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Overview

Brief Summary

Description

The Alaska Marmot lives in the Brooks Range, in northern Alaska, squeezing between big, bulky rocks on slopes to dig its dens. Denning on rocky ledges or under boulders offers them some protection from grizzly bears, which would otherwise dig them out. Wolverines and wolves also prey on Alaska Marmots, and eagles prey on young marmots. If an eagle is circling overhead or a predator is nearby, the marmots give warning calls and scurry to safety underground. In their harsh environment, the soil is permanently frozen. The marmots live in small population clusters close to productive plant-foraging areas. The nutritional quality of Arctic plants is low and the animals must consume a great deal to meet their requirements—and to prepare for hibernation. These marmots disappear underground with the first snowstorms, in September, and hibernate until June.

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Mammal Species of the World
  • Original description: Hall and Gilmore, 1934.  Canadian Field Naturalist, 48:57.
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Distribution

Alaska marmots (Marmota broweri) can only be found in the Nearctic region of the world. Hall and Gilmore (1934) reported that they have a very limited range in Northern Alaska, along the Arctic coast. Later work done by Slough and Jung (2007) suggests that the range of the Alaska marmot should include only the Brooks Range mountains in northern Alaska. They speculate that Alaska marmots might also occur in the Yukon, but there is currently no evidence to support this claim.

Biogeographic Regions: nearctic (Introduced )

  • Hall, E., R. Gilmore. 1934. Marmota caligata broweri, a new marmot from northern Alaska. The Canadian Field-Naturalist, 48: 57-60.
  • Slough, B., T. Jung. 2007. Diversity and Distribution of the Terrestrial Mammals of the Yukon Territory: A Review. The Canadian Field-Naturalist, 121: 119-127.
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Range Description

This species is known from the Brooks Range of northern Alaska in the United States, from near the coast of Chukchi Sea to the Alaska-Yukon border; perhaps also northern Yukon in Canada (Hoffmann et al., in Wilson and Reeder 1993).
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occurs (regularly, as a native taxon) in multiple nations

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National Distribution

United States

Origin: Native

Regularity: Regularly occurring

Currently: Present

Confidence: Confident

Type of Residency: Year-round

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Global Range: Brooks Range of northern Alaska from near coast of Chukchi Sea to Alaska-Yukon border; perhaps also northern Yukon (Hoffmann et al., in Wilson and Reeder 1993).

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Physical Description

Morphology

Alaska marmots are distinguished from other species of marmots by the black fur on top of their head, extending from the tip of the nose to the neck. These marmots have coarse hair that ranges in color from brown and black to white. Their back usually has brown hair, with a lighter brown underneath the black-tipped guard hairs. Their dark fur provides useful camouflage against the foliage and boulder fields in their habitat. Alaska marmots are fairly large (males are slightly larger than females) and heavy-bodied, with a short neck and a slightly flattened, bushy tail. The tail usually accounts for a third to a fifth of the total body length. Alaska marmots have black lips and black feet. The front feet sometimes have white markings. They have no fur on their palms (which have five pads) or their soles (which have six pads). Each limb has five digits with claws. The claws of the forelimbs are thick and curved for digging. The thumbs of the forelimbs have a flattened nail instead of a claw. Their legs are short, thick, and muscular. Alaska marmots have five pairs of mammae, for a total of ten. The eyes are small and circular and the furry ears are broad, short, and rounded. Alaska marmots have cheek pouches, but they are vestigial. Due to hibernation, weight varies across seasons, but they are able to gain weight quickly after emerging from hibernation. Alaska marmots experience one molt during the summer, but it does not seem to have a uniform pattern (Bee and Hall, 1956; Hubbart, 2011; Wilson and Ruff, 1999).

Alaska marmots are rodents, and so have the typical, chisel-like ever-growing incisors (Hubbart, 2011). Based on figures in Bee and Hall (1956), the cheekteeth of Alaska marmots have high ridges that fan out. Hubbart (2011) reports the dental formula of I 1/1, C 0/0, P 2/1, M 3/3 = 22. Compared to other species of marmots, Alaska marmots have a larger postorbital width and longer tympanic bullae. These marmots also have a short, deep angular process. The rostrum is fairly long and the postorbital process is wide. The zygomatic arches are complete and quite rounded. The sagittal crest and lambdoidal ridge are both fairly prominent (Hubbart, 2011).

Range mass: 2.5 to 4 kg.

Average mass: 3.41 kg.

Range length: 539 to 652 mm.

Average length: 592 mm.

Sexual Dimorphism: male larger

Other Physical Features: endothermic ; bilateral symmetry

  • Hubbart, J. 2011. Current Understanding of the Alaska Marmot (Marmota broweri): A Sensitive Species in a Changing Environment. Journal of Biology and Life Sciences, 2: 6-13.
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Size

Length: 60 cm

Weight: 3600 grams

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Size in North America

Length:
Average: 605 mm males; 579 mm females
Range: 582-652 mm males; 539-599 mm females

Weight:
Average: 3.6 kg males; 3.2 kg females
Range: 3-4 kg males; 2.5-3.5 kg females
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Ecology

Habitat

Alaska marmots have a scattered distribution, because they prefer a distinct habitat (Wilson and Ruff, 1999). They inhabit boulder fields and rocky outcrops on the slopes and in the valleys and canyons of the Brooks Mountains (Bee and Hall, 1956). They prefer particularly boulder fields and rocky outcrops where there are large enough spaces for them to dig dens between rocks. The entrances to the dens are usually protected by boulders, which helps to shield Alaska marmots from various predators. There are usually one or more observation points on top of the boulders near the den entrance, where Alaska marmots search for predators before beginning to forage (Wilson and Ruff, 1999). It is rare to find Alaska marmots living in boulder fields that are far from productive foraging sites (Bee and Hall, 1956).

Range elevation: 990.6 to 1219.2 m.

Average elevation: 1127.76 m.

Habitat Regions: polar ; terrestrial

Terrestrial Biomes: tundra ; mountains

  • Wilson, D., S. Ruff. 1999. The Smithsonian Book of North American Mammals. Washington: Smithsonian Institution Press.
  • Bee, J., E. Hall. 1956. Mammals of Northern Alaska. Lawrence, Kansas: University of Kansas.
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Habitat and Ecology

Habitat and Ecology
It occurs in arctic tundra, where there are extensive boulder fields, rock-slides, rock outcroppings, or talus. Requires secure den sites for protection against predation by grizzly bears. Young are born in underground burrows. A litter of 4-5 is born late spring to early summer. It eats grasses and other green plants, and hibernates in winter.

Systems
  • Terrestrial
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Comments: Dens located in extensive boulder fields or in talus slopes with large rocks adjacent to productive tundra (Wilson and Ruff 1999). Young are born in underground burrows.

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Migration

Non-Migrant: Yes. At least some populations of this species do not make significant seasonal migrations. Juvenile dispersal is not considered a migration.

Locally Migrant: No. No populations of this species make local extended movements (generally less than 200 km) at particular times of the year (e.g., to breeding or wintering grounds, to hibernation sites).

Locally Migrant: No. No populations of this species make annual migrations of over 200 km.

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Trophic Strategy

Alaska marmots are primarily herbvivorous, eating mostly the tundra vegetation growing near their burrows. They can also be classified as folivorous, granivorous, frugivorous, insectivorous, and omnivorous, due to the grasses, forbs, grains, legumes, fruits, and few insects in their diet, respectively. Due to the low nutritional quality of their food, Alaska marmots must spend a great deal of time foraging and eat a large quantity of food. This is why they often create dens and burrows very near their food sources. By the end of the summer, it is not uncommon for the contents of the stomach and digestive tract of Alaska marmots to account for up to one third of its total body weight. Alaska marmots compete indirectly with animals such as Dall's sheep, caribou, and other small rodents for food (Hubbart, 2011; Wilson and Ruff, 1999).

Animal Foods: insects

Plant Foods: leaves; seeds, grains, and nuts; fruit; flowers

Primary Diet: carnivore (Insectivore ); herbivore (Folivore , Frugivore , Granivore ); omnivore

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Comments: Eats grasses and other green plants.

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Associations

Alaska marmots are an important prey species for many animals, including grizzly bears, wolves, wolverines, and eagles Accipitridae (Hubbart, 2011). Alaska marmots are also a host species for a variety of parasites, including species of fleas, nematodes, and cestodes (Rausch and Rausch, 1971; Hubbart, 2011). Alaska marmots play an important role in soil enrichment and aeration. Digging dens and burrows helps to aerate the soil, while uneaten food, nesting material, and fecal matter help enrich it (Hubbart, 2011).

Ecosystem Impact: soil aeration

Commensal/Parasitic Species:

  • Rausch, R., V. Rausch. 1971. The Somatic Chromosomes of Some North American Marmots (Sciuridae), with Remarks on the Relationships of Marmota browerii Hall and Gilmore. Mammalia, 35: 85-101.
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Alaska marmots are preyed on by a number of species. Eagles, including the golden eagle, frequently prey upon juvenile marmots. Grizzly bears, wolves, and wolverines all pose a threat to juvenile and adult Alaska marmots (Wilson and Ruff, 1999).

Alaska marmots exhibit two anti-predator strategies. Because this is a social species, individuals take turns on lookout duty, communicating to other colony members with alarm calls when they spot a predator nearby. The observation points near den entrances are used by marmots on lookout duty (Bee and Hall, 1956). Observation points are also used by individuals outside of the den to search for predators before beginning to forage (Wilson and Ruff, 1999). The sounding of an alarm call causes group members to retreat back into their dens (Hubbart, 2011). Bee and Hall (1956) claimed that the alarm call of Alaska marmots can vary slightly depending on the type of predator and its location. They also observed that non-predator animals do not cause any kind of call. The fur color of Alaska marmots provide camouflage against the foliage of the mountainsides and boulder fields (Hubbart, 2011).

Known Predators:

Anti-predator Adaptations: cryptic

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Known predators

Marmota broweri is prey of:
Accipitridae
Ursus arctos
Gulo gulo
Canis lupus

This list may not be complete but is based on published studies.
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Known prey organisms

Marmota broweri preys on:
Insecta

This list may not be complete but is based on published studies.
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Life History and Behavior

Behavior

Communication in Alaska marmots, specifically alarm calling, is particularly well studied. This involves both a well-developed sense of hearing and a well-developed sense of sight. All adult Alaska marmots spend time on sentry duty, standing on top of observation points on the lookout for predators. When a predator is spotted, the marmot on sentry duty will emit an alarm call, which alerts the other individuals outside of the dens of the potential danger, causing them to retreat back inside their respective dens. Bee and Hall (1956) described the call as being low pitch and slurred. It is important to note that only predatory animals stimulate alarm calling, and that these calls can vary slightly based on the type of predator. For example, eagles stimulate approximately four consecutive calls, while humans elicit one to two. Predators far away from the colony result in a continuous call, though it seems less urgent (Bee and Hall, 1956).

Alaska marmots do not seem to benefit from the alarm calls of other species. However, it is possible that other species benefit from the alarm calls of Alaska marmots (Bee and Hall, 1956).

Communication Channels: acoustic ; chemical

Other Communication Modes: pheromones

Perception Channels: visual ; tactile ; acoustic ; chemical

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Cyclicity

Comments: Hibernates in winter.

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Life Expectancy

The lifespan of Alaska marmots are unknown. However, it is likely similar to that of related species, which are expected to live between 13 to 15 years. Nothing is known about the captive lifespan of Alaska marmots (Hubbart, 2011).

Typical lifespan

Status: wild:
13 to 15 years.

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Reproduction

Alaska marmots live in family groups, or colonies, consisting of males and females. A male will usually mate with one or more females living in dens near his own (Hubbart, 2011; Wilson and Ruff, 1999). Mating is stimulated by pheromones released from the anal scent glands of both males and females. Copulation usually takes place inside the den before Alaska marmots emerge from hibernation in the spring (Hubbart, 2011). There is no information available on the pre-copulation behavior of Alaska marmots. However, in the closely related Olympic marmots, these behaviors include sniffing, chasing, and fighting. Alaska marmots may exhibit similar behaviors (Barash, 1989).

Mating System: polygynous

Alaska marmots breed once a year around the time that they begin to emerge from hibernation. This is usually early in the month of June. Gestation time is five to six weeks and a female can have a litter of three to eight young, averaging usually four or five. Before giving birth, a female closes off her den so that she can be alone. Her litter is born altricial, but by six weeks old, the young are able to leave the den and explore outside. The timing of weaning of the litter is unknown; however, Hubbart (2011) reports that it may be at six weeks when the young are able to leave the den, as this is the common pattern for other species of marmot.

During their first year of life, juvenile Alaska marmots produce three fur coats, the third being similar to that of adults. Juveniles live and hibernate with their parents for two years, at which time they become independent adults. At three years of age, both males and females become sexually mature (Hubbart, 2011).

Breeding interval: Alaska marmots breed once yearly.

Breeding season: Alaska marmots mate in June, after emerging from dens at the end of hibernation period.

Range number of offspring: 3 to 8.

Average number of offspring: 4.

Range gestation period: 5 to 6 weeks.

Average time to independence: 2 years.

Average age at sexual or reproductive maturity (female): 3 years.

Average age at sexual or reproductive maturity (male): 3 years.

Key Reproductive Features: iteroparous ; seasonal breeding ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; viviparous

Both male and female Alaska marmots raise and protect their litter. This investment lasts for two years, at which time the juveniles become independent of their parents. During those two years, both parents provide shelter and protection year round (Hubbart, 2011).

Parental Investment: altricial ; male parental care ; female parental care

  • Barash, D. 1989. Marmots: Social Behavior and Ecology. California: Stanford University Press.
  • Hubbart, J. 2011. Current Understanding of the Alaska Marmot (Marmota broweri): A Sensitive Species in a Changing Environment. Journal of Biology and Life Sciences, 2: 6-13.
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Litter of 4-5 is born late spring to early summer.

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Conservation

Conservation Status

While they has a limited range and a scattered population distribution, Alaska marmots are not threatened and appear to have a stable population size. Hunting does not seem to have a significant or detrimental affect on the population (Wilson and Ruff, 1999).

US Federal List: no special status

CITES: no special status

State of Michigan List: no special status

IUCN Red List of Threatened Species: least concern

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IUCN Red List Assessment


Red List Category
LC
Least Concern

Red List Criteria

Version
3.1

Year Assessed
2008

Assessor/s
Linzey, A.V. & NatureServe (Hammerson, G. & Cannings, S.)

Reviewer/s
Amori, G. (Small Nonvolant Mammal Red List Authority) & Chanson, J. (Global Mammal Assessment Team)

Contributor/s

Justification
Listed as Least Concern because it has a relatively wide range, its populations are secure and there are no major threats.

History
  • 1996
    Lower Risk/least concern
    (Baillie and Groombridge 1996)
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National NatureServe Conservation Status

United States

Rounded National Status Rank: N4 - Apparently Secure

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NatureServe Conservation Status

Rounded Global Status Rank: G4 - Apparently Secure

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Population

Population
This species is apparently secure in its range (NatureServe). It occurs in family groups, with widely scattered populations. Although generally low in density, no estimates are available.

Population Trend
Stable
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Threats

Major Threats
There are no known threats to this species.
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Management

Conservation Actions

Conservation Actions
This species is not of conservation concern and its habitat is not currently under threat.
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Relevance to Humans and Ecosystems

Benefits

There are no known adverse affects of Alaska marmots on humans.

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Alaska natives have been known to hunt Alaska marmots for meat, and more often, for fur. The most common method used to hunt the animal is with rock fall traps (Hubbart, 2011). It has been reported that the fur of Alaska marmots is fairly valuable, with an average profit of six to eight dollars per pelt (Bee and Hall, 1956).

Positive Impacts: food ; body parts are source of valuable material

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Wikipedia

Alaska marmot

The Alaska marmot (Marmota broweri), also known as the Brooks Range marmot[2] or the Browers,[3] is a species of rodent in the family Sciuridae. It is found in the scree slopes of the Brooks Range, Alaska. They eat grass, flowering plants, berries, roots, moss, and lichen.[4] These marmots range from about 54 cm to 65 cm in length and 2.5 kg to 4 kg in weight.[5] Alaska celebrates every February 2 as "Marmot Day," a holiday intended to observe the prevalence of marmots in that state and take the place of Groundhog Day.[6]

Etymology[edit]

Originally Marmota broweri was perceived as a synonym for M. caligata,[7][8] but this was soon proven false when evidence was found that corroborated M. broweri as a unique species.[9][10][11] Cytochrome b sequences were used to verify that M. broweri as its own distinct species.[11]

History[edit]

Marmota broweri are sometimes hunted by Alaskan Natives for food and their warm fur.[12] An Eskimo hunter would spend all summer hunting marmots to make a parka, as it takes about 20 marmot pelts to make a single parka.[12]

Marmot Day is essentially Alaska's version of Groundhog Day.[13] Sarah Palin signed a bill in 2009 to officially make every February 2nd Marmot Day.[13] The bill, introduced by Senator Linda Menard, said, "It made sense for the marmot to become Alaska's version of Punxsutawney Phil, the Pennsylvania groundhog famed for his winter weather forecasts."[13] She did not expect marmots to have any weather forecasting duties but rather hoped that the state would create educational activities regarding the marmot.[13]

Status[edit]

The status of Alaska marmots is not well known due to the difficulties in finding them in their natural habitats.[5] According to IUCN: Red List of Threatened Species ver. 3.1, the Alaska marmot is considered to be a “Least Concern” status signifying a relatively low concern in terms of the dangers they face.[12] Although Alaska marmots may be hunted, their population is stable and not at risk for endangerment.[12] In fact, the Alaska marmot has been declared the least threatened species of marmot.[3]

Physical Description[edit]

General[edit]

Alaskan marmots are mammals.[12] They possess a short neck, broad and short head, bushy tail, small ears, short powerful legs and feet, densely furred tail, and a thick body covered in coarse hair.[4] Adult Alaska marmots’ fur on their nose and the dorsal part of their head are usually of a dark color.[12] Their feet may be light or dark in color.[4] M. broweri have tough claws adapted for digging,[4] however the thumbs of their front limbs do not have these claws but flat nails instead.[12] Their body size is highly variable due to hibernation cycles.[14] For males, the average total length is 61 cm and the average weight is 3.6 kg.[2] Adult females are slightly smaller, having an average length of 58 cm and 3.2 kg.[2]

Anatomical Distinctions[edit]

The retina of the eye of Alaska marmots is entirely lacking of rods, making their night vision quite poor.[3] They also lack the fovea of the eye, making their visual acuity much worse than other rodents.[3] The location of their eyes makes their field of vision very wide, sideways and upward.[3] All of their teeth will grow throughout their lifetime, resembling sharp rodent incisors.[12] There is a single pair of incisors in each jaw.[3]

Ecology[edit]

Location and distribution[edit]

In terms of global distribution, the Alaska marmot is nearctic.[5] Current distribution of the Alaska marmot include the Brooks Range, Ray Mountains, and Kokrines Hills.[15] They exist in the mountains that lie north of the Yukon and Porcupine rivers in central and northern Alaska.[5] However, there have been reports of Alaska marmots in the Richardson Mountains in the northern Yukon Territory but these sightings have not yet been confirmed.[5][16]

Alaska marmots are found scattered throughout Alaska as small colonies each consisting of various families.[17] Their locations have been documented in the Brooks Range from Lake Peters to Cape Lisburne and Cape Sabine that lies westward.[18] There have been sightings of marmots near rivers in the Northern Baird mountains and in the Mulik Hills.[19] They have also been sighted near copter Peak in the DeLong Mountains.[20] Species have also been secured south of the Brooks Range in the Spooky Valley and in the Kokrines Hills.[5]

Habitat[edit]

The Alaska marmots live in polar habitats including the terrestrial tundra and mountain biomes.[12] They are located at elevations of about 1000 m to 1250 m.[12] They are often found in boulder fields, rock slides and outcrops, terminal moraines, and Talus slopes [4] in Alpine tundra with herbaceous forage.[5] They are often found on mountain slopes surrounding lakes, and are found less commonly away from a lake.[21] To create their shelter Alaska marmots burrow into permafrost soil containing tundra vegetation, and within ten meters a rocky ledge serves as an observation post.[12] Alaska marmots live in relatively permanent winter dens that serve as a marmot colonies’ shelter for at least twenty years.[3] A colony is essentially several individual family burrows built in close proximity to one another.[4] Their dark fur serves as a mild camouflage in their rocky environments.[12] Wind is also very important to an Alaska marmot's habitat and climate because it removes annoying mosquitoes.[4] If there are large amounts of mosquitoes in the area due to a lack of wind, marmots will actually remain in their dens until the climate changes and the number of mosquitoes decrease.[12]

Diet[edit]

Tundra vegetation that grows on mountain sides are the primary nutrition source and they include; grasses, forbs, fruits, grains, legumes, and occasionally insects.[2][3] M. bromeri must eat large amounts of the arctic plants because they are low in nutritional value and for preparation of hibernation.[2] Alaska marmots are typically known as omnivores but they have also been described as insectivorous, folivorous, frugivorous, and granivorous.[3]

Predation[edit]

Common Alaska marmot predators include; wolverines, gray wolves, grizzly bears, and eagles (the main predator for young marmots).[4]

Dangers[edit]

Although dangers of direct human disturbance are minimal, climate dangers pose a real problem.[3] The Alaska marmot is arguably the most sensitive of the 14 Marmot species to anthropogenic disturbances, including climate change.[3]

Ecosystem Impact[edit]

Marmots enrich soil with uneaten food, nesting material, by their feces, and help to aerate the soil by their excessive digging.[4] They also serve as a minor food source for a variety of predators.[12]

Behavior[edit]

Social Behavior[edit]

Alaska marmots are very social, living in colonies of up to 50 while all sharing a common burrow system.[3] Marmots typically have their own personal den, while the young live with their mother and the father lives in a nearby den.[12] Especially in large colonies, the Alaska marmots utilize sentry duty rolls that are periodically rotated. A sentry marmot will alert the colony via a two-toned, high-pitched warning call (marmot vocalizations) if there is a predator in the area.[4] The older marmots will defend and keep a lookout for predators while the young play.[12] Solely dirt dug dens provides limited protection, but a den built under rocks and boulders can prevent the risk from large animals, such as Grizzly bears, who can dig marmots out of their dirt dug dens.[12]

M. broweri will mark their territory by secreting a substance from face-glands and rubbing the sides of their face on rocks around their den and various trails.[11] Alaska marmots also enjoy sunbathing and spending a large amount of time in personal grooming.[3]

Hibernation[edit]

M. broweri is one of the longer hibernating marmots, being documented to do so up to eight months annually.[3] Alaska marmots accumulate a thick fat layer by late summer to sustain them throughout the winter hibernation.[4] Alaska marmots are active until snow begins to fall, in which they will go to their hibernacula from around September until June.[2] Alaska marmots have special winter dens with a single entrance that is plugged with a mixture of dirt, vegetation, and feces during the entire winter hibernation period.[4] They are built on exposed ridges that thaw earlier than other areas, and the entire colony stays within the den from September until the plug melts in early May.[4] They then resettle in their dens in family units to communally hibernate for the winter.[14] Communal hibernation may be an adapted strategy to reduce metabolic cost while trying to keep their body temperatures above freezing.[22] In order to seal their hibernaculum off from the elements, they will plug their entrance with hay, earth, and stone.[12] During hibernation many of their body functions decrease; body temperature (averages between 4.5 and 7.5 degrees Celsius), heart rates, respiratory rates,[12][14] and metabolic rates. Alaska marmot hibernation is not continuous because they will awaken every three or four weeks in order to urinate and defecate.[3][14] Inside the hibernaculum den, the Alaska marmot has shown long-term hibernation adaptions by their ability to tolerate high CO2 levels and low O2 levels.[23] As an adaption to the Arctic environment and permanently frozen ground, Alaska marmots breed prior to emerging from the winter den.[4] The Alaska marmots will generally emerge from the den during the first 2 weeks of May.

Reproductive[edit]

Male Alaska marmots are polygynous, mating with the monogamous females living on their territory.[12] They are seasonal iteroparous and viviparous breeders that mate once per in the early spring and give birth about six week later with litter sizes ranging from 3 to 8 and an average litter size of 4-5.[12] The male and female Alaska marmots are involved in both raising and protecting the pups in their natal burrow.[12] In both sexes sexual reproductive behaviors are stimulated by odors released from anal scent glands.[12] Before birthing, the female will first close her den off and then she will give birth alone.[12] The Gestation period is about 5–6 weeks.[12] Newly born Alaskan marmots are altricial;[12] hairless, toothless, blind [4] and are quite vulnerable to predators. After about six weeks young marmots have thick, soft fur and they begin to temporarily leave the den.[12] They will go through 3 coats in their first year until their final one, which resembles adult Alaska marmots.[12] They will hibernate and live with their parents at least one year, they will be fully-grown after two years and reach sexual maturity from 2 to 3 years.[4][12] Marmots life span are not known but it is believed to be about 13–15 years.[12]

Captive Rearing[edit]

M. broweri has been reported to have been successfully reared in captivity and reintroduced into the wild (however there have been cases where captive rearing led to high rates of mortality).[3]

Evolution and Fossils[edit]

The Alaska marmot has ancestry to the Pleistocene epoch.[11] There have been no known fossils of Marmota broweri.[5] However, the M. flavescens fossil recovered from the Late Pleistocene age from the Trail creeks caves on the Seward Peninsula [24] is speculated to be an incorrect identification of the fossil [5] This fossil could be M. broweri.[5]

The evolutionary lineages of the 14 marmot species distributed across the Holarctic are relatively ambiguous.[25] Cytochrome b sequences indicated that M. broweri is most likely related to M. caudata, cenzbieri, marmota, and monax.[25] In support to the cytochrome b results, experimentation involving mitochondrial DNA has suggested that M. broweri is most likely related to M. caudata and M. menzbieri.[3] However, morphological data have linked M. broweri to M. camtschatica.[3] In addition, somatic chromosome analysis of marmots, ecological data and behavioral data have shown that there is a link between M. broweri and M. caligata.[26] The conflicting data pertaining to phylogeny creates inconsistent marmot lineage relationship hypotheses.

References[edit]

  1. ^ Linzey, A. V. & NatureServe (Hammerson, G. & Cannings, S.) (2008). Marmota broweri. In: IUCN 2008. IUCN Red List of Threatened Species. Retrieved 6 January 2009.
  2. ^ a b c d e f "North American Mammals: Marmota Broweri". Smithsonian Institution National Museum of Natural History. Retrieved 7 October 2011. 
  3. ^ a b c d e f g h i j k l m n o p q r Hubbart, Jason A. (2011). "CURRENT Understanding of the Alaska marmot (Marmota Broweri): A Sensitive Species in a Changing Environment". J Bio Life Sci: 6–13. Retrieved 28 November 2011. 
  4. ^ a b c d e f g h i j k l m n o p Curby, Catherine. "Marmot.Wildlife Notebook Series(On-line)". Alaskan Department of Fish & Game. Retrieved 2 December 2011. 
  5. ^ a b c d e f g h i j MacDonald, S. O. (2009). Recent Mammals of Alaska. Fairbanks, AK: University of Alaska. pp. 65–66. 
  6. ^ The Associated Press. "Alaska to celebrate its first Marmot Day," Fairbanks Daily News-Miner. Feb. 1, 2010. Accessed Feb. 1, 2010.
  7. ^ Hall, E.R.; R.M. Gilmore (1934). "Marmota caligata broweri, a new marmot from northern Alaska". Canadian Field Naturalist: 48:57–59. 
  8. ^ Hall, E.R. (1981). The mammals of North America. New York: Wiley-Inter science. 
  9. ^ Rausch, R. L.; V. R. Rausch (1965). "Cytogenic evidence for the specific distinction of an Alaskan marmot, Marmota broweri Hall and Gilmore (Mammalia: Sciuridae)". Chromosoma (Berlin): 16:618–623. Retrieved 25 November 2011. 
  10. ^ Hoffmann, R. S.; J.W. Koeppl; C.F. Nadler (1979). "The relationships of the amphiberingian marmots (Mammalia: Sciuridae)". University of Kansas Museum of Natural History, Occasional Paper: 83:1–56. 
  11. ^ a b c d Rausch, R. L.; V.R. Rausch (March 1971). "The somatic chromosomes of some North American marmots (Sciuridae), with remarks on the relationships of Marmota broweri Hall and Gilmore". Mammalia: 25:85–101. Retrieved 25 November 2011. 
  12. ^ a b c d e f g h i j k l m n o p q r s t u v w x y z aa ab ac ad Rasmussen, J. "Marmota Broweri (On-line)". Animal Diversity Web. Retrieved 25 November 2011. 
  13. ^ a b c d "Marmot Day: Alaska Adopts Its Own Version Of Groundhog Day". Green News: The Huffington Post. 1 February 2010. Retrieved 27 November 2011. 
  14. ^ a b c d Lee, T. N.; B. M. Barnes; C. L. Buck (2009). "Body Temperature Patterns during Hibernation in a Free-living Alaska marmot (Marmota Broweri)". Ethology Ecology & Evolution: 403–13. doi:10.1080/08927014.2009.9522495. Retrieved 26 November 2011. 
  15. ^ Gunderson, Aren M.; Brandy K. Jacobsen; Link E. Olson (2009). "REVISED DISTRIBUTION OF THE ALASKA MARMOT, MARMOTA BROWERI, AND CONFIRMATION OF PARAPATRY WITH HOARY MARMOTS". Journal of Mammalogy: 90(4):859–869. 
  16. ^ Youngman, P. M. (1975). "Mammals of the Yukon Territory". National Museums of Canada, Ottawa, Publications in Zoology: 10:1–192. 
  17. ^ Hoffmrann, R. S. (1999). "Alaska Marmot, Marmota broweri". The Smithsonian book of North American mammals (D. E. Wilson and S. Ruff, eds.) Smithsonian Institution Press, Washington, D.C., in association with the American Society of Mammalogists: 393–395. 
  18. ^ Childs, H. E. (1969). "Birds and mammals of the Pitmegea River region". Cape Sabine, northwestern Alaska, Biological Papers of the University of Alaska: No. 10. 
  19. ^ Dean, F. C.; D. L. Chesemore (1974). "Studies of birds and mammals in the Baird and Schwatka mountains". Alaska. Biological Papers of the University of Alaska: No. 15. 
  20. ^ Macdonald, S. O.; J. A. Cook (2002). "Mammal inventory of Alaska’s National Parks and Preserves". Northwest Network: Bering Land Bridge National Preserve, Cape Krusenstern National Monument, Kobuk Valley National Park, Noatak National Preserve, National Park Service Alaska Region, Inventory and Monitoring Program Annual Report 2001. 
  21. ^ Bee, J. W.; E.R. Hall (1956). Mammals of northern Alaska on the Arctic slope. University of Kansas Museum of Natural History: Miscellaneous Publication. pp. 8:1–309. 
  22. ^ Lee, T. N.; B. M. Barnes; C. L. Buck (2009). "Body Temperature Patterns during Hibernation in a Free-living Alaska marmot (Marmota Broweri)". Ethology Ecology & Evolution: 21:403–13. 
  23. ^ Williams, D.; R. Rausch (1973). "Seasonal Carbon Dioxide and Oxygen Concentrations in the Dens of Hibernating Mammals (Sciuridae)". Comparative Biochemistry and Physiology Part A: Physiology: 44(4): 1227–235. 
  24. ^ Yesner, D.R. (2001). "Human dispersal into interior Alaska: Antecedent conditions, mode of colonization, and adaptions". Quaternary Science Reviews: 20:315–327. doi:10.1016/S0277-3791(00)00114-1. Retrieved 26 November 2011. 
  25. ^ a b Steppan, Scott; et al. (1999). "Molecular Phylogeny of the Marmots (Rodentia: Sciuridae): Tests of Evolutionary and Biogeographic Hypotheses". Systematic Biology: 48(4):715–734. Retrieved 28 November 2011. 
  26. ^ Rausch, Robert; Virginia Rausch (1971). "The Somatic Chromosomes of Some North American Marmots (Sciuridae), with Remarks on the Relationships of Marmota Broweri Hall and Gilmore". Mammalia: 35 (1): 85–101. 
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Names and Taxonomy

Taxonomy

Comments: Marmota broweri was regarded as a synonym or subspecies of M. caligata, the hoary marmot of western North America, by Hall and Gilmore (1934) and Hall (1981), but Rausch and Rausch (1965), followed by Hoffmann et al. (1979), provided evidence that broweri is a distinct species. Jones et al. (1992) and Hoffman et al. (in Wilson and Reeder 1993) and Thorington and Hoffmann (in Wilson and Reeder 2005) recognized M. broweri and M. caligata as distinct species.

Hoffmann and Nadler (1968) and others believed this Alaska endemic to be most closely related to the black-capped marmot, M. camtschatica, of northeastern Asia, representing a late Pleistocene migrant to Alaska and subsequent speciation. However, this view was challenged by a molecular (cytochrome b) study (Steppan et al. 1999) that found no close sister species relationship to either M. camtschatica or M. caligata, suggesting that that the ancestry of the Alaska marmot dates back earlier in the Pleistocene, a view also put forward by Rausch and Rausch (1971). These and other studies (e.g., Cardini 2003, Polly 2003, Cardini et al. 2005) have so far failed in their attempts to reject hypotheses of either a Nearctic or Palearctic origin for this enigmatic marmot.

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