There are 11 recognized subspecies of yellow-bellied marmot. These include Marmota flaviventris avara, M. f. dacota, M. f. engelhardti, M. f. flaviventris, M. f. fortirostris, M. f. luteola, M. f. nosophora, M. f. notioros, M. f. obscura, M. f. parvula, and M. f. sierrae. Yellow-bellied marmots are closely related to hoary marmots. The two species overlap in a small range in northwestern Montana and western Washington. Significantly high genetic variation between colonies is a result of moderately low gene flow from colony to colony coupled with genetic drift. Despite great genetic variation, gene flow is adequate enough to circulate genetic variants between colonies. This is due to the dispersal of many young yellow-bellied marmots from their birth colonies.
Communication between yellow-bellied marmots is mostly auditory and visual. There are three main vocalizations: the whistle, the undulating scream, and the tooth chatter. Six different whistles are recognized and may have more than one function, such as alerting and threatening. Screams usually respond to excitement or fear, and tooth chattering is used as a threat. Other animals such as American pikas and golden-mantled ground squirrels may respond to marmot alarm calls. Yellow-bellied marmots have cheek and anal glands. Scent marking occurs with cheek glands in conflict situations, having more of a dominance rather than territoriality function.
Communication Channels: visual ; acoustic ; chemical
Other Communication Modes: scent marks
Perception Channels: visual ; tactile ; acoustic ; chemical
Yellow-bellied marmots are classified as a species of "least concern" on the IUCN's Red List of Threatened Species. Currently, there are no major threats to the long-term persistence of this species.
IUCN Red List of Threatened Species: least concern
Yellow-bellied marmots are known carriers of the plague, caused by the bacterium Y. pestis. Although uncommon, humans that come into direct physical contact with this species may be at risk of contracting the plague.
Negative Impacts: injures humans (causes disease in humans )
In certain regions of its geographic range, yellow-bellied marmots killed for sport, food, or fur.
Positive Impacts: food ; body parts are source of valuable material
Interspecific competition with other species, such as hoary marmots may affect the distribution and density of yellow-bellied marmots. As seed predators, yellow-bellied marmots may serve as habitat engineers that contribute to the density and composition of plant communities throughout their geographic range. In addition, yellow-bellied marmots are important prey for a number of different aerial and terrestrial predators. Once abandoned, burrows likely serve as important habitat for other fossorial and semi-fossorial species.
Ecosystem Impact: disperses seeds; creates habitat
Yellow-bellied marmots are herbivorous, eating a large range of plant types, including grasses, flowers, and forbs. In late summer, large numbers of seeds are eaten. They are most likely not food limited, eating only 0.8 to 3.1% of available net primary production. Food might be limited in areas where snow cover remains into the spring. They are selective feeders and are known to reject parts of plants that are toxic.
Plant Foods: seeds, grains, and nuts; flowers
Primary Diet: herbivore (Folivore , Granivore )
Yellow-bellied marmots are distributed widely in the western United States and Canada. They range as far north as southcentral British Columbia and Alberta in Canada and as far south as the Sierra Nevada.
Biogeographic Regions: nearctic (Native )
Yellow-bellied marmots generally live in moderately warm, dry habitats at low to mid elevations. They are found in many different habitats, including semi-desert, woodland and forest openings, and the alpine zone. Those that live further south live at higher elevations. For example, in the White Mountains of California they are found only above 2000 m. Moreover, because of absence from valleys, southern populations are isolated from one other, forming isolated populations. In addition, congeners may affect their distribution. It can be inferred that the presence of hoary marmots inhibit the distribution of yellow-bellied marmots in certain high elevation areas, as both occupy subalpine and alpine areas. Yellow-bellied marmots inhabit vegetated fortified slopes or rock outcrops in meadows, which serve as support for the burrows that they reside in, as well as sunning and observation posts. The main entrance of burrow, which they dig themselves, is usually about 0.6 m deep into the ground, and extends about 3.8 to 4.4 m horizontally into the hillside. Many short tunnels branch from main passageway, sometimes connecting to other burrows. Burrows stay relatively stable and thus serve as preferable places to raise young, hibernate, and hide from potential predators. Burrow availability may affect marmot distribution, as well as visibility and safety from predators. Most yellow-bellied marmots occur around 2000 m in elevation.
Average elevation: 2000 m.
Habitat Regions: terrestrial
Terrestrial Biomes: desert or dune ; savanna or grassland ; forest ; mountains
Most yellow-bellied marmots live for 13 to 15 years in the wild. Predation, which accounts for 98% of summer mortality significantly limits the average lifespan of this species. A significant number of deaths occur during hibernation and emigration. Recently, sylvatic plague, caused by the bacterium Yersinia pestis, has had a significant impact on populations in California.
Range lifespan
Status: wild: 13 to 15 years.
Yellow-bellied marmots are a small to medium-sized rodents. Males weigh from 2.95 to 5.22 kg, with an average of 3.9 kg. Females range in mass from 1.59 to 3.57 kg, with an average of 2.8 kg. Total length ranges from 470 to 700 mm, with tail length ranging from 130 to 220 mm. Hind-foot length from 70 to 90 mm, and condylobasal length ranges from 68.0 to 99.8 mm. Males are longer than females and weigh significantly more. Also, individuals from low, arid-land habitats tend to be smaller than those from mesic, montane habitats. They have robust bodies, with short and broad heads. The head has a narrow interorbital region, with temporal ridges brought joining to form a low, short, sagittal crest. The posterior end of the palate lies obtusely, and the teeth of the upper jaw lie slightly more anterior than the teeth of the bottom jaw. The dental formula is 1/1, 0/0, 2/1, 3/3 = 22. The cheek teeth are high-crowned. Yellow-bellied marmots have small, well-furred ears, feet with five digits and an oval pad in the center of the sole of the hind foot, short and slightly curved claws with a rudimentary nail-bearing thumb, and ten mammae – two pectoral, two abdominal, and one inguinal pair.
The underfur of yellow-bellied marmots is soft, dense, and wooly on the back and sides of the body. Longer, coarse outer guard hairs with lighter tips and darker bases cover the entire body, making the overall color yellow-brown to tawny. Individuals are rarely dark brown and never black, except in melanistic individuals (common in populations in southern Rocky Mountains). There are also noticeable buffy yellowish patches on the side of the neck, white spots between the eyes, and a yellow or orange-russet color covering the belly, with feet a buffy, hazel, or dark brown color. There is great variety in color within subspecies. Yellow-belied marmots molt once annually during summer.
Range mass: 1.59 to 5.22 kg.
Average mass: 3.35 kg.
Range length: 470 to 700 mm.
Other Physical Features: endothermic ; homoiothermic; bilateral symmetry
Sexual Dimorphism: male larger
Average basal metabolic rate: 8.626 W.
Yellow-bellied marmots have a variety of aerial and terrestrial predators. Coyotes are their most important predator, followed by badgers, American martens, black bears, and golden eagles. Risk of predation may influence foraging behavior, social behavior, and habitat selection, as individuals attempt to reduce risk of predation by remaining in burrows for extended periods of time. Predation appears to be only a minor cause of mortality for colonial animals and is more significant among populations residing at habitat margins.
Known Predators:
Anti-predator Adaptations: cryptic
Yellow-bellied marmots are most often classified as polygynous. They can live as members of a colony, or as single or paired animals. About 75% of individuals live in colonies, 16% in “satellite sites”, and 7% in temporary sites. Satellite sites are secondary habitats consisting of only a few burrows. Those in colonies are members of harems, groups consisting of adult males, and females and their offspring. All males and about 40% of females are recruited from outside the colony. Reproductive rates at “satellite sites” are lower than in colonies and have more size fluctuation and shorter residencies than colonies and temporary/transient sites.
Mating System: polygynous ; cooperative breeder
Yellow-bellied marmots reach reproductive maturity by two years of age. Hence, no female yearlings produce offspring. Only 25% of two-year old females produce a litter. The testes of adult males are enlarged for several weeks when they awake from winter hibernation and then eventually regress to become the same size as juveniles. There is one breeding season per year, which starts and is concentrated in the first two weeks after they awake from winter hibernation. Gestation lasts for approximately 30 days, and litter sizes range from 3 to 8 pups, with an average of 4.32 pups. Adult females have an average corpus luteum count of 4.7. Newborn pups are 111 mm in length and weigh 33.8 g on average.
Breeding interval: Yellow-bellied breed once yearly.
Breeding season: Most populations of yellow-bellied marmots breed during May and June.
Range number of offspring: 3 to 8.
Average number of offspring: 4.32.
Average gestation period: 30 days.
Average weaning age: 7 weeks.
Average time to independence: 7 weeks.
Average age at sexual or reproductive maturity (female): 2 years.
Average age at sexual or reproductive maturity (male): 2 years.
Key Reproductive Features: iteroparous ; seasonal breeding ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; viviparous
Average birth mass: 33.8 g.
Average gestation period: 30 days.
Average number of offspring: 4.
Average age at sexual or reproductive maturity (male)
Sex: male: 730 days.
Average age at sexual or reproductive maturity (female)
Sex: female: 730 days.
There is little information available regarding parental care in yellow-bellied marmots. Mothers nurse pups for about 3 weeks, at which time pups emerge from the burrow. Parental care decreases substantially once pups emerge; however, strong social bonds remain for an extended period, especially in colonial populations.
Parental Investment: altricial ; female parental care ; pre-weaning/fledging (Provisioning: Female); post-independence association with parents
Marmota flaviventris is a species of ground squirrel found in certain higher elevation parts of western North America, occurring chiefly in meadows and open areas adjacent to woodlands. This species constructs a burrow for colonial living and enters hibernation near the onset of winter.
Distribution
Native distribution includes portions of Western North America (Frase & Hoffman. 1980) from south-central British Columbia and southern Alberta in Canada to the southern Sierra Nevada and White Mountains of southern California, Nevada, southern Utah, and the Sangre de Cristo Mountains in northern New Mexico. M. flaviventris typically occurs higher than 2000 meters in elevation. Because this species is restricted to higher elevations, it is frequently absent from valleys intervening between montane habitats. Correspondingly many populations of M. flaviventris are isolated from each other. (Blumstein et al. 2006)
Morphology
Marmota flaviventris is a small to medium-size rodent species, with yellowish tint to its fur on the undersides. The male has a body mass from 2.9 to 5.2 kilograms, with sexual dimorphism that features smaller females of body mass ranging from 1.6 to 3.6 kilograms. Adult body length ranges from 47 to 70 centimeters, with the females occupying the end of that range; adult tail length is typically 13 to 22 centimeters, again with females being on the lower end of the range. Each foot has five digits, an oval pad lying in the center of the sole of the hind foot; claws are abbreviated in length and somewhat curved with a rudimentary nail-bearing thumb.
This species exhibits a broad head that features a narrow interorbital region, with temporal ridges that join to create a low, short, sagittal crest. The posterior end of the palate lies obtusely; moreover, teeth of the upper jaw are positioned somewhat more anterior than those of the lower jaw. M. flaviventris exhibits smallish furry ears.
Habitat and behavior
Preferred habitat for this rodent includes high altitude meadows, especially at ecotones involving a forest edge or talus edge. The typical altitude range of this species is above 2000 meters above sea level. Burrows are usually constructed in soils that are below boulders or rock piles including talus edges; this technique is utilized in order to make the burrow less accessible to predators. Natural predators are coyote, wolf, badger, American eagle, black bear and fox; when M. flaviventris senses a predator or human nearby, it often vocalizes with a whistle sound, warning other members of its colony.
Colony sizes generally range from eight to 24 individuals, although some burrows are inhabited by only an adult pair, or in some cases even a sole individual. A typical colony includes one territorial male, one to four adult female mates and three to twenty juveniles. (Armitage. 2004) In some cases more than one adult male will be present in a single colony.
This marmot is an omnivore, and consumes a broad variety of forbs, grasses, insects and even bird eggs; among the forbs and shrubs, it may eat both leaves and berries.
Life cycle
M. flaviventris typically enters hibernation in an underground burrow prior to the onset of winter. It emerges from hibernation in the spring, with lower elevation populations emerging in the earlier parts of spring. Mating begins within several weeks of emergence from hibernation. Gestation is generally around thirty days, with the female producing a litter of three to eight offspring. Birthing occurs in the burrows, where the young remain for about another twenty to thirty days.
Conservation
This taxon is designated as of Least Concern as a conservation risk by the IUCN owing to its relative abundance throughout much of its range. (Lindzey & Hammerson. 2008) There are no major threats to this species from a conservation standpoint.
The yellow-bellied marmot (Marmota flaviventris), also known as the rock chuck, is a large, stout-bodied ground squirrel in the marmot genus.[2] It is one of fourteen species of marmots, and is native to mountainous regions of southwestern Canada and western United States, including the Rocky Mountains, Sierra Nevada, and Mount Rainier in the state of Washington, typically living above 2,000 metres (6,500 feet). The fur is mainly brown, with a dark bushy tail, yellow chest and white patch between the eyes, and they weigh up to approximately 5 kilograms (11 pounds). They live in burrows in colonies of up to twenty individuals with a single dominant male. They are diurnal and feed on plant material, insects, and bird eggs. They hibernate for approximately eight months starting in September and lasting through the winter.
Yellow-bellied marmots usually weigh from 1.6–5.2 kg (3 lb 8 oz – 11 lb 7 oz) when fully grown, though males typically weigh more than females.[3] The weight fluctuates quite drastically through the year, with the least measured in early spring and the most measured in early autumn.[4] Adult males typically weigh between 3–5 kg (7–11 lb) and adult females typically weigh between 1.6–4 kg (3+1⁄2–9 lb). They measure from 47–68 cm (18+1⁄2–27 in) in length, have a short tail measuring 13–21 cm (5–8+1⁄2 in) with buffy, reddish and black hairs and hindfoot measuring 7–9 cm (3–3+1⁄2 in).[3]
They have a rather frosty appearance with some of the guard hairs having pale tips with dark bands.[3] The yellow-bellied marmot has a broad and flat skull, dark head, and a dark nose with a white furry patch.[4] The pelage comprises coarse, long outer hairs and woolly, shorter underfurs.[3] They have a brown coat, a white patch of fur on the snout in front of the eyes.[4] Due to the bright yellow fur on their belly, sides of the neck, and throat, they get their scientific and common names.[4] Their ears are small and round, measuring 1.8–2.2 cm (11⁄16–7⁄8 in) in length, having a short white muzzle.[5] Their back is reddish-brown in color with grizzled black and light-grey tan.[4] Their feet are yellowish to dark brown to in color.[4] They gain additional fat reserves in the autumn, in preparation for hibernation.
The yellow-bellied marmot lives in southwestern Canada and western United States, including the Rocky Mountains and the Sierra Nevada.[5] Northwards, its range extends into the southern British Columbia and goes eastwards up to the montane and basin regions of Wyoming, eastern Montana, Colorado, and southern Alberta. Southwards, its range extends into northern New Mexico.[6] It inhabits steppes, meadows, talus fields, and other open habitats, sometimes on the edge of deciduous or coniferous forests. In Colorado, they are found from as low as 1,600 m (5,400 ft) to over 4,300 m (14,000 ft) of elevation.[3] In central and eastern Washington, they are common at low elevations.[7]
They are found in valleys, meadows, and foothills, and tend to occupy open areas which are free of vegetation.[1] Their territory is about 2.5 hectares (6 acres) around a number of burrows dug during the summer.[8] They choose to dig burrows under rocks, as it is less likely to be visible to predators. These predators include foxes, dogs, coyotes, wolves, and eagles. Upon seeing a predator, the yellow-bellied marmot whistles to warn the others in the area,[5][a] after which it typically hides in a nearby rock pile until there is no more threat.[8]
Marmots reproduce starting at around two years of age, and may live up to an age of fifteen. They reside in colonies of about ten to twenty individuals.[8] Each male marmot digs a burrow soon after it wakes from hibernation, and starts looking for females to reproduce. By summer, it may have up to four female mates. Litters usually average three to five offspring per female.[9] Only about half of those pups survive and become yearlings.[5] Marmots have a "harem-polygynous" mating system in which the male reproduces with two or three females at the same time.[9] Female offspring tend to stay in the area around their home, while male offspring typically leave when they are yearlings and will defend one or more females.[5]
Yellow-bellied marmots spend about 80% of their lives in their burrows, 60% of which is spent hibernation.[10] They often spend mid-day and night in a burrow as well.[10] These burrows are usually constructed on a slope, such as a hill, mountain, or cliff.[10] The hibernating burrows can be up to 5–7 m (16–23 ft) deep; however, the burrows constructed for daily use are usually only 1 m (3 ft 3 in) deep. Their hibernation period varies on elevation, but it is typically from September to May. Occasionally, they climb trees and other flora, though they are usually terrestrial.[5]
Yellow-bellied marmots are diurnal, and are less active during the night.[11] They are omnivores, but generally eat a wide variety of plants, as they are generalist herbivores.[12] They mostly feed on grass, grains, leaves, flowers, legumes, bird eggs, and insects.[5] Occasionally, they are also known to eat fruits and bark of fruit trees.[6] In food choice experiments, yellow-bellied marmots are known to reject plants containing defensive compounds.[12] Due to this, they consume flowers of lupinus, larkspur, and columbine, but avoid their shoots containing toxic compounds.[13] Their food choice depends upon the fatty acid and protein concentrations, which are well present in cinquefoil, cow-parsnip, and leaves of dandelion, which are also present in their diet.[12] In late summer, however, grasses, forbs, and seeds make up most of their diet.[4] They also like to feed on alfalfa and clover.[4] They drink less water, as their plant diet mostly serves their water requirements.[4]
Since 1996, it has been listed in the least concern category of the IUCN Red List of Endangered species.[1] As there are no major threats to this species and it is protected in several areas throughout its range, there is not much concern for serious conservation efforts to be put in place.[1]
The yellow-bellied marmot (Marmota flaviventris), also known as the rock chuck, is a large, stout-bodied ground squirrel in the marmot genus. It is one of fourteen species of marmots, and is native to mountainous regions of southwestern Canada and western United States, including the Rocky Mountains, Sierra Nevada, and Mount Rainier in the state of Washington, typically living above 2,000 metres (6,500 feet). The fur is mainly brown, with a dark bushy tail, yellow chest and white patch between the eyes, and they weigh up to approximately 5 kilograms (11 pounds). They live in burrows in colonies of up to twenty individuals with a single dominant male. They are diurnal and feed on plant material, insects, and bird eggs. They hibernate for approximately eight months starting in September and lasting through the winter.
