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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
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
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.
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
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 )
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
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:
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
There are no known adverse affects of Alaska marmots on humans.
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
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
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
Alyaska marmotu (lat. Marmota broweri) — gəmiricilər dəstəsinin sincablar fəsiləsinə aid məməli heyvan növü.
Bu marmotların uzunluğu 53,9-65,2 sm, kütləsi 2,5-4 kq arasında dəyişir.
Alyaska marmotu Alyaskada Bruks sıra dağlarının yamaclarında yaşayır. Bu, onun yırtıcılardan qorunmasına şərait yaradır. Onlar ot, çiçəkli bitkilər, mamır və şibyə ilə qidalanırlar.
Alyaskanın yerli əhalisi alyaska marmotunun ətinin yeyir, dərisindən geyim üçün istifadə edirlər.
Moregan Alaska (Marmota broweri) a zo ur bronneg krigner hag a vev en Alaska, ha marteze e Kanada ivez.
La marmota d'Alaska (Marmota broweri) és una espècie de rosegador de la família dels esciúrids. Viu a la serralada Brooks (Alaska) i possiblement al nord-oest del Canadà. S'alimenta d'herba i plantes herboses. El seu hàbitat natural és la tundra àrtica. Hiberna durant els mesos més freds de l'any. Es creu que no hi ha cap amenaça significativa per a la supervivència d'aquesta espècie.[1]
Aquest tàxon fou anomenat en honor del caçador de balenes, paranyer, comerciant i cap de correus estatunidenc Charles Dewitt Brower.[2]
La marmota d'Alaska (Marmota broweri) és una espècie de rosegador de la família dels esciúrids. Viu a la serralada Brooks (Alaska) i possiblement al nord-oest del Canadà. S'alimenta d'herba i plantes herboses. El seu hàbitat natural és la tundra àrtica. Hiberna durant els mesos més freds de l'any. Es creu que no hi ha cap amenaça significativa per a la supervivència d'aquesta espècie.
Aquest tàxon fou anomenat en honor del caçador de balenes, paranyer, comerciant i cap de correus estatunidenc Charles Dewitt Brower.
Das Alaska-Murmeltier (Marmota broweri) ist eine sozial lebende Art aus der Gattung der Murmeltiere. Sein gesamtes Verbreitungsgebiet liegt nördlich des Polarkreises und beschränkt sich auf die Brooks Range in Alaska. Die Körperlänge dieser Murmeltierart beträgt zwischen 40 und 50 Zentimeter. Das Körpergewicht eines ausgewachsenen Tieres liegt zwischen 2,5 und vier Kilogramm. Es ist damit etwas leichter und kleiner als das ebenfalls zur arktischen Fauna gehörende sibirische Schwarzhut-Murmeltier. Verwechslungsmöglichkeiten bestehen vor allem mit dem Arktischen Ziesel, das aber etwas kleiner und leichter ist.
Diese Murmeltierart hält einen etwa neun Monate währenden Winterschlaf. Es nutzt dabei einen anderen Bau als in den Sommermonaten.
Das Alaska-Murmeltier (Marmota broweri) ist eine sozial lebende Art aus der Gattung der Murmeltiere. Sein gesamtes Verbreitungsgebiet liegt nördlich des Polarkreises und beschränkt sich auf die Brooks Range in Alaska. Die Körperlänge dieser Murmeltierart beträgt zwischen 40 und 50 Zentimeter. Das Körpergewicht eines ausgewachsenen Tieres liegt zwischen 2,5 und vier Kilogramm. Es ist damit etwas leichter und kleiner als das ebenfalls zur arktischen Fauna gehörende sibirische Schwarzhut-Murmeltier. Verwechslungsmöglichkeiten bestehen vor allem mit dem Arktischen Ziesel, das aber etwas kleiner und leichter ist.
Diese Murmeltierart hält einen etwa neun Monate währenden Winterschlaf. Es nutzt dabei einen anderen Bau als in den Sommermonaten.
De Alaskamarmot (Latynske namme: Marmota broweri) is in sûchdier út it skift fan 'e kjifdieren (Rodentia), de famylje fan 'e iikhoarntsjes (Sciuridae) en it skaai fan 'e marmotten (Marmota), dat yn syn fersprieding beheind is ta it Brooksberchtme yn it noarden fan 'e Amerikaanske steat Alaska en it noardwesten fan it Kanadeeske territoarium Yukon. It libbet dêr op berchskeanten fan tusken de 1.000 en 1.250 m hichte, dy't besteane út los pún, en fret benamme gers, blommen, beien, plantewoartels, moas, koarstmoas en út en troch ynsekten.
De Alaskamarmot hat trochinoar totale lichemslingte fan 54-65 sm en in gewicht fan 2½-4 kg. Wyfkes binne oere it generaal justjes lytser as mantsjes. By folwoeksen eksimplaren is de pels op 'e snút en de boppekant fan 'e kop ornaris dûnkerder as de rest fan it hier. De poaten kinne sawol ljocht as dûnker wêze, en binne koart en krêftich, mei lange, sterke klauwen om mei te graven. De earen binne lyts, de snút is stomp en sturt is sa tichtbehierre dat it hast wol in plomsturt liket. It netflues fan Alaskamarmotten hat hielendal gjin kegeltsjes, wat betsjut dat har nachtsicht tige min is.
Alaskamarmotten binne tige sosjale bisten, dy't yn koloanjes fan soms wol 50 eksimplaren libje yn ien ûndergrûnsk hoalestelsel. Sokke koloanjes besteane út ferskate famyljegroepen fan in mantsje en in wyfke en harren jongen út ferskillende jierren, dy't byinoar yn ien nesthoale wenje. Yn 'e gruttere koloanjes bestiet faak in komplekse rûlaasje fan it ferfoljen fan wachtpostetsjinst; sokke wachtposten warskôgje de rest fan 'e koloanje mei hege fluittoanen as der gefaar driget. De hoalen grave se yn 'e regel ûnder rotsblokken om foar te kommen dat grizzlybearen har útgrave kinne.
Alaskamarmotten hâlde in lange wintersliep, dy't fan septimber oant maaie duorret. Dêrby lizze famyljegroepen tsjininoar oan om har lichemswaarmte te dielen en sadwaande enerzjy te besparjen. Koart nei de ein fan 'e wintersliep begjint de peartiid, wêrby't de wyfkes nei in draachtiid fan likernôch 6 wiken in nêst fan 3-8 (mar ornaris 4-5) jongen smite. Oars as by in protte iikhoarntsjesoarten is it mantsje fan 'e Alaskamarmot belutsen by it grutbringen fan 'e jongen. Dy wurde keal en blyn berne en krije pas mei 6 wiken in pels. Se bliuwe teminsten ien jier by har âlden, en binne pas mei twa jier folgroeid. Geslachtsripens berikke se pas mei 2-3 jier. It is net persiis bekend hoe âld oft Alaskamarmotten wurde kinne, mar men tinkt fan sa'n 13-15 jier.
De Alaskamarmot hat de IUCN-status fan "net bedrige", hoewol't it tige dreech is om dizze soarte yn natuerlike biotoop te observearjen, sawol fanwegen de ôfhandige lokaasje as it strange klimaat. Dy lokaasje wurdt lykwols as in grut foardiel beskôge, mei't de minske de Alaskamarmot sadwaande oant no ta grutdiels gewurde litten hat. Inkeld de lânseigen Inûyt-befolking fan it gebiet makket tradysjoneel jacht op 'e bisten, mar de ynfloed dêrfan op 'e totale populaasje wurdt lyts oant ferwaarleazgber achte. Krektoarsom, de Alaskamarmot wurdt beskôge as de minst bedrige marmottesoarte fan allegear.
De Alaskamarmot (Latynske namme: Marmota broweri) is in sûchdier út it skift fan 'e kjifdieren (Rodentia), de famylje fan 'e iikhoarntsjes (Sciuridae) en it skaai fan 'e marmotten (Marmota), dat yn syn fersprieding beheind is ta it Brooksberchtme yn it noarden fan 'e Amerikaanske steat Alaska en it noardwesten fan it Kanadeeske territoarium Yukon. It libbet dêr op berchskeanten fan tusken de 1.000 en 1.250 m hichte, dy't besteane út los pún, en fret benamme gers, blommen, beien, plantewoartels, moas, koarstmoas en út en troch ynsekten.
The Alaska marmot (Marmota broweri), also known as the Brooks Range marmot[2] or the Brower's marmot,[3] 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.
Originally Marmota broweri was perceived as a synonym for M. caligata,[4][5] but this was soon proven false when evidence was found that corroborated M. broweri as a unique species.[6][7][8] Cytochrome b sequences were used to verify M. broweri as a distinct species.[8] Studies are still needed to evaluate the effects of genetic isolation on their fragmented distribution.[9]
The Alaska marmot's ancestry traces to the Pleistocene epoch.[8] There are no known fossils of Marmota broweri.[10] 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[11] has been hypothesized as being an incorrect identification of an M. broweri fossil.[10]
The evolutionary lineages of the 14 marmot species distributed across the Holarctic are relatively ambiguous.[12] Cytochrome b sequences indicated that M. broweri is most likely related to M. caudata, M. menzbieri, M. marmota, and M. monax.[12] 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.[3] In addition, somatic chromosome analysis, ecological data, and behavioral data have shown that there is a link between M. broweri and M. caligata.[8]
In terms of global distribution, the Alaska marmot is Nearctic.[10] 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.[13][10] 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.[10][14] Their overall distribution is still poorly understood.[9] 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][9]
Alaska marmots are found scattered throughout Alaska as small colonies, each consisting of several families.[15] Their locations have been documented in the Brooks Range from Lake Peters to Cape Lisburne and Cape Sabine.[16] There have been sightings of the species near rivers in the Northern Baird mountains, in the Mulik Hills,[17] near Copter Peak in the De Long Mountains,[18] and south of the Brooks Range in the Spooky Valley and in the Kokrines Hills.[10]
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[19] in Alpine tundra with herbaceous forage.[10] The species inhabits slopes surrounding lakes, and are found less commonly away from lakes.[20] Alaska marmots inhabit permanent winter dens that are used for as long as twenty years.[3] 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.[19]
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.[19] Adult Alaska marmots’ fur on their nose and the dorsal part of their head are usually of a dark color.[21] Their feet may be light or dark in color.[19] M. broweri have tough claws adapted for digging,[19] however the thumbs of their front limbs do not have these claws but flat nails instead.[21] Their body size is highly variable due to hibernation cycles.[22] For males, the average total length is 61 centimetres (24 in) and the average weight is 3.6 kilograms (7.9 lb).[2] Adult females are slightly smaller, having an average length of 58 centimetres (23 in) and 3.2 kilograms (7.1 lb).[2]
The retina of the eye of Alaska marmots is entirely lacking of rods, making their night vision quite poor.[3] Their eyes also lack a fovea, 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] Like other rodents, Alaska marmots have incisors that do not stop growing.[9] There is a single pair of incisors in each jaw.[3]
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.[19]
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.[2][3][19] M. bromeri must eat large amounts due to the low nutritional value and the need to prepare for hibernation.[2] Alaska marmots are typically known as omnivores but they have also been described as insectivorous, folivorous, frugivorous, and granivorous.[3]
The Alaska marmot is preyed on by wolverines, gray wolves, grizzly bears, coyotes, and foxes.[19] Eagles, particularly the golden eagle, are a major predator of younger marmots.[21]
A sentry marmot will alert the colony via a two-toned, high-pitched warning call if there is a predator in the area.[19] 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.[21]
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.[19]
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. Especially in large colonies, the Alaska marmots utilize sentry duty rolls that are periodically rotated.[21]
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.[8] Alaska marmots also enjoy sunbathing and spending a large amount of time in personal grooming.[3]
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.[19] Alaska marmots are active until snow begins to fall, when 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 winter hibernation period.[19] 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.[19] They then settle in their dens in family units to communally hibernate for the winter.[22]
Communal hibernation may be an adapted strategy to reduce metabolic cost while trying to keep their body temperatures above freezing.[22] 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.[21][22] Alaska marmot hibernation is not continuous because they will awaken every three or four weeks in order to urinate and defecate.[3][22] 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.[19] 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;[21] hairless, toothless, blind[19] 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.[21] 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.[19][21] Marmots life span are not known but it is believed to be about thirteen to fifteen years.[21]
The status of Alaska marmots is not well known due to the difficulties in finding them in their natural habitat.[10] 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.[3][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.[3]
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.[3]
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 $64.58 to $86.11 in 2022).[21][24]
Marmot Day is a relatively new Alaskan holiday with parallels to Groundhog Day.[25][26] Sarah Palin signed a bill in 2009 to officially make every February 2 Marmot Day.[25] 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."[25] She did not expect marmots to have any weather-forecasting duties but rather hoped that the state would create educational activities regarding the marmot.[25]
The Alaska marmot (Marmota broweri), also known as the Brooks Range marmot or the Brower's marmot, 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 Marmota generoko animalia da. Karraskarien barruko Xerinae azpifamilia eta Sciuridae familian sailkatuta dago.
Marmota broweri Marmota generoko animalia da. Karraskarien barruko Xerinae azpifamilia eta Sciuridae familian sailkatuta dago.
Marmota broweri est une espèce de mammifères de la famille des Sciuridae qui se rencontre en Alaska.
Marmota broweri a l'apparence des autres marmottes (corps trapu). Elle mesure environ 60 cm pour un poids moyen de 3,4 kg. Sa coloration générale est noirâtre[2].
Marmota broweri est une espèce de mammifères de la famille des Sciuridae qui se rencontre en Alaska.
La marmotta dell'Alaska (Marmota broweri E. R. Hall e Gilmore, 1934) è una specie della famiglia degli Sciuridi (Sciuridae) in diffusa Alaska settentrionale.
La marmotta dell'Alaska (Marmota broweri E. R. Hall e Gilmore, 1934) è una specie della famiglia degli Sciuridi (Sciuridae) in diffusa Alaska settentrionale.
De alaskamarmot (Marmota broweri) is een zoogdier uit de familie van de eekhoorns (Sciuridae). De wetenschappelijke naam van de soort werd voor het eerst geldig gepubliceerd door Hall & Gilmore in 1934.
De soort wordt aangetroffen in de Verenigde Staten.
Bronnen, noten en/of referentiesDe alaskamarmot (Marmota broweri) is een zoogdier uit de familie van de eekhoorns (Sciuridae). De wetenschappelijke naam van de soort werd voor het eerst geldig gepubliceerd door Hall & Gilmore in 1934.
Alaskamurmeldyr (Marmota broweri) er en art i gruppen murmeldyr. Den finnes i området Brooks Range i Alaska. Føden består av gress, blomster, bær, røtter, mose og lav. Lengden er mellom 54 og 65 cm. Vekten er mellom 2,5 til 4 kg.
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Denne zoologirelaterte artikkelen er foreløpig kort eller mangelfull, og du kan hjelpe Wikipedia ved å utvide den. Alaskamurmeldyr (Marmota broweri) er en art i gruppen murmeldyr. Den finnes i området Brooks Range i Alaska. Føden består av gress, blomster, bær, røtter, mose og lav. Lengden er mellom 54 og 65 cm. Vekten er mellom 2,5 til 4 kg.
Multimedia w Wikimedia Commons Świstak alaskański[3] (Marmota broweri) – gryzoń z rodziny wiewiórkowatych[4], zamieszkujący Góry Brooksa[4][5], góry Ray oraz Kokrines Hills[5] w północnej części amerykańskiego stanu Alaska[4][6], od okolic wybrzeża Morza Czukockiego do granicy z kanadyjskim terytorium Jukon. Być może zamieszkuje także w północnej części tego terytorium[4][7]. Międzynarodowa Unia Ochrony Przyrody (IUCN) wymienia świstaka alaskańskiego w Czerwonej księdze gatunków zagrożonych jako gatunek najmniejszej troski[2].
M. broweri był przez autorów pierwszego naukowego opisu (Eugene Hall i Gilmore, 1934) traktowany jako podgatunek zasiedlającego północno-zachodnie tereny kontynentu północnoamerykańskiego świstaka siwego (Marmota caligata)[7]. Dopiero w 1979 zespół naukowców[8] przedstawił dowody, że M. broweri winien być klasyfikowany jako odrębny gatunek[7].
Świstak alaskański należy do największych przedstawicieli wiewiórkowatych zamieszkujących kontynent północnoamerykański[5]. Ciało samców osiąga długość 582–652 mm (średnio 605 mm) przy masie 3–4 kg (średnio 3,6 kg)[6]. Niektóre publikacje podają opinie, że zwierzęta te mogą osiągać większe rozmiary: ponad 4,5 kg masy ciała przy długości ponad 76 cm[5]. Ciała samic są z reguły mniejsze i osiągają długość 539–599 mm (ze średnią 579 mm) przy masie 2,5–3,5 kg (ze średnią 3,2 kg)[6]. Ciało zwierząt pokryte jest stosunkowo miękkim futrem (delikatniejszym niż u zamieszkującego także tereny Alaski świstaka siwego), wybarwione jednolicie na kolor rudawobrązowy. Tułów jest gruby, głowa jest krótka, szeroka z małymi uszami. Łapy krótkie, zakończone palcami zakończonymi pazurami stanowiącymi pomocne narzędzie w kopaniu nor. Ogon jest pokryty rudawym futrem[5].
Świstaki żyją w niewielkich skupiskach w pobliżu obszarów bogatych w roślinność stanowiącą dietę tych zwierząt[6][7]. Świstak alaskański wykazuje aktywność dobową we wczesnych godzinach rannych i późnym popołudniem. Możliwe jest jednak opuszczanie nor także w innych porach dnia[5].
Okres godowy świstaków alaskańskich jest podobny jak u pozostałych gatunków świstaków zamieszkujących tereny Alaski. Zwierzęta łączą się w pary w kwietniu lub maju, a po około miesiącu rodzi się 2–6 (wg. IUCN 4–5[2]) bezwłosych i ślepych młodych. Na świat przychodzą w norze i pozostają pod opieką matki przez pierwszy rok życia. Młode świstaki osiągają dojrzałość płciową po upływie 2 lub 3 roku życia. Dożywają wieku ponad 10 lat[5].
We wrześniu dla świstaka alaskańskiego kończy się czas letniej aktywności i rozpoczyna się okres snu zimowego. Procesy metaboliczne organizmu ulegają spowolnieniu, dzięki czemu temperatura ciała ulega znacznemu obniżeniu. Hibernacja trwa do kwietnia lub maja. Zimowa nora świstaków alaskańskich jest przystosowana do długotrwałego snu zimowego. Pojedyncze wejście do tunelu wiodącego do gniazda jest lokalizowane na odsłoniętym zboczu, na którym śnieg ustępuje wczesną wiosną. Wejście zostaje jesienią zabudowywane od środka ubitą ziemią, fragmentami roślin i odchodami, tak że wszyscy członkowie klanu mogą opuścić norę dopiero na wiosnę, gdy usypana przegroda zaczyna rozmarzać[5]. Nory są stosunkowo trwałe dla każdej kolonii. Niektóre są używane przez okres ponad 20 lat[5][7].
Świstak alaskański zaznacza swoje terytorium, pocierając pysk i gruczoły o skały[5].
Świstaki alaskańskie zachowują czujność, monitorują otoczenie i sygnałami ostrzegawczymi alarmują inne świstaki przez zbliżającym się niebezpieczeństwem. W sytuacji zagrożenia – np. pojawienia się orła – świstak alaskański potrafi szybko uciekać i schować się w norze[6].
Świstaki alaskańskie zamieszkują Góry Brooksa[4][5], góry Ray oraz Kokrines Hills[5] w północnej części amerykańskiego stanu Alaska[4][6][2], od okolic wybrzeża Morza Czukockiego do granicy z kanadyjskim terytorium Jukon. Być może zamieszkują także w północnej części tego terytorium[4][2].
Świstaki alaskańskie żywią się trawami, jagodami, korzeniami, roślinami okrytonasiennymi, mchami i porostami[5]. Do drapieżników polujących na świstaki zalicza się niedźwiedzia grizli, rosomaka tundrowego, wilka kanadyjskiego, a także orła przedniego, który poluje na młode świstaki[6].
Świstaki alaskańskie zamieszkują skaliste tereny w arktycznej tundrze, na wysokości od 1000 do 1200 m n.p.m.[2]
Gatunek ten nie jest objęty ochroną i jego środowisko nie jest obecnie zagrożone[2]. Międzynarodowa Unia Ochrony Przyrody (IUCN) wymienia świstaka alaskańskiego w Czerwonej księdze gatunków zagrożonych jako gatunek najmniejszej troski[2].
Świstak alaskański (Marmota broweri) – gryzoń z rodziny wiewiórkowatych, zamieszkujący Góry Brooksa, góry Ray oraz Kokrines Hills w północnej części amerykańskiego stanu Alaska, od okolic wybrzeża Morza Czukockiego do granicy z kanadyjskim terytorium Jukon. Być może zamieszkuje także w północnej części tego terytorium. Międzynarodowa Unia Ochrony Przyrody (IUCN) wymienia świstaka alaskańskiego w Czerwonej księdze gatunków zagrożonych jako gatunek najmniejszej troski.
Marmota broweri (Marmota de Alaska) este o specie de marmotă (un mamifer săpător și hibernant din ordinul rozătoarelor / Rodentia), din familia Sciuridae, care se întâlnește în Alaska.
Marmota broweri are aparența celorlalte marmote (corp bondoc). Măsoară circa 60 cm, având o greutate medie de 3,4 kg. Colorația sa este în general negricioasă.[2]
Acest articol referitor la subiecte din zoologie este un ciot. Puteți ajuta Wikipedia prin completarea sa.
Marmota broweri (Marmota de Alaska) este o specie de marmotă (un mamifer săpător și hibernant din ordinul rozătoarelor / Rodentia), din familia Sciuridae, care se întâlnește în Alaska.
Marmota broweri[2][3][4] är en däggdjursart som ingår i släktet murmeldjur, och familjen ekorrar.[5][6] IUCN kategoriserar arten globalt som livskraftig, då Marmota broweri har en säker population och inga större hot finns.[1] Inga underarter finns listade i Catalogue of Life.[5]
Marmota broweri beskrevs första gången 1934 av Raymond Maurice Gilmore och Eugene Raymond Hall.[2] Arten ansågs länge vara samma som, eller en underart, till grått murmeldjur[1][4] men då Marmota broweri visade sig ha en annorlunda kromosomuppsättning uppstod tvivel, och skillnaden har senare bevisats genom molekylärgenetisk analys.[7] Det konstaterades även att arten är närmare släkt med asiatiska murmeldjur än de andra nordamerikanska murmeldjuren.[4][7][8]
Marmota broweri har svart och vit päls, ibland med bruna toner. Unikt för arten är den helsvarta päls som täcker ovansidan av huvudet från nos till nacke. Tänderna är liksom hos andra gnagare vassa, mejselliknande och fortsätter växa hela djurets liv. Fötterna är svarta eller svartbruna, och har fem kloförsedda tår, även om frambenens tummar har en platt nagel. Svansen är yvig och aningen platt, den utgör mellan en femtedel och en tredjedel av den totala kroppslängden.[8] Längden varierar mellan 54 och 65 centimeter. Hanarna kan bli något större än honorna och blir i snitt 60,5 cm långa medan honorna blir i snitt 58 cm långa. Vad gäller vikten är snittet 3,6 kilo för hannar respektive 3,2 kilo för honor, vikten kan variera mellan 2,5 och 4 kilogram.[8][9]
Marmota broweri återfinns i Brookskedjan i norra Alaska i USA.[1][4] Utbredningsområdet sträcker sig från Cape Lisburne i väst till Lake Peters i öst. Arten har även hittats i bergskedjan Ray Mountains och Kokrine Hills i centrala Alaska.[7] Marmota broweri lever oftast på höjder mellan 990 och 1220 meter över havet.[8]
Marmota broweri lever på den arktiska tundran, på platser där det finns större mängder klippblock, klippor, större stenar och talusar.[1] Murmeldjuren gräver sina bon mellan eller under stenarna och klippblocken. Anledningen till detta är att de behöver säkra platser för att skydda sig mot grizzlybjörnar.[1][9]
Marmota broweri är sociala djur och kan leva i kolonier på upp till 50 individer. Det finns ett direkt samband mellan hur många som lever i kolonin och hur mycket tid varje murmeldjur behöver tillbringa på vakt efter rovdjur. De turas nämligen om att stå på vakt oftast på en klippa eller en större sten i närheten av boet.[8] Om en örn cirklar runt ovanför eller ett annat rovdjur siktas i närheten, så avger djuren varningsläten och skyndar sig att gömma sig i hålorna. [9]
Arten är en av de murmeldjursarter som tillbringar längst tid i ide, mellan sex och åtta månader.[8] Marmota broweri försvinner under jord i och med de första snöstormarna i september och går i ide tills i maj eller juni.[9] Även om en grupp murmeldjur under sommaren bebor flera bon samlas gruppen under vinterdvalan i ett mer permanent bo. Detta ligger normalt på en öppen sluttning som tidigt blir snöfri. Boet har oftast bara en öppning för att minimera klimatpåverkan från utsidan, denna täpps igen en bit ifrån ytan på hösten.[8]
Marmota broweri parar sig en gång per år, oftast under tidig vår. Parningen äger rum i boet innan djuren kommer ut efter vinterdvalan, dräktigheten varar mellan fem och sex veckor.[8] En kull på fyra eller fem ungar föds under senvåren eller tidigt på sommaren. Ungarna föds i det underjordiska boet,[1] där honan stänger in sig före födseln. Både honan och hannen deltar sedan i uppfostran och beskydd av ungarna. Ungarna föds hårlösa, tandlösa och med stängda ögon, men vid ungefär sex veckors ålder har de tillräckligt mycket päls och är självständiga nog att utforska utanför boet. Unga murmeldjur lever och övervintrar med sina föräldrar i två år innan de blir fullvuxna, de blir könsmogna vid tre års ålder.[8]
Marmota broweri äter det mesta som växer i närheten av dess bon, gräs, örter, frukter, spannmål, baljväxter och ibland även insekter.[1][8] Näringsvärdet hos arktiska växter är lågt och murmeldjuren måste därför äta större mängder för att fylla sitt näringsbehov och för att förbereda sig för vinterdvala.[9]
Grizzlybjörnar brukar gräva ut murmeldjur ur sina bon, vilket är en bidragande anledning till att dessa grävs under större stenar och klippblock.[8] Utöver grizzlybjörnar jagar också järv och varg Marmota broweri, och örnar jagar unga murmeldjur.[9]
Wikimedia Commons har media som rör Marmota broweri.
Wikispecies har information om Marmota broweri.
Marmota broweri är en däggdjursart som ingår i släktet murmeldjur, och familjen ekorrar. IUCN kategoriserar arten globalt som livskraftig, då Marmota broweri har en säker population och inga större hot finns. Inga underarter finns listade i Catalogue of Life.
Alaska marmotu (Marmota broweri), sincapgiller familyasının yer sincapları oymağından, Alaska'da Brooks Sıradağlarında yaşayan marmot türü. Besini otlar, çiçekli bitkiler, meyveler, kökler, yosunlar ve likenlerdir[1]. Boyu 54–65 cm, ağırlığı ise 2,5–4 kg gelir[2]. Alaska'da her yıl 2 Şubatta kutlanan Marmot Günü etkinliğinde adı geçen hayvandır ve bu etkiblik 18 Nisan 2009 tarihinden itibaren resmi tatil günlerinden biridir[3].
Kış uykusuna sekiz ay yatar ve bu uykuya en uzun süre yatan marmotlardan biridir[4].
Alaska marmotunun alt cinsi Marmota olup eskiden Petromarmota alt cinsinden Marmota caligata türünün alt türü olarak sınıflandırılırdı[5][6][7][8][9] Cytochrome b dizileri M. broweri türünün ayrı olduğunu ortaya koyar[9].
Alaska marmotu nearktik türdür[2]. Ana yayılım alanı Brooks Sıradağları, Ray Dağları ve Kokrines Hills tepeleridir[10]. Orta ve Kuzey Alaska'da Yukon Nehrinin ve Porcupine Nehrinin kuzeyindeki dağlarda da görülür[2]. Bunula birlikte, Kanada'nın Yukon eyaletindeki Richardson Dağlarında görüldüğüne dair raporlar henüz teyid edilmemiştir[2][11].
Alaska marmotu Kutup porsuğu, boz kurt, Kuzey Amerika boz ayısı ve kaya kartalı (genç marmotların ana avcısıdır) tarafından avlanır[1].
İnyupikler siksrikpak (harfiyen: «büyük Arktika gelengisi») adını verdikleri Alaska marmotunu kürkü için avlarlar. Yaklaşık 20 marmottan bir parka (atigi) yapılır[12].
|erişim-tarihi= kullanmak için |url= gerekiyor (yardım) |erişim-tarihi= kullanmak için |url= gerekiyor (yardım) |erişim-tarihi= kullanmak için |url= gerekiyor (yardım) |erişim-tarihi= kullanmak için |url= gerekiyor (yardım) Alaska marmotu (Marmota broweri), sincapgiller familyasının yer sincapları oymağından, Alaska'da Brooks Sıradağlarında yaşayan marmot türü. Besini otlar, çiçekli bitkiler, meyveler, kökler, yosunlar ve likenlerdir. Boyu 54–65 cm, ağırlığı ise 2,5–4 kg gelir. Alaska'da her yıl 2 Şubatta kutlanan Marmot Günü etkinliğinde adı geçen hayvandır ve bu etkiblik 18 Nisan 2009 tarihinden itibaren resmi tatil günlerinden biridir.
Kış uykusuna sekiz ay yatar ve bu uykuya en uzun süre yatan marmotlardan biridir.
Macmot Alaska, tên khoa học Marmota broweri, là một loài động vật có vú trong họ Sóc, bộ Gặm nhấm. Loài này được Hall & Gilmore mô tả năm 1934.[2]
Macmot Alaska, tên khoa học Marmota broweri, là một loài động vật có vú trong họ Sóc, bộ Gặm nhấm. Loài này được Hall & Gilmore mô tả năm 1934.
알래스카마멋(Marmota broweri)은 다람쥐과에 속하는 설치류의 일종이다. 브룩스산맥마멋[2] 또는 브로워마멋[3]으로도 불린다. 알래스카주 브룩스 산맥 경사면의 무너져 내린 바위 부스러기 지역에서 발견된다. 풀과 속씨식물, 열매, 뿌리, 이끼, 지의류 등을 먹는다.[2] 몸길이 범위는 약 54~65cm이고, 몸무게는 2.5~4kg이다. 알래스카는 매년 2월 2일을 마멋이 굴에서 나오는 것을 통해 겨울이 얼마나 남아 있는가를 점치는 그라운드호그 데이를 대신하는 "마멋의 날"을 휴일로 기념한다.[4]
다음은 2009년 헬겐(Helgen) 등의 연구에 기초한 계통 분류이다.[5]
마멋족 마멋속
