Lagurus lagurus
steppe lemming

Lagurus lagurus is found on the steppes of Eurasia from the Dnieper River of Ukraine in the West to the Yenisey River northeast of Kazakhstan in the East. The range extends through Kazakhstan into northwest China and northern Mongolia while reaching its southern limit at the Tien Shan Range. The northern limit of the range occurs at about 55ºN. In the Pleistocene the range of the genus Lagurus extended west to France and Britain.

There are four subspecies of steppe lemming. Lagurus lagurus lagurus is found in Ukraine and central Kazakhstan. The eastern subspecies, L.l. altorum, is found in southeastern Kazakhstan, northwest China, and Mongolia. Lagurus lagurus agressus, the northern subspecies, is found in the northern European portion of the former U.S.S.R. and in northern Kazakhstan. The isolated subspecies L. l. abacanicus is found in the Minusinsk basin in Krasnoyarsk, Russia. (Gromov and Polyakov, 1992; Ognev, 1964)

Steppe areas are regions with sufficient rainfall to support grasses, but too little moisture to support forest growth. Lagurus lagurus inhabits Eurasian steppes, feeding on grasses and herbs, and depending on the cover these provide to avoid predation. Steppe lemmings are found in particular abundance in areas of mixed feather grass and sheep’s fescue, but also in growths of wormwood (Artemesia). When feather grass dominates the flora, lemmings tend to be found in places lacking vegetation, such as in rocky areas. In general they prefer loose soils that allow for easier burrowing.

When living near agricultural lands, individuals often take up residence in fields and, in some cases, they have been known to live in storage buildings. However, as plowing damages their burrows, they must frequently make temporary moves away from the cultivated fields. This requirement leads to relatively low populations in agricultural areas. (Gromov and Polyakov, 1992; Ognev, 1964)

Steppe lemmings are relatively small Arvicolines having masses that vary seasonally from an average of 22 g in the winter to 34.8 g in the summer. The combined length of the head and body (for adults) ranges between 80 to 120 mm. Females are slightly larger than males. Lagurus can be distinguished from Lemmiscus by possession of a tail that is shorter than the hind foot, with lengths ranging from 7 to 19 mm. The eyes are small, and the pinnae are short, rounded, and lack an antitragus. The dorsal pelage is gray to gray-brown with a central black stripe running longitudinally, while the ventral pelage is light in color. Sexual dimorphism in size or color is uncommon in Arvicolinae. The pedes are almost completely covered in fur and have four pads. Females have eight teats.

Diagnostic molar characteristics include five closed enamel loops in M3, with the elongated posterior loop angled labially, and an M1 with seven to eight closed enamel loops. The skull is flat in profile and the zygomatic arches are wide and heavily built. The sagittal crest is absent.

Geographic variation includes trends of increasing body size and narrowing of the dorsal stripe from west to east. Individuals also tend to have paler fur to the east and south. More specific differences between the subspecies include:

L. l. lagurus: Narrow dark brown spinal stripe; ventral fur gray to yellow; tail white; winter fur more yellow than summer fur.

L. l. agressus: more prominent black spinal stripe; darkest fur; tail fur darker in color than L. l. lagurus.

L. l. abacanicus: larger skull than others; larger bullae; fur more gray than L. l. lagurus; very short tail.

L. l. altorum: lightest fur color (pale yellow); spinal stripe dark. (Gromov and Polyakov, 1992; Krebs, 2001; Longrove, 2005; Nowak, 1999; Ognev, 1964; Ralls, 1976)

Arvicoline lifespans are approximately 0.5 to 2.0 years. One source lists the maximum longevity for L. lagurus as 3.8 years. Most probably live no longer than one year. (de Magalhães, 2006; Krebs, 2001)

Steppe lemmings are burrowers that dig two types of burrows, domicile burrows and temporary burrows. The domicile burrow commonly has two to three openings, but only one distinct main entrance surrounded by a mound of raised earth. The main passage heads down at an angle of 30 to 40 degrees to a depth of up to 90 cm. A spherical nest area, located in the main passage, varies in size from about eight to 12 cm in diameter. There are also numerous blind ended passages, used when the animal is threatened, that extend up from the main burrow to within several centimeters of the surface. Separate, shallower, temporary burrows located within three meters of the main burrow are also used in times of danger.

This species is primarily crepuscular (active in the late evening and early morning). It has also been characterized as nocturnal, though it sometimes remains active through the day. Male and female Arvicolines typically maintain territories, which are marked using glandular secretions. Females engage in competition for resource-rich territories, while competition in males is focused on gaining access to females.

Lemmings are famous for their mass migrations. Steppe lemmings, though they are not true lemmings, also participate in mass migrations. Smaller scale migrations often occur locally as populations move from one food source to another due to seasonal changes in availability. However, mass migrations can occur in years when population densities rise too high due to mild autumns that allow continued breeding, or due to a lack of predators. (Krebs, 2001; Nowak, 1999; Ognev, 1964)

Home Range

A steppe lemming usually stays within six meters of its burrow. It will deplete the food supply around the burrow, then begin to maintain peripheral, temporary burrows that allow it to forage in more distant areas.

A study of the spatial distribution of L. lagurus revealed differences in distribution when population densities differed. In the spring, when population densities were low (6.1 individuals per hectare), L. lagurus lived in territorial family groups consisting of about six individuals. Each family group occupied an average territory of 0.2 hectares, and was separated from other groups by 73.3 m. In the autumn, when population densities were higher (34.0 individuals per hectare), no family groups could be distinguished. (Formozov, 1996; Mal'kova et al., 2004)

Arvicolines communcate via scent marking and vocalization. Scent marking is used to delineate territory and establish dominance. Calls are used for various social interactions including warning others of danger and making threats. Female steppe lemmings are particularly vocal just prior to giving birth. (Krebs, 2001; Ognev, 1964)

Lagurus lagurus is an herbivore feeding primarily on the above ground portions of plants. Steppe lemmings have a preference for Austrian wormwood (Artemisia austriaca), but will also take herbs, grasses, lichens, roots, tubers, and bulbs. The average daily food intake is 10.7 g in the summer. During this time only the best portions of the plant are eaten. The remains are left out or packed into the burrow and will serve to provide the animal with nourishment when other food is scarce. Steppe lemmings are able to process large amounts of abrasive vegetation because they possess continuously growing molars (and incisors). (Krebs, 2001; Ognev, 1964)

Steppe lemmings are prey for many predatory mammals and birds including: steppe polecats, ermines, weasels, foxes, domestic cats, eagle owls, buzzards, harriers, and kestrels. They avoid predation by lying flat on the substrate, staying under the cover of vegetation, entering their burrows, or by hiding in natural crevices or temporary burrows. (Formozov, 1996; Ognev, 1964)

Steppe lemmings are an important prey base for many carnivores of the steppe. In addition, their presence in an area can limit the success of other voles.

When population densities are high, the presence of steppe lemmings can be destructive to the ecosystem. In some cases they will reduce vegetation such that only hardy plants such as wormwood remain. In extreme situations where predation is limited, L. lagurus can transform steppe to semi-desert. (Ognev, 1964)

Steppe lemmings carry diseases such as tularemia (Francisella tularensis) and plague (Yersinia pestis). Incidence of these diseases is known to increase during years of high vole populations. In addition, steppe lemmings can destroy crops and pastures, leading to loss of income and cattle. (Ognev, 1964)

This species is used in research related to cancer and exposure to toxic chemicals. Steppe lemmings are also kept as pets. (Bolonina, 1960; Dryden, 1979)

This species is not threatened or endangered.