Alaska marmot | |
---|---|
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Mammalia |
Order: | Rodentia |
Family: | Sciuridae |
Genus: | Marmota |
Species: | M. broweri |
Binomial name | |
Marmota broweri | |
Range of Marmota broweri in Alaska. Its range also extends slightly into Canada. |
The Alaska marmot (Marmota broweri), also known as the Brooks Range marmot [3] or the Brower's marmot, [4] is a species of rodent in the family Sciuridae. Once considered to be the same species as the hoary marmot, it is now known to be unique. Alaska marmots are found in the scree slopes of the Brooks Range, Alaska. Specifically, they prefer to dwell on rocky, mountainous terrain, generally near lakes. They eat vegetation found on mountainsides, such as grasses, seeds, and lichen. Their relatively thick bodies are covered in dense, grey fur. They live in large colonies that consist of multiple families. During the winter, they hibernate for long periods of time in burrows. While not well researched, they are not believed to be particularly threatened, by human activity or otherwise. The Alaskan government has designated February 2 as "Marmot Day," a holiday intended to recognize the prevalence of marmots in the state, similar to the more widely celebrated American holiday of Groundhog Day.
Marmota broweri was described as a subspecies of the hoary marmot, M. caligata, [5] [6] but was later raised to species-level based on karyotypic differences. [7] [8] [9] Cytochrome b sequences were used to verify M. broweri as a distinct species. [9] Studies are still needed to evaluate the effects of genetic isolation on their fragmented distribution. [10]
The Alaska marmot's ancestry traces to the Pleistocene epoch. [9] There are no known fossils of Marmota broweri. [11] However, a fossil reportedly belonging to M. flavescens that is dated to the Late Pleistocene, recovered from the Trail Creek Caves on the Seward Peninsula [12] has been hypothesized as being an incorrect identification of an M. broweri fossil. [11]
The evolutionary lineages of the 14 marmot species distributed across the Holarctic are relatively ambiguous. [13] Cytochrome b sequences indicated that M. broweri is most likely related to M. caudata, M. menzbieri, M. marmota, and M. monax. [13] 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[ citation needed ]. However, morphological data have linked M. broweri to M. camtschatica. [4] In addition, somatic chromosome analysis, ecological data, and behavioral data have shown that there is a link between M. broweri and M. caligata. [9]
In terms of global distribution, the Alaska marmot is Nearctic. [11] Alaska marmots inhabit the mountains that lie north of the Yukon and Porcupine rivers in central and northern Alaska—including the Brooks Range, Ray Mountains, and Kokrines Hills. [14] [11] 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. [11] [15] Their overall distribution is still poorly understood. [10] The International Union for Conservation of Nature (IUCN) does not consider their population "severely fragmented," but the Alaska Department of Fish and Game has described it as "patchy." [1] [10]
Alaska marmots are found scattered throughout Alaska as small colonies, each consisting of several families. [16] Their locations have been documented in the Brooks Range from Lake Peters to Cape Lisburne and Cape Sabine. [17] There have been sightings of the species near rivers in the Northern Baird mountains, in the Mulik Hills, [18] near Copter Peak in the De Long Mountains, [19] and south of the Brooks Range in the Spooky Valley and in the Kokrines Hills. [11]
The Alaska marmots are found in grassland, inland cliffs, and mountain peaks. They are located at elevations of about 1,000 metres (3,300 ft) to 1,200 metres (3,900 ft). [1] They are often found in boulder fields, rock slides and outcrops, terminal moraines, and Talus slopes [20] in Alpine tundra with herbaceous forage. [11] The species inhabits slopes surrounding lakes, and are found less commonly away from lakes. [21] Alaska marmots inhabit permanent winter dens that are used for as long as twenty years. [4] The entrances are plugged with vegetation, dirt, and feces. These dens are usually located near a ledge which functions as an observation post. A colony consists of several individual family burrows built in close proximity to one another. Their fur coloration helps them blend in amongst rocks. [20]
Alaskan marmots possess a short neck, broad and short head, small ears, short powerful legs and feet, bushy and densely furred tail, and a thick body covered in coarse hair. [20] Adult Alaska marmots’ fur on their nose and the dorsal part of their head are usually of a dark color. [22] Their feet may be light or dark in color. [20] M. broweri have tough claws adapted for digging, [20] however the thumbs of their front limbs do not have these claws but flat nails instead. [22] Their body size is highly variable due to hibernation cycles. [23] For males, the average total length is 61 centimetres (24 in) and the average weight is 3.6 kilograms (7.9 lb). [3] Adult females are slightly smaller, having an average length of 58 centimetres (23 in) and 3.2 kilograms (7.1 lb). [3]
The retina of the eye of Alaska marmots is entirely lacking of rods, making their night vision quite poor. [4] Their eyes also lack a fovea, making their visual acuity much worse than other rodents. [4] The location of their eyes makes their field of vision very wide, sideways and upward. [4] Like other rodents, Alaska marmots have incisors that do not stop growing. [10] There is a single pair of incisors in each jaw. [4]
Compared to the very similar hoary marmot, also found in Alaska, M. broweri are much softer. They also lack the characteristic white facial patch of hoary marmots. The groundhog, another Alaskan marmot, can be told apart by its more reddish coloring, as compared to the grayer Alaskan and hoary marmots. [20]
The Alaska marmot's main nutrition source is vegetation that grows on mountain sides, which includes grasses, flowers, fruits, grains, legumes, lichen, and occasionally insects. [3] [4] [20] M. bromeri must eat large amounts due to the low nutritional value and the need to prepare for hibernation. [3] Alaska marmots are typically known as omnivores but they have also been described as insectivorous, folivorous, frugivorous, and granivorous. [4]
The Alaska marmot is preyed on by wolverines, gray wolves, grizzly bears, coyotes, and foxes. [20] Eagles, particularly the golden eagle, are a major predator of younger marmots. [22]
A sentry marmot will alert the colony via a two-toned, high-pitched warning call if there is a predator in the area. [20] The older marmots will defend and keep a lookout for predators while the young play. Dens dug solely in dirt provide limited protection, but a den built under rocks and boulders can prevent the risk from large animals, such as grizzly bears, who dig marmots out of their dirt-dug dens. [22]
Marmots enrich soil with uneaten food, nesting material, and their feces, and help to aerate the soil with their digging. They also serve as a food source for a variety of predators. [20]
Alaska marmots are very social, living in colonies of up to 50 while all sharing a common burrow system. [4] 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 roles that are periodically rotated. [22]
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. [9] Alaska marmots also enjoy sunbathing and spending a large amount of time in personal grooming. [4]
M. broweri is one of the longer hibernating marmots, being documented to do so up to eight months annually. [4] Alaska marmots accumulate a thick fat layer by late summer to sustain them throughout the winter hibernation. [20] Alaska marmots are active until snow begins to fall, when they will go to their hibernacula from around September until June. [3] Alaska marmots have special winter dens with a single entrance that is plugged with a mixture of dirt, vegetation, and feces during the winter hibernation period. [20] These winter dens 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. [20] They then settle in their dens in family units to communally hibernate for the winter. [23]
Communal hibernation may be an adapted strategy to reduce metabolic cost while trying to keep their body temperatures above freezing. [23] During hibernation many of their body functions decrease such as body temperature (averages between 4.5 °C (40.1 °F) and 7.5 °C (45.5 °F)), heart rates, and respiratory rates. [22] [23] Alaska marmot hibernation is not continuous because they will awaken every three or four weeks in order to urinate and defecate. [4] [23] 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. [24] As an adaption to the Arctic environment and permanently frozen ground, Alaska marmots breed prior to emerging from the winter den. [20] The Alaska marmots will generally emerge from the den during the first two weeks of May.
Male Alaska marmots are polygynous, mating with the monogamous females living on their territory. They are seasonal iteroparous and viviparous breeders that mate once in the early spring and give birth about six weeks later with litter sizes ranging from three to eight and an average litter size of four to five. 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 five or six weeks. Newly born Alaskan marmots are altricial; [22] hairless, toothless, blind [20] 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 three coats in their first year until their final one, which resembles adult Alaska marmots. [22] 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 two to three years. [20] [22] Marmots life span are not known but it is believed to be about thirteen to fifteen years. [22]
The status of Alaska marmots is not well known due to the difficulties in finding them in their natural habitat. [11] IUCN has ranked the Alaska marmot as least concern, signifying relatively low concern in terms of the dangers they face. Although Alaska marmots may be hunted, their population is stable and not at risk for endangerment. The Alaska marmot has been declared the least threatened species of marmot. [4] [1]
Although dangers of direct human disturbance are minimal, climate dangers pose a significant threat. The Alaska marmot is arguably the most sensitive of the 14 marmot species to anthropogenic disturbances, including climate change. [4]
M. broweri has been reported to have been successfully reared in captivity and reintroduced into the wild, but there have been cases where captive rearing led to high rates of mortality. [4]
Marmota broweri are sometimes hunted by Alaskan Natives for food and their warm fur. The fur is fairly valuable, worth about US$ 6 to US$8 in 1956 (equivalent to about $67.24 to $89.65 in 2023). [22] [25]
Marmot Day is a relatively new Alaskan holiday with parallels to Groundhog Day. [26] [27] Sarah Palin signed a bill in 2009 to officially make every February 2 Marmot Day. [26] 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." [26] She did not expect marmots to have any weather-forecasting duties but rather hoped that the state would create educational activities regarding the marmot. [26]
The groundhog, also known as the woodchuck, is a rodent of the family Sciuridae, belonging to the group of large ground squirrels known as marmots. The groundhog is a lowland creature of North America; it is found through much of the Eastern United States, across Canada and into Alaska. It was first scientifically described by Carl Linnaeus in 1758.
Marmots are large ground squirrels in the genus Marmota, with 15 species living in Asia, Europe, and North America. These herbivores are active during the summer, when they can often be found in groups, but are not seen during the winter, when they hibernate underground. They are the heaviest members of the squirrel family.
Ground squirrels are rodents of the squirrel family (Sciuridae) that generally live on the ground or in burrows, rather than in trees like the tree squirrels. The term is most often used for the medium-sized ground squirrels, as the larger ones are more commonly known as marmots or prairie dogs, while the smaller and less bushy-tailed ground squirrels tend to be known as chipmunks.
The hoary marmot is a species of marmot that inhabits the mountains of northwest North America. Hoary marmots live near the tree line on slopes with grasses and forbs to eat and rocky areas for cover.
The Vancouver Island marmot naturally occurs only in the high mountains of Vancouver Island, in British Columbia. This particular marmot species is large compared to some other marmots, and most other rodents. Marmots are the largest members of the Sciuridae family, with weights of adults varying from 3 to 7 kg depending on age and time of year.
The yellow-bellied marmot, 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 and semi-arid regions of southwestern Canada and western United States, including the Rocky Mountains, Sierra Nevada, and the Great Basin, often living above 2,000 metres. 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. 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.
The alpine marmot is a large ground-dwelling squirrel, from the genus of marmots. It is found in high numbers in mountainous areas of central and southern Europe, at heights between 800 and 3,200 m (2,600–10,500 ft) in the Alps, Carpathians, Tatras and Northern Apennines. In 1948 they were reintroduced with success in the Pyrenees, where the alpine marmot had disappeared at end of the Pleistocene epoch.
The Olympic marmot is a rodent in the squirrel family, Sciuridae; it occurs only in the U.S. state of Washington, on the middle elevations of the Olympic Peninsula. The closest relatives of this species are the hoary marmot and the Vancouver Island marmot. In 2009, it was declared the official endemic mammal of Washington.
The Himalayan marmot is a marmot species that inhabits alpine grasslands throughout the Himalayas and on the Tibetan Plateau. It is IUCN Red Listed as Least Concern because of its wide range and possibly large population.
The bobak marmot, also known as the steppe marmot, is a species of marmot that inhabits the steppes of Eastern Europe and Central Asia. It is a social animal and inhabits steppe grassland, including cultivated field borders. It hibernates for more than half the year. Litter sizes average about five offspring and it takes three years for the young marmots to reach sexual maturity. Male offspring leave the home colony after their second winter, and about 60% of mature females give birth in any one year.
The Arctic ground squirrel is a species of ground squirrel native to the Arctic and Subarctic of North America and Asia. People in Alaska, particularly around the Aleutians, refer to them as "parka" squirrels, most likely because their pelt is good for the ruff on parkas and for clothing.
The long-tailed marmot or golden marmot is a marmot species in the family Sciuridae. It occurs in mountainous regions in the central parts of Asia where it lives in open or lightly wooded habitats, often among rocks where dwarf junipers grow. It is IUCN Red Listed as Least Concern. As suggested by its name, it is a relatively long-tailed species of marmot.
The gray marmot, grey marmot, or Altai marmot is a species of rodent in the squirrel family Sciuridae. It is one of the larger marmots in the genus Marmota. It occurs in mountainous grasslands and shrub lands of central Asia, and is one of the 9 Palearctic (Eurasia) species. It is found in Xinjiang Province in China, southeastern Kazakhstan, Kyrgyzstan, Mongolia, and in the Altai and Tien Shan Mountains in southeastern Siberia in Russia. In the Mongolian Altai, its range overlaps with that of the Tarbagan marmot. Gray marmots form social groups, live in burrows, and hibernate.
The black-capped marmot is a species of rodent in the family Sciuridae. It is endemic to the Russian Far East, but its range is discontinuous and divided into three main parts, each with its own subspecies. The black-capped marmot lives in arctic tundra and alpine habitats from near sea-level to an altitude of 2,000 m (6,600 ft). Depending on exact subpopulation, they hibernate for 6–8 months each year, which is long for a marmot.
The Menzbier's marmot is a species of rodent in the family Sciuridae from Central Asia. Its name commemorates Russian zoologist Mikhail Aleksandrovich Menzbier.
The tarbagan marmot is a species of rodent in the family Sciuridae. It is found in China, northern and western Mongolia, and Russia. In the Mongolian Altai Mountains, its range overlaps with that of the Gray marmot. The species was classified as endangered by the IUCN in 2008.
The Alaskan hare, also known as the tundra hare, is a species of mammal in the family Leporidae. They do not dig burrows and are found in the open tundra of western Alaska and the Alaska Peninsula in the United States. They are solitary for most of the year except during mating season, when they produce a single litter of up to eight young. Predators include birds of prey and polar bears, as well as humans.
Nesting behavior refers to an instinct in animals during reproduction to prepare a place with optimal conditions for offspring. The nesting place provides protection against predators and competitors that mean to exploit or kill offspring. It also provides protection against the physical environment.
Diandrya composita is a species of cestode parasites that is known from marmots in North America. Described along with the genus Diandrya by J. G. Darrah in 1930, is known from all North American marmots except the woodchuck. This particular parasite have known to possess a combination of various organs – the interproglottidal and the pedunculated glands which were thought to be a part of the Anoplocephalidae family
The Tatra marmot is an endemic subspecies of marmot found in the Tatra Mountains. In the past, it was a game animal, but in the 19th century, its population drastically declined. It is a herbivore active in the summer, living in territorial family clans in the mountains from the upper montane to the alpine zone. It is one of the rarest vertebrates in Poland and is subject to strict legal protection. It is also legally protected in Slovakia. The Red List of Threatened Animals in Poland and the Polish Red Book of Animals classify the Tatra marmot as a strongly endangered subspecies (EN), while the Red List for the Carpathians in Poland designates it as "CR" – critically endangered. It is a relatively poorly researched animal.