Marmota bobak ranges from central Europe, across Russia to central Asia. The species is most commonly found in scattered colonies along the Don and Donets rivers, and in the middle and southern Ural Mountains on the steppes of north Kazakhstan. The present range however, is only a fraction of the vast area formerly inhabited by M. bobak. (Ognev, 1963; Nowak, 1999)
Bobak marmots typically inhabit steppe ecosystems. They prosper on open rolling grasslands and along the edges of cultivated fields. These marmots appear to prefer low mountain slopes and territories between rivers. They thrive in regions with high densities of forbs and feather grasses. During the past 50 years, colonies have adjusted to grazing pressure and increasing row crop agriculture on the steppes of central Asia.
In areas where the steppes have been partially plowed, marmots inhabit hard ground and fallow land. Few animals venture onto the newly turned soil, because it offers little opportunity for burrow construction or feeding. Occasionally, marmots will burrow on unpaved roads that meander through the steppes. These burrows typically belong to young animals that are attracted to the site by the hard soil and abundant roadside weeds.
The Streletskaya steppe, home to a particularly large bobak marmot colony, sustains the fundamental habitat components upon which marmots depend. It is characterized by low hills, shallow ravines, small flooded riverine meadows, and sparse elm stands. Soils in this region are stony, with some sandstone deposits. Typical vegetation includes fescue (Festuca ovina), wheatgrass (Agropyrum sibiricum), lyme grass (Elymus junceus) and feather grass (Stipa stenophylla). Isolated populations of M. bobak have historically inhabited the edges of pine forests, however this cover type does not appear to support large colonies.
(Yurgenson, 1959; Ognev, 1963)
M. bobak is often described as a large analog of the North American prairie dog. Easily spotted while feeding on open grasslands, the species is characterized by a round stomach, stubby legs, and a short tail. Body length ranges from 490 to 575 mm. Males are generally somewhat larger than females.
The coat is generally short and dense, with guard hairs that extend slightly beyond the underfur. Mature marmots in fall pelage are usually straw colored to rusty with dark brown hair tips. On the upper part of the head, between the eyes, the dark hair tips are more concentrated, making the top of the head appear darker. Hair around the belly, chin, throat and groin is generally darker rust whereas the tip of the tail is usually dark brown. Pelage color variations also include a paler yellow coat with light brown guard hair tips and occasional albinism.
As in all members of the genus Marmota, pelage color depends on the season. The markings described above refer to a new, fall coat. During the spring and early part of the summer, marmots generally have worn coats that are scorched by the sun. The fur is generally lighter during this period.
Perhaps the greatest difference between M. bobak and other members of the genus Marmota lies in skull morphology. Generally M. bobak has a more massive skull with wider zygomatic arches and large supraorbital processes. Auditory bullae are broad and short. Total adult skull length ranges from 89 to 103 mm.(Blumstein, 1995; Ognev, 1963)
As these animals probably mate well out of sight of humans, mating system and mating behavior of this species has not been described.
Little data exist on the reproductive habits of M. bobak. Mating occurs during either hibernation, or at the onset of spring. A classic study conducted by E. M Korzinkina in 1935 indicated that M. bobak may employ delayed implantation. This phenomenon however has not been substantiated in subsequent research.
Sixty percent of adults breed within a given year. Gestation appears to vary between 40 and 42 days. Litters usually include 4 to 6 pups, with the average offspring number slightly greater than 5. Female marmots provide primary care for the young, though the male may fill a limited role in both litter protection and feeding once the young have emerged from the burrow.
Bobak marmots require 3 years to reach sexual maturity. Dispersers appear to leave the natal group after their second hibernation.
(Barash, 1975; Ognev, 1963; Yurgenson, 1959)
As in all mammals, the female provides milk for the growing young. All marmots are born relatively altricial. Young remain in the burrow until they are able to walk, around 1 month of age, and are weaned shortly after. Males may help to provide the young once they have emerged from the burrow. (Nowak,1999; Barash, 1975; Ognev, 1963; Yurgenson, 1959)
The exact lifespan of M. bobak in the wild is unknown, although captive marmots may live as long as 15 years.
Bobak marmots are highly gregarious and socially interactive. Family areas are generally large, and as many as 15 families may inhabit 1 square kilometer. Each marmot family consists of 2 to 5 adults and 2 to 6 maturing pups.
Bobak marmots are particularly active during the morning and at dusk. Evening activity usually continues until slightly after dark. During their most active phase, marmots spend between 12 and 16 hours above ground. Bobak marmots usually spend 5.5 months in hibernation.
According to recent observations, one or two marmots within a colony serve as sentinels. While the other marmots graze, the sentinel marmot remains alert, generally with its body erect and forepaws against its belly. If a predator approaches, the sentinel will emit an alarm call that warns the others of the eminent danger. While alarm calling increases the risk of predation for the altruist, it protects other colony members. Sentinel marmots are generally female. By virtue of natural dispersal patterns, females more directly related to other members of the colony than are males.
(Feldhammer et al., 1999; Barash, 1975; Ogev, 1963)
M. bobak principally feed on wild steppe grasses. Favorite plants include wild oats (Avena sativa), crested wheatgrass (Agropyrum cristatum), knotgrass, chicory (Cichorium intybus), clover (Trifolium repens), and lesser bindweed (Convolvulus arvensis). Although marmots prefer wild plants, they occasionally graze on vegetable gardens, sunflowers, and agricultural crops, such as potatoes. Intense feeding periods occur before winter in preparation for hibernation, and during early spring.
(Yurgenson, 1959; Ognev, 1963)
M. bobak fall prey to a variety of raptors and carnivores. Perhaps the most effective marmot predators are stray dogs and foxes. Historically, steppe wolves would also have counted among marmot enemies. Due to hunting and habitat destruction, however, wolves have all but disappeared from the landscape.
Effective avian predators include imperial eagles, golden eagles, and steppe eagles. Strong forelimbs, aggressive claws, and relative agility usually protect the marmot from smaller raptors such as marsh hawks and kites.
(Blumstein , 1995; Ognev, 1963)
Bobak marmots graze on a variety of native grassland vegetation. Consequently, they disperse grass seeds such as crested wheatgrass, knotgrass, and chicory. Complex burrow structures aerate compacted soil andabandoned colonies serve as den sites for other ground-dwelling mammals.
Because bobak marmots are a prey species, they are also important parts of the food web.
M. bobak once provided plush pelts for trappers and fur traders. These pelts were transformed into hats and fur coats as late as the mid-1930s. During the past 100 years, marmots were also harvested to feed starving Russian citizens during periodic famine. Historically, Russians have experimented with breeding marmots for captive fur production.
Isolated accounts document that M. bobak occasionally feed on garden vegetables such as potatoes, and corn. These reports however, describe atypical events that are not characteristic of these marmots.
bobak marmots are listed as "lower risk" by IUCN.
Extensive trapping and over-hunting have significantly reduced populations of M. bobak throughout its natural range. In fact, in 1915 it was noted that in the Streletskaya steppe alone, marmot hunters caught up to 40,000 animals in a single hunting season. Today, hunting is prohibited in many regions of Russia and the surrounding nations.
Recent increases in row crop agriculture have substantially altered grassland steppe habitats. As native grasses are carved out by the plow, the marmot is forced to migrate to new, fallow lands.
(Armatige, 1975; Nowak, 1999)
Embere Hall (author), University of Wisconsin-Stevens Point, Chris Yahnke (editor), University of Wisconsin-Stevens Point.
living in the northern part of the Old World. In otherwords, Europe and Asia and northern Africa.
young are born in a relatively underdeveloped state; they are unable to feed or care for themselves or locomote independently for a period of time after birth/hatching. In birds, naked and helpless after hatching.
having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.
uses smells or other chemicals to communicate
used loosely to describe any group of organisms living together or in close proximity to each other - for example nesting shorebirds that live in large colonies. More specifically refers to a group of organisms in which members act as specialized subunits (a continuous, modular society) - as in clonal organisms.
active at dawn and dusk
in mammals, a condition in which a fertilized egg reaches the uterus but delays its implantation in the uterine lining, sometimes for several months.
animals that use metabolically generated heat to regulate body temperature independently of ambient temperature. Endothermy is a synapomorphy of the Mammalia, although it may have arisen in a (now extinct) synapsid ancestor; the fossil record does not distinguish these possibilities. Convergent in birds.
parental care is carried out by females
union of egg and spermatozoan
an animal that mainly eats leaves.
A substance that provides both nutrients and energy to a living thing.
an animal that mainly eats seeds
An animal that eats mainly plants or parts of plants.
fertilization takes place within the female's body
offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).
parental care is carried out by males
having the capacity to move from one place to another.
the area in which the animal is naturally found, the region in which it is endemic.
breeding is confined to a particular season
remains in the same area
reproduction that includes combining the genetic contribution of two individuals, a male and a female
associates with others of its species; forms social groups.
digs and breaks up soil so air and water can get in
uses touch to communicate
that region of the Earth between 23.5 degrees North and 60 degrees North (between the Tropic of Cancer and the Arctic Circle) and between 23.5 degrees South and 60 degrees South (between the Tropic of Capricorn and the Antarctic Circle).
Living on the ground.
reproduction in which fertilization and development take place within the female body and the developing embryo derives nourishment from the female.
Armatige, K. 1975. Social behavior and population dynamics of marmots. Oikos, 26: 341-354.
Barash, D. 1975. Marmot alarm-calling and the question of altruistic behavior. American Naturalist, 94: 468-470.
Blumstein, D. 1995. "The Marmot Burrow- marmots of the world" (On-line). Accessed October 2, 2001 at http://www.marmotburrow.ucla.edu/bobak.html.
Feldhammer, , Drickamer, Vessey, Merritt. 1999. Mammalogy: adaptation, diversity, and ecology. Boston: McGraw-Hill Companies, Inc..
Nowak, R. 1999. Walkers Mammals of the World. Baltimore and London: The John Hopkins University Press.
Ognev, S. 1963. Mammals of U.S.S.R and Adjacent Countries- Rodents. Volume 5. Jerusalem: Israel Program for Scientific Translations.
Yurgenson, K. 1959. Notes on the behavior and food habits of *Marmota bobak*. Studies on Mammals in Government Preserves: 31-36.