Microtus arvalis (Pallas, 1778) - Common vole (Meadow mouse).
Systematic position.Class Mammalia, order Rodentia, family Cricetidae, subfamily Microtinae, genus Microtus, subgenus Microtus (Schrank, 1798). The species contains from 20 to 30 subspecies (from different information sources). The fauna of the former USSR includes 9 to 12 subspecies.
Biological group.Rodent pests.
Morphology and biology.The size is rather small: body length, up to 130 mm, tail length, up to 49 mm (30-40% of body length). The dominate coloration is grey, with monochrome or weakly bicolorate tail; legs from back side do not differ in color from front side of body. Diploid set of chromosomes: 46. Inhabits forest-steppe, steppe and semi-desert areas. Populates predominantly cultivated landscapes (agrocenoses). Common vole like other species of grey voles builds shelters such as "composite holes" having multifunction purpose and ensuring survival in the open landscapes. Separate composite holes merge at high population density, forming large settlements occupying tens and hundreds of square meters.
Distribution.Major part of Western Europe, northern and central parts of Minor Asia, western regions of Mongolia and China. In the former USSR - from western state borders to Yenisei river and Altai mountains, including: Northwest, Central Black-Earth and Volga-Vyatka Regions, Non-Black-Earth zone, Ukraine, Moldova, Northern Caucasus and Transcaucasia, Lower Volga Basin, Kazakhstan, Southern and Middle Ural, Western Siberia.
Ecology.Having high ecological flexibility to various habitat conditions. Very high rate of population distribution depending on the environmental conditions (weather, agriculture, predators) and state of forage reserve. At low number the rodents survive in reservation habitats, i.e., in sowings of perennial grasses, pastures, uncultivated and abandoned lands. During population increases and mass outbreaks they invade sowings of grain, cultivated and industrial crops, feeding predominantly on green parts of plants, and saving some forage for winter. Under optimum conditions of feed and thermo exchange reproduction can take place over the course of the entire year; producing up to 7 broods, with an average of 5-7 young voles in each brood.
Economic significance.Damages practically all agricultural crops, especially sowings of grain crops and perennial grasses. During winter under snow gnaws round bark of fruit trees and saplings. The zones of high, moderate and low damage are marked within the limits of area. The intensification of agriculture causes area expansion and damage increase. A carrier of extra-hazardous diseases for human beings and domestic animals. Control measures include due and qualitative (loss-free) harvesting, holding crop rotations, deep plowing with turning-over of topsoil, baits with rodenticides.
Reference citations:Bashenina N.V. 1962. Ecology of Common vole. Moscow: MGU. 308 pp. (In Russian).
Gromov I.M., Polyakov I.Ya. 1977. Voles (Microtinae). Fauna of the USSR. Mammals. Leningrad: Nauka. V. 3(8): 504. (In Russian)
Sokolov I.I., ed. 1963. Mammals of the fauna of the USSR. Part I. Leningrad: LN SSSR. 638 pp. (In Russian).
Sokolov V.E., Bashenina N.V., eds. 1994. Common vole: the sibling species. Moscow: Nauka. 432 pp. (In Russian)