JOWL OF ACMLTIAL RESEARCH 
Vou. XXVII Washington, D. C., February 23, 1924 No. 8 
BREEDING, FEEDING, AND OTHER LIFE HABITS OF 
MEADOW MICE (MICROTUS ) 1 
By Vernon Bailey 
Chief Field Naturalist, Division of Biological Investigations, Bureau of Biological 
Survey, United States Department of Agriculture 
INTRODUCTION 
The meadow mice, field mice, or ground voles, of the genus Microtus 
(2), 2 comprising numerous species and geographic varieties, are widely 
distributed throughout Europe, Asia, and North America, mainly in 
Temperate and Boreal Zones. Comparatively few species live in the 
Tropical or Lower Austral Zones, but many range north far beyond the 
Arctic Circle. Their greatest abundance and importance, however, is 
in the middle zones, the region of greatest agricultural production. 
These rodents are all small or of medium size, with a stout compact 
body, short legs, short tail and ears, small eyes, soft fur, and dull colors, 
as becomes ground dwellers and habitual burrowers into the earth. 
Some are semiaquatic, living in marshes or along the banks of streams; 
others occupy the meadows, uplands, and even the semiarid parts of 
our desert areas. With this wide range of adaptation one or two, or 
sometimes three or four, species in a locality occupy most of the fertile 
areas of the United States and Canada, where they become of economic 
importance as farm and orchard pests (4; 5, p. 121-123; g , p. gy-102; 
1 a; 12; 20 ). 
MOUSE PLAGUES 
In the Old World, meadow mice have for centuries presented serious 
agricultural problems, suddenly appearing in vast hordes that devoured 
the crops over extensive areas and causing heavy losses and much 
human suffering. Full accounts of these mouse plagues, which have 
appeared in Scotland, England, France, Germany, Italy, Greece, Hun¬ 
gary, Russia, Siberia, and Kamchatka, have been published. 3 
In our own country there are constant waves of abundance and diminu¬ 
tion in numbers of meadow mice, not country-wide, but rising and 
falling locally like swells of the ocean. These are noted in frequent 
complaints of unusual damage to crops or fruit trees by mice in different 
parts of the country, and some of the higher waves have been designated 
as mouse years or mouse plagues (16). 
One of these waves occurred during 1907 in the Humboldt Valley, 
Nevada (j< 5 ), a rich agricultural area then under irrigation and support¬ 
ing enormous areas of alfalfa that would yield two or three heavy cut- 
.tings a year with an aftermath for pasture during a part of the mild 
1 Received for publication, February 8 , 1924. 
* Reference is made by number (italic) to “ Literature cited,” p. 534 - 535 - . . , 
9 For references to accounts of mouse plagues in Old World countries, see list of literature in Lantz s 
report on field mice (r i, p. 64). 
Journal of Agricultural Research, 
Washington, D. C. 
(S 2 3 ) 
Vol. XXVII. No. 8 
Feb. 23, 1924. 
Key No. Q-i 
74027—24 - 1 
