The Alaska Marmot also known as the Brooks Range Marmot or the Browers , is a species of rodent

Rodent

Rodentia is an order of mammals also known as rodents, characterised by two continuously growing incisors in the upper and lower jaws which must be kept short by gnawing....

 in the family Sciuridae. It is found in the scree

Scree

Scree, also called talus, is a term given to an accumulation of broken rock fragments at the base of crags, mountain cliffs, or valley shoulders. Landforms associated with these materials are sometimes called scree slopes or talus piles...

 slopes of the Brooks Range

Brooks Range

The Brooks Range is a mountain range in far northern North America. It stretches from west to east across northern Alaska and into Canada's Yukon Territory, a total distance of about 1100 km . The mountains top out at over 2,700 m . The range is believed to be approximately 126 million years old...

, Alaska

Alaska

Alaska is the largest state in the United States by area. It is situated in the northwest extremity of the North American continent, with Canada to the east, the Arctic Ocean to the north, and the Pacific Ocean to the west and south, with Russia further west across the Bering Strait...

, which provide some protection from predators. They eat grass, flowering plants, berries, roots, moss

Moss

Mosses are small, soft plants that are typically 1–10 cm tall, though some species are much larger. They commonly grow close together in clumps or mats in damp or shady locations. They do not have flowers or seeds, and their simple leaves cover the thin wiry stems...

, and lichen

Lichen

Lichens are composite organisms consisting of a symbiotic organism composed of a fungus with a photosynthetic partner , usually either a green alga or cyanobacterium...

 . These marmots range from 21.22 to 25.67 inches in length and 5.5 to 8.8 pounds in weight . 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

Groundhog Day

Groundhog Day is a holiday celebrated on February 2 in the United States and Canada. According to folklore, if it is cloudy when a groundhog emerges from its burrow on this day, it will leave the burrow, signifying that winter-like weather will soon end...

.

Etymology

Originally Marmota broweri was perceived as a synonym for M. caligata , but this was soon proven false when evidence was found that corroborated broweri as a unique species . Cytochrome b sequences were used to verify that M. broweri’s is its own distinct species .

History

Marmota broweri were sometimes hunted by alaska natives for food and often harvested by Eskimo hunters for their warm fur (about 20 marmots to make one parka) . An Eskimo hunter would spend all summer hunting marmots to make a parka, as it takes about twenty marmot skins to make one parka .

Marmot Day

Marmot Day

Marmot Day is an Alaskan holiday established to celebrate marmots and Alaska's unique culture. Although local festivals have been part and parcel of frontier life since time immemorial, Marmot Day became an official holiday on April 18, 2009, when the 26th Alaska State Legislature officially...

 is essentially Alaska's own version of Groundhog Day . Sarah Palin signed a bill in 2009 to make every February 2nd Marmot Day . The bill, introduce 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" . She didn't expect marmots to have any weather forecasting duties but rather hoped that the state would create educational activities regarding the marmot .

Status

The status of Alaska marmots is not well known due to the difficulties in finding them in their natural habitats . According to IUCN the Alaska marmot rates 3.1 “Least Concern”, signifying a relatively low concern in terms of risk . Although Alaska Marmots may be hunted, their population is stable and not at risk for endangerment . In fact, the Alaska Marmot has been declared the least threatened species of Marmot .

General

Alaskan Marmots are endothermic animals with bilateral symmetry . They possess a short neck, broad and short head, bushy tail, small ears, short powerful legs and feet, densely furred tail, body thickset covered in coarse hair . Adult Alaska marmots’ fur on their nose and the dorsal part of their head are black while the rest of their fur coat is usually of a dark color . Their feet may be light or dark in color . M. Broweri have tough claws adapted for digging , however their front limb thumbs does not have a claw but rather a flat nail . Their body is covered in coarse hairs . Their body size is highly variable due to hibernation cycles . For males, the average total length is 605 mm and the average weight is 3.63 kg . Adult females are slightly smaller, having an average length of 579 mm and 3.18kg .

Anatomical Distinctions

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

Location and distribution

In terms of global distribution, the Alaska marmot is nearctic . They exist in the mountains that lie north of the Yukon and Porcupine rivers in central and northern Alaska . 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 .

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

Habitat

The Alaska marmots live in polar habitats including the terrestrial tundra and mountain biomes . They are located at elevations of 990.60m to 1219.20m, but typically around 1127.76m . They are often found in boulder fields, rock slides and outcrops, terminal moraines, and talus slopes in Alpine tundra with herbaceous forage . They are often found on mountain slopes surrounding lakes, and are found less commonly away from a lake . They will burrow into permafrost soil surrounded by tundra vegetation and within ten meters a rocky ledge that can serve as an observation post . Alaska marmots live in relatively permanent winter dens that serve as a marmot colonies’ shelter for at least twenty years . A colony is essentially several individual family burrows built in close proximity to one another . Their dark fur is serves as a mild camouflage for their rocky environments . Wind is also very important to a Alaska Marmot's habitat and climate because it removes annoying mosquitoes . If there are a a large amount of mosquitoes in the area due to a lack of wind marmots will actually remain in their den until the climate changes .

Diet

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

Predation

Common Alaska Marmot predators include; wolverines, gray wolves, grizzly bears, and eagles

Eagles

The Eagles are an American rock band formed in Los Angeles, California in 1971 by Glenn Frey, Don Henley, Bernie Leadon, and Randy Meisner.With five number one singles, six Grammys, five American Music Awards, and six number one albums, the Eagles were one of the most successful musical acts of the...

 (the main predator for young marmots) .

Dangers

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

Ecosystem Impact

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

Social Behavior

Alaska Marmots are very social, living in colonies of up to 50 while all sharing a common burrow system . Marmots typically have their own personal den, while the young live with their mother and the father lives in a nearby den . 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 . The older marmots will defend and keep a look outlook while the young play . Solely dirt dug dens private limited protection, but a den built under rocks and boulders can prevent the risk of large animals, such as Grizzly bears, who can dig marmots out of their dirt dug dens .

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 .
Alaska Marmots also enjoy sunbathing and spending a large amount of time in personal grooming .

Hibernation

M. Broweri is one of the longer hibernating marmots, being documented to do so up to eight months annually . Alaska Marmots accumulate a thick fat layer by late summer to sustain them throughout the winter hibernation . Alaska marmots are active until when snow begins to fall, where they will go to their hibernaculums from around September until June . 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 . 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 . They then resettle in their dens in family units to communally hibernate for the winter .
Communal hibernation may be an adapted strategy to reduce metabolic cost while trying to keep their body temperatures above freezing . In order to seal their hibernaculum

Hibernaculum (zoology)

Hibernaculum plural form: hibernacula is a word used in zoology to refer to a place of abode in which a creature seeks refuge, such as a bear using a cave to overwinter. Insects may hibernate to survive the winter. The word can be used to describe a variety of shelters used by various kinds of...

off from the elements, they will plug their entrance with hay, earth, and stone . During hibernation many of their body functions decrease; body temperature (averages 4.5 and 7.5 degrees Celsius), heart rates, respiratory rates , and metabolic rates. Alaska Marmot hibernation is not continuous because they will awaken every three or four weeks in order to urinate and defecate . 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 . As an adaption to the artic environment and permanently frozen ground, Alaska Marmots breed prior to emerging from the winter den . The Alaska Marmots will generally emerge from the den during the first 2 weeks of May.

Reproductive

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

Captive Rearing

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) .

Evolution and Fossils

The Alaska marmot has ancestry to the epoch Pleistocene . There have been no known fossils of Marmota broweri . However, the M. flavescens fossil recovered from the Late Pleistocene age obtained on from the Trail creeks caves on the Seward Peninsula may have been incorrect . This fossil could be M. broweri .

The evolutionary lineages of the 14 marmot species distributed across the Holoartic are relatively ambiguous . Cytochrome b sequences indicated that M. Broweri is most likely related to M. caudata, cenzbieri, marmota, and monax . 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 . However, morphological data have linked M. broweri to M. camtschatica . 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 . The conflicting data pertaining to phylogeny creates inconsistent marmot lineage relationship hypotheses.