inches; hind foot, 0.70 inch.

This form is similar to the northern white-footed deer mouse,
save that the ears and feet are smaller and the tail markedly shorter,
more thickly haired, and more sharply bicolor; in addition, the
general color is darker than in that species, and the entire animal
is decidedly smaller.

74 RODENTS OP IOWA

Habits, Distribution, Etc. — The prairie white-footed mouse seems
to be confined to the open prairie and cultivated fields of the Mis-
sissippi Valley. In Iowa it is distributed practically throughout
the state and seems to be at least no less common than the northern
white-footed mouse.

This mouse inhabits dry cultivated fields and prairies, and, to
some extent, is found in small sparsely wooded areas. Ruthven and
Wood report that the nine specimens secured in Clay and Palo Alto
counties ' * were found in burrows in stubble fields, pastures and on
the shores of lakes."12 Robert Kennicott, who many years ago
made extensive observations on this animal, reports as follows con-
cerning its habits : ' ' Not having on the prairies, the shelter found
by its timber-loving cousins in old tree stumps and trees this species
digs burrows. These are rather simple, with few or no side-pas-
sages, and often with but one entrance, the depth and extent being
variable, but never great. The nest is small, composed of soft grass,
etc., it is spherical, and the small internal cavity is entered through
a narrow opening on one side. In cultivated fields the burrows are
frequently dug at the roots of fruit trees, the bark of which is often
gnawed, sometimes causing great injury. In nurseries, fruit-trees
are often taken up and ' heeled in ' ; that is, laid down close together,
with the roots placed in a trench, and then 'covered in such manner
that they are kept safely in a very small space, and can be readily
pulled out when desired. The loose earth among the roots of these
offers an inviting habitation to the mice ; and, in nurseries infested
by them, they will be found burrowing in almost every lot of trees
thus buried, where they feed upon the bark of the roots, and thus
cause serious damage. In the fall, they are often found in corn-
shocks, making a nest among the stalks, though they do not so often
burrow under these as the arvicolae. But, during winter, they may
be tracked in corn-fields from their burrows to the neighboring corn-
shocks, which they have visited for food. In spring, the young are
always produced in burrows. During the summer, however, they
occasionally are observed in nests, under bits of wood or bunches
of hay, on the surface of the ground. In autumn, I have found
nests of the young in small burrows only a few inches below the
surface, or under an inverted sod. I have never observe! more
t^n one pair of adults occupying the same burrow; and, unlike

"'Ruthven, A G., and Wood, N. A., Proc. -la. Acad. Sci. XIX, 204, 1912.

PRAIRIE WHITE-FOOTED MOUSE 75

the Mus leucopus [White-footed mouse] this species never appears
to be gregarious. . . .

' ' I have found the young in March and April, and observed two
females, each with five young, apparently but a few days old, about
the tenth of November, while they are found in every intervening
month. In nearly every instance within my observation the number
of young produced at a birth has been five. I once found six, and
have at times, though rarely, seen three or four. The young are
attached to the teats, as in the species last described ; and a female
was seen to carry five for several rods in this way, jumping along
rapidly despite their weight. As soon as they are able to take care
of themselves, the young leave the mother. In summer, I have sev-
eral times found one apparently but a few weeks old, living 'alone
in a nest made by himself. In spring, I have always found the old
male living with the female and young; but during the summer, I
have sometimes observed the male leading a solitary life, and the
females and young in burrows by themselves. The food of this
mouse, on the prairies, appears to be herbaceous plants, with their
seeds ; but I have been unable to see that it ever digs for roots. It
is interesting to observe that this, like the Mus leucopus, seeks its
food on the top of the ground, running on the snow in winter in
search of seeds, and collecting them in autumn instead of roots,
when it travels as often by springing over the grass as by running
through it. This mouse probably feeds more or less upon insects,
as it is carnivorous in captivity; though some specimens are much
less so than others."13

On November 10, 1917, the writer received from Yinton an adult
female example of this form along with four young apparently less
than a week old. The latter were scantily haired and had the eyes
closed. This family was found in a burrow about five inches deep
in the soil. No evidences of stored food were found in the burrow.
The measurements of the young are as follows :

TOTAL TAIL HIND

LENGTH TERTEBE^ FOOT

Specimen No. 1 64 mm. 22 mm. 11 mm.

Specimen No. 2 60 mm. 23 mm. 11 mm.

Specimen No. 3 61 mm. 20 mm. 11 mm.

Specimen No. 4 60 mm. 20 mm. 11 mm.

NOTE — Since the specimens were so small the measurements are given
in millimeters instead of fractions of an inch.

13Hoy & Kennicott, in Kennieott, Agr. Kept, for 1856, U. S. Patent Office
Kept., 93-94, 1857.

76 RODENTS OF IOWA

Of course in localities where these mice are abundant they cause
some damage to grains, orchards, and nursery stock. Since they
are abroad during the daytime more than the preceding species,
they are subjected to the attacks of a greater number of enemies
than are the northern white-footed mice, a fact which serves to keep
down their numbers somewhat. Skunks, minks, weasels, hawks,
owls, crows, herons and bitterns, the larger harmless snakes, and
domes tic dogs and cats are all efficient in keeping down the num-
bers of this mouse.

Of the control measures which may be employed, those offered
in the discussion of the preceding species will be found effective.
A further suggestion as to a method of poisoning may be mentioned
here and one which has the advantage of not placing in danger the
lives of domestic animals and birds. Instead of scattering the grain
on the ground, place the poisoned wheat in short pieces of drain
pipe, having a diameter of one and one-half inches. The pipes are
then placed on the ground near the burrows or nests where the mice
may readily enter.

This seems to be the more abundant of our white-footed mice, and
many specimens are at hand from Corning, Jefferson, Thayer, Wall
Lake, Ottumwa, Melvin, "Waukon, Rodman, Ocheyedan, Logan, and
Homestead. The species has also been recorded from Knoxville and
from Clay and Palo Alto counties. See also the map on page 71.

PRAIRIE HARVEST MOUSE.

Reithrodontomys mcgalotis dychei Allen.

Reithrodontomys dychei Allen, Bull. Am. Mus. Nat. Hist., VII,
120, 1895.

Description. — Winter: Color above brownish buff mixed with
black, the middle line above in many cases noticeably darker; sides
grayish buff, the lateral line on some specimens well marked ; ears
brownish, thinly clothed with buffy hairs on inner surface, a tuft of
brownish buff hairs in front of their bases ; color below white ; feet
white; tail dark brown above, white below. Summer: -Colors less
strongly contrasted and the general color browner.

Measurements. — Total length, 5.25 inches; tail vertebrae, 2.25
inches; hind foot, 0.65 inch.

PRAIRIE HARVEST MOUSE

77

This little mouse has somewhat the appearance of Goss 's lemming
mouse; but the present form is browner above, lighter below, lacks
the dusky mark at the base of the whiskers, and has the groove on
the upper incisors (front teeth) near the middle of the tooth rather
than near the outer edge. In addition, the molars of the upper jaw
are furnished with rounded points or tubercles on the crowns ex-
tending in two longitudinal rows, in place of the irregular triangles
shown in Goss's lemming mouse.

FIG. 18. — Prairie Harvest Mouse. Photo from life by Prank C. Pellett.

Habits, Distribution, Etc. — The harvest mice, to which group the
present form belongs, all live in more or less neglected, open, grassy
fields and along the edges of cultivated fields. Although they live
for the most part above ground, sometimes burrows and crevices are
used in which to construct their nests. These nests are built of
grasses lined with soft material. The prairie harvest mice sometimes
travel in beaten paths of their own making or in runways made by
meadow mice. They do .not hibernate and are about both at night
and during the day.

The prairie harvest mouse molts only once a year, in late fall, but
marked changes in pelage are to be noted from other causes, namely,

78 RODENTS OP IOWA

fading and wear. Not much evidence of wear is shown before early
spring; but as the tips of the hairs wear off the pelage becomes
redder, and by the middle of the summer it shows indications of con-
siderable fading.

Grain, seeds, and green vegetation form the principal articles of
diet of the prairie harvest mouse. From the fact that it prefers
more or less neglected areas overgrown with native plants which are
of no value or of only slight value to the agriculturist it is evident
that, in Iowa at least, this mouse does little damage. Add to this the
fact that it is apparently not common in any locality and the likeli-
hood of damage is also lessened.

In Utah the species is reported as causing some damage by climb-
ing grain stalks and cutting off the heads. It is also reported that
in eastern Kansas this form is found under shocks of wheat and
corn in the fall and that in such situations it takes some grain.

This is a western form that is apparently working its way to the
east and north ; the records given below indicate that it is pretty
generally distributed throughout the state, although nowhere does it
seem to be abundant or even common.

Specimens are at hand from the following localities in Iowa:
Iowa City, Wall Lake, Atlantic, Ottumwa, Tama, Logan, and Jeffer-
son. This form has also been recorded from Fairport, Hillsboro, and
Palo Alto county. These records indicate that the prairie harvest
mouse is distributed rather sparingly over practically the entire
state ; though Mr. Pellett reports that it is common in the vicinity
of Atlantic and he has several specimens in his collection from
that place. See also the map on page 107.

MEADOW MOUSE. MEADOW VOLE.

Microtus pennsylvamcus pennsylvanicus (Ord).

Mus pennsylvcmica Ord, Guthrie's Geography, 2d Amer. ed., II,
292, 1815.

Description. — Color above reddish brown to yellowish chestnut,
mixed with blackish hairs; sides lighter, the lower sides yellowish
brown ; feet brownish with six calloused tubercles on the soles ; tail
dark above, paler beneath, and more than one-third the length of
head and body; color below grayish white, on some specimens
faintly washed with cinnamon brown.

Measurements. — Total length, 6.50 inches: tail vertebrae, 1.70
inches ; hind foot, 0.85 inch.

THE MEADOW MOUSE 79

This is our most common representative of this section of the fam-
ily; and, in addition to the characters above mentioned, it is to be
distinguished from the following closely allied form by the number
of teats, which is eight. In winter the fur is longer and duller col-
ored than in summer.

FIG. 19. — Meadow Mouse caught in a guillotine trap. (From U. S. Department

of Agriculture.)

The meadow mice proper, of which there are three forms occur-
ring in the state, and of which this is the first to be discussed, are to
be recognized in general by their stout bodies, the short, round and
hairy tail, the blunt, rounded muzzle, and the short ears, which in
winter are almost concealed by the fur. The fur is long, that of the
back being mixed with still longer hairs.

Habits, Distribution, Etc. — The meadow mouse is common
throughout the state in moist meadows and in the grassy borders
of marshes and wooded swamps. It is not uncommonly found in
dry pastures, cornfields, uncultivated or waste fields, and in open
spaces bordering timber land. Most meadows are infested with these
animals, and in the proper situations their trails are quite evident.
In swamps these paths often cross mud flats and even shallow water,
and where deep snow has melted or where dry grass has been burned
off the network of runways can be seen without difficulty. In the
construction of these trails meadow mice utilize many kinds of low
shelter, such as fallen weeds, leaves, and grass under which the
trails take on the nature of half-tunnels. These trails lead to the
roots of food plants and to underground nests, and are also used as

80 RODENTS OP IOWA

places of refuge. The meadow mouse is often seen in daytime, and
is not so nocturnal in its habits as are many of the related forms. It
is especially active in the evening and early morning.

The nest is usually constructed in burrows1 which follow along
under clumps of grass above the surface of the damp ground. It
is made up of grass or strips of weeds, coarser materials being used
on the outside and finer stuff within. Each nest has a small en-
trance hole near the bottom from which run two or more trails.
One of these often leads to an underground tunnel opening some dis-
tance from the nest. Nests in which the young are born are usually
lined with some soft material such as the "cotton" from the milk
weed or "•cat-tail." Such nests are ordinariy placed in under-
ground burrows. If a nest is destroyed a new site is immediately
chosen, fresh materials are secured, and another domicile con-
structed often in a single night. When the home is disturbed the
occupants rush about without much idea of where they are going,
and are as likely to go towards the source of danger as away from it.
Apparently their eyesight is not good in the sunlight. If a way of
escape is not evident, they will put up a fight with claws and teeth.

Ordinarily two, in some cases three litters of young are produced
in a season, the number in a litter ranging from four to eight with
six the average number. * The young are born blind and hairless.
The breeding season extends over most of the year except midwinter.
D. E. Lantz says: "The common meadow mouse (M. pennsylvani-
cus) is one of the most prolific of the American species. If six
young, the average number, are produced at a birth, and four litters
in a season, and if no enemy or disease check the multiplication, the
increase would be appallingly great. A single pair and its progeny
would in five seasons amount to over 2,000,000. This calculation is
conservative being based on the- theory that the young of one sea-
son do not breed until the next year — an assumption that is likely
to be incorrect; for, the animals mature very quickly, and the
young born in spring probably breed in the fall of the same season.
If a thousand pairs of meadow mice survive a winter in any local-
ity, it is easy to understand how, after two or more seasons of unin-
terrupted increase, they might become a menace to agricultural in-
terests."14

Dr. C. H. Merriam in discussing this species says: "In the be-
crinning of winter, when the ground is frozen for some distance be-

14Lantz, D. E., Meadow Mice in Relation to Agriculture: Yearbook, U. S.
Dept. AgT., 367, 1905.

THE MEADOW MOUSE

81

low the surface, it abandons its burrows and lives entirely above
ground. Its nests of dry grass then lie flat upon the surface, with-
out attempt at concealment and are soon buried in the snow. As
winter advances and the snow becomes deeper, the Meadow Mice
regularly betake themselves to their nests for rest. The heat from
their bodies soon melts the snow in contact with and immediately
adjoining the nests, which, from the continued operation of the
same cause, come to be surrounded by slowly-growing, dome-shaped
chambers. These increase in size until the Spring thaws in March
and April, melt away their roofs, thus admitting the light and cold.
They are then deserted."15

FIG. 20. — Map showing1 locality records of —

1. Meadow Mouse (Microtus pennsylvanicus pennsylvanicus) .

2. Prairie Meadow Mouse (Microtus ochrogaster ochrogaster) .

3. Woodland Vole (Microtus pinetorum nemoralis).

This form has been included in the earliest lists of Iowa rodents
and is one of the most abundant species of the group. It is found
in practically every locality in the state. Specimens are at hand
from the following places: Melvin, Thayer, Atlantic, Jefferson,
Waukon, Charles City, and Iowa City. It has also been recorded
from Knoxville and Luxemburg.

Food Hdbiis, Economic Importance and Control Measures. — In
summer the food of the meadow mouse consists mainly of green

15Merriam, C. H., Mammals Adirondack Region, 272, 1886.
6

82 RODENTS OP IOWA

vegetation and of the roots and seeds of grain and grasses. In win-
ter grain and various kinds of roots are substituted for the leaves-
and stems. If green vegetation is lacking, young apple orchards,
forest trees, or shrubbery are often attacked if they are convenient
and considerable damage is done. Such depredations occur most
often in winter, though they are not confined to this season, for
summer girdling of trees has been noted in many instances.

"Stomach examinations show that in addition to bark, green
leaves, and seeds of grasses and sedges, field mice eat all kinds-
of bulbs, tubers, and roots and occasionally animal food. The
larger aquatic species are said to eat mollusks, and crayfish. When
a number of these mice are kept in confinement, the stronger
animals usually devour the weaker, and our field naturalists have
frequently noted that trapped field mice are devoured by their
brethren

"It has been calculated that each adult meadow mouse requires
from 24 to 36 pounds of green vegetation per year. It is thus ap-
parent that the total amount eaten by the hordes that ordinarily
infest the meadows, swamps and forests of our country is incal-
culable, and is a steady drain upon the resources of the farmer.""
(Lantz, I. c. 368).

In addition to the kinds of food mentioned, the meadow mouse
feeds to a considerable degree upon roots of wild morning-glory,,
cat-tails, and sweet clover.

Numerous complaints have come in from various parts of the
state concerning depredations upon trees, pastures, and gardens by
meadow mice. Damage is often more widespread than is ordinarily
believed, since injury actually caused by the meadow mice is often
attributed to rabbits and gophers. Damage done by meadow mice
can usually be recognized by the small, narrow tooth-marks and by
the fact that it is lower down on the trees than that ordinarily done
by rabbits. In consideration of the great prolificacy of the species
and the large amount of food required by a single individual during
a year it is evident that where local conditions have been favorable
to an undue increase of the animals considerable loss to agricul-
tural interests is sure to follow. Where meadow mice are present
even in normal numbers) the loss though not serious may be worthy
of consideration in these times of conservation.

The meadow mouse works under the snow in winter, burro wing-
along the roots of clover, timothy, and other plants, often destroying-

THE MEADOW MOUSE 83

.an entire meadow. Damage is more likely to occur where the
growth is long and thick than in closely pastured meadows. This
sort of damage is most noticeable in late winter or early spring.

Meadow mice also do much damage to truck crops, and are espe-
cially destructive to strawberry, raspberry, currant, blackberry, and
rose bushes and also to grape vines. Since the various berry Leds
just mentioned are often mulched, the material thus used affords
hiding places and covering for the burrows. The animals are espe-
cially fond of the crowns of strawberry plants. Many growing
vegetables, such as potatoes, beets, parsnips, carrots, celery, etc.,
are attacked by meadow mice, and in autumn wrhen these vegetables
are left in piles for a few days considerable damage may be done
to them.

Corn, wheat, oats, rye, barley, and other growing crops are some-
times cut down and eaten. Corn is attacked mostly in the shock,
while some of the small grains also are thus attacked. At Osceola
and Corning such damage has been reported. Not only is the grain
eaten, but a portion is also lost or covered by earth so that, on the
whole, the net loss is often considerable. Alfalfa and 'clover also
are subject to the attacks of this mouse with considerable resultant
damage as reported from some parts of the state; fields of red
clover in some cases have to be plowed up and planted with another
crop.

The list of trees and shrubs attacked by these mice is a long
•one and includes practically all those grown by the horticulturist.
Among the trees most liable to injury are apple, plum, pear, peach,
cherry, sugar maple, oak, ash, <cottonwood, willow, and wild cherry.
•Other forest and fruit trees often suffer also. Damage to standing
nursery stock is often done when the ground is covered by deep
snow, under which conditions the trees are not only girdled but
the mice often burrow down along the trunk and attack the roots.
Trees recently transplanted from the nursery to the orchard seem
to be favorite objects of attack, although trees five to six inches
in diameter are also damaged and in some cases are killed. Since
small orchards are frequently planted for family use only and
hence, on account of the care demanded by other crops, in many
instances are neglected and grow up in weeds and grass, they afford
excellent hiding places for meadow mice and encourage them to
remain throughout the season in the presence of a continuous and
abundant supply of food.

84 RODENTS OF IOWA

Meadow mice inflict considerable damage in parks and lawns by
destroying shrubs, vines, bulbs and herbaceous plants. In some
cases the straw or grass used to protect delicate plants in winter af-
fords shelter and hiding places for the animals. Low hedges also
afford shelter under which the mice construct their burrows.

Meadow mice are not, for the most part, inhabitants of waste
lands, but of more or less cultivated regions; and in consideration
of their food habits as above described they must be considered as
injurious. That they are, to a slight extent, valuable as tillers of
the soil and as destroyers of noxious seeds cannot be denied, but
the slight good done in this way is more than offset by their destruc-
tive qualities. An invasion of these mice into an agricultural com-
munity would cause disastrous results, so that preventive and con-
trol measures should be continually encouraged and engaged in. In
view of the fact that the meadow mouse is so widely distributed,
that its habitats are usually inaccessible in ordinary control meas-
ures, and that the species is so prolific, complete extermination is
impossible. However, the numbers may be materially reduced in
any locality, so that crops may be rendered comparatively safe from
serious attacks.

There are a number of natural agencies which cannot be left out
of consideration in the repression of meadow mice. In this con-
nection Lantz says : * ' Climatic conditions so strongly influence the
natural increase of field mice that an understanding of their re-
lation to such increase is important. It has often been noticed that
the period of greatest abundance of voles follows one or more open,
warm winters succeeded by wet summers. If at the same time food
—particularly grain — is abundant, the most favorable conditions
for the increase of the animals are present, and the maximum num-
ber of young at a birth, as well as the maximum number of litters,
are brought forth. When grain is abundant the young of rome
species are said to begin to reproduce when only 2 months old.

"The continuance of favorable conditions for two or more years
is sure to be followed by an enormous increase of field mice, with
serious injury to crops.

* ' Very cold winters without snow and summers of long droughts
are unfavorable to the increase of field mice. Occasionally a severe
frost following a heavy downpour of rain destroys nearly all field
mice over large areas."16

"Lantz, D. E., An Economic Study of Field Mice : U. S. Dept Agr., Biol. Surv.
Bull. No. 31, 37, 1907.

THE MEADOW MOUSE 85

One reason that may be advanced as to the causes of increase of
rodent pests, meadow mice included, is the almost universal desire
of man to destroy any living -thing ; and many of the birds, mam-
mals, and reptiles thus thoughtlessly destroyed are among the forms
which are particularly effective in keeping down the numbers of
just such pests as we are now considering.

Of our wild mammals wolves, foxes, skunks, minks, weasels, and
shrews are efficient destroyers of meadow mice; and this coupled
with the fact that some at least, destroy noxious insects affords a
measure of compensation for the damage they do.

Of the birds hawks, owls, crows, shrikes, herons and bitterns are
very effective in the destruction of these mice. The red-tailed
hawk, the broad-winged hawk, and the sparrow hawk are worthy of
special mention; and what farmer has not seen a shrike pounce
down upon a, luckless mouse and carry him away to be torn to
pieces on the top of a post, or impaled upon a barb wire fence or
thorn of an osage-orange bush. Crows destroy young mice in the
nests and sometimes also kill the adults. Of the owls the barn owl,
long-eared owl, short-eared owl, and barred owl are especially effi-
cient as destroyers of meadow mice.

Snakes subsist largely upon a diet of insects and small rodents,
the latter standing second in importance on the bill of fare The
blue racer, bull snake, hog-nosed snake, and larger garter snakes
all destroy meadow mice. Most people do not realise the important
service that the harmless snakes do for agriculture, but, due merely
tO' their prejudice, destroy any and every snake wherever and when-
ever it is possible.

Domestic dogs and cats perform some service in the destruction
of meadow mice, but cats are liable to roam widely and in their
wanderings destroy young birds, w.hich seem to be preferred to the
mice.

Prevention of damage is more easily effected than a cure, and
some of the preventive measures that have proved most effective
will be briefly mentioned. Drainage of swamps and the clearing of
waste places will destroy the breeding grounds and situations of-
fering shelter to the mice. Clean cultivation in field, orchard and
nursery, one of the most effective of the preventive measures, is
highly recommended along with rotation of crops, while the burn-
ing of weeds, dry grass, and rubbish about those plots will eliminate
the hiding-places of the mice and lessen the likelihood of damage.

86 RODENTS OF IOWA

The clean mowing of grass lands and meadows, so that old grass
is not left over winter, also produces the same results. And finally,
the destruction of the natural enemies of the mice should be avoided
as largely as possible and not indulged in indiscriminately.

Destruction of trees or nursery stock may be eliminated by using
a lime-sulphur wash, which while very effective is also very cheap.
To make the wash use twenty pounds unslaked lime, fifteen pounds
flowers of sulphur, and water to make forty-five to fifty gallons.
Boil in an iron, kettle at least an hour before application, which
should be made by means of a brush or in the form of a spray while
the mixture is yet warm.

If trees have already been girdled by meadow mice, prevention
from decay and possible death is desirable. When these injured
places are subjected to the weather the bark dries and the trees die ;
while if the wounded places can be covered so as to exclude the air,
new bark will form and the injured parts will heal quickly. A
quick and efficient remedy is to mound up the trunks of the trees
with soil until the wound is covered, making due allowance for set-
tling. These mounds should remain in place all summer. Nursery
stock if only slightly injured by mice may in some cases be saved
by covering over the wounds with grafting wax or soil. The wounds
will heal over in one season.

Trapping is a simple and effective method of destroying meadow
mice, but is not adapted to large or heavily intested areas since re-
sults are slow. However, if the infested area is small, such as a
lawn or garden where the number of mice is limited, this method
is efficient, and if -persisted in the mice may be practically extermin-
ated. Meadow mice will not enter cage traps, so the guillotine or
simple wire snap trap which kill instantly are preferable. They
are to be set with or without bait across the runways of the mice.
Cornmeal or oatmeal may be used successfully as a bait.

The most satisfactory method of destroying meadow mice is
through the use of various baits poisoned with strychnin. To pre-
pare the poison dissolve a half ounce of strychnia sulphate in a
pint of boiling water and add a pint of thick syrup. Stir thor-
oughly. This quantity is sufficient to poison a half bushel of wheat
or corn, every grain of which should be thoroughly coated. If a
smaller amount is desired use the same proportions. The poisoned
bait should be placed under boards or other shelter so as to exclude
birds but admit mice. Pieces of drain tile about one and one-half

PRAIRIE MEADOW MOUSE 87

inches in diameter may be laid along the trails and the baits in-
serted with a spoon. Other baits, such as oatmeal and the seeds
of dandelions or sunflowers may be used in place of the wheat or
corn.

In winter a good method of destroying meadow mice as well as
rabbits is to cut small twigs from apple trees, dip them in the
strychnin syrup, and distribute them about the trees to be pro-
tected. This plan is recommended for orchards and nurseries.

Of course every precaution should be employed in the use of
these poisoned baits so that children, domestic animals, and birds
may not have access to them.

Another poison which has proved efficient in the destruction of
meadow mice is barium carbonate, which is very cheap and both
odorless and tasteless. "This poison is usually administered in
the form of a dough made of four-fifths flour or meal and one-
fifth barium carbonate. A little sugar is added to sweeten the mix-
ture and, if desired, a couple of drops of anise oil. The dough is

cut into small lumps the size of a large pea for mice The

poison may be fed also in moistened bread or oatmeal." (Lantz,
I. o. 58.)

Although meadow mice are active during practically the entire
year, winter is the most favorable time for poisoning them since
the supply of green food is then very limited. The mice are active
on mild winter days, and are most likely to partake of the poisoned
baits in the evenings of such days. Do not put out the poison on
the surface of the snow for the mice usually work under it.

Cooperation among farmers in the destruction of these pests is
the. most successful way of meeting the problem. By giving atten-
tion to the preventive measures suggested, much can be done in the
way of food and grain conservation; and the results will amply
repay those who have made the effort.

PRAIRIE MEADOW MOUSE. PRAIRIE VOLE.

Microtus achrogaster ochrogaster (Wagner).

HypudcHeus ochrogaster Wagner, Sehrebeis Saugthiere, Suppl.
Ill, 592, 1843.

Description. — Color above mixed light and dark brown, giving a
grizzled appearance; sides of body paler; feet brown with five
calloused tubercles on soles ; tail dark brown above, pale below, and
less than one-third the length of head and body ; somewhat dusky

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PRAIRIE MEADOW MOUSE 89

or blackish about the nose ; color below buffy gray or pale brownish
gray.

Measurements. — Total length, 6.00 inches; tail vertebras, 1.30
inches; hind foot, 0.80 inch.

This form may be distinguished from its closest ally in our rep-
resentatives of the family, the meadow mouse, by the somewhat
smaller size, the grizzled upper parts, and the buffy or brownish
under parts ; in addition, the prairie meadow mouse has but .five
calloused patches on the soles of the feet and the teats are six in
number,

Habits, Distribution, Etc. — The natural habitat of the prairie
meadow mouse is in dry fields and overgrown pastures of open
prairie country, and hence it is very likely to destroy cultivated
areas. Many native meadows, borders of corn and small grain
fields, as well as cultivated clover and alfalfa fields are overrun
with these animals. Wherever grasses and weeds are allowed to-

FIG. 23. — Apple tree killed by Prairie Mice. (From U. S. Department of Agri-
culture, Bureau of Biological Survey.)

grow and accumulate in dried matted bundles these mice are likely
to be found. Pastures and neglected orchards are favored situations
also, but if closely pastured the mice are driven elsewhere. If cul-
tivated crops are not in the vicinity, their trails in some instances

90 RODENTS OF IOWA

extend out for considerable distances into such pastures and or-
chards. Their food consists largely of roots of grasses and various
cultivated small grains, and in late fall and winter they do Con-
siderable damage to the roots of fruit trees and nursery stock. In
this latter respect this form probably causes greater damage than
does the common meadow mouse. In autumn prairie mice are often
to be found under corn shocks where they cause considerable loss of
grain. If cultivated crops are not to be had, these mice feed upon
the roots, seeds, and leaves of various wild plants.

The nest resembles that of the meadow mouse in its construction
and situation, but is somewhat smaller, while the trails and run-
ways are constructed much as described for that species. Prairie
mice seem to multiply less rapidly than meadow mice, since the
number produced in a litter is usually but three or four and the
long droughts of summer and continued extreme cold of winter
lessen the reproductive period.

Following is an extract from Robert Kennicott's account of the
habits of the prairie mouse in Illinois: "Their winter burrows on
the uncultivated prairie are often in old ant-hills, or, if not, the
earth thrown out of them forms little hillocks. They are not very
deep, seldom over six inches or a foot, but are remarkable for the
numerous and complicated chambers and side-passages of which
they are composed. In one of these chambers, considerably en-
larged, is placed the nest, formed of fine, dry e;rass. It is globular,
from four to six inches in diameter, and with but a small cavity
in the centre, which is entered by a very narrow opening on one
side. This burrow and nest are occupied in winter, and in ?.t at
least the first litter of young is produced in the spring; but in
the summer and fall these meadow-mice may be found in similar
nests in grass, above ground, in which the young are often, if not
usually brought forth. Nests formed under the snow in winter are
also occupied by them. From the burrows, innumerable runways
traverse the neighborhood, intersecting those from other burrows,
thus forming a complete net-work so that often scarcely a square
yard can be found in an acre not crossed by one or more of these
tracks. The runways of one pair may sometimes be traced five
or ten rods on every side. These roads are not only formed for use
in winter, when the ground is covered with snow, but are also em-
ployed as highways in summer. They are made above ground by
pressing down and gnawing off the grass, and the earth is often

THE WOODLAND VOLE 91

worn quite smooth and bare in those most used. The inhabitants
can travel easily along them at all times, in search of food, being
well concealed by the overarching grass. In winter, these paths are
formed on the ground, under the snow, as well as in the grass. The
mice do not inhabit prairie pastures, where the grass is eaten close
and affords them no cover. ' '17 .

Since the food habits, economic importance, and natural enemies
of the prairie meadow mouse are so nearly like those of the com-
mon meadow mouse, whatever has been said with reference to that
species is, in general, applicable here and the reader is referred to
that discussion for a consideration of those points. Control meas-
ures indicated for the meadow mouse are also practicable for the
prairie mouse so that they need not be repeated in this place.

This mouse seems to be as widely distributed as the meadow
mouse, and judging by the number of specimens received from vari-
ous localities it is as abundant as or even more abundant than that
species. Specimens have been received from Newton, Ottumwa,
Monticello, Wall Lake, Waukon, Logan, Corning, Melvin, Atlantic,
and Homestead. This form has also been recorded from Knoxville.
See also the map on page 81.

WOODLAND VOLE.
Microtus pinetorum nemorcdis Bailey.

Microtus pinetorum nemoralis Bailey, Proc. Biol. Soc. Wash.,
XII, 89, 1898.

Description. — "Upper parts dull chestnut, slightly lined with
blackish tipped hairs on back and rump, becoming paler on sides;
belly washed with cinnamon rufous over the plumbeous underfur;
tail indistinctly bicolor, agreeing with dorsal and ventral colors of
body ; feet thinly clothed with pale buf fy or sometimes dusky hairs.

"Measurements. — Type specimen: Total length 130 [mm.]; tail
vertebrae 24 ; hind foot 18. Average of five females and five males
from type locality : Total length 135 ; tail vertebrae 25 ; hind foot
18.1." (Bailey, I. c., 89-90.)

This is the largest of the so-called ' ' pine mice ; " its fur is longer
and duller than in the other forms occurring to the south and east
of Iowa.

Habits, Distribution, Etc.— The pine mice differ in habits from
the other members of the genus Microtus, and on account of these

"Kennicott, Robert, Agr. Kept, for 1856: U. S. Patent Office Rept., 98-99,

FIG. 24. — Root and trunk of apple tree from Laurel, Maryland, gnawed by Pine
Mice. (U. S. Department of Agriculture, Bureau of Biological Survey.)

THE WOODLAND VOLE 93

habits are not so well known as the typical meadow mice. The
woodland" vole naturally inhabits wooded areas and brush land and
the nearby edges of upland fields. It spend^ most of its HS'e in
underground burrows built much after the fashion of those of the
mole; and indeed they are sometimes mistaken for the burrows of
that animal, although the internal diameter of the mole's burrow
is greater. Loose, moist, and more or less sandy soil is preferred
by this vole in which to construct its complicated series of burrows
and tunnels. Nesting places are constructed both in the burrows
and on the surface of the ground in sheltered places such as brush
piles, fallen timbers, flat stones, and fences.

By means of these runways under the surface of the ground the
voles invade orchards, nurseries, fields and gardens ; and since the
animals remain so much concealed, any injury that may have been
done is not evident for some time.

In discussing the pine mouse (M. p. scalopsoides) , a form closely
allied to the woodland vole, Lantz says: "The number of young
at a birth evidently averages less than is usual in the genus Kicro-
tus, as is shown by the small number of mammag. Observations as
to the number of litters in a season seem to be lacking, but the
rate of reproduction is probably less in the pine mice than in any
other American group of field mice. Blasius says concerning M.
subterraneus of Europe, that 'it produces five or six times a year
three to five young, which are blind for ten days after birth;' and
this statement is probably true, with slight modifications, for all
the species of the group. To compensate for slower multiplication,
their liability to attack by natural enemies is much less, owing to
their underground existence; so that within their range pine mice
are about as abundant as other field mice."18

The food cf the woodland vole consists principally of the roots
of both cultivated and uncultivated plants and trees. Potatoes,
sweet potatoes, beets, carrots, parsnips, and other garden vegetables,
whether growing, stored in pits, or piled up in the fields are eaten
by pine mice. Such damage is often attributed to moles, because of
the tunnels which lead to the point of damage. However, though
moles may cut off the roots of growing plants in their tunneling
operations, they seldom eat the roots for they feed principally upon
insects, earthworms, and other animal food.

"Lantz, D. E., An Economic Study of Field Mice: U. S. Dept. Agr., Biol.
Surv. Bull. No. 31, 20-21, 1907.

FIG. 25. — Pine tree killed by Pine Mice. (From U. S. Department of Agriculture,
Bureau of Biological Survey.)

THE WOODLAND VOLE 95

In discussing- the habits of the pine mousa in Indiana, Quick and
Butler state that, "As a rule the pine mice winter in a last sum-
mer's nest which is a round ball of blue grass blades, from four
to six inches in diameter; the interior is -composed of fine grass
which is nicely bound together with longer blades. The nest is
generally placed beneath a pile of leaves or in an old stump. In
winter collecting single specimens are generally observed occupying
these old nests.

* ' The pine mouse, in winter lives upon the tender roots of young
hickories, the young sprouts of the white clover ( Trifolium repens} ,
the fruit of the red haw (Cratiaegus coccinea L.j and the tuberous
roots of the wild violet ( Viola cucullata Ait. ) . The first of these
he uses for luncheon while excavating his runways. It is never
found stored in his burrows, but as his passages approach these
roots they expand, laying bare a large portion of the root from
which the bark is generally entirely removed. The other products
we find buried, the latter in numerous deposits, some of which
contain a gallon of tubers and extend eighteen inches below the sur-
face of the ground. This latter article evidently forms the bulk
of their winter food."19

So far as the writer is able to determine this is the only form of
pine mouse for which authentic records from the state are at hand.
The localities represented are Thayer, Ottumwa, and Iowa City.
In addition, Vernon Bailey in North American Fauna, No. 17, 1900,
records four specimens from Council Bluffs. See map, page 81.

It would thus seem that this form is distributed throughout
southern Iowa, Iowa City being the most northerly point in the
state from which it has been taken. In states farther to the south
and east of us this form is more abundant. The type locality was
Stilwell (Boston Mountains), Indian Territory.

Economic Importance and Methods of Control. — While the wood-
land vole is apparently not sufficiently common or widely dis-
tributed in the state to be considered of major economic importance,
both its numbers and area of distribution are likely to increase,
with probable resultant damage. It is further probable that some
of the dan: age now attributed to the mole may be the work of 1his
animal, owing to the fact that the latter is not generally known
to the ordinary observer. G-arden crops are sometimes seriously
injured, both the planted seeds and the tender growing plants

19Quick, E. R., and Butler, A. W., The Habits of Some Arvicolinae: Am. Nat.,
XIX, No. 2, 116, 1885.

96 RODENTS OP IOWA

being damaged. In addition, nurseries and orchards are often
attacked and serious loss thereby sustained.

In general, the methods of control recommended for the meadow
mouse will serve for the present form. Wheat, corn, oatmeal, or
the seeds of sunflower, tomato or pumpkin, poisoned with the
strychnia sulphate solution offer the best means of combating this
vole where it has become a pest. In placing the poisoned baits it
is a good plan to distribute them in the underground tunnels
where the voles are most likely to find them and where the lives
of birds and other animals will not be endangered.

Guillotine traps, baited or not, may be set in the underground
tunnels across the runway after a place has been enlarged suffi-
ciently to receive the trap. The opening to the outside should
then be closed. This method is effective for small areas such as
lawns and gardens.

It cannot be too strongly urged that clean and thorough culti-
vation, particularly of nurseries and orchards, the elimination of
brush, dead grass and debris which offers the animals hiding
places, the protection of natural enemies, and the proper and
periodic rotation of crops, are all preventive measures which if
properly carried out will eliminate likelihood of infestation by this
vole. A high state of cultivation materially lessens danger from
attack.

COMMON MUSKRAT. MUSKRAT.

Fiber zibethi-cus zibethicus (Linnaeus).

[Castor] zibethicm Linnaeus, Syst. Nat., XII ed., I, 79, 1766.

Description. — Color above dark chestnut brown, darkest on
head; fur of back and rump mixed with long, blackish brown
hairs ; sides chestnut ; feet dark brown, the claws yellowish brown ;
tail black, sparsely haired, compressed vertically; color below
brownish white, a little lighter on throat and belly; underfur light
grayish ; a small spot on chin and hair of wrist and heel blackish.

Measurements. — Total length, 22.00 inches; tail vertebra, 11.00
inches ; hind foot,. 3.50 inches.

Considerable variation in size and color is exhibited in this
form. The worn pelage is paler and duller than is indicated in the
above description; almost totally black specimens are occasion-
ally met with ; while white or partly white specimens are some-
times captured. Charles B. Cory in discussing this point says:
''About three years ago Mr. "W. S. McCrea of Chicago, called my

THE MUSKRAT 97

attention to a series of seven Muskrat skins from Hay field, Iowa,
all of which were uniformly marked, having a white ring around
the neck and the entire under parts, feet and terminal portion of
the tail white. Such uniform coloration in a series of specimens
was perplexing and suggestive especially as they all came from the
same locality; but later two specimens were received from Indiana,
which were similarly marked, but with the dark parts much paler.
The Field Museum collection contains a pure white example of this
species."20 A specimen collected November 2, 1914, at Sabula,
Iowa, and sent in to the University Taxidermist's laboratory is a
uniform rusty white.

Habits, Distribution, Etc. — The muskrat or musquash, as it is
sometimes called, derives its name from the peculiar musky odor
which is given off by the animal. Its favorite haunts are in ponds,
streams, and overflowed marshes ; and it is found in practically
every part of the state where such situations occur. It lives partly
on land, and possesses also characters which adapt it for living
in the water. The hind feet are slightly webbed, and are formed
so that they may be turned edgewise when moved forward while
the animal is swimming, thus affording the least possible resist-
ance to the water. The long flattened tail acts as a rudder in
swimming; the fur is long and glossy, and the underfur is very
dense, thus making practically a waterproof covering.

Muskrats sometimes wander a considerable distance from water,
particularly in late fall, early spring, and during severe droughts.
The spring migration has been thought to be due to sexual excite-
ment, but no definite reasons can be assigned for the movements
at other times.

While muskrats are, for the most part, abroad at night, they
are often seen in daytime swimming about, lying in the sun along
a bank, or working on their winter houses.

Muskrat houses are composed of grasses, roots and stems of
aquatic plants, rushes, weeds, etc., and the writer has seen entire
houses constructed almost wholly of mud and cornstalks. Appar-
ently the animals utilize the material closest at hand, and that
which, at the same time, will serve the purpose required. These
houses rest upon the bottom of the pond or stream, the domelike
top composed of disarranged materials rising from one and one-

^Cory. Charles B., Mammals of Illinois and Wisconsin : Pub. Field Mus.
Nat. Hist., Zool. Ser., XI, 226, 1912.

7

THE MUSKRAT 99

half to three feet above the water. Cory in describing one of the
houses that he has seen says : " It was built in a marsh on the edge
of a shallow pond; and it was constructed of reeds, weed stalks
and sticks mixed with mud and was somewhat oblong in shape,
although from a distance it appeared to be nearly round. The top
of the rounded dome was three feet high, measured from the sur-
face of the swamp and slightly over four feet where built up from
the side under water. The greatest diameter was 6 feet. The
inside chamber measured about 20x17 inches, the height above the
water being about 14 inches at the highest point, the ceiling being
irregular. The floor of the -chamber was about 7 inches above
the water but slanted downward at one side to a large hole or
passageway leading out under water into the pond. The size of
the houses varies considerably, however, and many are larger."
(I. c., 228-229.) The writer has examined houses similarly con-
structed, though in many cases the materials used have been dif-
ferent. On March 11, 1916, the writer visited Swan lake, a body
of shallow water covering between seventy and eighty acres, eleven
miles northwest of Iowa City. In many places the water, was
frozen to the bottom. Between twenty and thirty muskrat houses
were seen, the largest being three feet high and about six feet in
diameter. All were built of rushes, cornstalks, and debris of dif-
ferent kinds and appeared to be resting upon grass hummocks.

Such houses are used largely for shelter during the winter and
also for storing places for food, but it is seldom that the young
are born in them. Usually a singlo family occupies a house.

High banks are often taken advantage of in the construction of
habitations, and in such cases the entrances to the tunnels are
usually under water. The tunnels extend into the bank below
the level of the water, and often are protected by roots of trees and
shrubs. These tunnels are of varying lengths, and lead up to a
large chamber which in many cases contains1 a nest composed of
dry vegetation. Usually two tunnels lead from the nest to the
water, and in some instances each tunnel has two branches. Bur-
rows seem to be preferred to houses for winter habitation ; but in
shallow ponds and marshes houses become a necessity, and as cold
weather comes en the animals add to the old winter houses, con-
struct new ones, and deepen the channels leading to houses and
burrows. The animals do not hibernate and often make "little
provision for winter. Julius Knepper informs the writer that on

100 RODENTS OP IOWA

one occasion when the horses of a farmer broke through one of
these houses on the edge of a pond near Marengo (Iowa county)
at least a bushel of corn was found within. This may have been
surplus food, which is to be found in some quantity at almost
any time. When the streams and ponds are frozen over, these
animals are able to obtain air in spaces under the ice and fre-
quently air holes are to be found which are kept open through use.

Not much exact and definite information is available concerning
the breeding habits of the muskrat, but the facts so far as known
may be stated in the words' of Lantz : ' ' Normally the animals mate
in March and the first litter is bom in April; a second litter is
due in June or early July, and a third in August or September.
In favorable seasons a fourth or even a fifth litter may be pro-
duced. The period of gestation is possibly no longer than twenty-
one days, as with the common rat and probably with the field
mouse. The young are blind and naked when born but develop
rapidly. Outside of low marshes, muskrats are usually born in
the underground burrows. ' '21

The food of the muskrat consists, for the most part, of vegetable
matter, but occasionally animal food is taken. In winter its staple
articles of diet are the roots of aquatic plants. Carp and other
mud-loving fishes as well as clams also are eaten. Robert Kenni-
cott in speaking of the food habits of this animal says : ' ' The musk-
rat is active in winter, seeking its food under the ice, and carrying
it into its burrow, or house to be eaten. Though roots are some-
times found in a nest in winter, they are only such as have re-
cently been brought in, no considerable stores of food being col-
lected. The food, in winter, appears to .consist of aquatic plants.
In summer, it also feeds upon the leaves of various plants, as
well as upon mussels, (TJmo anodonta and 77. plicatus, etc.), of
which they consume great quantities in some of our rivers. Col-
lecting them at the bottom it carries them in its teeth to a log or
stone, where, sitting upon its haunches and grasping them in the
fore-paws, it opens the shell with the incisors as skillfully as it
could be done with an oyster-knife. In this way, large piles of
shells are collected around stones and logs, by examining which
the conchologist may often find rare species brought from the

«Lantz, D. E., The Muskrat: U. S'. I>ept. Agr., Farmers' Bull. No. 396, 15,
1910.

THE MUSKRAT 101

mud by these animals which have been more successful collectors
than himself."22

While the muskrat does secure some air under the ice, in feeding
it must reach the outer air. Sometimes food is eaten in the houses,
which are not air-tight, while a large portion of the winter food
is eaten near air holes in the ice, which, as has been said before,
are kept open by constant use.

The summer fare of the muskrat includes greater variety and
is made up of roots, stems, leaves and fruit of aquatic plants, sup-
plemented by other fruits and vegetables from adjacent fields.
Garden vegetables are in great favor and onions, cabbage, celery,
carrots, parsnips, beets, peas, etc., are subject to attack with con-
siderable resultant damage. At Chariton, Adel, and Marengo
damage is reported to have been done to green corn, especially in
fields bordering streams. In addition to the mollusks above re-
ferred to, muskrats occasionally feed on the bodies of dead wild
birds, and have been known to attack wounded or trapped in-
dividuals of their own kind. It is said that when food is scarce
they will kill and eat members of their own community.

The food collected by the muskrat in summer is usually eaten
at the edge of the water, in many instances while the captor is
sitting on the end of a log, or on a pile of driftwood.

The muskrat is distributed over most of the state, though dur-
ing the past four or five 'years the numbers have been steadily
on the decrease owing to the extensive trapping and to the draining
of marshes and ponds. In Kossuth, Carroll, Hardin, Calhoun,
Emmett, Winnebago, and other counties of the state in which con-
siderable areas have been drained, the number of these animals
has been materially reduced. In both Emmett and Palo Alto
counties more than one hundred county drainage ditches have been
constructed within the past few years. This extensive system of
drainage has driven out the muskrats but of course many thousands
of acres of exceedingly fertile land have been opened to cultiva-
tion. Outside of the counties above mentioned, considerable num-
bers of the animals have been reported from Dickinson, Franklin,
Lucas, Dallas, Iowa, and Dubuque counties. Bergman Island, in
the Mississippi river near McGregor, supports many houses of
the muskrat. M. X. Geske of McGregor informs the writer that
in the spring of 1914 he counted forty-two houses in one slough

^Kermicott, Robert, Illinois Agr. Kept, for 1856 : U. S. Patent Office Kept.,
106, 1857.

M -JO 4 -J» J i •»«•>*>* * " * ' "i

> j » 5 p'o 3 ? »• 4 « * •* ' •' ** i» '

102 RODENTS OF IOWA

near that place. Muskrat houses are also much in evidence in the
vicinity of Spirit Lake and Estherville. Numerous other ponds
and marshes over the state furnish their quota, but trappers and
collectors everywhere state that the number of these animals has
decreased markedly in the past four or five years.

Economic Importance. — In an economic way the use of musk-
rat fur is of greatest importance. As compared with other furs of
small size muskrats furs are dense, soft, and at the same time possess
excellent wear-resisting qualities. The furriers have worked out
methods of imitating many of the more costly furs with that of the
muskrat, and thus a constant demand for the latter is created. C.
Freedman, furrier at the Edes Robe Tanning Company of Dubuque,
informs the writer that of the smaller mammal skins that come to the
tannery muskrat skins head the list so far as numbers are concerned.
J. A. Spurrell of Wall Lake writes that, ' ' Muskrats were the most
important, [fur-bearing 'animals] because the most abundant. The
skins were worth from eight to ten cents each in 1857 and from 12
to 15 cents each in 1870, when Shelt Tiberghien and two partners
trapped 6250 muskrats from October, 1870, to May, 1871. The
muskrats were called the 'savior of the people', and taxes were paid
from the proceeds of trapping . . . ."

Muskrat fur first came into demand through its use in the mak-
ing of imitation beaver hats. Later, silk and wool having replaced
the beaver, muskrat skins came to be used as an imitation of seal-
skin; and if properly made up they are, indeed, difficult to tell
from the real article, although the wearing qualities are much in-
ferior.

In regard to the trade in muskrat furs Lantz says : ' ' The growth
of the demand for muskrat furs is shown by the records of London
importations and sales. From 1763 to 1800 (thirty-eight years)
the total number of skins imported and sold in that market was
2,831,453, an average of less than 75,000 yearly. During the fifty
years from 1801 to 1850 the total was 20,571,428, or an average of
411,000 yearly. From 1851 to 1890, inclusive, the importations
were 99;893,591, a yearly average of 2,500,000. The average Lon-
don sales in recent years have been ever 4,000,000 per annum, and
the entire output of skins for 1900 was 5,285,000. A large part of
the total collection is sold through London, but in the last few years
an increasing number are dressed and manufactured in America.

Notwithstanding that during the past century and a half nearly
a quarter billion of muskrats have been trapped, the supply has not

THE MUSKRAT 103

greatly diminished. The total output of 1905, as indicated by Lon-
don sales of 5,000,000 skins in 1906, was over 7,000,000. The sale
of these was accompanied by an advance of 40 per cent in prices.
The sales for 1907 showed a further advance of about 25 per cent,
but a falling: off in the offerings of fully 1,500,000 skins. The
London sales for 1908 and 1909 showed still further rise in prices,
which were again advanced in the January and March sales of
1910." (I. c., 24-26.)

The flesh of the muskrat has been used widely as food, particu-
larly by the Indians and by professional hunters and trappers;
while of recent years persons of refined tastes have eaten the flesh,
although with considerable diversity of opinion as to its flavor. The
flesh is fine-grained and dark red in color; but skill and care are
required in skinning the animal that the hair does not come in con-
tact with the flesh, and that the musk glands come away from the
flesh without tearing. The following recipe for cooking muskrat
is copied from Forest and Stream : ' ' Soak the ca-rcass over night in
cold water or let it freeze in the open air. Cut in pieces ready to
serve and place in a pot with a few slices of salt pork. Add water
enough nearly to cover the meat and stew slowly until about dry
— say, for an hour and a half. Pepper and salt to taste while
cooking." (1898, 368.) The musky odor permeates the flesh in
summer, at which season it would scarcely be fit for food.

Muskrats are easily trapped and in winter and early spring
readily take such baits as carrots, sweet apples, parsnips, and tur-
nips. Usually the ordinary No. 1 steel trap is used. Sometimes
the trap is sunk in the trail and embedded partly in the mud and
sand in shallow water. At other times it is set at the opening of
the burrow into a bank, in which case bait is not required. Local
conditions and the ingenuity of the trapper play a considerable part
in successful trapping. Various methods and details of trapping
may be found in Farmers' Bulletin No. 396 of the U. S. Depart-
ment of Agriculture.

While the muskrat does cause some damages in a few places, its
destructive qualities in this state are scarcely sufficient to warrant
drastic control measures. In not many places in Iowa are dams or
dikes employed to hold back large quantities of water, while in
marshy localities the good which the animals do outweighs the
damage. Practically the only incentive to trapping is the value of
the skins; and since their value has, of late years, increased ma-

104 RODENTS OF IOWA

terially, the number of animals may before long be reduced to a
point where the species is in danger of extermination.

The natural enemies, of the muskrat include the mink, and the
larger hawks and owls. Of course floods, droughts and very severe
winters take their toll of muskrat lives, but trapping and the recla-
mation of swamps and marsh lands are mainly responsible for the
great reduction in numbers. The drainage of swamp land is being
carried out extensively in many parts of Iowa, and if a supply of
fur is to be maintained protective laws and private ownership must
seek to maintain the proper equilibrium. Of course it cannot be
denied that the land thus reclaimed is exceedingly valuable from
an agricultural standpoint, but farmers and owners of land on
which suitable muskrat habitats are found should take a part in
the protection of this fur-bearer and see that a few places are re-
served for its use.

In Iowa, the muskrat is protected from April 1 to November 1,
except when found damaging private or public property. It is en-
tirely proper that legal enactment should forbid the destruction
of these animals, especially during the season of reproduction which
the above time is designed to cover. Every one should see that this
law is strictly enforced. Spearing, shooting, and the destruction
of houses should not be tolerated in any community where the ani-
mals are not sufficiently numerous to do material damage ; and if
they are properly protected they will furnish a constant source
of fur for many years.

Where muskrats are exceedingly abundant, especially in the vi-
cinity of canals, drainage ditches and embankments of streams,
methods of control are sometimes required. Trapping is effective
in both summer and winter, but is a slow process. Shooting is ef-
fective for a short time, although a continuation of the practice
causes the animals to become exceedingly wary. Poisoning is an
effective method of destroying them. Powdered strychnia sulphate
mixed with a little powdered sugar and sprinkled over freshly
cut pieces of carrot or apple, has been used with considerable suc-
cess. Sometimes good results can be obtained by inserting crystals
of the strychnia sulphate into baits of apple or carrot. Great care
must be observed in keeping the baits where poultry or live stock
will not reach them.

"When any such protective measures as above suggested are em-
ployed, it is well to confine them to the time when the fur is at its

GREAT PLAINS MUSKRAT 105

best. In this way something is realized in the way of protection,
and at the same time, the skin is thrown upon the market.

Various means of protecting property from damage by muskrats
have met with considerable success, and a few of these may be
mentioned here.

In the construction of dams and bridges the use of concrete
foundations will entirely obviate any likelihood of damage from
muskrats, besides rendering the structures safe from other danger
for many years.

The use of sand or coarse gravel on the surface of embankments
for artificial ponds and the like will prevent muskrats from bur-
rowing, since the sand and gravel fill in the. hole as rapidly as it
is opened.

Gardens and truck patches may be protected from muskrats by
erecting a galvanized wire fence at least three feet in height and
of one and one-half inch mesh entirely around the plot or at least
on the side bordering the stream or pond. The lower edge of the
fence should be set down into the earth at least six inches in order to
prevent the animals from digging beneath it.

GREAT PLAINS MUSKRAT.
Fiber zibethicus cinnamominus Hollister.

Fiber zibethicus cinnamominus Hollister, Proc. Biol. Soc. Wash.,
XXIII, 125, September 2, 1910.

Description. — "Fresh, pelage: Upper parts and sides cinnamon
brown, dorsal areas only slightly darker, with few black hairs.
Nose to forehead and eyes seal brown. Cheeks and underparts
creamy clay color, lighter on neck, throat, and inner sides of legs.
A very small brown spot on chin. Feet drab; nails yellowish. Tail
dark brown. Warn pelage: Varying from wood brown to russet,
depending upon the state of wear or renewal. Specimens in the
short-haired early fall pelage are the darkest, and those in extreme
faded or washed out early summer coat are the lightest. ' ?23

Measurements. — Total length, 19.00 inches; tail vertebrae, 9.20
inches; hind foot, 2.80 inches.

This form averages smaller than the common muskrat, and the
teeth are smaller than in that form. Also paler, the coloration is
with considerable red or reddish in the pelage. "With these ex-

^Hollister, N., A Systematic Synopsis of the Muskrats: N. A. Fauna, No. 32,
30, 1911.

106 RODENTS OP IOWA

ceptions the great plains muskrat -closely resembles the common
muskrat; but its distribution is more to the westward. Hollister
(1. c.), gives the geographical distribution of the present form as
follows : ' ' Great central plains region of western United States and
Canada; from Manitoba south to northern Texas; east to central
Iowa and west to the Eocky Mountains.'/ A single individual is
recorded from Knoxville, Iowa. The writer has not obtained speci-
mens of this muskrat, but collectors and trappers should be on the
lookout for it in western Iowa where the area of intergradation oc-
curs. It is found in the sloughs and streams of the interior plains
region, and its habits are practically the same as those of the com-
mon, muskrat. •

GOSS' LEMMING MOUSE.
Synaptomys cooperi gossii (Merriam).

Synaptomys helaletes gossii Merriam, Proc. Biol. Soc. Wash., X,
60, 1896.

Description. — Summer: General color above rusty brown or red-
dish brown, with which are intermingled black-tipped hairs; a
blackish mark at base of whiskers ; tail short, brownish above, pale
below; color below slaty gray, the hairs tipped with white but the
gray showing through. Winter: Grayer and with less reddish
brown. The young are slaty or grayish brown above, the color vary-
ing with the age.

.Measurements. — Total length, 5.00 inches; tail vertebrae, 0.70
inch ; hind foot, 0.75 inch.

Some little variation in size and color obtains in this form, which,
in our fauna probably most nearly resembles Dyche's harvest mouse.
However, it may be distinguished from that species by the much
shorter tail, the absence of a distinct line along the middle of the
back, and the fact that the upper incisors (front teeth) have the
longitudinal groove on the anterior face much narrower and near
the outer edge. The crowns of the molars (cheek teeth) have trans-
verse loops. These two mice are our only representatives of the
family which have grooved upper incisors, though the extent of the
groove in the two forms differs markedly and in other respe2ts they
are rather widely separated.

Habits, Distribution, Etc. — This is one of our smallest mice
and appears to inhabit grassy fields and hillsides and open places

GOSS' LEMMING MOUSE

107

in the woods. A. H. Howell of the United States Biological Sur-
vey has reported this form present in considerable numbers at
Horseshoe Lake, St. Charles county, Missouri, towards the latter
part of April. Concerning this observation he reports as follows:
"A large colony had occupied a low marshy meadow close to the
Mississippi River. At the time of my visit the water in the river
was very high, and the meadow was overflowed to a depth of
12 to 18 inches. The mice had been driven from their burrows
by the high water, and were hiding as well as they could on tus-
socks and under patches of floating debris. When disturbed they
ran rather freely over the submerged vegetation and swam freely,
but they were easily overtaken. Many had been killed by dogs or
other predatory animals, and I was able to get as many specimens
as I needed by catching them in my hands. The burrows in this
meadow were on the little hillocks, the entrances near the top.
Thus they are probably dry except in times of very high water.

FIG. 27. — Map showing locality records of —

1. Goss' Lemming Mouse (Synaptomys cooperi gosstt).

2. Prairie Harvest Mouse (Reithrodontomys megalotis dychei).

The entrances are perfectly open and not concealed under vege-
tation as is the habit of Synaptomys cooperi in the eastern states.
Well-beaten runways extended out from the burrows and under
the dead vegetation."24

l, A. H., Mammals of the Middle Mississippi Valley : Proc. Biol. Soc.
Wash., XXIII, 30, 1910.

108 RODENTS OP IOWA

The geographical distribution of several of the closely allied
forms of the genus Sywptomys has not yet been definitely worked
out, so that some of the reports which have been made -concerning
the habits of one form may properly be credited to what may prove
to be another. This is probably the form recorded by Osborn
(Proc. la. Acad. Sci., 43, 1887-1889) and in, UA Partial Catalogue
of the Animals of Iowa," (Ames, Iowa, 5, 1891), but in neither
case are definite localities given. T. Van Hyning, (Proc. la.
Acad. Sci., XX, 311, 1913), recorded this form from Fairport,
the record being taken from a single specimen secured by T. Surber
of the U. S. Biological Station, February 16, 1912, on the laboratory
grounds. This mouse has also been recorded from Knoxville. In
the course of this work but one specimen has been received and
that from Logan, Harrison county, at the extreme western border
of the state. Thus, although the recorded specimens have been
taken at widely separated points in the state, the probability is
that Goss's lemming mouse may be found sparingly in practically
every locality.

POCKET GOPHERS.
Family GEOMYID/E.

The family Geomyidae comprises the mammals commonly known
as pocket gophers, the distribution of which is restricted to North
and Central America. The family is best developed in western
United States and Mexico; it does not occur east of the Mississippi
Basin except in the Gulf States where it reaches the Atlantic
States in Florida and Georgia. The members of the family are all
fossorial and live under ground and their structure is modified in
accordance with the needs for a subterranean method of living.

POCKET GOPHER. SHAW'S POCKET GOPHER.
RED GOPHER.

Geomys bursarius bursarius (Shaw).
Mus lursarius Shaw, Trans. Linn. Soc. Lond., V, 227, 1800.

Description. — Upper parts chestnut brown with the concealed
bases of the hairs dark plumbeous ; under parts paler ; feet whitish ;
tail stout, the basal portion with hairs chestnut brown, the apical
portion sparsely covered with white or whitish hairs ; body heavy,
neck very short; fur-lined cheek pouches opening to the exterior;
front feet enlarged, fitted for digging, the claws usually large
and long.

THE POCKET GOPHER 109

Measurements. — Total length, 11.00 inches; tail vertebras, 3.25
inches; hind -foot, 1.50 inches.

Q

FIG. 28. — Faces of Pocket Gophers, showing pouches and incisors. (From IT. '£
Department of Agriculture.)

The pocket gopher shows but little tendency to variation in color
according to season, but the variation in size, due principally to
difference in sex, is quite pronounced. The females are always
smaller than the males, the discrepancy in this species being as
much as an inch in total length, a half inch in length of tail and
from three to five millimeters in length of hind foot. In addition,
differences in cranial characters, aside from the matter of size,
are apparent in the two sexes; the female usually has a broader
and flatter brain case, the zygomatic arches are narrower, the
rostrum and nasals shorter, and the entire skull smoother than is
characteristic of the male.

Habits, Distribution, Etc. — The pocket gopher is of more eco^
nomic importance than all of the other species of the family together
and in Iowa at least is of greater consequence economically than
all our other species of rodents combined. Iowa is fortunate in
that she is furnished with a great deal of exceedingly fertile land,
but unfortunate in that this rodent pest is apparently most at
home in just such rich and densely populated cultivated territory.
A very conservative estimate indicates that the annual loss to agri-
cultural interests in the state of Iowa due to depredation by the
pocket gopher amounts to a half million dollars, This is a sum
which is worthy of consideration and which could be materially
reduced by proper and uniform control measures, which will be
discussed below.

The pocket gopher lives almost entirely in underground tunnels
which it excavates in loose alluvial soils rather than in those which
are hard or clayey. Sandy soils are seldom worked, since burrows
can not be successfully constructed in such loose material; as a

110 RODENTS OF IOWA

result sandy regions are not much troubled with this pest, and
the sandy sections of the state which have been visited report
few of the animals and little damage done. While the pocket
gopher is not strictly nocturnal in its habits, it is most active in
early morning and evening; however, if temperature and weather
conditions are favorable it may work all day and on into the night.
Hot, dry weather affords little incentive for digging. In working
its way through the earth the animal uses the powerful upper in-
cisors in loosening the soil, while the front feet are also used in
digging and in pushing the earth backward beneath the body
where it is carried still further backward by the action of the
hind feet. After a quantity of earth has accumulated behind the
burrower he turns around in the tunnel, places the palms of the
front feet vertically beneath the chin and pushes himself and the
earth along with his hind feet. On arriving at the opening of the
tunnel he forces the earth out to form the so-called gopher "hill."

The writer has seen such mounds of earth six to eight feet in
diameter and a foot or more in height. It is said that on wild
prairie land the pocket gopher frequently throws up mounds
larger than this. The great number of fresh mounds that may
appear in a restricted locality during the course of twenty -four
hours, indicates that considerable distances are traversed.

The burrows are usually about two feet beneath the surface and
often are quite complicated, forming a kind of network of sub-
terranean roads. At intervals of a few feet shafts are run to the
surface for the conveyance of the earth that has been removed in
the construction of the tunnel. It has been estimated that the
burrows of a single animal from one season 's burrowing, if straight-
ened out, would measure a mile in length. In one of the larger
mounds the gopher has its nest where it hoards a supply of food
and rears its young. "Apparently pocket gophers breed but once
a year, usually early in the spring and they produce from two- to
six young in a litter. T. H. Scheffer, of the Kansas State Agri-
cultural College, trapped thirty-four pregnant females from Janu-
ary 31 to May 13. The smallest number of embryos found was 1 ;
the largest 6 ; the average 4.2. While gophers are less prolific
than many other rodents, the seclusion in which they live compen-
sates in great measure for their lack of fecundity, since their ene-
mies have relatively few opportunities to secure them. Except in

THE POCKET GOPHER 111

the mating season and when the female is caring for her young,
gophers seem to live alone. ' '25

Frank C. Pellett of Atlantic has in his collection a young female
pocket gopher taken from the nest of a red-tailed hawk May 18,
1916. The measurements are as follows: Total length, 6.50 inches;
tail vertebra?, 1.80 inches ; hind foot, 0.90 inch.

Pocket gophers have a tendency to roam about somewhat, par-
ticularly in late summer and fall, and at these times numbers of
new mounds are often found in fields some distance away from
the regularly inhabited areas. Even in late autumn and during
the winter the animals, especially the males, wander about more
or less. On October 13, 1913, a live specimen was brought to the
office of the writer by A. 0. Thomas. He had found it running
about on the surface of the ground evidently in migration. This
specimen was kept confined in a wire cage in the office for several
days. It appeared to dislike the light and embraced every oppor-
tunity to escape from it. Apples, potatoes, and the roots and
green stalks of dandelions were fed the animal. • It seemed espe-
cially fond of the green dandelions; and holding a stalk in its
front claws would begin at one end and not stop until the entire
stalk was eaten, when it would be ready for another. The animal
took water from a pipette at times rather greedily and with much
relish.

Charles Miller, living near Decorah, reports having taken
pocket gophers alive in winter from under the snow. The animals
had probably worked out of their burrows and were unable to find
their way back again.

Pocket gophers do not hibernate in the true sense of the word,
but lay up enormous stores for the winter, some of which they
place only a little distance beneath the surface of the earth so
that they are overturned by the plow. Other and more extensive
stores are placed deeper in the soil. The various roots upon
which the animal feeds are cut in short pieces, packed into the
great cheek pouches, and carried away to these caches which usually
contain much more food than the animal can possibly eat. This
great destruction of food materials adds to the extensive damage
done by these animals.

The pocket gopher occurs throughout the state, but is rather
more abundant in the central, northcentral, and eastern counties,

^Lantz, D. E., Pocket Gophers as Enemies of Trees : Yearbook, U. S. Dept.
Agr., 210, 1909.

112

RODENTS OP IOWA

where of course it does most damage. However, not a single county
is blessed by the entire absence of the pest; and, if anything, its
numbers seem to be on the increase in spite of the rather sporadic
efforts made toward its control. In addition to cultivated fields,
the rights of way of railroads form one of the most generally in-
fested areas in most parts of the state.

FIG. 29. — Apricot tree killed by Pocket Gopher.

Agriculture. )

(From U. S. Department of

Food Habits, Economic Importance, and Control Measures. — The
food of the pocket gopher consists, for the most part, of the roots
of various plants, which are usually attacked from below, and with-
out the animal's issuing from the burrow. In early days it fed
on the roots and stems of native plants, but upon the introduction
of cultivated plants by the settlers, it immediately turned its
attention to them, in many cases with disastrous results. In ad-
dition, with the settling of the country, numbers of the natural
enemies of the gophers were destroyed and the soil more or less

THE POCKET GOPHER 113

loosened by cultivation, so that the living conditions of the animal
were improved rather than harmed. As a result, in many places
where strict and cooperative methods of control have not been in
vogue, the animals have increased in numbers and extended their
range.

Among the cultivated plants most attacked by these pests are
clover, alfalfa, timothy, potatoes, and garden vegetables, in addi-
tion to fruit and other trees; while of the uncultivated plants the
roots of wild sunflower, spike-flower, rosin-weed, and other weeds
form the main items.

FIG. 30. — A section of the Apricot tree shown in the preceding view. The injury
was under ground. (From U. S. Department of Agriculture.)

Besides this, gophers do much harm in other ways; they cover
hay lands with earth, thereby preventing close mowing; the
burrows allow the entrance of surface water, and on hilly ground
these form the beginnings of gullies; and burrows in dams often
cause serious breaks. In fields of small grain and corn in the
sho-ck, they sometimes do a good deal of damage by throwing up
mounds of earth under the shocks, thereby burying considerable
grain.

One reason that may be advanced for the extreme destructiveness
of pocket gophers is the fact that since they work beneath the sur-
face their ravages may remain unseen for some time and con-
siderable damage be done before suitable control measures are
thought to be necessary.

8

114

RODENTS OF IOWA

While gophers seldom inhabit forests and hence cause little
injury to forest trees, they do cause considerable damage to orchards,
and nursery stock, apparently not exercising- much choice in the
kind of trees attacked but feeding indiscriminately on their roots.
The animals take not only the bark but the entire root, such roots-
if particularly relished being entirely eaten leaving the trunk
loose in the earth. At Clarion, F. E. Osier reports that pocket
gophers had gnawed the roots of some of the pine trees in the
cemetery there so that the trees leaned very noticeably to one
side. The nursery stock in the Welch Nursery at Shenandoah
also has been damaged in this way.

FIG. 31. — Root of Apple tree gnawed by Pocket Gopher. Root knots prominent.
(From U. S. Department of Agriculture.)

Of course the gopher, in spite of its fossorial and semi-diurnal
habits, has many natural enemies which assist in holding its num-

THE POCKET GOPHER 115

bers in check. Practically all our larger hawks and owls, particu-
larly the barn owl, capture numbers of these rodents outside of
the burrows. Badgers, weasels, and skunks also lay claim to a
share in destroying the pests, skunks and weasels being particu-
larly effective. J. P. Kingsley of Dubuque reports that in that
locality skunks kill many of the gophers. Of the snakes the bull
snake and hog-nosed snake are of first importance. The snakes
and weasels are of special value in that they are able to enter and
traverse the gophers' burrows. It should be unnecessary to state
that all of the above-mentioned enemies of the pocket gopher should
be protected and not needlessly or thoughtlessly killed as is so
often the case. A moment's reflection before striking down one
of these allies of the agriculturist will be productive of much
good.

In the artificial control of any rodent pest, little of permanent
value can be accomplished without mutual cooperation. If a
farmer or nurseryman or fruit-grower in a given locality destroys
the pocket gophers on his own land without others of the com-
munity cooperating in the warfare, his efforts will avail little and
his land will be in constant clanger of being reinfested from
neighboring farms. It cannot be too strongly emphasized here that
united effort on the part of the individuals of a township or
county is the only safe and satisfactory way in which to secure
thorough and permanent immunity from these pests.

That enormous damage is sustained from the ravages of pocket
gophers has long been recognized, and in the attempt to control
the increase and spread of the animals bounties have been offered
in our own state as well as in many others.

Section 2348 of the Supplement to the Code (1907) as amended
by the thirty-fourth General Assembly (1911) relating to the
payment of bounties on pocket gophers provides a uniform, state-
wide bounty of ten cents each and reads as follows :

"Sec. 2348. Bounties.

Sec. 2348-a. Amount of Bounty. There shall be paid from
the general fund of the county a bounty of ten cents for each
pocket gopher caught and killed within the county, provided that
the person entitled to such bounty shall make, as hereinafter pro-
vided, proof of the destruction of such animal within thirty days
after the same was destroyed.

116 RODENTS OP IOWA

Sec. 2348-b. Proofs required. The person catching and killing-
any such animal shall remove and present to the officers, before
whom he makes his proof, both front feet and claws of each ani-
mal for which he claims the bounty, and the person claiming the
bounty shall furnish written proof, under oath, that each animal
for which he claims the bounty was caught and killed in the county
against which he presents the claim for bounty, and the board of
supervisors may require in addition to the above any other and
further proof which it deems necessary and reasonable to show
that each animal for which the bounty is claimed was caught and
killed within the county against which the claim is presented.

Sec. 2348-c. To whom presented. The claws and other proofs
icquired may be presented to the county auditor; and the board of
supervisors of each county may appoint registrars or other officers
in other parts of the county to whom claws of the animal caught
and other proofs of the killing may be presented. ' '

However, as has been indicated before in this paper, the bounty
system as a means of reducing the number of rodent pests is not
only unsatisfactory but very expensive. At best, a bounty is but
a temporary expedient for checking the increase of the animals,
and even if it is made sufficiently large to materially reduce their
numbers in a given locality the time soon comes when it becomes
no longer profitable to secure the animals for bounty. Seldom,
if ever, is a bounty effective in exterminating a noxious animal.
With such an animal as the pocket gopher at least, hope of ex-
termination by offering bounty is entirely out of the question.
Under present conditions it does serve in a measure, to keep down
the numbers of the pests even if extraordinary expense is involved.
If, on the other hand, cooperative effort towards control measures
could be secured along some of the lines that will presently be
suggested, vastly better results could much more economically be
secured, so that the funds now expended in this attempted control
might be diverted into more fruitful channels. North Dakota,
California, and other states have successfully carried out this
plan and with excellent results.

Under the bounty system, as at present carried out, various
methods of payment by the auditors of different counties are em-
ployed, while also the evidence required is somewhat at variance
according to the interest taken by the county officials. In two
of the sixty-two counties visited the people were virtually given

THE POCKET GOPHER

117

to understand by those in authority that a bounty was not paid
on the pocket gopher. In some cases it was found that the full
amount of bounty was paid for a single front foot. In other places
justices of the peace and oificers called registrars are entrusted
with the payment of bounties, these officers making their reports
to the county auditor. Some of the registrars are charged with
dishonesty in the payment of such bounties. In Muscatine county
the board of supervisors decided, in 1911, that the payment of
bounties involved an unnecessary drain upon the county funds;
and accordingly the bounty was removed from all animals upon
which it had been paid and upon which it might be paid except
wolves, and this in spite of the enactment of the General Assembly.
In the course of the preparation of this paper an attempt was-
made to ascertain the amounts paid out in bounty for pocket
gophers in the various counties visited. In all, data from sixty-
two counties of the state have been obtained; and while the re-
sults are not entirely satisfactory, they will give a general idea of
the large amounts expended for the destruction of these pests.
The year 1913 has been chosen simply at random and not with
special reference to any particular point, save that that year seemed
to indicate a fair general average as regards all items concerned.
As a basis for comparison the bounties paid out in the year 1915
in the same counties are added.

REMARKS

.

AM'T PAID

RATE

ON POCKET

COUNTY

(CENTS)

DATE

GOPHERS

Adams

10

1913

$ 640.70

1915

481.10

Allamakee

10

1913

1915

414.70

Appanoose

10

1913

26.00

1915

31.30

Benton

10

1913

505.85

1915

381.55

Bremer

10

1913

165.00

1915

212.60

Buchanan

10

1913

149.50

1915

384.45

Buena Vista

10'

1913

1.90

1915

3.00

Calhoun

10

1913

28.90

1915

13.30

Carroll

10

1913

574.30

1915

564.80

Cerro Gordo

10

1913

1915

136.00

Bounties of gophers, wolves
and crows. Amounts not
kept separate

118

RODENTS OF IOWA

AM'TPAID

RATE

ON POCKET

COUNTY

(CENTS)

DATE

GOPHERS

Cherokee

10

1913

55.00

1915

108.90

Chickasaw

1913

1915

Clarke

10

1913

87.45

1915

239.55

Clay

10'

1913

5.25

1915

.70

Clayton

10

1915

463.50

Crawford

10

1913

2,826.60

1915

3,088.43

Dallas

10

1913

157.90

1915

165.40

Davis

10

1913

9.80

1915

Delaware

10

1913

49«.60

1915

380.40

Des Moines

10

1913

142.50

1915

288.60-

Dickinson

10

1913

30.40

1915

28.80

Dubuque

10

1913

104.70

1915

276.40

Emmet

10

1913

44.00

1915

20.50

Fayette

10

1913

333.70

1915

521.20

Floyd

10

1913

244.60

1915

197.10

Franklin

10

1913

113.00

1915

300.00

Greene

10

1913

114.70

1915

114.40

Hamilton

10

1914

65.70-

1915

24.00

Hancock

10

1913

1915

17.50

Hardin

10

1913

344.72 '

1915

235.80

Harrison

10

1913

3,980.06

1915

11,021.50

Henry

10

1913

42.50

1915

56.80

Iowa

10

1913

848.85

1915

950.00

Jasper

10

1913

2,220.55

1915

2,0'68.70

Jefferson

10

1913

132.00

1915

139.00

Johnson

10

1913

625.00

1915

1,146.59

Jones

10

1913

322.80

1915

301.40

Kossuth

10

1913

30.80

t

1915

41.20

REMARKS

Bounty discontinued in 1910

Total for gophers, wolves and
foxes

THE POCKET GOPHER

Marshall

Mills

Mitchell

Monroe

Montgomery

Muscatine

Osceola
Palo Alto
Plymouth

Polk

Sac

Scott

Union

Wapello

Warren

Wayne

Winnebago

Winneshiek

Woodbury

Wright

AM'T PAID

RATE

ON POCKET

(CENTS)

DATE

GOPHERS

10

1913

12.20

1915

28.70

10

1913

376.90

1915

596.80

10

1913

168.20

1915

519.00

10

1913

5,554.95

1915

42.50

10

1913

9'82.70

1915

725.00

10

1913

1,617.75

1915

2,760.75

10

1913

117.90

1915

87.70

10

1913

45.00

1915

630.70

10

1913

645.00

1915

42.06

1913

1915

10

1913

20.63

1915

13.70

10

1913

1510

1915

3.70

10

1913

891.16

1915

668.54

10

1913

3,493.50

1915

1,456.30

10

1913

232.00

1915

186.25

10

1913

1,103.70

1915

1,246.80

10

1913

333.60

1915

349.85

10

1913

99.60

1915

1,084.20

10

1913

929.90

1915

1,062.50

10

1913

3.60

1915

88.30

10

1913

168.40

1915

103.89

10

1913

2,786.00

1915

2,947.40

10

1913

1,118.15

1915

3,381.40

10

1913

53.30

1915

27.68

REMARKS

Includes bounties on gophers,
wolves, Franklin's spermo-

' phile and striped spermo-
phile

No bounties on gophers since
1911

Includes bounties on gophers,,
wolves and rattlesnakes

Figures include bounties on
gophers, woodchucks, wolves
and foxes

120 RODENTS OP IOWA

In Iowa, control of the pocket gopher is best effected in one of
two ways, trapping or poisoning. If the numbers of the pests
are not great there is little to choose between the two methods, but
if the animals are abundant or distributed over large areas poison-
ing is the cheaper and more efficient method.

Poisoning. — Among the baits that may be successfully used are
parsnip, sweet potato, Irish potato, carrot, beet, celery, and sugar
beet. Any of these may be cut up into small cubes and poisoned
with strychnia sulphate by inserting a few crystals in a slit made
with the point of a knife. Prunes or raisins may be used in place of
the vegetables with as good results.

After the baits have been prepared, the tunnels are located by
using a probe made of a spade or hoe handle shod with a metal
point and with a metal cross-bar for the operator's foot about
fifteen inches above the point. When this probe is withdrawn it
leaves a hole through which the poisoned bait may be dropped
into the runs. The hole may be left open or closed with equally
effective results.

Another method of poisoning gophers which has proved effective
in North Dakota and which is recommended by the United States
Biological Survey, is the placing of cubes of sweet potatoes or
parsnips in their underground burrows. The following simple
directions will prove useful: ''The bait should be cut about an
inch long and a half inch square and washed and drained. From
a pepper box slowly sift % ounce of powdered strychnine (alka-
loid) and 1/10 of this quantity of saccharine (ground together in
a mortar) over about 4 quarts of the dampened baits, stirring to
distribute the poison evenly.

"The runways, which are usually 4 to 8 inches beneath the sur-
face, can be located by means of a probe made of any strong handle
an inch in diameter and 36 inches long. One end should be
bluntly pointed. Into the other end should be fitted a piece of %
inch rod, protruding about 12 inches and bluntly pointed. A foot
rest aids in probing in hard soils. By forcing down this iron
rod near gopher workings, or a foot or two back of fresh mounds,
the open tunnel can be felt as the rod breaks into it. The blunt
end of the instrument is now used to carefully enlarge the hole, a
bait or two is dropped into the run and the probe hole closed.

' ' One soon becomes expert in locating the runs, and a man can
treat 300 to 500 gopher workings in a 'day. Baits need be placed

THE POCKET GOPHER 121

at only two points in each separate system of 20 or 30 mounds
which is usually the home of a single gopher. In fields in which
mounds are so numerous that separate groups cannot be recognized,
baits inserted into the runs at intervals of 50 or 60 feet will prob-
ably kill all the gophers. Small stakes are useful to mark the
locations of baits. In our experience, baits placed fairly in the
open runs have invariably killed the gophers. The method has
found great favor wherever it has been introduced. ' '26

Mr. Gwynri, manager of the Welch Nursery of five hundred
acres at Shenandoah, informs the writer that gophers cause con-
siderable damage, and that a constant warfare in the way of
trapping and poisoning is carried out. Sometimes crystals of
strychnia sulphate are placed in apples or pumpkin seeds which are
buried along with apple and plum seeds planted for future nur-
sery stock.

Trapping. — In places where gophers are not too abundant trap-
ping gives effective results at a minimum expense. Willis Adams,
who does considerable trapping in the vicinity of Chariton, reports
that in 1912 on one farm near this place and working an average
of from two to three hours daily he caught 664 of these pests.
Many other and similar instances have come to hand from time
to time.

The ordinary steel trap (No. 0) is successfully employed in
most places. To set this trap, open up the irain runway of the
gopher with a spade and place the trap so that the top is about
level with the bottom of the tunnel. The chain should be made
fast to a stake or heavy object and the hole closed with boards and
sod in order to exclude light.

There are other and special gopher traps which are used ef-
fectively, and these are often set in the laterals as well as in the
main runways. One of the best of these traps is the Macabee
Gopher Trap, which is made and sold by Z. A. Macabee, Los Gatos,
California. Size No. 3 is best for use against our pocket gopher.
Directions for proper setting accompany the traps, which cost
about $2.00 a dozen.

In setting these traps, after selecting- the freshest mound of
earth, the trapper should dig back with a trowel to the open part
of a lateral and place the trap there. The hole should be covered

^Bell, W. B., and Piper, Stanley E.. Extermination of Ground Squirrels,
Gophers and Prairie Dogs in North Dakota: N. Dak. Agr. Exp. Sta., Circ. 4,
9-10, 1915.

122 RODENTS OF IOWA

to exclude light. In looking- over the mounds of earth that have
been thrown out by the gophers, a slight depression about three
inches in diameter will be noticed ; this indicates the spot to begin
digging.

Although success in trapping may not be met with on the first
few attempts, by a little persistence experience will be gained
and with it better results. Trapping is safe, sure, efficient, and
inexpensive.

JUMPING MICE.
Family ZAPODID/E.

The jumping mice of North America are found only in the
boreal and semi-boreal regions and are nowhere abundant, though
distributed from Hudson Bay to North Carolina and from Alaska
to New Mexico and California. In Iowa, two forms belonging to
-a single genus have been recorded; but they are not sufficiently
common to be considered of economic importance, and in many
places the capture of a specimen arouses considerable local in-
terest.

HUDSON BAY JUMPING MOUSE.

Zapns hudsonius hudsoniiis (Zimmermann).

Dipus hudsmiius Zimmermann, Geog. Gesch. Mensch. u. vierfiiss.
Thiere, II, 358, 1780.

Description. — About the size of the common house mouse, but
with the tail and hind legs markedly longer and more slender;
color above tawny to yellowish brown mixed with darker hairs,
the bases of the hairs plumbeous; a broad dorsal stripe running
from top of head to base of tail, is distinctly darker than the
rest of the upper parts; lower parts and feet white with usually
a distinct yellowish brown line separating the color of the upper
and under parts; tail dark above, whitish below.

Measurements. — Total length, 8.00 inches; tail vertebrae, 5.00
inches; hind foot, 1.20 inches.

In spring and early fall this mouse is noticeably darker in aolor
than in summer and the dark dorsal stripe is in part obliterated.

On account of its elongated tail and hind tegs and its peculiar
method of locomotion when disturbed, this mouse is not likely to
be confused with any of our other forms except the following
subspecies whose distribution in the state is apparently much more
limited.

HUDSON BAY JUMPING MOUSE 123

The Hudson Bay jumping mouse inhabits meadows, shrubby
fields, and thickets bordering woodland. Often it is found in
damp situations along fences. It is most often seen during the
haying season, when it is driven from its hiding place while the
grass is being cut.

The little animal is well named, for when disturbed it moves,
away by a series of leaps or jumps, sometimes remaining motion-
less for a moment between leaps. Ordinarily, the distance tra-
versed in one of these leaps is from six to eight feet, though if
occasion requires this distance can be increased. The animal is.
assisted in leaping by the long tail, which aids it materially in
keeping its balance while in the air.

Jumping mice do not follow beaten paths or runways as is so
often observed among meadow mice, but appear to wander about^
following, to some extent, natural paths and open places.

Toward the latter part of the summer a rounded nest four or
five inches in diameter is constructed. This nest is usually con-
cealed under rocks, bushes, or dried grass and has an entrance hole
at one side. Two individuals, probably a pair, occupy this type
of nest which is used only at the close of the breeding season.

The nest in which the young are brought forth is usually under-
ground, but in some cases in a hollow log or stump. The young
are from three to six in number and are produced in May or
June.

Hibernation apparently occurs in this latitude, beginning at
the time of the first heavy frosts and lasting until spring. "The
animals are generally found singly (sometimes in pairs) in nests
in holes at a depth varying from a few inches to 2 or 3 feet below
the surface. They lie rolled up like a ball with the feet close to-
gether and tail curled about them. If removed from the nest
and subjected to a moderate degree of heat they revive and in the
course of a few hours move about freely, but generally resume
their lethargic state if again exposed to the cold. The pulse and
respiration are very slow."27 Hibernation is also said to take
place in a nest above ground.

The food of the jumping mouse consists, in cultivated areas, of
various grains as well as grass and weed seeds; when it inhabits
the vicinity of wooded places it feeds upon the seeds and nuts of
trees. Sometimes, during the summer, stores of food are laid up

Treble, E. A., North American Fauna, No. 15, 8, 1899.

124 RODENTS OF IOWA

in nests or burrows, but it is probable that the animal does not
use this food since it usually remains quiescent throughout the
cold season.

While the Hudson Bay jumping mouse undoubtedly occurs
throughout the state, it seems to be more common in the prairie
regions. The few definite locality records which have been ob-
tained are as follows — a mounted male specimen (No. 3931) in
the Museum of the State University of Iowa was collected at
Oskaloosa in 1889. The Coe College Museum possesses two mounted
specimens, one collected at Britt, August 20, 1911; the other
bears no data, although B. H. Bailey assured the writer that
it was collected "somewhere" in Iowa. A female specimen of this
species collected near Pomeroy was sent in to the University Taxi-
dermist's Laboratories, March 20, 1916. The animal had been
killed a few days previously. T. C. Stephens of Morningside Col-
lege reports three specimens of this form captured near the Iowa
Lakeside Laboratory in the summer of 1915.

PRAIRIE JUMPING MOUSE.

Zapus kudsonius campestris Preble.

Zapus hudsonius campestris Preble, N. Amer. Fauna, No. 15,
20, 1899.

Description, — Summer: Color above similar to brightly col-
o'red specimens of the preceding form; dorsal area distinct, suf-
fused with ochraceous buff, the sides ochraceous buff ; under parts
and feet white; tail dark gray above, yellowish white below.
Fall: Sides yellowish; the dorsal area almost black, the hairs
tipped with yellowish; upper surface of tail darker than in sum-
mer, and ears darker and bordered with whitish.

Measurements. — Total length, 8.75 inches; tail vertebrae, 5.30
inches; hind foot, 1.10 inches.

This form is very similar to the preceding, differing from, it
mainly in its slightly larger size, its brighter color, and higher
"brain case. The area of inter gradation of the two forms includes
the western part of Iowa, the present form being distributed from
Manitoba south over the Great Plains to Nebraska and west to
Colorado and Wyoming. The prairie jumping mouse is said to
replace the Hudson Bay jumping mouse over the northern and
more elevated portions of the plains west of Minnesota and Iowa
to the base of the Rocky Mountains.

AMERICAN PORCUPINES 125

Definite locality records are not at hand for this form, and ob-
servers and collectors should be on the lookout for specimens so
that the distribution within the state may be definitely worked
out.

AMERICAN PORCUPINES.
Family ERETHIZONTID£.

The American Porcupines are so entirely different from our
other rodents, or, indeed, from any other group of mammals that
they are readily distinguished. In North America the family is
represented by a single genus which contains five forms, while
South and Central America have representatives placed in other
genera. These latter have long tails fitted for grasping while the
North American species have short, blunt and spiny tails. All
the American forms are short-legged, slow-moving, more or less
arboreal animals with a thick body-covering of hairs mixed with
quills. A good deal of superstition has been associated with these
quills. While they are loosely attached to the skin of the animal
and become detached very easily, the animal is not able to "shoot"
them at an adversary as has been so often stated. These quills
are barbed or serrate, so that if they once become embedded in the
skin the efforts of the victim to remove them will usually only
•cause the quill to work into the flesh still mors deeply.

The porcupine inhabits forests and spends most of its time in
trees, from which it obtains a large share of its food. Leaves,
twigs, and bark of maple, basswood, birch, and hemlock are most
preferred; but others are utilized when these are not available.
''In Canada and in the northern portion of Michigan and Wis-
consin they frequent the vicinity of lumber camps and show a
decided fondness for any substance which has a salty flavor, ?uch
as old pork rinds, and they have often been known to gnaw to
pieces old butter firkins and boxes which have contained salty
food of any kind."28

Porcupines are, in the main, nocturnal in habits, though they
occasionally wander forth in the daytime. On the ground their
movements are slow and awkward and they depend for safety
upon the formidable array of sharply pointed and barbed spines.

Chas. B., Mammals of Illinois and Wisconsin : Pub. Field Mus. Nat.
Hist., Zoo}. Ser. XI, 257, 1912.

126 m RODENTS OF IOWA

CANADA PORCUPINE.
Eretliizon dorsatum dorsatum (Linnaeus).

[Hystrix] dorsata Linnaeus, Syst. Nat., X ed., I, 57, 1758.

Description. — Hairs of upper parts mixed with, quills or spines,
the hairs long and entirely or almost concealing the quills on the
lower back, hips, and sides of base of tail; general color above
dark brown to nearly black varied with yellowish white; quills
white at base, the apical third usually black; often a few quills
are entirely black or white; length of quills variable, the longest
from three to four inches ; color beneath brownish black.

Measurements. — Total length, 35.00 inches; tail vertebrae, 5.50
inches; hind foot, 3.50 inches.

The writer has been unable to find any recent records of the
Canada porcupine in Iowa, but it is probable that in earlier days
the species occurred sparingly in the northern and particularly
in the northeastern part of the state. "With, the cutting of the
forests and the settling of the country the animals have practically
disappeared. J. A. Spurrell writes that a porcupine was killed in
Grant City (Sac county) in 1854. T. Van Hyning gives the fol-
lowing record : * * In about 1908 ' some hounds in the same section, r
Allamakee County, 'were badly stuck . up by porcupine quillsr
which had to be pulled from their mouths. Last summer, on French
Creek, Allamakee County, I saw some scrub Hemlocks freshly cut
and gnawed by porcupines.' Geo. H. Berry, Cedar Rapids, Iowa,
April 8, 1913. "29

HARES AND RABBITS.
Family LEPORID&.

The members of this family are widely distributed throughout
the United States but only two forms are at all common in Iowa.
A great number of subspecies and geographical races have been
described and this leads to some confusion in the matter of de-
termining them. Two genera, probably represented in Iowa by
but four species, make the task of separating our forms less ar-
duous. Two of the Iowa forms herein discussed occur very rarely
in the state, so that there is little danger of confusion.

Ordinarily the terms hare and rabbit are used interchangeably
as applying to members of this family; but properly, the word
hare is restricted to those forms which do not live in burrows in

Hyning, T., Proc. la. Acad. Sci., XX, 311, 1913.

HARES AND RABBITS 127

the ground and whose young are born with a well developed coat
of hair and with the eyes open; rabbits, on the other hand, live
in burrows and the young1 are born naked and with the eyes closed.
Of our species, then, the members of the genus Lepus are properly
called hares, while the members of the genus SylvHagm, and other
genera not represented in Iowa, are properly termed rabbits. Com-
mon usage makes it unlikely that the names "jack rabbit," "snow-
shoe rabbit," etc., will be changed to meet this strictly scientific
demand.

It is a well known fact that hares and rabbits are exceedingly
prolific, from four to six young being born at a time and two or
sometimes three litters being produced in a year. In some cases
the animals begin to breed when they are six months old.

While a good deal is known of the habits of the forms occupy-
ing the more populated regions of the United States, much re-
mains to be found out concerning details of life history of even
the well known species. Most species are mainly nocturnal, al-
though the jack rabbit and even the cottontail moves about in
daytime particularly if the weather is cloudy. If food is scarce
both hares and rabbits become more diurnal. "All the species of
Lepus make nestlike 'forms' in sheltered spots, in which they
conceal themselves during the day; although in summer Lepus
campestris [White-tailed jack rabbit] sometimes uses the deserted
holes of other mammals, and in winter burrows into the snow for
protection from the bitter cold, and from the birds and beasts of
prey in the open where it lives.

"Most members of the genus Sylvilagus [this genus contains
the cottontails] use both forms and the deserted burrows of other
mammals, or find shelter under rocks, roots or trees and similar
places. Forms are in common use in summer and in regions which
have a warm winter climate but some species habitually use old
burrows, which they sometimes enlarge. The forms are usually made
under the shelter of dense herbage or under low brushy growths,
and the owner spends the day in them regularly for considerable
periods. The females of many, if not all, species of Sylvilagus
make soft, warm nests of fine grass, leaves and other vegetable
material, lined with hair from their own bodies, and in these
nests the young are born and lie concealed like mice in a nest, while
small and helpless. The nests of cottontails are usually placed
in a bowl-shaped depression in the ground in some sheltered spot,

128 RODENTS OF IOWA

and during the absence of the parent the young are covered and
completely concealed by the material of the nest. At such times
the top of the nest is so like the surrounding surface of the
ground, on which lie dead leaves and grasses, that its presence
can be detected only by chance. ' '30 The young are suckled in the
nest for about three weeks and then are left to shift for them-
selves.

The pelage of hares and rabbits varies in length and thickness
according to climate. Its color responds readily to climatic in-
fluences, also, a fact which accounts in large part for the great
number of recognized geographical races. The pelage is thickest
on the back, and is made up of three sets of hairs which are best
differentiated in this region; a short dense underfur, a longer
coarser coat of hairs, and a still longer coarser and thinner set
of hairs the tips of which overlie the middle coat. Differences in
pelage due to age are to be noted also; the Juvenal pelage is soft
and woolly and is carried until the animal is about half grown
when it gives place to the postjuvenal pelage which is characterized
by the greater development of the middle hairy coat. The post-
juvenal pelage is retained until the animal is almost full grown,,
when the typical adult pelage takes its place. This pelage has
the characteristic coarse hairs of the middle coat accompanying
the long black hairs of the back.

Of our representatives of the family the varying hare and white-
tailed jack rabbit have two annual molts, while the great plains
jack rabbit and the cottontail molt but once during the year. In
the two former the change from the white winter coat to the dark
summer coat is brought about only very gradually. In the two
latter the single molt usually occurs in the late summer or early
fall.

Among American rabbits, variation due to sex is not marked,
though usually very old females are slighth/ larger than males
of the same age. However, individual differences in coloration,
size, length of ears, hind feet, proportion and size of skull are
very marked, thus adding to the difficulty of delimiting closely
related forms. Many forms are also subject to much variation
due to environmental conditions, while other forms seem to be
little affected.

^Nelson, E. W., N. A. Fauna, No. 29, 21-22, 1909.

HARES AND RABBITS 129

Wherever the number of hares and rabbits is excessive in an
agricultural territory they are destructive to fruit trees, nur-
series, grape vines, and crops in general. In Iowa the cottontail
is abundant almost everywhere and is to be considered an enemy
of the fruitgrower and agriculturist. Jack rabbits are much larger
than cottontails, but are not common enough in Iowa to be of much
economic importance. However, on account of their large c-dze,
even if present in small numbers they may cause considerable
damage.

"Rabbits are strict vegetarians, animal food never being eaten
by the adults. They eat all sorts of herbage — leaves, stems, flowers
and seeds of herbaceous plants and grasses, and leaves, buds, bark,
and fruit of woody plants or trees. The most succulent kinds,
such as young shoots, tender garden vegetables, clover, alfalfa, and
fallen ripe fruits are generally preferred ; but when these fail, any
green vegetable growth seems to be acceptable, and the bark of
trees is often resorted to when deep snows cover other supplies or
during long summer droughts."31

Considerable damage by rabbits to trees and nursery stock is
reported from many parts of the state. At Corning, in 1915, it
is reported that most of the nursery sales during that season were
on stock to fill out orchards which had been damaged by rabbits.
Henry Field of the Henry Field Seed Company, Shenandoah, re-
ports more field damage from rabbits than frcm any other rodents.
Mr. Gwynn, manager of the Welch Nursery at Shenandoah, bears
out this statement, and says further that the greatest damage to
nursery stock is done in winter and early spring after heavy snows,
and particularly where drifts have blown up. Here small trees
are girdled and eventually die. Similar reports come from other
places in the state.

Methods of control are considered under the discussion on the
cottontail.

Rabbits are our commonest and most widely distributed game
animals, and during fall and winter are hunted persistently all
over the state. Since their meat is high in food value, this, in part,
makes up for some of their destructive qualities. The skins and
fur are also used in the industries.

31Lantz, D. E., Yearbook, U. S. Dept. Agriculture, 1907, 331.

130 RODENTS OP IOWA

MINNESOTA VARYING HARE. VARYING HARE.
SNOW-SHOE RABBIT.

Lepiis Americanus phaemotus Allen.

Lepus. Americanus pkaeonotus Allen, Bull. Amer. Mus. Nat. Hist.
XII, 11, March 4, 1899.

Description. — Summer: Color above brown and ochraceous bun3
mixed with blackish ; head and middle of back darkest ; upper sur-
face of tail buffy or dusky gray, below white; tops of fore feet
and fore legs tinged with rusty brown; ears bordered with black,
the posterior half whitish with a broad black margin ; inside of
ears grayish; color below white except throat which is brownish;
sometimes color of sides also encroaches on the white. Winter:
Pure white except tips of ears, which are bordered with black
and sometimes with brownish buff in front of them. During spring
and fall irregular markings of brown and white are evident when
the semi-annual change of pelage occurs.

Measurements. — Total length, 18.00 inches; tail vertebras, 1.50
inches; hind foot, 5.25 inches.

Habits, Distribution, Etc. — This is an exceedingly variable form
which prefers wooded regions in which there is dense undergrowth.
The nest is a mass of dried grass lined with fur furnished by the
mother, and is usually concealed in weeds or thickets. From two
to four young are found in a litter ; they are haired and have the
eyes open when born.

The food of this species is made up of grasses, leaves of various
shrubs, clover, and bark of young trees. In some places outside
of the state it causes considerable damage by eating the bark of
fruit trees and grape vines; garden crops also are damaged to
some extent. While the animals usually feed at night they are
often seen during the daytime.

The writer has no definite locality records for the varying hare
in Iowa, but it is included here on the evidence of Pellett and Van
Hyning in their "Annotated Catalogue of the Recent Mammals
of Iowa"32 in which the following information is given: "Mr.
Pellett has seen specimens taken in Iowa. ' '

It is stated also by residents and hunters in northwestern Iowa
that a rabbit different from the jack rabbit occurs there, and it
may be that this is the form to which reference is made. Hunters

32Van Hyning, T.( and Pellett, Frank C., Proc. la. Acad. Sci., XVII, 212, 1910.

(WHITE-TAILED JACK RABBIT 131

and collectors should be on the lookout for this species in order
to definitely affirm the above data, so that specimens and exact
localities may be available for reference.

WHITE-TAILED JACK RABBIT. JACK RABBIT.

Lepus tcnvnsendi campanius Hollister.

Lepus campestris Bachman (nomen praeocc.) Journ. Acad. Nat.
Sci. Philadelphia, VII, part 2, 349-353, 1837.

Lepus townscndi campanius Hollister, Proc. Biol. Soc. Wash.
XXVIII, 70, March 12, 1915.

Description. — Summer: Color above, nearly uniform, varying
from pale yellowish gray to brownish gray, the brownish color of
under-fur showing through; rump similar to rest of back, but a
little paler at sides; entire tail usually white; front and outside
of fore legs and feet dull buff ; anterior border of ears with brown-
ish buff; posterior half of outside of ear white with a broad ter-
minal black patch which includes border of ear at tip ; inside of ear
with a long dusky patch near posterior side; posterior border
whitish or buffy; color below white except under side of neck
which is dull yellowish or grayish buff. Winter: Usually pure
white except irregular areas of reddish buff on tops of fore feet,
nose, and about eyes; front and inside of ears reddish brown; the
underfur reddish brown which shows through when the overlying
white coat is disturbed.

Measurements. — Total length, 24.00 inches; tail vertebrae, 3.50
inches; hind foot, 5.80 inches.

This form resembles somewhat the varying hare, but may be
recognized by its larger size, its long ears tipped with black, and
the much longer tail which is entirely white.

The jack rabbit is our largest representative among the rabbits.
It has two annual molts, but is subject to considerable color varia-
tion, particularly in summer. This is more pronounced on the head
and bcdy, which may vary from dark yellowish buffy with the
underfur of a dusky brown color to paler and brighter buff vary-
ing to grayish buff.

Habits, Distribution, Etc. — This animal has been included in all
the published lists of rodents of the state and has been indicated
as becoming more common and as increasing its distribution to
the east and south, In the Proceedings of the Iowa Academy of

132

RODENTS OF IOWA

Sciences for 1888, Professor Herbert Osborn lists one specimen
taken at Ames. In a later paper, "A Partial Catalogue of the
Animals of Iowa" (1891), he again mentions this form and says,
"Becoming common in some of the northern counties." Professor
C. C. Nutting in his paper, "Report of the Committee on State

FIG. 32. — Map showing locality records of —

1. White-tailed Jack Rabbit (Lepus townsendi campanius) .

2. Great Plains Jack Rabbit (Lepus californicus melanotis) .

Fauna"33 says, "this species is slowly working its way south. Last
year it was reported by Prof. Witter from Muscatine county and
during the past fall a specimen was killed in Johnson county, and
is now in .the State University Museum." Three other specimens
are in the State University Museum; an adult mounted specimen
taken at Iowa City January 19, 1895, and two immature specimens
taken in Emmett county in 1897. M. X. Geske of McGregor in-
forms the writer that this species is coming into that locality
and that the numbers have been on the increase during the past
twelve years. At Creston, Ottumwa, and Chariton the species is
reported as rare. Mr. Gwynn, manager of the Welch Nursery at
Shenandoah, informs me that three specimens were taken at that
place during the winter of 1914. In practically all the northern
counties reports indicate that the jack rabbit is becoming more
abundant and is increasing its distribution to the east and south.
At Decorah it is reported to have come in only during the past

"sproc. la. Acad. Sci. Vol. I, part III, 40, 1892.

GREAT PLAINS JACK RABBIT 133

six or seven years. M. P. Somes informs the writer that he has
taken specimens at Fort Dodge, West Bend, and Ruthven. J. A.
Spurrell of Wall Lake writes as follows: "Jack rabbits or prairie
hares, are becoming more plentiful yearly but the first record I
can find is of one seen in the southern part of the county (Sac)
in 1868 or 1869. One was killed near Lake View in 1870 and it
was five years before the hunter saw another. They did not become
numerous until 1890 to 1900. "34 The writer has seen or had in
his collection specimens from the following additional localities:
Marengo, Wall Lake, Estherville, and Jasper county.

The jack rabbit is scarcely abundant enough in the state to
be considered of particular economic importance, but such con-
trol measures as may be necessary are equally applicable to
Mearns' cottontail and will be found under the discussion of that
species further on in this paper.

GREAT PLAINS JACK RABBIT.

Lepus calif ornicu-s melanotis Mearns.

Lepus melanotis Mearns, Bull. Am. Mus. Nat. Hist., II, No. 4,
297-303, February, 1890.

Description. — Winter: General color above deep ochraceous buff
varying to light ochraceous buff overlaid with blackish ; sides of
body paler; rump patch gray, large and conspicuous and divided
by a broad blackish band extending over upper side of tail ; front
of fore legs and tops of fore feet buffy, a little darker than the
body ; front of hind legs and top of hind feet pure white ; inside
of ears deep buff with a narrow white border on posterior edge,
a black border on tip, and a brownish border posteriorly; color
below white or grayish white.

Measurements. — Total length, 22.00 inches ; tail vertebrae, 3.10
inches; hind foot, 5.10 inches.

The coloration of this form is variable as to individuals, season,
and geographic location but the -characters above will serve to
differentiate it from any of our other forms. Only a single speci-
men of the great plains jack rabbit has thus far been taken in the
state, and Iowa is so far from its supposed normal range that its
appearance here can scarcely be considered more than accidental.
The specimen was taken in the southern part of Johnson county

"History of Sac County, Iowa, by Wm. H. Hart, published by B. F. Bowen
and Co., Indianapolis, Indiana.

134 RODENTS OF IOWA

in the autumn of 1915. E. W. Nelson of the United States
Biological Survey gives the geographical distribution of this Torm
as follows : ' ' Great Plains from east 'Central and northern Texas,
northeastern New Mexico and north through western half of Indian
Territory, all of Oklahoma, extreme southwestern part of Missouri,
all of Kansas and Nebraska, except perhaps extreme eastern parts,
southwestern Dakota, southeastern Wyoming, and all of Colorado
east of Rocky Mountains.'" See also the map on page 132.

MEARNS' COTTONTAIL RABBIT. COTTONTAIL.
GRAY RABBIT.

Sylvilagus floridamts mearnsi (Allen).

Lcpus sylvaticus me&rnsi Allen, Bull. Am. Mus. Nat. Hist., N. Y.
VI, 171, 1894 (footnote).

Description. — Color above pale yellowish brown, with an over-
lying wash of blackish; sides cf head and body paler; rump dull
gray, forming a rather distinct rump patch ; nape tinged with
rufous brown or rusty brown; tail above dull brownish tinged

FIG. 33. — Young Cottontail at about the time of leaving nest. Photo from life

by Prank C. Pellett.

"'Nelson, "S, W., N. A. Fauna, No. 29, 146, 1909,

THE COTTONTAIL

135

with grayish ; under surface white ; upper surface of legs pale
brown; outside of ears buffy grayish, plainly bordered with black
along front margin and at tip ; inside of ears dull gray ; color
below white; under side of neck dark buffy.

Measurements. — Total length, 17.80 inches; tail vertebrae, 2.45
inches; hind foot, 4.00 inches.

This, like most other members of the family, is a variable form
but is not likely to be confused with any of our other species.

Habits, Distribution, Etc. — The cottontail is our commonest spe-
cies of rabbit and is usually found in thieketed woods and in open
country supporting underbrush. It is also fond of frequenting
gardens, particularly if there are bunches of weeds and bushes
or tufts of grass under which it may construct its "forms." It
does not make burrows, but often occupies holes in the ground
or in hollow logs. The cottontail is timid and gentle and when

FIG. 34. — Cottontail Rabbit in its "Form." (From U. S. Department of Agri-
culture, Bureau of Biological Survey.)

caught does not attempt to bite but often utters a shrill squeal.
Although it is practically defenseless, the senses of hearing, sight,
and smell are strongly developed as are those senses in other

136 RODENTS OF IOWA

members of the family. When feeding undisturbed, cottontails
move about leisurely by short hops ; but when frightened they make
good use of their long, muscular hind legs, and progress very rap-
idly by a succession of leaps of from eight to ten feet. They are
able to maintain a sharp pace for a considerable time.

The cottontail is common or even abundant in practically all
parts of the state, and specimens are at hand from or have been
seen in almost every locality visited.

FIG. 35. — Apple tree killed by Rabbits. (From U. S. Department of Agriculture,
Bureau of Biological Survey.)

Food Habits, Economic Importance, and Control Measures. — The
food of the cottontail, in, general, is included in the foregoing dis-
cussion of the family. In summer, grass, leaves of shrubs, bark
of trees, clover, alfalfa, and corn ; in fall, apples, cabbages, tur-
nips, and other garden vegetables; and in winter, the twigs and
bark of woody plants and trees form its principal articles of diet.
It is especially fond of peas and cabbages and market gardens are
in numerous instances damaged considerably. Trees and shrubs
are injured either by the bark's being eaten or by the tips of

THE COTTONTAIL

137

branches and twigs being cut off. Some of the damage done by
field mice is often attributed to rabbits; the tooth marks of the
former, however, are small, and they usually begin their work
at or below the surface of the ground ; rabbits, also, usually tear
off the bark in strips. In addition, in many cases nurseries of
young fruit and ornamental trees and shrubs are severely damaged
by rabbits.

Such a prolific and destructive animal must be held in check
in some way, else it so increases as to be3ome a menace to agricul-
ture. Among the natural enemies of the cottontail which are espe-
cially effective in reducing their numbers are the hawks, owls,
and carnivorous mammals. Of the former may be mentioned the
marsh hawk, Cooper's hawk, Swainson's hawk, red-tailed hawk,
rough-legged hawk, long-eared owl, short-eared owl, barred owl,
and great horned owl. At least some of these birds are found in
every locality in the state; and as practically all of them feed
upon other noxious animals, they should be protected and not wan-
tonly destroyed. Of the mammals, wolves, foxes, minks, weasels,
and domestic dogs and oats are effective in keeping down the num-
bers of rabbits.

FIG. 37. — Details of a Wellhouse Rabbit trap. (From U. S. Department o\
Agriculture, Bureau of Biological Survey.)

In Iowa, at least, hunting has been the most effective method
for holding in check the number of rabbits and of the methods of
hunting, shooting seems to be generally chosen. The manager of
the Welch Nursery at Shenandoah informs the writer that, with
them, hunting is the most successful method of combating the cot-
ion tail and the proprietors of the nursery employ hunters and

138 RODENTS OF IOWA

furnish guns and ammunition during practically all the winter
months. Ferreting is practiced on a small scale in some localities,
as is also the use of the beagle, in which case the gun is depended
upon to kill the game.

Rabbits are easily trapped, and this method of destruction is
quite widely practiced in the state. Although slow it is practicable
in gardens, orchards, and nurseries. The old fashioned box trap
with a figure-4 trigger, the details of whose construction are known
to almost every boy, is most often employed.

Another form of trap known as the "Wellhouse" trap and
used very successfully in Kansas is easily -constructed. "The trap
is a box made of 6-inch fencing beards, old ones being preferred.
The box is about 21 inches long, closed at the back by a board,
but in front by a wire door only. The door is hung from the top
and swings inward. A cleat at the bottom prevents its opening
outward. The trap is set and the wire door is kept open by a wire
trigger-rod, held in place by two staples fastened to the top of the
box. This trigger is bent downward near the rear of the trap and
formed into a loop or a figure eight. As the rabbit enters the trap
and crowds into the back part, it pushes upon the loop, moves the
trigger wire backward, and releases the wire door. This falls
and makes the rabbit a prisoner. Bait may be used, but is not
necessary, since the cottontail is constantly looking for dark places
to hide from enemies or cold winds.

"The materials needed for making a Wellhouse trap are: Four
boards 1 by 6, 21 inches long; one piece 1 by C, 8 inches long for
the back ; a short cleat for the door stop ; 281/£ inches of wire to
serve for the door ; 22 inches of wire for the trigger ; four small
staples for hanging the door and trigger; and nails."36

One of the most effective and, at the same time one of the
cheapest methods of destroying rabbits is by means of poison, the
most favorable time for its use being in/ the winter. Crystals of
strychnia sulphate are placed in apples or ripe prunes, which are
then scattered along the paths or runways frequented by the rab-
bits. The poisoned baits may be placed on the ground or raised
on a short stick. This plan has proved effective in some of the
nurseries of the state. Another method of poisoning rabbits in
winter is to cut small twigs from apple trees and dip them into
a solution of strychnin and sugar, after which they are scattered

z. £, E-, TearbQQk, TJ. g. Pept Agriculture, 1907, 337-338,

THE COTTONTAIL 139

along paths and runways. With this method there is little danger
of poisoning other animals than rabbits and field mice. Whenever
poisoned baits of any kind are used, great precautions should be
taken that human beings and farm animals are not accidentally
poisoned. In addition, the carcasses of poisoned rabbits should be
buried whenever found.

If rabbits are abundant and the area to be protected is not great,
such as a small block of nursery trees or a garden, a woven wire
fence from 30 to 36 inches in height and of sufficiently fine mesh
to keep out the animals may be employed. Sometimes the lower
edge is turned outward and covered with soil, or a barbed wire is
stretched along the ground beneath it to prevent the rabbits Crom
digging under it. This method of protection is practiced in Iowa
and is effective unless the snow drifts badly thereby allowing the
animals to walk over the fences.

Many devices and washes have been used and recommended for
the protection of trees. One of the most effective and one which
is applicable to both rabbits and field mice may be mentioned here.
The formula for this wash, in the same proportions as given by
Lantz (1. c. 340), is as follows:

Unslaked lime 4 pounds

Flowers of sulphur 3 pounds

Water to make 9 to 10 gallons

Mr. Lantz says of this wash: "A little salt may be added to in-
crease the adhesive property of the mixture. The lime, sulphur
and about a third of the water are boiled together for at least

one hour and the full quantity of water is then added For

protection from mice and rabbits the trunks only require treat-
ment and the wash may be applied with a brush. One application
in November should last the entire winter."

Various- mechanical means for protecting young fruit trees have
been tried out, of which three or four of the most dependable will
be mentioned. If protection from rabbits only is required, a
woven wire netting, twenty-four to thirty inches wide and with
a one-inch mesh, is recommended. Cut the wire into one-foot
lengths and roll each section about the trunk of a free, fastening
the ends by bending the wires together; the wire should not be
in contact with the trunk. This makes a permanent and effective
protection. If the trees are to be protected from field mice also
a netting of closer mesh must be used, wire window screen netting
being excellent for this purpose.

140 RODENTS OF IOWA

Cloth wrappings well fastened offer effective protection, but
should be removed in spring as they afford hiding places for de-
structive insects. Cornstalks are sometimes used for the protection
of trees. They are cut into two foot lengths, split, and tied with
the flat side towards the tree so that the trunk is completely sur-
rounded. Various forms of wood protectors also are employed;
and if pressed into the earth around the base. of the tree, offer
protection from field mice also. They should, however, be re-
moved in spring as they furnish retreats for hibernating insects.

Clean cultivation, the removal of brush, grass heaps, etc., will
also be of considerable benefit, for this lessens the number of good
hiding places.

CHARACTERS OF THE RODENTS 141

PART II.
DIAGNOSTIC CHARACTERS OF THE RODENTS.

In this more technical part of the bulletin is included a diag-
nosis of the order Rodentia, following which are keys and brief
diagnostic descriptions of the suborders, families, and genera in
regular sequence. Tables are included also lor use in delimiting
the species and subspecies of rodents known to occur, or to have
occurred in the state, these tables being intended only for the Iowa
representatives of the group. The page number following the
specific name in the keys, refers to the general discussion of the
species in part I.

Order RODENTIA. Gnawing Animals.

Incisor teeth long, strong, growing from persistent pulps, the
enamel chiefly or wholly on the anterior face, producing a chisel-
like -cutting edge ; canine teeth absent ; molar teeth few, and sep-
arated from the incisors by a wide diastema; toes usually with
nail-like claws ; feet usually plantigrade ; cascum very large ; brain
smooth or with few furrows, the cerebrum not overlapping the
cerebellum; articular surface for lower jaw elongated antero-poster-
iorly ; malar bone in middle of zygomatic arch ; size small to moder-
ate; furred, some forms spined.

Key to Suborders of Rodeijtia.

Never more than two upper incisors ; enamel confined to anterior
faces of these teeth Simplicidentata

Upper incisors four in number, the second pair very small and
situated immediately behind the first; enamel extending partly on
sides of these teeth Duplicidentata

Suborder Simplicidentata.

One pair upper incisors, the enamel confined to anterior faces;
incisive foramina of palate moderate and distinct; bony palate
extensive ; tibia and fibula distinct, the latter not articulating with
the calcaneum.

142 RODENTS OF IOWA

Key to the Families of Simplicidentata.

1. Body bearing sharp, stiff spines partly concealed by hair

(6) Erethizontidae

Body without spines 2

2. Tail broad, flattened dorso-ventrally (2) Castoridae

Tail not broad and flattened dorso-ventrally .' 3

3. Hind legs and feet markedly elongate; tail very long

(5) Zapodidae

Hind legs, feet and tail moderate, not greatly elongate 4

4. Tail thickly haired and more or less bushy. ..... (1) SciuridaB

Tail naked or closely or sparsely haired, not bushy 5

5. External cheek pouches present; claws of front feet

much elongated (4) Geomyidae

External cheek pouches wanting ; claws of front feet not
greatly elongated (3) Muridae

Family SCIURID£.
SQUIRRELS, WOODCHUCKS, SPERMOPHILES, ETC.

Tail cylindrical, bushy, with long hairs, never covered with
scales; postorbital processes distinct; molar teeth rooted, tuber-
culate ; first upper premolar small, and sometimes wanting ; cheek
pouches, when present, opening inside the mouth.

Key to the Genera of SciuridaB.

1. Front and hind legs joined together by a lateral ex-
pansion of skin from sides of body. Glaucomys

Front and hind limbs not joined together by a lateral ex-
pansion of skin from sides of body 2

2.. Length of body from nose to root of tail over 14.00

inches Marmota

Length of body" without tail less than 14.00 inches 3

3. Tail long and bushy; cheek pouches absent or opening

inside the mouth Scinrus

Tail moderate or short; cheek pouches present, external 4

4. Back with two pale stripes and several black ones; no

rows of pale round spots '. Tamias

Back with or without stripes; if stripes are present, a
series of pale, round spots along the middle of each dark
stripe 5

SUBFAMILY SCIURIN^E 143

5. Thumb large, nail well developed; body thickset; no

stripes on back Cynomys

Thumb small, nail rudimentary; body rather slender;

color pattern .variable Citellus

Subfamily PTEROMYIN>E.

Genus Glaucomys Thomas.

Fur soft and thick ; legs connected by a loose skin extending out
from the sides of the body ; tail depressed, thickly haired at sides ;
ears large; eyes large; postorbital processes narrow, spinelike;
rostrum short.

Dental formula— I. 1/1: Pm. 2/1; M. 3/3=22.

A single form occurs in Iowa.

Southern Flying Squirrel.

Glaucomys volans volans. p. 17

Subfamily SCIURIN/E.

•
Genus Sciurus Linnaeus.

Tail long, broad, bushy especially at sides; eyes and ears large;
five claws on front feet, the claw on thumb small, and scarcely
evident; anterior upper premolar small or wanting; postorbital
processes well developed, directed downward and backward; in-
fraorbital foramen slitlike and confined to lower portion of
maxillary.

Dental formula— I, 1/1 ; Pm. 2/1 or 1/1 ; M. 3/3=22 or 20.
Key to Species of Sciurus.

1. General color gray; color below white or whitish.

Northern Gray Squirrel.
Sciurus carolinensis leucotis. p. 22

General color not gray; color below sometimes whitish
tinged with rusty 2

2. Total length 21.00 to 23.00 inches; general color more
or less tawny brown.

Western Fox Squirrel.
Sciurus niger rufiventer. p. 19

Total length 12.00 to 15.50 inches; general color reddish

brown. Red Squirrel.

Sciurus hudsonicus loquax. p. 25

144 RODENTS OF IOWA

Genus Tamias Illiger.

Back conspicuously striped ; tail short, not bushy ; cheek pouches
large; postorbital processes slender, pointed, directed obliquely
backward and downward; infraorbital foramen oval, confined to
lower part of maxilla.

Dental formula— I, 1/1 ; Pm. 1/1. M. 3/3=20.
Key to Species of Tamias.

Back with two whitish stripes, and five black ones; chestnut
rufous on rump; total length, about 9.60 inches.

Chipmunk.
Tamias striatus striatus, p. 26

Similar to above, but grayer and larger ; rump -cinnamon brown;
total length, about 10.25 inches.

Gray Chipmunk.
Tarsias strMus griseus. p. 27

Subfamily MARMOTIN/E.
Genus Citellus Oken.

Body rather slender; tail variable in length, but not bushy;
ears variable, but not tufted; cheek pouches large; front feet
with four well developed toes, the thumb rudimentary; hind feet
with five toes; postorbital processes slender and spinelike; ante-
orbital foramen circular, a tubercle on lower outer edge; two
upper premolars, the first much smaller than the second.

Dental formula— I. 1/1; Pm. 2/1; M. 3/3—22.
Key to Species of Citellus.

Color grayish brown, not striped; total length, about 15.00
inches.

Franklin's Spermophile.

Citellus franklini. p. 36

Back with seven yellowish white lines, which alternate with
six rows of rounded, yellowish white spots in a brown background ;
total length, 10.50 inches.

Thirteen-lined Spermophile.
Citellus tridecemlineatus tridecemlineatus. p. 29

FAMILY CASTORID^] 145

Genus Cynomys Rafmesque.

Body unmarked, not sharply bicolor; pelage short; tail short,
flat; ears rudimentary; cheek pouches shallow; wrist and heel
heavily furred; feet with; claws on all five toes, the thumb large,
and the nail well developed; postorbital processes strong1, de-
curved: infraorbital foramen large, subtriangular ; molar series
divergent anteriorly, the teeth large, and expanded laterally;
first premolar large.

Dental fcrmula^-l. 1/1 ; Pm. 2/1 ; M. 3/3=22.

A single form occurs in Iowa.

Black-tailed Prairie-dog.
Cynomys ludovicianus ludovicianus. p. 40

Genus Marmcta Blumenbach.

Size large, legs short ; tail short, thickly haired ; front feet with
four well developed tees, the thumb rudimentary and with a flat
nail; hind feet with five tees; skull heavy, flattened above; post-
orbital processes broad at base, stout, decurved, at right angles to
long axis of skull ; first premclar nearly as large as second ; molar
series with two transverse grooves across their crowns; nearly
parallel. j

Dental formula^-I. 1/1 ; Pm. 2/1 ; M. 3/3=22.

A single form occurs in Iowa.

Southern Woodchuck.
Marmota monax monax. p. 45

Family CASTORID/E.
BEAVERS.

Tail broad and flattened, hairless and covered with scales; five
toes on both fore and hind feet, the latter broadly webbed ; second
toe of hind foot with double claw; skull stout, without postorhital
processes; infraorbital foramen nearly concealed by a large, almost
vertical ridge on the maxilla; incisors large, powerful, the lower
much longer than the upper, and the anterior surface deep orange-
red in color; molars single-rooted with re-entering enamel folds,
and decreasing in size posteriorly; molar series converging ante-
riorly; palate arched and contracted anteriorly.
10

146 RODENTS OF IOWA

Genus Castor Linnaeus.

In addition to the family characters above mentioned, the fol-
lowing may be included here, since but a single genus is recog-
nized: Upper molars subequal, with one inner a,nd tw'o outer
enamel folds; molars with dentinal pulp persisting until late in
life; teeth of molar series not parallel but converging anteriorly.

Dental formula— I. 1/1 ; Pm. 1/1.; M. 3/3—20.

A single form has occurred in Iowa.

Beaver.
Castor canadensis canadensis. p. 50

Family MURID/E.
BATS AND MICE.

Lower incisors compressed; premolars wanting; molars never
more than three in each jaw, with or without roots, tuberculate
or with enamel folds; frontals contracted; infraorbital foramen
wider above than below; jugal splintlike; postorbital processes
wanting; tibia and fibula anchylosed below.

Key to the Genera of Muridae.

1. Total length 10.00 inches or over 6

Total length less than 10.00 inches 2

2. Front of upper incisors with longitudinal groove 3

Front of upper incisors without longitudinal groove 4

3. Superior incisors with a deep longitudinal groove nearly

as broad as the face of the tooth Reithrodontomys

Superior incisors longitudinally grooved on outer edges

only Syna-ptomys

4. Tail short ; length of tail vertebrae usually not over 2.00

inches ; form short ; ears short Microtus

Tail longer ; length of tail vertebrae over 2.00 inches ; form
longer; ears longer. ..'..- 5

5. Molars of upper jaw with tubercles on crowns extending

in two longitudinal rows Per omy sous

Molars of upper jaw with tubercles on crowns extending

in three longitudinal rows Mus

6. Tail rounded Eattus

Tail laterally compressed Fiber

SUBFAMILY MURINJE 147

Subfamily MURIWE.

Genus Mus Linnasus.

Three molars in upper jaw, the tubercles on the crowns arranged
in three longitudinal rows ; crown of anterior molar larger than
both the others combined; third molar very small; fore feet with
four developed toes and a rudimentary thumb with a short nail;
five developed toes on hind feet; ears large, prominent; nose
acute ; tail long, usually nearly naked and scaly.

Dental formula— I. 1/1 ; M. 3/3=16.

A single form occurs in Iowa and the United States.

House Mouse.
Mus musculus. p. 52
Genus Rattus G. Fisher.

Premolars wanting; upper molars with tubercles on. crowns ar-
ranged in three longitudinal rows; "molars slightly graduated, in
size from first to third, the anterior tooth not tending to assume
the main function of the tooth row, the posterior tooth not tending
to disappear, enamel folding of upper molars directly referable
to a simple 9-cusped pattern and its reductions, the outer margins
of M1 and M2 never with more than 3 cusps, the inner margin
of same teeth never with more than 2 cusps, M1 usually with 5
roots, its first lamina not distorted by the backward displacement
of the antero-internal tubercle ; upper incisor moderately com-
pressed, set at such an angle that its outer side is worn smoothly
away by action of lower teeth. ' '37

Dental} formula^-I. 1/1 ; M. 3/3=16.
Key to Species of Rattus.

Ears moderate; length of tail usually less than length of head
and body; color grayish brown ?bove, white below; hind foot, 38
to 46 mm.

Brown Rat.
Rattus norvegicus. p. 54

Ears larger, broader; tail longer than head and body; entire
pelage dusky in color; hind foot, 33 to 37 mm. (Probably not now
occurring within our limits.)

Black Rat.
Rattus rattus. p. 68

"Miller, G. S., Proc. Biol. Soc. W&sh., XXIII, 58, 1910.

148 RODENTS OF IOWA

Subfamily CRICETIN/E.
Genus Peromyscus Gloger.

Unworn molars with a double series of conical tubercles which
become worn by abrasion, resulting in a constantly changing1
pattern; molar series short, narrow, the teeth decreasing in size
from front to back; size moderate, face long, nose pointed; ears
thin, rounded; feet small, the palms naked, the soles of hind feet
with five or six tubercles; tail slender, haired, at least two inches
long ; belly white or whitish ; pelage soft, often glossy.

Dental formula— I. 1/1 ; M. 3/3-— 16,
Key to Species of Peromyscus.

Tail vertebrae less than 2.75 inches; tail sharply bicolor; gen-
eral color brown mixed with black ; total length, 5.50 to 6.50 inches.

Prairie White-footed Mouse.
Peromyscus maniculatus bairdi. p. 73

Tail vertebras more than 2.75 inches; tail not sharply bicolor;
general color brown, darker along middle of back; total length,
about 7.00 inches.

Northern White-footed Mouse.

Peromyscus leucopus noveboracensis. p. 69
Genus Reithrodontomys Giglioli.

Body slender; size very small; tail long, more than one-third
total length, scaly, slender, and sparsely haired; ears prominent;
soles of feet with six tubercles; no cheek pouches; upper incisors
with a deep longitudinal groove nearly as broad as the face of
the tooth ; lower incisors simple ; molars with the tubercles ar-
ranged in two longitudinal series; first upper molar with five
principal tubercles; posterior border of palate square, terminating
opposite posterior border of last molars ; outer wall of anteorbital
foramen a broad thin plate.

Dental formula^-L 1/1 ; M. 3/3--—16.

A single form occurs in Iowa.

Prairie Harvest Mouse.
Reithrodontomys megalotis dychei. p. 76

Subfamily MICROTIN/E.

Genus Microtus Schrank.

Form short, thickset; tail, legs and muzzle short; ears short,
buried in the fur; upper incisors not grooved; root of lower in-

GENUS FIBER 149

cisor extending1 back to third molar, displacing the base of that
tooth ; molars not rooted, the crowns with irregular triangles or
loops ; soles of feet with four to LUX tubercles.

Dental formula— I. 1/1; M. 3/3=16.
Key to Species of Microtus.

1. Total length more than 5.50 inches; tail vertebrae more

than 1.10 inches long 2

Total length less than 5.50 inches; tail vertebrae 1.00 inch
or less long; upper parts dull chestnut; under parts
plumbeous tinged with cinnamon rufous ; mammae 4

Woodland Vole.
Microtus pinetorwm nemoralis. p. 91

2. Tail usually less than 1.60 inches long; five tubercles on
soles of feet ; upper parts mixed light and dark brown ;
under parts buffy gray, or pale brownish gray ; mammae
6

Prairie Meadow Mouse.
Microtus ochrogaster ochrogaster. p. 87

Tail usually more than 1.60 inches long; six tubercles on
soles of feet; upper parts brownish, but without the
' ' grizzled ' ' appearance of M . o. ochrogaster; under parts
grayish white, sometimes tinged with brown ; mammas 8.

Meadow Mouse.
Microtus pennsylv (miicus pennsylvamcus. p. 78

Genus Fiber Cuvier.

Size large, form stout; legs short, feet large and modified for
swimming; toes of hind feet partly webbed; tail long, verti-
cally compressed, covered by thin scales, and scantily haired; ex-
ternal ears small, almost hidden in the fur, which is dense and
waterproof; a series of long, glossy overlying hairs intermingled
with the shorter pelage; well developed perineal glands secreting
a strong odor; mammaa 6; five tubercles on soles of feet; upper
incisors without grooves; molars rooted; auditory bullae large, the
edges protruding.

150 RODENTS OF IOWA

Dental formula,— I. 1/1; M. 3/3=16.
Key to Subspecies of Fiber.

Size large; hind foot averaging over 80 mm.; color dark brown.

Common Muskrat.
Filter zibethicus zibethicus. p. 96

Size smaller ; hind foot less than 80 mm. ; color reddish or pale
brown. :j « ||fj ]

Great Plains Muskrat.
Fiber zibethicus cinnamominus. p. 105

Genus Synaptomys Baird.

Front of upper incisors with a distinct longitudinal groove near
outer edges; root of lower incisor ending abruptly opposite last
lower molar ; crowns of molars with transverse loops ; teeth of
molar series strongly convergent anteriorly, the individual teeth
large ; ears equal to or longer than the fur ; tail equal to or longer
than hind foot ; pelage dense and soft.

Dental formula^-!. 1/1 ; M. 3/3=16.

A single form occurs in Iowa.

Goss ' Lemming Mouse.
Synaptomys cooperi gossii. p. 106

Family GEOMYID£.
POCKET GOPHERS.

Form short, heavy; large, external, fur-lined cheek pouches
opening outside the mouth; feet fossorial, the front pair being
particularly well developed; eyes and ears minute; tail thick,
fleshy, usually hairless; molars rootless.

Genus Geomys Rafinesque.

Upper incisors furnished with two longitudinal grooves, a broad,
deep one along the middle, and a smaller and narrower one along
the inner edge; crowns of teeth of molar series with transverse
enamel loops, a single loop on each molar, two loops on the pre-
molar ; infraorbital foramen confined to lower portion of maxilla ;
auditory meatus tubular, elongated.

Dental formula^-I. 1/1 ; Pm. 1/1 ; M. 3/3=20.

A single form occurs in Iowa.

Pocket Gopher.
Geomys bursarius bursarius. p. 108

FAMILY KRETHIZONTID^E 151

Family ZAPODIDJE.
JUMPING MICE.

Body enlarged posteriorly; hind legs and tail much, elongated,
the latter greatly exceeding the trunk in length, very slender and
scantily haired; fore legs short; upper incisors compressed, and
sulcate; molars rooted; ante-orbital foramen large, with an addi-
tional notch or foramen at its lower portion.

Subfamily ZAPODIN/E.

Genus Zapus Coues.

Internal cheek pouches present, small; first digit of fore foot
rudimentary, nail flat and blunt; hind foot with five toes, each
with separate metatarsal ; anteorbital foramen large, obliquely oval ;
upper incisors short, stout, grooved ; orange brown in color ; upper
premolar present, small; crowns of molars with complex enamel
folds; pelage coarse.

Dental formula^-I. 1/1; Pm. 1/0; M. 3/3—18.
Key to Subspecies of Zapus.

Color above tawny to yellowish brown ; total length, 8.00 inches.

Hudson Bay Jumping Mouse.
Zapus hudsonius hudsonius. p. 122

Color above paler; total length, 8.75 inches.

Prairie Jumping Mouse.
Zapus hudsonius campestris. p. 124

Family ERETHIZONTIME.
AMERICAN PORCUPINES.

Form short, stout; body more or less covered with sharp, stiff
quills which are loosely attached to the skin; molars more or less
completely rooted ; facial portion of skull short, the jugal lacking
the inferior angle.

Subfamily ERETHIZONTIWE.

Genus Erethizon P. Cuvier.

Body covered with hairs intermingled with loosely attached
quills or spines on back and sides ; tail short, thick, non-prehensile,
covered above with stiff hairs and spines, below and on sides
with stiff bristles; limbs short, strong; four toes in front and

152 RODENTS OP IOWA

five behind, all armed with strong, curved claws ; ears short ; p,nte-
orbital vacuity very large; crowns of molars with enamel folds
and more or less completely rooted ; mammaB four, all pectoral.

Dental formula^-l. 1/1 ; Pm. 1/1 ; M. 3/3=20.

A single form possibly occurs in Iowa.

Canada Porcupine.
Erethizon dorsatum dorsatum. p. 126

Suborder Duplicidentata.

Two pairs permanent upper incisors, the second very small and
placed immediately behind the others; at birth three pairs of in-
cisors are present but the outer one on each side is soon lost;
enamel of incisors continuous and not confined to anterior faces
of teeth; incisive foramina of palate large and usually confluent;
bony palate narrow from before backwards; tibia and fibula united
and articulating with the calcaneum.

This suborder is made up of two families, the Leporida?, con-
taining the true hares and rabbits, and the Oehotonidae, containing
the chief hares. These latter are small animals occurring in the
mountainous regions of western North America, arid do not occur
in Iowa.

Family LEPORID£.
HARES AND RABBITS.

Hind legs greatly elongated ; tail short, bushy ; soles of feet cov-
ered with fur ; eyes large ; upper lip deeply cleft ; cheek pouches
wanting but inside of mouth partly furry ; skull flat ; facial sur-
face of maxilla perforated ; palate narrow ; rami of mandible flat ;
clavicles imperfect.

Key to the Genera of Leporidae.

Interparietal not distinct in adult; supraorbital process usually
more or less expanded and subtriangular, usually somewhat diver-
gent from skull ; hind foot five or more inches Jong Lepus

Interparietal distinct in adult; supraorbital processes narrower,
the posterior notch usually narrower or wanting, owing to union
of postorbital process with skull; hind foot about four inches
long Sylvilagus

GENUS SYLVILAGUS 153

Genus Lepus Linnaeus.

Interparietal not distinct in adults ; supraorbital usually broadly
expanded, subtriangular in outline; second to fifth cervical ver-
tebras longer than broad ; median carina on dorsal surface ; hind
foot, in our forms, five inches or over.

Dental formula—I. 2/1 ; Pm. 3/2 ; M. 3/3—28.
Key to Species of Lepus.

1. Length of ear from skull to tip less than 3.75 inches;
total length 17.50 to 18.50 inches; hind foot five inches
or more.

Minnesota Varying Hare.
Lepus americrtmis phaeonotus. p. 130

Length of ear from tip to skull 3.75 inches or more;

total length more than 20.00 inches 2

2. Tail entirely white above and below; rump whitish in
winter, similar to rest of back in summer; total length,
24.00 inches.

White-tailed Jack Rabbit.
Lepus townsendi campanius. p. 131

Tail whitish below, the upper side marked with a black-
ish band extending backward from rump; rump patch
large, gray; total length, 23.00 inches.

Great Plains Jack Rabbit.
Lepus calif ornicus melanotis. p. 133

Genus Sylvilagus Gray.

Interparietal distinct in adult; supraorbital prominent, the post-
orbital process more slender and pointed than in Lepus; posterior
notch usually narrowed or obliterated on account of union of post-
orbital with skull ; second to fourth cervical vertebrae broader than
long; no carina on dorsal surface; one annual molt; hind foot, in
our representative, about four inches.

Dental formula^-L 2/1 ; Pm. 3/2 ; M. 3/3=28.

A single form occurs in Iowa.

Mearns' Cottontail.
Sylvilagus floridanus mearnsi. p. 134

154 RODENTS OF IOWA

List of References.

The following list of books and papers is arranged alphabetically
by authors, and is intended to provide a series of suitable working
references; some are general and some apply particularly to the
Iowa fauna. Other, and more complete reference tables and bib-
liographies will be found in the various volumes herein listed.
Allen, J. A., Notes on the Mammals of Iowa, Proc. Boston Soc.

Nat. Hist., XIII, 178-194, 1869 (1871).
Bailey, Vernon, The Pocket Gophers of the United States, U. S.

Dept. Agr., Bull. No. 5, 1895.

Beddard, F. E., Mammalia, Cambridge Nat. Hist., X, 458-507, 1909.
Bell, W. B., and Piper, Stanley E., Extermination of Ground

Squirrels, Gophers and Prairie Dogs in North Dakota, N.

Dak. Agr. Exp. Sta., Circ. 4, 1915.

Birdseye, Clarence, Some Common Mammals of Western Mon-
tana in Relation to Agriculture and Spotted Fever, U. S.

Dept. Agr., Farmers' Bull. 484, 1912.
Cory, Charles B., The Mammals of Illinois and Wisconsin, Field

Mus. Nat. Hist., Pub. 153, Zool. Series, XI, 1912.
Coues, Elliott, and Allen, J. A., Monographs of North American

Rodentia, Kept. U. S. Geol. Surv. Terr., F. V. Hayden, XI,

1877.
Elliott, Daniel Criraud, A Synopsis of the Mammals of North

America and the Adjacent Seas, Pub. Field Mus. Nat. Hist.,

Zool. Series, II, 1901.

Flower, W. H., An Introduction to the Osteology of the Mam-
malia, 1885.
Flower, W. H., and Lydekker, R., An Introduction to the Study

of Mammals Living and Extinct, 443-495, 1891.
Goldman, Edward A., The Eire Rats of North America (Genus

Oryzomp), N. A. Fauna No. 43, 1918.
Herrick, C. L., The Mammals of Minnesota, Geol. and Nat. Hist.

Surv. Minn., Bull. No. 7, 1892.
Hollister, N., A Systematic Synopsis of the Muskrats, N. A.

Fauna, No. 32, 1911.
Hollister, N., A Systematic Account of the Prairie-dogs, N. A.

Fauna, No. 40, 1916.
Howell, A. H., Revision of the American Harvest Mice, N. A.

Fauna, No. 36, 1914.
Howell, A. H., Revision of the American Marmots, N. A. Fauna,

No. 37, 1915.

REFERENCES 155

Howell, A. H., Revision of the American Flying Squirrels, N. A.

Fauna, No. 44, 1918.

Lantz, D. E., Meadow Mice in Relation to Agriculture and Horti-
culture, Yearbook U. S. Dept. Agr., 1905, 363-376.
Lantz, D. E., An Economic Study of Field Mice, U. S. Dept. Agr.,

Biol. Surv., Bull. No. 31, 1907.
Lantz, D. E., Methods of Destroying Rats, U. S. Dept. Agr.,

Farmers' Bull. No. 297? 1907.
Lantz, D. E., Use of Poisons for Destroying Noxious Animals,

Yearbook U. S. Dept, Agr., 1908, 421-432.
Lantz, D. E., Pocket Gophers as Enemies of Trees, Yearbook U. S.

Dept. Agr, 1909, 209-218 (3 pi.).
Lantz, D. E., How to Destroy Rats, U. S. Dept. Agr., Farmers'

Bull. No. 369, 1909.
Lantz, D. E., The Muskrat, U. S. Dept. Agr., Farmers' Bull. No.

396, 1910.
Lantz, D. E., The Muskrat as a Fur Bearer, U. S. Dept. Agr.,

Farmers' Bull. No. 869, 1917.
Lantz, D. E., House Rats and Mice, U. S. Dept. Agr., Farmers'

Bull. No. 896, 1917.
Miller, G, S., Genera and Subgenera of Voles and Lemmings, N. A.

Fauna, No. 12, 1896.

Morgan, L. H., The American Beaver and His Works, 1868.
Nelson, E. W., The Rabbits of North America, N. A. Fauna, No.

29, 1909.
Nutting, C. C., Report of the Committee on State Fauna, Proc.

la. Acad. Sci., II, 43-44, 1894.
Osborn, H., Catalogue of the Mammals of Iowa, Proc. la. Acad.

Sci., 1887-1889, 41-44, (1890).
Osborn, H., A partial Catalogue of the Animals of Iowa, Ames,

la, 5, 1891.
Osgood, W. H., Revision of the Mice of the American Genus

Peromyscus, N. A. Fauna, No. 28, 1909.
Preble, E. A., Revision of the Jumping Mice of the Genus Zapus,

N. A. Fauna, No. 15, 1899.
Quick, E. R., and Butler, A. W., The Habits of Some Arvicolinae,

Am. Nat, XIX, No. 2, 113-118, 1885.

Ruthven, A. G., and Wood, N. A., Notes on a Collection of Mam-
mals from Northwestern Iowa, Proc. la. Acad. Sci, XIX,
203-205, 1912.

156 RODENTS OF IOWA

Stoner, Dayton, Notes on Some Iowa Rodents, Proc. la. Acad.

Sci., XXIV, 353-356, 1917.
Van Hyning, T., and Pellett, Frank C., An Annotated Catalogue

of the Eecent Mammals of Iowa, Proc. la. Acad. Sci., XVII,

211-218, 1910.
Van Hyning, T., Additional Mammal Notes, Proc. la. Acad. Sci.,

XX, 311-312, 1913.
Various Authors, The Rat and Its Relation to the Public Health,

Treasury Dept., Public Health and Marine-Hospital Service

of U. S., 1910.

INDEX

Adams county, bounties in 117

Algona, Franklin's spermophile at , 38

Allamakee county, bounties in 117

porcupine in 126

Allen, J. A , 154

Alter, J. K 15

American porcupine 125, 151

Appanoose county, bounties in 117

Arctomys franklinii 36

Arctomys ludoviciana 40

Arsenic as poison 66

Atlantic, meadow mouse at 81

prairie harvest mouse at 78

prairie meadow mouse at 91

red squirrel at 26

woodchuck at 46

Audubon 55

B

Bachman 55

Badgers, enemies of rodents 33, 42, 115

Bailey, B. H 15, 124

Bailey, Vernon 32, 95, 154

Baird 55

Balanius 22

Barium carbonate as poison < • 65, 87

Barn owls1, enemies of rodents 33, 85, 115

Barred owls, enemies of rodents 85, 137

Barrel trap 64

Bayfield, northern white-footed mouse at 71

Bauman, Paul 15

Bearden, Virgil 15

Beavers 50, 145, 146

Beddard, F. E 154

Bell, W. B 121, 154

Benton county, bounties in 117

Berry, George H : 126

Biological Survey, Bureau of 54, 62, 63, 64, 72, 92, 120, 135, 136

Birdseye, Clarence 154

Bitterns, enemies of rodents 76, 85

Black-footed ferrets, enemies of rodents 42

Black rat . . ..." 147

INDEX

Black-tailed prairie dog 40, 145

Blasius • 93

Bounty on sphermophiles 33

on pocket gopher 115

Boyer river, beaver near 51

Bremer county, bounties in 117

Britt, Hudson Bay jumping mouse at 124

Broad-winged hawks, enemies to rodents 85

Brown rat 54, 147

Broad-winged hawks, enemies! of rodents 85

Buena Vista county, bounties in 117

Bull snakes, enemies of rodents 115

Burlington, northern white-footed mouse at 71

Butler, A. W 95, 155

O

Calhoun county, bounties in 117

muskrat in 101

Canada porcupine 126, 152

Canadian beaver 50

Carbon bisulphide as poison .' 35, 66

Carroll, Franklin's sphermophile at 38

Carroll county, bounties in 117

muskrat in 101

Calliope, prairie dog at 44

Cass county, prairie dog in 44

woodchuck in 46

Castor 146

canadensis canadensis • 50, 146

zibethicus 96

Castoridae 50, 142, 145

Cats, enemies of rodents 60, 137

Cedar Rapids, flying squirrel at 18

gray chipmunk at 29

Cement, use of, against rats .' 60

Cerro Gordo county, bounties in 117

Chariton, jack rabbit at • • 132

Charles City, gray chipmunk at 29

meadow mouse at 81

northern white-footed mouse at 71

red squirrel at 26

Cherokee, Franklin's spermophile at 38

Cherokee county, bounties in , us

Chickasaw county, bounties in 118

Chipmunk 26, 144

gray 27

gray striped 27

Citellus .143, 144

Franklini • 36, 144

DEX 159

tridecemlineatus tridecemllneatus 29, 144

Clarion, pocket gopher at 114

Clarke county, bounties in 118

Clay county, bounties in 118

Franklin's spermophile in 39

gray squirrel in 25

northern white-footed mouse from 71

prairie white-footed mouse in 74, 76

Clayton county, bounties in 118

Clear Lake, red squirrel at 26

Cooper's hawks, enemies of rodents 33, 137

Coif ax, flying squirrel at 18

Cory, Charles B : 14, 46, 97, 125, 154

Corning, Franklin's spermophile at 38

meadow mouse at • • 83

prairie meadow mouse at , . 91

prairie white-footed mouse at 76

Cottontail rabbit 134

Coues, Elliott 154

Council Bluffs, northern white-footed mouse at 71

woodland vole at 95

Crawford county, bounties in 118

Creston, jack rabbit at 132

Cricetinae . 148

Crows, enemies of rodents 76, 85

Cynomys 143, 145

ludovicianus ludovicianus 40, 145

D

Dallas county, bounties in 118

muskrat in 101

Davis county, bounties in 118

De.al, Merrill ". 15

Decorah, pocket gopher at •. Ill

Delaware county, bounties in 118

Des. Moines, Franklin's spermophile at 38

gray chipmunk at 29

gray squirrel at 25

Des Moines county, bounties in 118

Dickinson county, bounties in 118

. muskrat in 101

Dill, H. R 15

Dipus Jiudsonius 122

Dogs, enemies of rodents 60, 137

Eubuque, flying squirrel at 18

gray squirrel at 24

pocket gopher at 116

Dubuque county, bounties in 118

muskrat in 101

Dunlop, Kenneth 15

Duplicidentata .141, 152

160 INDEX

Eagles, enemies of rodents _._ 42

Eldora, Franklin's spermophile at 38

Elliott, Daniel Giraud 154

Emmetsburg, woodchuck at 46

Emmett county, bounties in 118

jack rabbit in 132

muskrat in 101

Enemies of spermophiles 33

Erethizon 151

dorsatum dorsatum 126, 152

Erethizontidae 125, 142, 151

Erethizontinae 151

Estherville, jack rabbit from : 133

Europe, woodland mouse in 93

F

Fairport, northern white-footed mouse from 71

prairie harvest mouse from 78

Fayette county, bounties in 118

Ferrets, enemies of rodents 42, 60

Fiber 146, 149, 150

zibethicus cinnamomimis 105, 150

zibethicus zibethicus 96, 150

Field, Henry 61, 129

Field Museum of Natural History 47

Fiene, Marcus 15

Flower, W. H 154

Floyd county, bounties in 118

Flying squirrel 17

Forest and Stream 103

Fort Dodge, beaver near 51

flying squirrel at 18

gray squirrel at 25

jack rabbit from 133

Fostoria, woodchuck at 46

Fox squirrel 19

distribution of 22

habits of 20

in Dubuque county 21

Foxes, enemies of rodents 33, 137

Franklin county, bounties in 118

muskrat in 101

Franklin's spermophile 36, 144

bounty on 39

control of 39

distribution of 37

food habits of 38

Fumigation 35

INDEX 161

G

Geomyidae 108, 142, 150

Geomys 150

bursarius bursarius 108, 150

Geske, M. X 101

Gibson, Joe 15

Gilmore, Franklin's1 spermophile at 38

Girdling of trees . 86

Glaucomys 142, 143

volans volans 143

Gnawing animals 141

Goldman, Edward A 154

Gopher, gray 36

pocket 108, 150

red 108

Shaw's pocket 108

striped 29

Goss' lemming mouse 106, 150

distribution of 107

Grant City, porcupine in 126

Gray chipmunk 27, 144

distribution of 28

habits of ' 23

Gray gopher 36

groundi squirrel 36

prairie squirrel J 36

squirrel .' 22

distribution of 24

habits of 23

striped chipmunk 27

Great horned owls, enemies of rodents 33, 137

Great Plains jack rabbit 133, 153

distribution of 132

muskrat 4 105, 150

distribution of 106

Green, Porter 15

Greene county, bounties in 118

Griswold, Sanf ord 15

Ground hog 45

shadow of 46

Ground squirrel, striped 29

thirteen-lined 29

Guillotine trap 62

Gwynn, Mr 121, 129, 132

H

Hamilton county, bounties in 118

Hampton, Franklin's spermophile at 38

Hancock county, bounties in 118

Hardin county, bounties in 118

11

162 INDEX

muskrat in 101

Hare, Minnesota varying 130

varying 130

Hares, fur of 128

habits of 127

and rabbits 126, 152

Harrison county, bounties in • • 118

prairie dog in 44

Hawks, enemies of rodents 59, 76, 85, 104, 113, 137

Henry county, bounties in 118

Herons, enemies of rodents 76, 85

Herrick, C. L 154

Hillsboro, prairie harvest mouse at 78

Hog-nosed snakes, enemies of rodents 115

Hollister, N. A.. 106, 154

Homestead, northern white-footed mouse at 71

prairie meadow mouse at 91

prairie white-footed mouse at 76

House mouse 52, 147

control of 54

food of 53

House rat 54

Howard, L. 0 67

Howell, A. H 107, 154, 155

Hoy 75

Hudson Bay jumping mouse , 122, 151

distribution of : 124

nabits of 123

Humboldt, flying squirrel at 18

Hydrocyanic acid as poison 67

Hypudaeus ochrogaster 87

Hystrix clorsata 126

I

Iowa, prairie dog in 44

Iowa City, chipmunk at 27

flying squirrel at 18

Franklin s spermophile at 38

gray squirrel at 25

meadow mouse from 81

northern white-footed mouse from 71

prairie harvest mouse from 76

red squirrel at , 26

woodland vole from 95

Iowa county, bounties in 118

muskrat in 101

Iowa Falls, flying squirrel at 18

Iowa Lakeside Laboratory 124

INDLX 163

Jack rabbit 131

great plains 133

Jasper county, bounties in 118

jack rabbit from 133

Jefferson, meadow mouse from 81

prairie harvest mouse from 78

prairie white-footed mouse from 76

Jefferson county, bounties in 118

Job, T. T 58

Johnson county, bounties in . . 118

great plains jack rabbit from 133

Jones county, bounties in 118

Jumping mouse 122, 151

food of 123

Hudson Bay 122

prairie 124

K

Kay, G. F 15

Kennicott, Robert 74, 75, 90, 101

Kingsley, J. P 115

Knoxville, flying squirrel at 18

Goss' lemming mouse from 108

great plains1 muskrat from 106

meadow mouse from 31

prairie} meadow mouse from 91

prairie white-footed mouse from 76

red squirrel at 26

Kossuth county, bounties in 118

muskrat in 101

Kubichek, W. F 15

L,

Lake Okoboji, Franklin's spermophile at 38

red squirrel at 26

Lake View, jack rabbit from 133

Lantz, D. E 67, 72, 82, 84, 87, 93, 100, 102, 111, 139, 155

Lee county, bounties in 119

Lees, James H 15

Lemming mouse, Goss' 106

Leporidae 126, 152

Lepus 152, 153

americanus phaeonotus 153

californicus melanotis ' 132, 133, 153

campestris 131

melanotis .'. . .133

townsendi campanius 131, 132, 153

sylvaticus mearnsi . .134

164 INDEX

Lime-sulphur wash 86, 139

Linn county, bounties in 119

Lizard creek, beaver near 61

Logan, Goes' lemming mouse at 108

prairie dog at 44

prairie harvest mouse at 78

prairie meadow mouse at 91

prairie white-footed mouse at 76

Longeared owls, enemies of rodents 85, 137

Lucas county, bounties in 119

muskrat in 101

Luxemburg, meadow mouse at 81

Lydekker, R .' 154

Lyon county, bounties in 119

M

Marengo, jack rabbit at : 133

Marmota 142, 146

monax monax 45, 146

Marmotinae 144

Marsh hawks, enemies of rodents1 33, 137

Marshall county, bounties in 118

Martin, J. R. 15

Maxim, Hudson 33

McGregor, gray chipmunk at 29

gray squirrel at 24

jack rabbit at 133

muskrat at 101

Meadow mouse 78, 149

control of 84

damage by 82

distribution of 81

food habits of 81

habits of 79

Meadow vole . 78

Mearns* cottontail rabbit 134, 153

Melvin, meadow mouse at 81

prairie meadow mouse at 91

prairie white-footed mouse at 76

Merriam, C. H.... 80

Mice, jumping 122, 151

pine 91, 93

and rats 52, 146

Microtinae 148

Microtuj * 146, 148, 149

ochrogaster ochrogaster 87, 1491

pennsylvanicus pennsylvanicus 78, 149

pinetorum nemoralis 91, 149

subterraneus . 93

INDEX 165

Milford, woodchuck at , 46

Miller, Charles Ill

Miller, G. S 147, 155

Mills county, bounties in 119

Mincks, Marion 15

Minks, enemies of rodents 59, 76, 85, 104, 137

Minnesota chickaree 26

• varying hare 130, 153

Mitchell county, bounties in •, 119

Monroe county, bounties in 119

Montgomery county, bounties in 119

Monticello, gray squirrel at 25,

prairie meadow mouse at 91

Moody, J. A 44

Morgan, L. H 155

Moscow, flying squirrel at 18

Mount Pleasant, Franklin's spermophile at 38

Mouse, Goss' lemming, . . .106

house . 52

Hudson Bay jumping • 122

meadow 78

northern white-footed , 69

prairie deer 73

prairie harvest. '76

habits of 77

prairie jumping 124

prairie meadow 87

prairie white-footed . * ; 73

woodland deer 4 ; -. -. .... » . •. a 69

Muridae 52, 142, 146

Murinae 147

•Mus . . 146, 147

bairdii .. •.-..-.-*-.-.•. ..v...^..^ ..;.;......; 73

bursariiis . . . . 108

monax ..... 45

muscullus * > 52, 147

norvegicus *................... 54

V pennsylvanica ............ ~. »....: t *;............ 78

'"rattus ^. .% 68

. sylvatlcus noveboracensis ...... -. . . . . . .... . . -. •-. ,Y.V.;. ••• . . ... 69

• v&lans » . . . . ; . . ............ 17

Muscatine, Franklin's spermophile aj 38

gray squirrel at ••••••. • 25

'Muscatine county, bounties iff. .119

'^ jack rabbits from. . ............ ... ............ ........ ....... .132

Muskrat ........;...........;..;...... 96, 150

* ': control of. . . .... ...:. V.V.V.V.V.V.V.V.V.V.Y.'. ; '. ... .... .104

1 damage by. . . * ...]:. . . . » . . . .v. i :::::::;:.::::::::::; . . . . . . V. .103; 105

H distribution of: : .-. /. . .'.\\-.'."//.\%\'.°.\v.v.v.'.v/:.v.v.". . . . :. . . . ... . . .101

'"economic importance -of.v.v.v.v.'.v.v.v.Y.Y. 7.'. . . . i . . .... . . ... .... .102

166 INDEX

- **'
enemies of ....................................................... 104

food of ...................................................... 100, 103

habits of ......................................................... 97

protection of ...................................................... 104

trapping of .............................................. ......... 103

great plains ...................................................... 105

fur, sales of ...................................................... 102

Musquash ......................................................... 97

Nelson, E. W ..................................... . ......... 15, 134, 155

Newton, prairie meadow mouse at .................................. 91

North Dakota, pocket gopher in .................................... 120

Northern gray squirrel ......................................... 22, 143

white-footed mouse ....................................... 53, 69, 148

control of ...................................................... 72

destruction by .................................................. 72

distribution of .............................. . ................... 71

habits of ....................................................... 71

Norway rat ......................................................... 54

Nutting, C. C ....................................... 15, 52, 65, 132, 155

O

Oak weevil, destroyed by fox squirrels ...................... ......... 22

Ocheyedan, prairie white-footed mouse at ........................... , . 76

Osage, gray squirrel at ............................................. 25

Osborn, Herbert ........................................... 108, 132, 155

Osceola, Franklin's spermophile at .................................. 38

meadow mouse at . .................................. * ............. 83-

Osceola county, bounties in ....................... .................. 119

fox squirrel in ...... ............................................. 22

Osgood, W. H ....................................................... 155

Osier, F. E ................................ . ................. . . ..... 114

Oskaloosa, Hudson Bay jumping mouse at ...... . ................... 124

Ottumwa, jack rabbit at ............................................ 132

prairie harvest mouse at ......................................... 78

prairie meadow mouse at ......................................... 91

prairie white-footed mouse at ...... , ............................... 76

woodland vole at. . ............................................... 95

Owls, enemies of rodents .......... . ........... 59, 73, 76, 85, 104, 113, 137

Oxford, gray squirrel at ............................................. 25

P

Palo Alto county, bounties in ........................................ 119

northern white-footed mouse from ... .............................. 71

prairie white-footed mouse in .................................. 74, 76

Paralta, gray squirrel at ............................................ 25

Pellett, Frank C.. ............. ........ 15, 19, 44, 46, 53, 78, 111, 130, 134

Peromyscus ............... . ................ ........ , ...... ..... 146, 148

leucopus noveboraceusis . ..148

INDEX 167

maniculatus bairdi 73, 143

Phosphorus as poison 66

Pine mouse 91, 93, 95

food of 95

Piper, Stanley E 121

Plymouth county, bounties in 119

Pocket gopher 108, 150

bounty on .*. 115

distribution of ,. m

food of 112

habits of 109

loss by 109

poisoning of 120

Poison formulae 35, 42

Polk county, bounties in 119

Pomeroy, Hudson Bay jumping mouse at 124

Popenoe, C. H 67

Porcupine, American 125, 151

Canada 126

Prairie deer mouse 73

Prairie-dog 40

control of 42

enemies of 42

formula of poison for 42

in Iowa 44

Prairie harvest mouse 76, 107, 148

distribution of 78

food of 78

habits of 77

in Kansas' 78

in Utah 78

jumping mouse 124

meadow mouse 87, 149

distribution of , 81, 91

habits of * ...... 8»

Prairie vole 87

Prairie white-footed mouse 53, 73, 148

control of 76

distribution of 74

habits of 74

Preble, E. A 123, 155

Putorius longicauda 33

Pteromyinae - 143

Q

Quick, E. R 95, 155

B

Rabbit, gray cotton-tail .134

at Shenandoah . . . . 129

168 INDEX

damage by . . ...................................................... 129

enemies of .......................... .............................. 137

food of .......................................................... . .136

fur of ............................................................ 128

habits of ..................................................... 127, 135

poisoning ........................................................ 138

trapping of .................................... . .................. 138

value of .......................................................... 129

jack ............... , ..... ........................................ 131

Meai ns' cotton-tail ............................ .................... 134

snow-shoe ....................................................... 130

Rabbits and hares .............................................. 126, 152

Rat, black .......................................................... 68

distribution of .................................................. 69

Rat, brown ......................................................... 54

control of ........................................................ 60

diseases carried by ............................................... 58

elimination of ...... .......................... .................... 67

enemies of ........................ . ................. . ............. 58

food habits of ...................................... .............. 57

habits of ......................................................... 55

loss due to ........................................................ 57

origin of ................................. ........................ 55

poisoning .................................. ...................... 65

trapping of ....................................................... 62

house ........................ • • .................................. 54

Norway .......................................................... 54

Rats and mice ................................................. 52, 146

Rattus ........................................................ 146, 147

norvegicus .......................... ......................... 54, 147

rattus .................. . . ........ . .......................... 68, 147

Red gopher .............. .......................................... 108

squirrel ................ . ......................... ............ 25, 143

distribution of ............. . .................................... 24

Red-shouldered hawks, enemies of rodents ............ : ............... 33

Red-tailed hawks, enemies of rodents .... ................... 33, 85, 137

Reithrodontomys ...... ____ ....................... . ............. 146, 148

megalotis dycliei ......................................... 76, 107, 148

Roberts, Jane E ..................................................... 15

Rock Rapids, Franklin's spermophile at .............................. 38

Rockwell City, Franklin's spermophile at ............................ 38

Rodentia, character of ... ............................... ............. 16

Rodents .................. ...... ........... ..... . ........ . ..... ... .141

Rodman, prairie white-footed mouse at . . . . . . . ." ." ". .' " ." . .* ." . .' . . . . . ."'.' .... 76

Rough-legged hawks, enemies of rodents ................ ........ 42, 137

Ruthven, A. G .................................. ................ 74, 155

Kuthven, Franklin's spermophile at ................. . ................ 38

muskrat at. . . . '.". . '.'.*. . . . ".'. . ... ...... .'.». . . . ..; . .,.. . , ... . . . . . . . 'v 91

'iSac county, beaver in . I ;.;.::: ...... . 51

INDEX

bounties in 119

porcupine in 126

rat in 55

St. Charles county, Missouri, Goss' lemming mouse at 107

Scheffer, T. H 110

Schroeder, Henry 15

Sciuridae 17, 142

Sciurinae 143

Sciurus 142, 143

carolinensis leucotis 22, 143

hudsonicus loquax 25, 143

hudsonicus minnesota 26

leucotis 22

niger rufiventer . . 143

striatus 26

tridecem-lineatus 29

Scott county, bounties in 119

Shaw's pocket gopher 108

Shenandoah, pocket gopher at 114, 121

prairie dog at 44

rabbits at 137

Short-eared owls, enemies of rodents 85, 137

Shrews, enemies of rodents 85

Sibley, fox squirrels at ." 22

Simplicidentata 141

Sioux county, prairie dog in . 44

Skunks, enemies of rodents t 33, 59, 76, 85, 115

Snakes, enemies of rodents 73, 76, 114

Snow-shoe rabbit 130

Somes, J. T 51

Somes, M. P 44, 51, 133

Southern flying squirrel. 17, 143

distribution of ... 18

red squirrel * 25

woodchuck .... ....... 45, 145

Spencer, Franklin's spermophile at , 38

Spermophile 17, 142

bounty on . . . . 33

control of . ... 34

poisoning of » . . . i 34

trapping of * 34

use of 34

Franklin's ., 36

striped ..... 29

thirteen-lined ... 29

Spurrell, John A 15, 22, 51, 55, 102, 126, 133

Squirrel 17, 142

flying . , . . 17

fox - . , . 19

gray 22

170 INDEX

gray ground 36

gray prairie 36

northern gray 22

red 25

southern flying 17

southern red 25

western fox 19

Steamboat Rock, flying squirrel at 18

Stephens, T. C 124

Stoner, Dayton 156

Striped chipmunk 26

gopher 29

ground squirrel 29

spermophile 29

control measures of 31

economic importance of 31

food habits of 31

habits of 30

Strychnia sulphate as poison 65, 73, 86, 138

Surber, T. . . . 108

Swainson's hawk, enemy of rodents 33, 137

Sylvilagus 152, 153

floridanus mearnsi 134, 153

Synaptomys '. 146, 150

cooperi gossii 106, 107, 150

T

Tama, prairie harvest mouse at 78

Tama county, beaver in 52

Tamias 142, 144

striatus griseus 27, 144

striatus striatus 26, 144

Terriers, as enemies of rodents 60

Thayer, flying squirrel at 18

gray chipmunk at 29

meadow mouse from 81

northern white-footed mouse from 71

prairie white-footed mouse from 76

woodland vole from 95

Thirteen-lined ground squirrel 29

spermophile 29, 144

Thomas, A. O 15, 111

Tiberghien, Shelt 102

Traer, chipmunk at 27

Trapping pocket gophers 121

Traps, types of 62

Trees, girdling of 86

protection of 140

INDEX 171

U

Union county, bounties in 119

United States Biological Survey, work of 14

Department of Agriculture

41, 43, 51, 54, 62, 63, 64, 72, 92, 103, 109, 112, 135, 136

Treasury Department 156

V

Van Hyning, T 108, 126, 130, 156

Varying hare 130

Vinton, prairie white-footed mouse at 75

Vole, meadow 78

prairie 87

woodland 91

W

Wall Lake, beaver near 51

flying squirrel at 18

fox squirrel at 22

jack rabbit at 133

muskrat at 102

northern white-footed mouse at 71

prairie harvest mouse at 78

prairie meadow mouse at 91

prairie white-footed mouse at 76

woodchuck at 46

Wapello county, bounties in 119

Warren county, bounties in 119

Waukon, gray squirrel at 24

meadow mouse at 81

prairie meadow mouse at 91

prairie white-footed mouse at 76

Wayland, flying squirrel at , 18

gray chipmunk at 29

northern white-footed mouse at .71

Wayne county, bounties in 119

Weasels, enemies of rodents 33, 59, 73, 76, 85, 115, 137

Welch nursery 121, 129, 132, 137

pocket gopher at 114

Wellhouse rabbit trap 137

West Bend, jack rabbit at 133

West Liberty, Franklin's spermophile at 38

(Western fox squirrel 19, 143

White-footed mouse, northern 53

prairie 53

White-tailed jack-rabbit 131, 153

distribution of 132

Wickham, H. F 15

Winnebago county, bounties in 119

muskrat in . 101

172 INDEX

Winneshiek county, bounties in 119

Witter, F. M 132

Wolves, enemies of rodents 85, 137

Wood, N. A 74, 155

Woodbury county, bounties in 119

Woodchuck 17, 45, 142

bounty on 48

burrow of ". . . . 4 46

food habits of .' 47

Woodland deer mouse 69

vole 91, 149

control of 95

damage by 95

distribution of 81, 95

food of 93

Wright county, bounties in. , i 119

Z

Zapodidae 122, 142

Zapodinae 151

Zapus 151

tiudsonius campestris 124, 151

Uudsonius hudsoniiis . . . . 122

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