Common vole (Latin: Microtus arvalis) is a species of rodent of the genus Gray Voles.
Distributed in biocenoses and agrocenoses of the forest, forest-steppe and steppe zones of mainland Europe from the Atlantic coast in the west to the Mongolian Altai in the east. In the north, the range border runs along the coast of the Baltic Sea, southern Finland, southern Karelia, the Middle Urals and Western Siberia, in the south - along the Balkans, the Black Sea coast, Crimea and the north of Asia Minor. It is also found in the Caucasus and Transcaucasia, in Northern Kazakhstan, in the southeast of Central Asia, in the territory of Mongolia. It is found on the Korean islands.
The animal is small, the body length is variable, 9-14 cm. Weight usually does not exceed 45 g. The tail is 30-40% of the body length - up to 49 mm. The color of the fur on the back can vary from light brown to darkish gray-brown, sometimes with an admixture of brown-rusty tones. The abdomen is usually lighter: dirty gray, sometimes with a yellowish-buffy coating. The tail is either one-color or slightly two-color. Voles from central Russia are most lightly colored. There are 46 chromosomes in the karyotype.
The common vole breeds during the entire warm season - from March – April to September – November. In winter, there is usually a pause, but in closed places (haystacks, stacks, outbuildings), if there is sufficient food, it can continue to multiply. In one reproductive season, a female can bring 2–4 broods, with a maximum in the middle lane — 7, and in the south of the range — up to 10. Pregnancy lasts 16–24 days. There are an average of 5 cubs in the litter, although their number can reach 15, the cubs weigh 1–3.1 g. Young voles become independent on the 20th day of life. Start to breed at 2 months of age. Sometimes young females become pregnant already on the 13th day of life and bring the first brood at 33 days.
The average life expectancy is only 4.5 months, by October, most voles die, the young of the last litters winter and in spring they reproduce. Voles are one of the main food sources for many predators - owls, kestrels, weasels, ermines, ferrets, foxes and wild boars.
In summer they feed on grass, occasionally seeds and insects, in winter - grass, seeds, bark and shoots left under the snow. Usually they eat food on the surface of the earth, and in these places heaps of stalks remain. By the height to which the bark is nibbled on a tree undergrowth, in spring you can find out what was the greatest thickness of snow in winter.
Active around the clock, but more often at dusk and at night. They live in family groups (they are also called colonies). The group includes 2-3 broods of one pair of animals that settle in closely located minks on an area of 10-20 sq.m. Each settlement has up to 10 entrances and many cameras at a depth of up to half a meter. Burrows are connected among themselves and with places of feeding by a dense network of paths, often hidden by grass. Along the paths there are shelter minks, near which animals feed, usually no further than 20 m from the settlement. Build round nests of grass.
In winter, arrange moves under the snow. Almost no people come to the surface of the snow, and if they nevertheless find themselves in frost without shelter, they quickly freeze. At this time, the settlement of voles can be found by vertical vents in the snow and by the tracks of excavations undertaken by mouse foxes. In the spring, on the site of vole settlements, rollers from the ground and plant debris are visible, with which the animals clogged snowy passages.
Common vole is a widespread and numerous species that easily adapts to human economic activity and the transformation of natural landscapes. The abundance, as in many prolific animals, varies greatly by season and year. Outbreaks of numbers followed by long depressions are characteristic. In general, fluctuations look like a 3- or 5-year cycle. In the years of the greatest number of populations, the population density can reach 2000 individuals per ha, during the years of depression, falling to 100 individuals per ha.
Common Vole and Man
It is one of the most serious pests of agriculture, gardening and horticulture, especially during the years of mass reproduction. It harms grain and other crops in the vine and in ricks, nibbles the bark of fruit trees and shrubs. It is the main natural carrier of plague pathogens in the Caucasus, as well as causative agents of tularemia, leptospirosis, salmonellosis, toxoplasmosis and other diseases dangerous to humans.
Body - 140 mm, tail - 49 mm (no more than 30 - 40% of the body length). The length of the back foot is up to 18.5 mm, the skull 24 - 27.5 mm.
The color of the back is from light gray to dark brown. Sometimes there is an admixture of brown-rusty tones. The tail is one-color, less often slightly two-color. Blackish brown above, yellowish or whitish below. There are 6 corns on the foot.
The skull has underdeveloped frontotoparietal crests. Hearing drums are standard, not enlarged. Posterior molar with three external and four internal teeth. Both front without additional posterior-internal teeth. In the karyotype, 2n = 46.
Lifestyle. The species reaches its maximum abundance in open habitats in the steppe and forest-steppe zones, including cultivated lands. In floodplain meadows and cultivated lands, it penetrates deeply into the taiga in the north and into the semi-desert in the south through moistened biotopes. In the desert zone is present only in the mountains to an altitude of 3000 m above sea level. The view is common on the outskirts of large cities, in park areas, in wastelands, cemeteries and horticultural areas.
In the warm season, the activity of the species is observed at dusk, in the winter around the clock, but with interruptions.
Voles are adapted to life in cultivated lands. Often found on crops of winter and spring grains, perennial grasses. In winter, hay and straw are concentrated in ricks.
In the soil, gray voles dig long and complex burrows. Their area, depth and configuration depend on many factors. In particular, the type of soil, vegetation, season and burrow age. They are a system of underground interlocking passages with several food chambers and 1 - 2 nests. The nesting chamber is usually located at a depth not exceeding 25 cm, sometimes up to 50 cm.
In winter, voles can nest on the surface of the soil and under the snow. Winter nests in ricks are large and often serve simultaneously for 10 or more individuals.
Breeding. Sexual maturity occurs at 16-22 days of age. The species breeds mainly in the warm season, sometimes in winter in haystacks. One female can produce 88 offspring during the year. Pregnancy lasts 19-23 days. In one litter 4 - 8, up to a maximum of 13 cubs.
Profitable animals can participate in breeding. It depends on weather conditions and the geographical location of the habitat area. The group is characterized by outbreaks of mass breeding with a rapid recovery in numbers after a decline.
Nutrition. The diet of the species is diverse. The basic composition of the feed consumed varies depending on the nature of the biotope landscape and the season. In summer, these are green parts of plants, in autumn and winter - seeds and roots. Winter stocks are small.
Morphologically close species
In morphology (appearance), an Eastern European field vole is almost identical (Microtusrossiaemeridionalis) This species is positioned as a double species, which differs from that described only by a diploid set of chromosomes. There are 46 of the Common Vole, 54 of the Eastern European Vole. Some sources indicate that the East European voles obtained in the same place as the Common Voles may be smaller.
In addition, the Mongolian vole (Microtusmongolicus), also similar in morphology to the Common Vole (Microtus arvalis).
Common vole - pest of various crops. It damages cereals, Rosaceae, Asteraceae, and legumes. In greenhouses and gardens, cucumbers, cabbage, tomatoes, watermelons, melons are destroyed. Root vegetables willingly eat: beets, carrots, potatoes. In winter, strawberries, strawberries, raspberries, mosses, lichens are fed under the snow, gnawing the bark of young trees. Damages seeds in granaries. At the same time, animals are carriers of dangerous infections: plague, tularemia, leptospirosis, brucellosis, toxoplasmosis, erizipeloid, listeriosis, pseudotuberculosis and many others.
Mixing with the bait product (wheat, chopped potatoes, carrots, sugar beets or apples), applying the bait to burrows, other shelters, tubes, baits, boxes with special applicators:
Manual application with special applicators (measuring scoops made in farms) into burrows, other shelters, tubes, bait boxes:
Layout of ready-made lures at food enterprises and at home:
Manual application of biological rodenticides with special applicators in burrows, tubes, bait boxes, mechanized sieving with mounted fertilizer spreaders and seeders:
Layout of ready-made lures at food enterprises and at home:
Control measures: deratization measures
Sanitary and epidemiological well-being is due to the successful implementation of the entire range of deratization measures, including organizational, preventive, destructive and sanitary-educational measures to control rodents.
Organizational activities include a set of the following measures:
- financial and economic
- scientific and methodological
Preventive actions designed to eliminate favorable living conditions of rodents and exterminate them using the following measures:
- engineering and technical, including the use of a variety of devices that automatically impede the access of rodents to the premises and communications,
- sanitary-hygienic, including the observance of cleanliness in rooms, basements, in the territories of objects,
- agricultural and forestry, including measures for cultivating forests of recreational zones to the state of forest parks and maintaining these territories free of weeds, fallen leaves, dead trees and drying trees, this group of activities also includes deep plowing of land in the fields,
- preventive disinfestation, including measures to prevent the restoration of rodent numbers using chemical and mechanical means.
The task of carrying out this group of events lies with legal entities and individual entrepreneurs operating specific facilities and the adjacent territory.
Fighter activities carried out in settlements, on agricultural lands, as well as various foci of infectious diseases in order to completely clean the objects from rodents and are reduced to the following methods of deratization:
- physical, involving the use of mechanical devices for the destruction of rodents, ultrasonic emitters, glue traps, electrical barriers,
- chemical, during which rodenticides, rodenticides with synergists in various forms and repellents are used,
- biological, including the use of pathogenic microflora, parasites and predatory animals for the destruction of rodents.
These events are carried out by legal entities and individual entrepreneurs with special training.
In addition, when writing the article, the following sources were used:
Conservation Status and Conclusion
The common vole is a widespread species, most of whose populations, living in different natural zones, are relatively numerous. The reaction to human activities is ambiguous. Agricultural transformation of natural landscapes contributes to an increase in the number of species. In connection with this feature, it was proposed to call the common vole an agrocenophile (Tupikova et al., 2001). During the years of mass reproduction, it can cause significant damage to agriculture, has considerable epidemiological significance, being the carrier of the causative agents of tularemia, leptospirosis, toxoplasmosis and other diseases dangerous to humans. In this regard, control over the number of species is necessary.
The color of the fur of the voles can vary significantly from pale fawn-gray light fawn-brown to darkish gray-brown, sometimes with an admixture of brown-rusty tones. The abdomen is usually lighter: dirty gray sometimes with a yellowish-buffy coating. The tail is either one-color or slightly two-color. The back fur of the nominal race is brownish brown. Voles of the "arvalis" form from central Russia are more lightly colored, and the darkest color is observed in the form of "obscurus" (Ognev, 1950, Malygin, 1983).
The common vole is a small animal. Body length is variable. Weight usually does not exceed 45 g. The tail is 30-40% of the length of the head and body. Foot on average - 15.5 mm. The ears are small rounded slightly protruding from the fur. Condylobasal length of the skull on average - 24.5 mm, zygomatic width - 14.0, length in the upper row of molars - ranges from 5-7 mm, the lower - 4-6.5 (Ognev, 1950, Malygin, 1983, Meyer et al., 1996). Combs on the skull are weakly expressed. Upper M2 with two inward projecting corners. The vast majority of M3 individuals have the “typica” variant (Malygin, 1983). Its last hind lobe does not form a strongly pronounced arched bend. The lower M1 has at least 7 enclosed spaces, rarely - 8. There are 6 corns on the back foot (Ognev, 1950).
The range of the species is vast: from the Atlantic coast in the west to the Mongolian Altai in the east, from the Baltic Sea, Finland, Karelia, the Middle Urals and Western Siberia in the north to the Balkans, the Black Sea and Asia Minor in the south (Malygin, 1983, Baranovsky and others, 1994, Common Vole ..., 1994, Meyer et al., 1996). The species was recorded in Transcaucasia and on the territory of Mongolia. In Russia, the western border of common vole distribution coincides with the state one. In the north of the European part of the country comes from Karelia and the Leningrad region. In the south through Moldova and Ukraine to the north of the Caspian lowland and the Caucasus.
The range of habitats is diverse. A variety of factors can influence the biotopic preference of the common vole. First of all, natural and climatic. So, on the northern outskirts of its range in the taiga forest zone, a vole (form "obscurus") gravitates to field and meadow cenoses, reaching 49 and 30.2% of the total population of small mammals, respectively. It settles even in areas around livestock farms. According to Bashinina in 1979, 1980 and 1983. in the foothills of the Urals, the common vole lived in meadows and small agricultural crops, in vegetable gardens, orchards and clearings. In similar types of biotopes, it was also found in the Trans-Urals. Avoiding continuous forests in Western Siberia, field voles are common in sparse birch spikes and in thickets of shrubs along rivers (Malygin, 1983). But here, up to the Irkutsk region, she prefers habitats with well-developed grass cover (Bashinina, 1968, Shvetsov et al., 1981). In the more southern part of its range, M. a. obscurus tends to be more humid biotopes: floodplain meadows, depressions, gullies, irrigated gardens and vegetable gardens (Common Vole. 1994). However, it is also common here in xerophilic cenoses: dry steppes, fixed sands outside the desert zone (Nikitina et al., 1972, Tikhonov et al., 1996, Tikhonova et al., 1999). In the foothills of the Caucasus and Transcaucasia, the vole also gravitates towards agricultural lands. In this region, she mastered the slopes of the mountains, populating steppe plots, glades, river valleys, arable land. Rises to alpine meadows, lives on rocky areas. "Mountain" populations of this species are found at an altitude of 1800-3000 m above sea level.m.: in high mountain subalpine and alpine meadows and mountain oak, beech and hornbeam formations (Common Vole. 1994).
Voles of the arvalis form in the very north of the range and in the forest zone exhibit a biotopic distribution similar to the obscurus form, tending to meadow type cenoses and agricultural lands (Mokeyeva, Chentsova, 1981, Dobrokhotov et al., 1985, Teslenko, Zagorodniuk, 1986 , Tikhonov and others, 1992, Karaseva and others, 1994, and others). In the zone of deciduous forests and forest-steppe, it is often found in rarefied forest biotopes, along river valleys, beams, and forest belts.
According to our data, the common vole avoids territories subject to intense anthropogenic stress and transformation (Tikhonov et al., 1992, 1996, 1998, Tikhonov, Tikhonova 1997, Tikhonov, 1995).
Common vole is an ecologically plastic species. Typically a herbivorous rodent, the diet of which includes a wide range of feeds. According to generalized data, voles from different regions usually consume at least 80 plant species, giving preference to families of cereals, Asteraceae, and legumes (Common Vole. 1994). A seasonal change in feed is characteristic. The tendency to stockpile is expressed. In France, animals form "arvalis" made reserves of up to 3 kg (Renierd, Pussard, 1926). Similar food pantries were found near voles in the Leningrad Region. (Gladkina, Chentsova, 1971) and in Kazakhstan (Gladkina, 1972).
Common vole - a family-colonial species. The family, as a rule, consists of a female and her offspring of the 3-4th generation (Frank, 1954, Bashinina, 1962). In such settlements, animals dig a complex system of holes and trample a network of paths. In winter, they make snow nests on the ground. An ordinary vole is characterized by territorial conservatism, but if necessary, during harvesting and plowing fields, it can migrate to other biotopes, including haystacks, vegetable and granaries (Common Vole. 1994).
The species is characterized by seasonal and annual fluctuations in numbers. The minimum abundance of populations was noted in spring. The features of these fluctuations may also have a geographical specificity. In the pessimum of the range, prolonged depressions of the species abundance are possible. In the middle zone of Russia, they usually alternate with years of high numbers.
Ecological features of the common vole determine the ethological structure of its populations. Animals of this species do not form continuous settlements, but live in clearly defined colonies that are separated from each other and attached to their family groups (Frank, 1954, Bashenina, 1962). In all parts of its range, the species has polyphase circadian activity. On average, over a 3-hour period, voles have 2-4 acts of sleep, 3-9 cleansing, 2-6 nest improvements from 6 to 20 feedings and 14-47% of the total activity occur in locomotion (walking, jogging) (Common Vole 1994, own data).
The pronounced territoriality of voles is reflected in their social behavior. Intra-group interactions of animals are reduced mainly to simple identifying contacts, and less often to friendly ones (Zorenko, 1978, 1984, own data). An important element of social behavior, indicating the tolerance of individuals to each other, is crowding. Ordinary voles can be aggressive towards members of their group. More often this form of behavior is shown by males. The most acute is aggression towards alien individuals of their species and, especially, to Eastern European voles (up to the murder). Common voles are very emotional. We have noted cases of death of animals due to nervous overstrain during aggressive interactions.
Animals of this species are very careful, have a tendency to neophobia (Common Vole. 1994, Fedorovich et al., 2000). Under experimental conditions, for common research activities, common voles relied to a greater extent on the sense of smell and, to a lesser extent, on vibrissae, touch and vision (own data).
Depending on weather conditions in different regions of Russia, the reproductive period in common voles usually begins in March-April and ends in September-November (Common Vole. 1994, Tikhonova, Tikhonov, 1995, Tikhonov et al., 1998). In winter, there is usually a pause. But in closed stations (stacks, stacks, vegetable and grain storage), reproduction can continue in the winter. During the reproductive season in nature, females of the common vole can bring 2-4 broods, in laboratory conditions - more (Common Vole. 1994, Gladkina, 1996). The size of the brood depends on a number of reasons: age and physical condition of the females, season, habitat, mating model, and much more (Zorenko, 1972, Zorenko, Zakharov, 1986). According to the combined data, the average number of cubs in the litter of an ordinary vole is about 5 (Common Vole. 1994). A study of the breeding strategy of this species showed that its natural populations are subject to brood size (Tikhonov et al., 1999).