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Marmots are a social animal that communicate with one another through direct contact and whistling vocalizations. Vancouver Island marmots have an array of calls that are used to communicate potential danger to conspecifics. When a marmot produces a call, other marmots within the area become vigilant toward the threat. As with other marmot species, calls can be flat, trilled, and ascending or descending in tone; however this species has a characteristic "kee-aw" call not used by other marmots. Calls are not specific to terrestrial or aerial predators, though flat calls are more frequently used with terrestrial predators. Kee-aws are used when the threat is not intense or imminent, though it induces maintained vigilance in conspecifics. Trills are used most frequently during high threat interactions. Females with weaning pups are more likely to emit calls than other marmots, presumably to increase the vigilance of their offspring and relatives.
Vancouver Island marmots mark territories with scent glands located in their cheeks. The majority of scent marking is done by adult males, though adult females also scent mark.
Communication Channels: visual ; tactile ; acoustic
Other Communication Modes: pheromones ; scent marks
Perception Channels: visual ; tactile ; acoustic ; chemical
Additional information regarding reintroduction programs can be found at www.marmots.org.
First listed as endangered in 1978 and now critically endangered, Vancouver Island marmots are currently one of the rarest animals in North America. In 2004, it was estimated that only 35 individuals remained in the wild in an area less than 10 km². While these marmots have historically lived at low densities as a result of limited habitat and predation pressures, the recent sharp decline in numbers has been attributed to habitat loss from clear cut logging. While a temporary increase in population occurred as a result of logging in the 1980s - newly clear cut landscapes create ideal forage, burrow sites and visibility for marmots, - colonies that established in these areas vanished after a few years. Reforestation of these areas provided excellent cover for predators, and overwintering success was low. The population peaked at 300 to 350 marmots in 1984 before a drastic decline as a result of high mortality rates.
As opposed to even mortality across populations, it appears that entire colonies fail at one time, a trend consistent with intense predation, disease and poor hibernacula. Prior to reintroduction efforts, the population of Vancouver Island marmots declined more than 80% in 20 years, and extinction in the wild was imminent.
In 1998, the Marmot Recovery Foundation was established and 4 breeding programs were organized across Canada in an effort to reintroduce Vancouver Island marmots to the wild: the Calgary and Toronto zoos, Mountain View Conservation and Breeding Centre in Langley, BC and the Tony Barrett Mt Washington Marmot Recovery Centre on Vancouver Island. As of 2010, the program has been a success, with the wild population estimated to be about 300 individuals. Vancouver Island marmots now inhabit 27 mountains, compared with the 5 that were inhabited in 2003. The Recovery Strategy Goal is to have 600 marmots living in the wild in core populations in south, central and northern Vancouver Island.
Captive born individuals have successfully established colonies, surviving through the winter and producing pups. The second generation of pups from captive born marmots have successfully weaned in the wild. It is thought that several more years and a greater understanding of this species' ecology and behaviour is necessary to reach sustainable populations in the wild. Further conservation sites at marmot colonies are also sought after by the Marmot Recovery Foundation, which hopes to establish Wildlife Habitat Areas at colonization and reintroduction sites.
US Federal List: endangered
CITES: no special status
IUCN Red List of Threatened Species: critically endangered
There are no known adverse affects of Vancouver Island marmots on humans, as they live in remote areas at extremely low densities.
The role of Vancouver Island marmots as prey for wolves and cougar may allow for higher populations of these fur bearing animals.
As herbivores, Vancouver Island marmots may act as seed dispersers and pollinators for the variety of grasses and flowers that they consume; as they amble about subalpine meadows to forage, they may collect various pollens and disperse consumed seeds through their feces. Further, they build large burrow systems that may be used by other animals, including insects and small mammals.
Vancouver Island marmots are hosts to ticks (Ixodes) and fleas (Thrassis spenceri). Many trapped marmots are heavily infested, though parasite infestation does not seem to decrease their survival or fecundity. Vancouver Island marmots also act as hosts for the nematode Baylisascaris laevis. Interestingly, the cestode Diandrya vancouverensis is completely unique to Vancouver Island marmots. This tape worm is closely related to a mainland helminth found in Marmota olympus and may be an example of coevolution due to allopatric speciation.
The increase in predation and consequent decrease in marmot populations is believed to be an indirect result of a decrease in black-tailed deer (Odocoileus hemionus columbianus), the main prey of wolves and cougars. The small deer population has caused an increase in both wolf and cougar predation upon alternative food sources, which includes Vancouver Island marmots.
Ecosystem Impact: disperses seeds; pollinates; creates habitat; soil aeration
Commensal/Parasitic Species:
Vancouver Island marmots eat primarily grass and forbs that are found in subalpine meadows. They forage slowly across their home range, preferentially eating flowers, fruits and fresh buds. They also browse on fresh fiddleheads of bracken fern (Pteridium aquilinum). In the spring, grasses make up the majority of the diet, including oatgrass (Danthonia intermedia), woodrush (Luzula) and various sedges (Carex). Spreading phlox (Phlox diffusa) and lupine herbs (Lupinus) are consumed readily when present but are not as common as grasses at this time of year. Throughout the summer, meadowrue (Thalictrum), paintbrush (Haemanthus), cow parsnip (Heracleum maximum) and woolly sunflower (Eriophyllum lanatum) are consumed. By late summer, broad leaved herbs such as peavine (Lathyrus) and lupines make up the majority of the diet. Foraging occurs most often in the early morning and evening.
Plant Foods: leaves; fruit; flowers
Primary Diet: herbivore (Folivore , Frugivore )
Vancouver Island marmots are found on south and west facing mountain ridges that are free of trees as a result of avalanches and snow accumulation during the winter months. Steep tree-less slopes allow for rapid snow melt in the spring, good visibility of predators, and excellent areas in which to "lounge" in order to thermoregulate. Vancouver Island marmots also inhabit mine tailings and meadows created by ski runs. They are found at at high elevations, from 900 to 1450 m above sea level.
Although rare, some marmots have been recorded at low elevations in suburban areas, such as back yards and in one case on a private dock. In general, the high amount of brush and trees makes lower elevations unsuitable habitat, and intensely forested landscapes do not contain the forbs and grasses necessary to the diet of Vancouver Island marmots.
Vancouver Island marmots require colluvial soil structure for their burrows, which are used to escape predators, overwinter and hibernate. Vancouver Island marmots require deep soil, as they burrow below the frost line during winter; winter temperatures within the hibernacula must be maintained at at least 5 °C. Higher elevations typically do not contain soil patches deep enough to construct proper burrows, while lower elevations are too heavily vegetated and warm. Burrows may be found at the base of tree trunks and large boulders where visibility is good. For this reason, newly clear-cut areas may be quickly colonized but do not support long term populations as a result of poor overwintering success and forest regeneration. Populations of Vancouver Island marmot are limited primarily by the availability of suitable habitat.
Range elevation: 900 to 1500 m.
Habitat Regions: temperate ; terrestrial
Terrestrial Biomes: savanna or grassland ; mountains
Vancouver Island marmots, Marmota vancouverensis, are endemic to Canada. They are found only on Vancouver Island, located in the south-western portion of Canada. Through extensive captive breeding and reintroduction programs, this species is now re-established on 27 mountains in south, central and northern Vancouver Island.
Biogeographic Regions: nearctic (Native )
Other Geographic Terms: island endemic
Vancouver Island marmots have an average lifespan of 10 years, with females typically living longer than males. Based on longevity of closely related marmot species, the maximum age of Vancouver Island marmots is estimated to be between 12 and 15 years. Average age of mortality due to predation is around 3 years, with the majority of these deaths occurring from August to September. The majority of pup mortality occurs over the first winter during hibernation. Annual survival rate of Vancouver Island marmots is 73%.
Average lifespan
Status: wild: 10 years.
Range lifespan
Status: captivity: 12.1 (high) years.
Vancouver Island marmots are semi-fossorial sciurids that differ from other marmots in their pelage coloration. Adults are a dark chocolate brown color and have characteristic irregular patches of white fur on their chest, chin, nose and forehead. Other closely related marmot species (hoary marmots Marmota ciligata and Olympic marmots Marmota olympus) are tawny or grey colored, with no distinct white markings. The dorsal side of Vancouver Island marmots have white hairs interspersed, but with no prominent patterning.
Pups are born a uniform black-brown that fades to a reddish brown in the summer months. As this species does not complete a full molt every year, juveniles are easily identifiable by their mottled rust colour when compared to the darker, white marked adults. Molting occurs unevenly, beginning on the forelegs and shoulders and ending with the head, back and tail.
Mature Vancouver Island marmots measure between 56 and 70 cm from the nose to the tip of the tail. Their tails are bushy and covered with relatively coarse, long guard hairs. Their body is stout with short strong legs, and paws are pentadactyl, donned with robust fossorial claws for burrowing. Forepaws have two posterior pads and three anterior pads located at the base of the digits, while hind paws have two posterior pads and four anterior pads at the base of the digits. Posterior foot pads are circular, a trait that is shared with the closely related M. caligata and Marmota olympus. The head is broad and short, with relatively short ears located dorsolaterally, slightly posterior to the eyes. Adults weigh between 3 and 7 kg depending on sex and time of year. Males tend to weigh significantly more than females. Vancouver Island marmots weigh the most in mid-September, prior to hibernation.
Skull structure of Vancouver Island marmots is one of the strongest distinguishing feature of this species. The nasals are shorter than those found in other marmot species (41.5 mm +/- 0.7 mm) and have a v-shaped notch at the posterior border. Parietal bones are relatively narrow when compared with other Marmota sp., and the coronoid process has a distinct bend at its tip. Average condylobasal length is reported as 92.7 mm =/- 0.7 mm, with average width of rostrum of 21.8 mm +/- 0.3 mm, zygomatic width 60.7 mm +/- 0.6 mm, and interorbital width of 22.3 mm +/- 0.4 mm (n = 10 for all measurements). Average male cranial measurements are larger than females. Dental formula for the Vancouver Island Marmot is 1/1, 0/0, 2/2, 3/3 = 24. Incisors are prominent and typically pale to dark yellow on the labial side and lighter on the lingual side.
Range mass: 3 to 7 kg.
Range length: 65 to 70 cm.
Sexual Dimorphism: male larger
Other Physical Features: endothermic ; bilateral symmetry
Vancouver Island marmots are subject to strong predation pressure, with 83% of annual mortality resulting from predation. Death due to wolves account for 38%, cougars 21%, and golden eagles 14%. While no incidents have been recorded, it is likely that bald eagles occasionally prey upon marmots. Predators target adult marmots, and the majority of predation occurs in late summer, between August and September.
Between 1992 and 2007, the overall annual survival of adults marmots was 70.9%. This is much lower than then 80% survival rate necessary to sustain populations, indicating a steady decline. Survival rates of both adults and pups does not differ with age and sex.
The increase in home range size over the last 30 years likely makes these marmots more vulnerable to predation.
When a predator approaches, Vancouver Island marmots become vigilant and orient their body toward the threat at a distance of 50 m. Prior to emitting an alarm call, they retreat to locations near burrow entrances when the perceived threat is approximately 32 m away. A variety of alarm calls warn conspecifics of the threat.
Known Predators:
Small colonies consist of a single family group containing 1 male, 1 to 2 females, juveniles and young of the year. Vancouver Island marmots have a monogamous mating system, though males have been recording siring more than one litter in a single breeding season. Pairs breed for multiple years, with juveniles dispersing from the family colony between 2 and 3 years of age. Younger males are subordinate to older males, with females preferentially breeding with males 3 years of age or older. As females tend to live longer than males, the operational sex ratio is skewed toward older females.
As with many mammals, behavior associated with reproduction in Vancouver Island marmots corresponds with increased levels of reproductive hormones such as estrogen and progesterone in females and testosterone in males. Ovulation is induced through copulation, and an increase in play behaviour corresponds to frequent copulation; several attempts may be necessary for conception to occur. Because mating occurs within burrows, little is known regarding specific mating behaviors.
In captivity, female Vancouver Island marmots are more receptive to males they have had prolonged contact with, suggesting that the strength of the social system is integral in mating success. The relatively large distances between colonies (20 km^2) that has occurred as a result of recent population declines may be negatively impacting reproductive success due to a lack of access to potential mates.
Mating System: monogamous ; polygynous
Female Vancouver Island marmots reach reproductive maturity between the ages of 2 and 4. Females rarely raise pups at the age of 2, and most often raise their first litter of pups between the ages of 4 and 5. Mating occurs once a year in the early spring when snow melts and adults emerge from hibernation. While mating is seasonal, individual females rear young every 1 to 3 years. Females may give birth for the first time between the ages of 2 to 6. While males younger than 3 may be sexually mature, they rarely mate as they are subordinate to older males.
Vancouver Island marmots usually have litters of 3 to 4 pups, though litter size can range from 1 to 7. Litter size and success varies greatly from year to year, perhaps depending on food availability, female body condition, and weather. Past rearing of pups does not appear to influence survival of offspring. Females in the intermediate age class have a higher rate of reproductive success than young or old individuals, and older females also produce fewer offspring. Gestation lasts approximately 32 days, and pups are weaned at about 30 days of age. Weaning tends to occur at the beginning of July, when pups emerge from the burrows.
Breeding interval: Vancouver Island marmots breed every 1 to 3 years.
Breeding season: Vancouver Island marmots breed in the spring from early May to June.
Range number of offspring: 1 to 7.
Average number of offspring: 3.6.
Average gestation period: 32 days.
Average weaning age: 30 days.
Average age at sexual or reproductive maturity (female): 3 years.
Average age at sexual or reproductive maturity (male): 3 years.
Key Reproductive Features: seasonal breeding ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; induced ovulation ; viviparous
Average gestation period: 30 days.
Average number of offspring: 3.3.
Average age at sexual or reproductive maturity (female)
Sex: female: 1186 days.
Parturition of Vancouver Island marmots occurs within burrow chambers in late May to early June. Pups remain underground where the mother nurses, emerging to forage. Males do not appear to play a direct role in care of the offspring, but do provide protection through vigilance to potential threats. Pups are weaned at about 30 days of age.
Vancouver Island marmot young of the year first emerge from their burrows in late June or early July. They remain near the natal burrow for their first year and often hibernate in the same burrow system as their mother. Pup mortality is generally low until hibernation, with the majority of mortality occurring over the winter. Females with young have significantly smaller home ranges than females who did not breed that year, indicating increased vigilance and preparedness to retreat to burrow systems. Adults with pups experience an increased risk of predation compared to adults that are without pups in the same breeding season.
Parental Investment: altricial ; female parental care ; pre-hatching/birth (Provisioning: Female, Protecting: Female); pre-weaning/fledging (Protecting: Male, Female); pre-independence (Provisioning: Female); post-independence association with parents; inherits maternal/paternal territory
Vankuver marmotu (lat. Marmota vancouverensis) — gəmiricilər dəstəsinin sincablar fəsiləsinə aid məməli heyvan növü. Şimali Amerika gəmiricisi olan bu məməli heyvan Kanadanın Vankuver adası üçün endemikdir və əsasən adanın cənub hissələrində hündürlüyü 500 m-ə qədər olan dağlarda yaşayır. Bu marmotlar ayrıca növ olub nəsli kəsilmək təhlükəsi ilə üz-üzədir. Belə ki, təbii şəraitdə yaşayan cəmi 35-dən az növün qaldığı təsbit edilmişdir.
Vankuver marmotunun xəzi fəsillərə görə müxtəlif rəngdə olur. Yayın əvvəlində qəhvəyi, iyulda isə xəz tökülür və bədənin və başın yuxarı hissəsində ağ zolaqları olan qara rəngdə olur. Marmotun kütləsi də fəsillərə görə dəyişir və il ərzində 3-3,5 kq-la 5-6 kq arasında dəyişir. Bədəninin uzunluğu 68-70 sm olur.
La marmota de l'illa de Vancouver (Marmota vancouverensis) és una espècie de rosegador esciüromorf de la família Sciuridae endèmica de les terres més altes de l'illa de Vancouver (Canadà), fàcilment diferenciable d'altres marmotes pel seu llarg i espès pelaje de color marró fosc, esquitxat de taques blanques. En l'actualitat només existeixen al voltant d'un centenar d'individus, la qual cosa converteix a aquesta marmota en un dels mamífers més rars. La població actual és el resultat d'una política de cria en captivitat que ha aconseguit triplicar els 30 exemplars salvatges que sobrevivien el 2003. El seu parent més proper és la marmota monax del nord-oest de Nord-amèrica.
Vancouvermurmeldyr (latin: Marmota vancouverensis) er en art af murmeldyr, som udelukkende forekommer naturligt i bjergene på Vancouver Island, British Columbia i Canada. Det er en af de største murmeldyrarter og gnavere i det hele taget, og de voksne individer kan veje mellem 3 og 7 kg, afhængig af årstid og alder.
Skønt arten er endemisk på Vancouver Island, har man haft held til at avle vancouvermurmeldyret på forskellige avslcentre i Canada, herunder også på Vancouver Island, hvor arten i visse områder var tæt på at uddø i 1990'erne.[1] Avlsprogrammet er et forsøg på at forhindre arten i at uddø fuldstændig og genskabe en bæredygtig population af dette unikt canadiske murmeldyr.[2]
Vancouvermurmeldyr (latin: Marmota vancouverensis) er en art af murmeldyr, som udelukkende forekommer naturligt i bjergene på Vancouver Island, British Columbia i Canada. Det er en af de største murmeldyrarter og gnavere i det hele taget, og de voksne individer kan veje mellem 3 og 7 kg, afhængig af årstid og alder.
Skønt arten er endemisk på Vancouver Island, har man haft held til at avle vancouvermurmeldyret på forskellige avslcentre i Canada, herunder også på Vancouver Island, hvor arten i visse områder var tæt på at uddø i 1990'erne. Avlsprogrammet er et forsøg på at forhindre arten i at uddø fuldstændig og genskabe en bæredygtig population af dette unikt canadiske murmeldyr.
Das Vancouver-Murmeltier (Marmota vancouverensis) ist eine Art aus der Familie der Hörnchen, das lediglich auf Vancouver Island beheimatet ist. Innerhalb der Gattung der Murmeltiere gilt das Vancouver-Murmeltier als die am ehesten durch Aussterben bedrohte Art. Bestandsgefährdend wirken sich auf diese Art Habitatverluste sowie eine genetische Verarmung aus. Zu massiven Bestandseinbrüchen kam es vor allem in den 1990er Jahren, was dazu führte, dass ein intensives Programm zur Erhaltung dieser Art in die Wege geleitet wurde. Dazu gehören ein Zuchtprogramm mit in Gefangenschaft gehaltenen Tieren und die Wiedereinführung von erhaltungsfähigen Populationszahlen in geeigneten Gebieten.
Das Vancouver-Murmeltier zählt zu den größten Vertretern innerhalb der Gattung der Murmeltiere. Das Gewicht der Tiere schwankt sehr stark in Abhängigkeit von der Jahreszeit. Im September, kurz vor Beginn des Winterschlafes, wiegen sie bis zu 6 Kilogramm. Nach Beendigung des Winterschlafes beträgt ihr Körpergewicht häufig nur noch drei Kilogramm.
Die Fellfarbe des Vancouver-Murmeltieres ist überwiegend ein dunkles schokoladenbraun. An der Körperunterseite sowie um die Schnauze finden sich vereinzelte weiße Stellen. Auch auf der Stirnseite des Kopfes gibt es vereinzelte weiße Fellpartien.
Neben diesen weißer Scheckung weist das Vancouver-Murmeltier auch vereinzelt hellbraune oder ockerfarbene Stellen auf.
Vancouver-Murmeltiere sind in ihrer Verbreitung auf die vor der kanadischen Westküste liegende Vancouver Island beschränkt. Diese Insel ist mit 32.000 Quadratkilometern die größte Insel vor der Westküste Nordamerikas. Die Insel weist eine sehr gebirgige Struktur auf. Die höchsten Erhebungen liegen bei 2200 m. Kolonien des Vancouver-Murmeltieres fanden sich entlang der gesamten, vom Nordwesten nach Südosten verlaufenden Gebirgskette. Das heute besiedelte Gebiet ist wesentlich kleiner. Es gibt eine isolierte Kolonie am Mount Washington sowie ein 150 Quadratkilometer großes, südöstlich von Mount McQuillan und Mount Arrowsmith liegendes Gebiet, in der noch mehrere Kolonien existieren[1].
Vancouver-Murmeltiere besiedeln bevorzugt südlich oder westlich ausgerichtete Gebirgshänge und präferieren dabei Höhenlagen zwischen 1000 und 1400 Meter[2]. Bedingt durch regelmäßige Lawinenabgänge kommt hier kein Baum oder Strauchbewuchs auf. Erst dadurch entstehen für die Murmeltiere die notwendigen baumlosen Wiesen, auf denen sie ausreichend Äsung finden.
In der Mitte der 1980er Jahre wurde die Anzahl der noch in freier Wildbahn vorkommenden Vancouver-Murmeltiere auf etwa 350 Individuen geschätzt. Bei einer erneuten Zählung im Jahre 1998 wurden insgesamt 71 Vancouver-Murmeltiere gezählt und der Gesamtbestand auf 85 bis 95 geschätzt. Von insgesamt 25 bekannten Kolonien kommen nur in 13 noch Jungtiere zur Welt[3]. Die Art gilt daher als extrem bedroht. Als Ursache des Bestandseinflusses gilt vor allem Habitatverlust infolge von Holzeinschlag sowie Auswirkungen von Klimaschwankungen.
Die Murmeltiere scheinen zunächst vom Holzeinschlag zu profitieren. Von bestehenden Kolonien aus begründen abwandernde Jungtiere neue Kolonien in diesen Regionen. Diese Kolonien scheitern jedoch innerhalb weniger Jahre, wenn Lawinenabgänge fehlen und rasch eine dichte Vegetation entsteht, in der bereits die ersten Bäume wieder hochkommen. Die Murmeltiere finden in diesen Gebieten nicht die geeigneten Nahrungspflanzen, mit deren Hilfe sie ausreichend Fettreserven anlegen können, um die Zeit des Winterschlafes zu überstehen. Vom Alpenmurmeltier weiß man, dass sie im Sommer, wenn ihnen ein reichhaltiges Nahrungsangebot zur Verfügung steht, bevorzugt die jungen Triebe solcher Pflanzen fressen, die besonders reich an mehrfach ungesättigter Fettsäure sind. Diese Inhaltsstoffe können vom Säugetierorganismus nicht selbständig generiert werden. Eine hohe Konzentration von essentiellen Fettsäuren im weißen Fettgewebe von Winterschläfern befähigt diese aber, während des Winterschlafes auch tiefere Körpertemperaturen zu tolerieren[4]. Beim Fehlen geeigneter Nahrungspflanzen steigt für Murmeltiere das Risiko, dass sie das Winterhalbjahr wegen eines Mangels an wärmenden Fettreserven nicht überleben. Je geringer die Fettreserven sind, desto geringer ist auch die Wahrscheinlichkeit, dass die Weibchen im nächsten Jahr Jungtiere austragen werden. Diese zwei Wirkmechanismen sorgen sehr schnell dafür, dass Kolonien in nicht geeigneten Lebensräumen wieder erlöschen.
Als weitere Ursache für einen Bestandsrückgang wird diskutiert, dass infolge ansteigender Jahresdurchschnittstemperaturen die Vegetation auf Vancouver Island sich so verändert, dass die Tiere nicht mehr ausreichend Pflanzen jener Arten finden, die für den Aufbau der Fettreserven nötig sind.[5]
Das Vancouver-Murmeltier ist eng verwandt mit dem Olympmurmeltier (M. olympus) sowie dem Eisgrauen Murmeltier (M. caligata). Das Verbreitungsgebiet des Olympmurmeltieres ist die Olympic Peninsula südlich von Vancouver Island. Das Eisgraue Murmeltier dagegen ist in nordamerikanischen Hochgebirgsregionen beheimatet. Es ist eine relativ junge Art, die möglicherweise erst während der letzten Eiszeit entstand, als Eisbarrieren einen Individuenaustausch verhinderten.
In den letzten Jahren sind unterschiedliche Maßnahmen ergriffen worden, damit das Vancouver-Murmeltier als Art weiterhin besteht. Zu den Maßnahmen zählt die Gefangenschaftshaltung in den Zoos von Toronto und Calgary. Nachzuchten in Zoos sollen sicherstellen, dass eine ausreichende Anzahl von Tieren zur Verfügung stehen, um gegebenenfalls für Wiederansiedelungsprogramme eine ausreichende Anzahl von Tieren zur Verfügung zu haben.
Auf Vancouver Island wird versucht, innerhalb eines unter Schutz stehenden Gebietes die Anzahl der dort lebenden Tiere zu erhöhen und zu stabilisieren. Sowohl bei der Nachzucht in Gefangenschaft als auch bei den beobachteten Kolonien in Freiland soll sichergestellt werden, dass es nicht zu Inzuchtdepressionen kommt. Genetische Untersuchungen haben bewiesen, dass die Zahl der Allele sowie der Heterozygotiegrad beim Vancouver-Murmeltier im Vergleich zum Alpenmurmeltier deutlich geringer ist[6]. Neben dem Mangel an geeigneten Habitaten stellt die Verarmung des Genpools eine weitere Bedrohung für diese Art dar.
Eines der Maskottchen der Olympischen Winterspiele 2010, Mukmuk, stellt ein Vancouver-Murmeltier dar.[7]
Das Vancouver-Murmeltier (Marmota vancouverensis) ist eine Art aus der Familie der Hörnchen, das lediglich auf Vancouver Island beheimatet ist. Innerhalb der Gattung der Murmeltiere gilt das Vancouver-Murmeltier als die am ehesten durch Aussterben bedrohte Art. Bestandsgefährdend wirken sich auf diese Art Habitatverluste sowie eine genetische Verarmung aus. Zu massiven Bestandseinbrüchen kam es vor allem in den 1990er Jahren, was dazu führte, dass ein intensives Programm zur Erhaltung dieser Art in die Wege geleitet wurde. Dazu gehören ein Zuchtprogramm mit in Gefangenschaft gehaltenen Tieren und die Wiedereinführung von erhaltungsfähigen Populationszahlen in geeigneten Gebieten.
S Vancouver-Murmeli (Marmota vancouverensis) isch e Hörnli-Art, wo nume uf de Insle Vancouver vorchunnt.
Für Nagedier si d Vancouver-Murmeli ehnder gross: Si hai je noch dr Art e Chopf-Rumpf-Lengi vo 30 bis 60 Santimeter, drzue chunnt e 10 bis 25 Santimeter lange Schwanz. S Gwicht lit zwüsche drei und siibe Kilogramm. D Farb vom Fäll underscheidet sich vo Art zu Art, isch aber meistens e Bruundon; s Vancouver-Murmeldier isch eifarbig schwarz. Murmeldier wärde bis zu 15 Johr alt.
S Vancouver-Murmeli (Marmota vancouverensis) isch e Hörnli-Art, wo nume uf de Insle Vancouver vorchunnt.
Für Nagedier si d Vancouver-Murmeli ehnder gross: Si hai je noch dr Art e Chopf-Rumpf-Lengi vo 30 bis 60 Santimeter, drzue chunnt e 10 bis 25 Santimeter lange Schwanz. S Gwicht lit zwüsche drei und siibe Kilogramm. D Farb vom Fäll underscheidet sich vo Art zu Art, isch aber meistens e Bruundon; s Vancouver-Murmeldier isch eifarbig schwarz. Murmeldier wärde bis zu 15 Johr alt.
De Vancouvereilânmarmot (Latynske namme: Marmota vancouverensis) is in sûchdier út it skift fan 'e kjifdieren (Rodentia), de famylje fan 'e iikhoarntsjes (Sciuridae) en it skaai fan 'e marmotten (Marmota), dat fan natuere inkeld foarkomt op Vancouvereilân, foar de súdwestkust fan Kanada. Dizze soarte is oan 'e grutte kant foar in marmot, en is nau besibbe oan 'e Olympyske marmot en de grize marmot, dy't deunby op dielen fan it fêstelân fan Noard-Amearika foarkomme. De Vancouvereilânmarmot is slim yn syn fuortbestean bedrige, dat der is no in fokprogramma foar eksimplaren yn finzenskip opset om him fan it útstjerren te rêden.
It ferspriedingsgebiet fan 'e Vancouvereilânmarmot is fan natuere beheind ta Vancouvereilân, in grut eilân dat yn 'e Stille Oseaan leit, deun foar de Kanadeeske súdwestkust, en diel útmakket fan 'e provinsje Britsk-Kolumbia. It is de iennichste marmottesoarte dy't op Vancouvereilân foarkomt, dêr't er bedarre wêze moat yn 'e lêste iistiid yn Noard-Amearika, sa'n 10.000 jier lyn, doe't it eilân mei it fêstelân yn ferbining stie. Biologen ornearje dat de marmot him yn isolaasje op it eilân fluch ûntwikkele hawwe moat, mei't er tsjintwurdich dúdlik fan besibbe soarten ôfwykt op it mêd fan morfology, genetika, hâlden en dragen en ekology. De measte Vancouvereilânmarmotten libje op 'e westlike kant fan berchskeanten, boppe de 1.000 m hichte.
De Vancouvereilânmarmot hat trochinoar in totale lichemslingte fan 65-70 sm, mei in gewicht dat útinoar rinne kin fan 3 kg oan 'e ein fan 'e wintersliep oant 4½-7 kg oan 'e ein fan 'e simmer. Dêrmei is er likernôch sa grut as in út 'e kluten woeksen hûskat. De pels hat in rike, sûkelarjebrune kleur mei dúdlik kontrastearjende wite plakken, û.m. op 'e snút.
Vancouvereilânmarmotten binne herbivoaren, dy't foar it meastepart fan gerzen en krûden libje. Se lizze ûndergrûnske hoalen oan, wêryn't se fan ein septimber of begjin oktober oant ein april of begjin maaie har wintersliep trochbringe. De lingte fan 'e wintersliep hat te krijen mei it plak (hichte boppe seenivo) fan har hoale en mei de waarsomstannichheden fan dat jier. Trochinoar duorret har wintersliep 210 dagen, mar yn finzenskip is dat in stik koarter. De peartiid begjint foar de Vancouvereilânmarmot koart nei de ein fan 'e wintersliep. Nei in draachtiid fan 30-35 dagen smyt it wyfke dan in nêst fan 3-4 jongen, dy't har oer it algemien begjin july foar it earst bûten de hoale weagje. Vancouvereilânmarmotten binne mei twa jier geslachtsryp, mar nimme almeast pas mei trije of fjouwer jier oan 'e fuortplanting diel.
De Vancouvereilânmarmot hat de IUCN-status fan "krityk", wat sizze wol dat er op it rântsje fan it útstjerren balansearret. De soarte is fral yn 'e tweintichste iuw dramatysk efterútbuorke as direkt gefolch fan klimaatferoaring en as yndirekt gefolch fan minsklik yngripen. Saakkundigen riddenearje no sa: de marmotten libje yn in berchgreide-habitat dat op Vancouvereilân mar krap te finen is. Jongen ferlitte nei ferrin fan tiid it territoarium fan har âlden op 'e siik nei in gaadlik plak om harsels nei wenjen te setten. Dêrfoar geane se omleech út 'e berchgreiden nei de nullewâldsône dêrûnder, om op in oar plak wer omheech te klimmen. Troch minsklike boskboupraktiken ûntstiene der yn 'e tweintichste iuw lykwols iepen plakken yn 'e nullewâldsône dy't krekt wiene wat jonge marmotten sochten; se seagen dus net mear fierder om, mar setten har dêr nei wenjen. Lykwols groeit it nullewâld sa fluch werom dat sokke habitats nei in pear marmottegeneraasjes ûngaadlik foar har fuortbestean wurde. De marmotten dy't dêr libje, komme dan om, mei't har fretten net mear foarhâns is. Sadwaande hat de boskbou soarge dat der "sinkgatten" ûntstiene dêr't in oansjenlik part fan 'e marmottepopulaasje yn ferdwûn is. Ut in ûndersyk út 2005 hat bliken dien dat ek de ynfloed fan 'e minsklike boskbou op it foarkommen en de predaasjepraktiken fan rôfdieren lykas de keningsearn, de poema en de wolf hjirby foar 't neist in rol spile hat.
De Vancouvereilânmarmot is noch altyd ien fan 'e seldsumste sûchdieren fan 'e wrâld. Yn 1997 wiene der noch mar sa'n bytsje fan oer, dat steatsboskbehear op Vancouvereilân besleat om party te fangen en sa in "genetyske rêdingsboat" te kreëarjen, wêrmei't yn gefal fan útstjerren yn it wyld wer in libbensfetbere populaasje fokt wurde koe. Sadwaande besteane der no groepen Vancouvereilânmarmotten yn finzenskip yn 'e dieretunen fan Toronto en Calgary en yn it Mountainview Conservation and Breeding Centre yn Langley. Teffens is op Vancouvereilân sels in foksintrum boud op 'e Mount Washington. Nei't men by in telling yn 2003 noch mar 21 wylde marmotten op it hiele eilân gewaarwurde koe, waard begûn mei it útsetten yn it wyld fan eksimplaren dy't ûnderwilens yn finzenskip fokt wiene. Tusken 2000 en 2010 waarden der 442 jongen yn finzenskip berne dy't oerlibbe hiene oant se ôfwûn wurde koene. De populaasje yn it wyld waard yn 2013 rûst op 350-400 eksimplaren.
De Vancouvereilânmarmot (Latynske namme: Marmota vancouverensis) is in sûchdier út it skift fan 'e kjifdieren (Rodentia), de famylje fan 'e iikhoarntsjes (Sciuridae) en it skaai fan 'e marmotten (Marmota), dat fan natuere inkeld foarkomt op Vancouvereilân, foar de súdwestkust fan Kanada. Dizze soarte is oan 'e grutte kant foar in marmot, en is nau besibbe oan 'e Olympyske marmot en de grize marmot, dy't deunby op dielen fan it fêstelân fan Noard-Amearika foarkomme. De Vancouvereilânmarmot is slim yn syn fuortbestean bedrige, dat der is no in fokprogramma foar eksimplaren yn finzenskip opset om him fan it útstjerren te rêden.
The Vancouver Island marmot (Marmota vancouverensis) naturally occurs only in the high mountains of Vancouver Island, in British Columbia.[3] This particular marmot species is large compared to some other marmots, and most other rodents. Marmots as a group are the largest members of the squirrel family, with weights of adults varying from 3 to 7 kg depending on age and time of year.[4]
Although endemic to Vancouver Island, Marmota vancouverensis now also resides successfully at several captive breeding centres across Canada as well as several sites on Vancouver Island at which local extinction was observed during the 1990s.[5][6][7] This is the result of an ongoing recovery program designed to prevent extinction and restore self-sustaining wild populations of this unique Canadian species.[8][9] Due to the efforts of the recovery program, the marmot count in the wild increased from fewer than 30 wild marmots in 2003, to an estimated 250–300 in 2015.[10]
The Vancouver Island marmot is typical of alpine-dwelling marmots in general form and physiology. However this species can be easily distinguished from other marmots by its rich, chocolate brown fur and contrasting white patches. No other marmot species naturally occurs on Vancouver Island.[11] The Vancouver Island marmot, as its name suggests, is geographically restricted to Vancouver Island, and apparently evolved rapidly since retreat of the Cordilleran glaciation some 10,000 years before present.[12] Marmota vancouverensis is distinct from other marmot species in terms of morphology,[13] genetics,[14] behaviour,[15] and ecology.[16]
An adult Vancouver Island marmot typically measures 65 to 70 centimetres from the tip of its nose to the tip of its tail. However, weights show tremendous seasonal variation. An adult female that weighs 3 kilograms when she emerges from hibernation in late April can weigh 4.5 to 5.5 kg by the onset of hibernation in late September or October. Adult males can be even larger, reaching weights of over 7.5 kg. In general, marmots lose about one-third of their body mass during the six-and-a-half months in which they hibernate during winter.[17]
The marmots on Vancouver Island are exclusively herbivores and burrow dwellers like all marmots. Over 30 varieties of food plants have been observed being consumed by marmots on Vancouver Island, who typically switch from grasses in the early spring to plants like lupines in the late summer.[18] Marmots hibernate for various amounts of time depending upon site characteristics and annual weather conditions. Wild Vancouver Island marmots hibernate, on average, for about 210 days of the year, generally from late September or early October until late April or early May. They generally hibernate for shorter periods in captivity.[19]
Vancouver Island marmots typically first breed at three or four years of age, although some have been observed to breed as two-year-olds.[20] Marmots breed soon after emergence from hibernation. Gestation is thought to be approximately 30–35 days. Litter sizes average 3-4 pups, and weaned pups generally emerge above ground for the first time in early July.
Systematic marmot surveys have been conducted since 1979, with variable count effort and coverage of the Island.[21] Suitable meadows are rare[22] compared to nearby regions of the British Columbian mainland or the Olympic peninsula of Washington State; habitat scarceness is believed to be the primary reason for the rarity of this marmot species. Most marmots live above 1000 metres elevation in meadows that face south to west. It is believed that populations expanded during the 1980s. Some natural meadows may be kept clear of invading trees by snow-creep and periodic avalanches or fire.
Causes of marmot population declines are numerous. Over the long term (i.e., periods involving thousands of years), climate changes have caused both increases and declines of open alpine habitat that constitute suitable marmot habitat.[23] Over more recent time scales, population dynamics may have been influenced by short-term weather patterns and systematic changes in the landscape. In particular, forest clearcutting at low elevations[24] likely altered dispersal patterns. Sub-adult marmots typically disperse from the subalpine meadows in which they were born. Dispersal involves traversing lowland conifer forests and valleys to other subalpine meadows. However, clearcutting has provided marmots with new open areas which constitute habitat. Unfortunately, rapid forest regeneration makes such man-made habitats unsuitable over a few years. One study concluded that clearcuts therefore act as a kind of population "sink" in which long-term reproduction and survival rates are reduced to the point of unsustainability[20] One 2005 study concluded the main cause of recent decline to be predation "associated with forestry and altered predator abundance and hunting patterns".[25] This study also revealed seasonal variations in mortality rates, where the probability of death was low during hibernation, and high in August.[25] Major predators upon Vancouver Island marmots include golden eagles (Aquila chrysaetos), cougars (Puma concolor) and wolves (Canis lupus).[26]
The population crash may also be due to the Allee effect, named after zoologist Warder Clyde Allee. Allee proposed that social animals require a critical mass in order to survive, because survival requires group activities such as warning of predators and migration. A decline below that threshold precipates rapid decline. Ecologist Justin Brashares suggests that at least some of the marmot's group behavior is learned, so that the loss of marmot "culture" has caused them to become more solitary, and interact aggressively rather than cooperatively when they do encounter each other.[27]
The endangered Vancouver Island marmot remains one of the world's rarest mammals. In 1997 there were so few numbers of marmots on Vancouver Island that managers took the bold step of capturing some to create a "genetic lifeboat" and therefore create the possibility of restoring wild populations. The first marmots went to Toronto Zoo in 1997, but this initial effort was quickly followed by efforts made by the Calgary Zoo and Mountainview Conservation and Breeding Centre in Langley, BC.[6]
In 1998 a new model for species recovery was born involving the government, private industry and public donors. A census in late 2003 resulted in a count of only 21 wild marmots known to be present on Vancouver Island. After these findings, marmots were released from captivity in different places to try to get the population back up to a reasonable number.
These marmots are still classified as endangered.[28] The cumulative captive breeding program has steadily grown, with 130 individuals in captivity (2010) and 442 weaned pups born in captivity since 2000. A number of individuals have been released to Strathcona Provincial Park, Mount Cain, Mount Washington and more southern mountains.
The Marmot Recovery Foundation built a dedicated marmot facility on Mt. Washington, Vancouver Island to further facilitate captive breeding and pre release conditioning. The fundamental idea was to produce marmots in a fashion that would facilitate their eventual return to the wild. From 2003–2010 the Marmot Recovery Foundation and the British Columbia Ministry of Environment have released 308 marmots back into the wild.[29] More releases are expected in the upcoming years to increase the wild population, estimated at 250–300 individuals in 2010, and 350–400 individuals in 2013. The wild population was counted at 250 in 2021.[30] Due to conservation and recovery efforts, the population of Vancouver Island Marmots has increased drastically since 2003 to present day. Nevertheless, Vancouver Island Marmot populations continue to fluctuate due to natural events or increased predation, leading to an inconsistent annual mortality rate.[31]
Based on genetic analyses, the closest relatives of the Vancouver Island marmot are the hoary marmot (Marmota caligata) and the Olympic marmot (Marmota olympus).[32] There is some debate, on genetic grounds, about which of the two nearby mainland species is most closely related to the Vancouver Island marmot or when marmots first arrived on the island.[33] The differences in DNA observed between species is small. In 2009, Nagorsen and Cardini identified, from museum specimens, substantial physical differences between species that can only be explained by rapid evolution in a relatively isolated island context.[34]
Because of their endangered status, Vancouver Island marmots have become a conservation symbol in British Columbia.
In 2023, the Vancouver Island marmot will be featured on a United States Postal Service Forever stamp as part of the Endangered Species set, based on a photograph from Joel Sartore's Photo Ark. The stamp will be dedicated at a ceremony at the National Grasslands Visitor Center in Wall, South Dakota.[39]
The Vancouver Island marmot (Marmota vancouverensis) 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 as a group are the largest members of the squirrel family, with weights of adults varying from 3 to 7 kg depending on age and time of year.
Although endemic to Vancouver Island, Marmota vancouverensis now also resides successfully at several captive breeding centres across Canada as well as several sites on Vancouver Island at which local extinction was observed during the 1990s. This is the result of an ongoing recovery program designed to prevent extinction and restore self-sustaining wild populations of this unique Canadian species. Due to the efforts of the recovery program, the marmot count in the wild increased from fewer than 30 wild marmots in 2003, to an estimated 250–300 in 2015.
La marmota de Vancouver (Marmota vancouverensis) es una especie de roedor esciuromorfo de la familia Sciuridae endémica de las tierras más altas de la isla de Vancouver en el Noroeste del Pacífico, fácilmente diferenciable de otras marmotas por su largo y espeso pelaje de color marrón oscuro, salpicado de manchas blancas. En la actualidad sólo existen alrededor de un centenar de individuos, lo que convierte a esta marmota en uno de los mamíferos más raros. La población actual[¿cuándo?] es el resultado de una política de cría en cautividad que ha conseguido triplicar los treinta ejemplares salvajes que sobrevivían en 2003. Su pariente más cercano es la marmota silbadora del noroeste de Norteamérica.
Vive en pequeñas colonias en las laderas de las montañas de la isla, por encima del límite de la vegetación arbórea, teniendo sus madrigueras casi siempre orientadas hacia el sur. Pasa cerca de ocho meses al año hibernando en su interior. Al acabar la hibernación, a comienzos de la primavera, tiene lugar la época de celo; treinta días después, las hembras fecundadas, dan a luz a de tres a cinco crías. Hacia los dos años alcanzan la madurez sexual y abandonan al grupo familiar, con el fin de encontrar pareja y un nuevo territorio donde instalar su propia madriguera.
La alimentación es puramente herbívora, basada en la ingesta de bayas, flores, hojas, raíces y tallos. Entre sus depredadores se incluyen el águila real, el halcón de cola roja, el puma y el oso negro americano. Los humanos no las cazan, pero el impacto de su actividad en la isla y la consiguiente pérdida del hábitat de las marmotas representa una considerable amenaza para estas.
La marmota de Vancouver (Marmota vancouverensis) es una especie de roedor esciuromorfo de la familia Sciuridae endémica de las tierras más altas de la isla de Vancouver en el Noroeste del Pacífico, fácilmente diferenciable de otras marmotas por su largo y espeso pelaje de color marrón oscuro, salpicado de manchas blancas. En la actualidad sólo existen alrededor de un centenar de individuos, lo que convierte a esta marmota en uno de los mamíferos más raros. La población actual[¿cuándo?] es el resultado de una política de cría en cautividad que ha conseguido triplicar los treinta ejemplares salvajes que sobrevivían en 2003. Su pariente más cercano es la marmota silbadora del noroeste de Norteamérica.
Marmota vancouverensis Marmota generoko animalia da. Karraskarien barruko Xerinae azpifamilia eta Sciuridae familian sailkatuta dago.
Marmota vancouverensis Marmota generoko animalia da. Karraskarien barruko Xerinae azpifamilia eta Sciuridae familian sailkatuta dago.
La marmotte de l’île de Vancouver (Marmota vancouverensis) est une espèce de petit mammifère appartenant à la famille des sciuridés, qui n'est présente que sur quelques flancs abrupts des collines de l'Île de Vancouver au Nord-Ouest Pacifique.
Elle est considérée comme en voie de disparition (classement Espèce en danger critique d'extinction, avec 36 individus en liberté répertoriés en 2000, et environ 300 individus en 2017), et fait l'objet de tentatives de préservation de la part du Gouvernement du Canada.
Les marmottes de l'île de Vancouver ont à l'âge adulte une taille comparable à celle d'un grand chat. Les individus adultes ont une longueur d'environ 60 à 70 cm.
Le dimorphisme sexuel de l'espèce se manifeste essentiellement via la masse des individus. Les mâles adultes atteignent un poids de 6 à 7 kg, tandis que les femelles atteignent généralement 5 kg. La fourrure des Marmottes de l'île de Vancouver est de couleur brunne, avec des taches blanches au niveau des joues.
Les Marmottes de l'île de Vancouver ont de longues griffes, caractéristiques des mammifères fouisseurs, qui leur permettent de creuser galeries et terriers. Leurs incisives sont allongées, comme celles des castors.
Les femelles de l'espèce sont fertiles entre trois et quatre ans. Les portées sont composées d'environ trois petits.
La Marmotte de l'île de Vancouver vit dans des prairies alpines, naturellement élevées. Les prairies fournissent les végétaux et l'eau. Le type de sol doit permettre de creuser des terriers où elles hibernent et élèvent leurs petits.
La perte d'habitat est considérée comme la raison principale de la rareté des espèces de marmottes, dont celle de l'île de Vancouver. Les coupes d'arbres par l'homme dans les forêts créent des prairies où elles peuvent vivre, mais la repousse rapide des arbres détruit cet habitat en quelques années.
Malgré le peu d'interactions entre la marmotte de l'île de Vancouver et l'espèce humaine, l'activité de cette dernière a abouti à la quasi-extinction de cette espèce, en raison des coupes à blanc des forêts qui ont ainsi détruit l'habitat normal des marmottes.
L'animal est depuis en voie de disparition[1], et classé en danger critique d'extinction.
Cette espèce n'a alors survécu que grâce aux entreprises d'élevage en captivité, s'inscrivant dans les efforts de préservation de l'espèce de la part du Gouvernement du Canada[2]. Il n'existe que 250-300 individus à l'état sauvage (2017).
La marmotte de l’île de Vancouver (Marmota vancouverensis) est une espèce de petit mammifère appartenant à la famille des sciuridés, qui n'est présente que sur quelques flancs abrupts des collines de l'Île de Vancouver au Nord-Ouest Pacifique.
Elle est considérée comme en voie de disparition (classement Espèce en danger critique d'extinction, avec 36 individus en liberté répertoriés en 2000, et environ 300 individus en 2017), et fait l'objet de tentatives de préservation de la part du Gouvernement du Canada.
La marmotta di Vancouver (Marmota vancouverensis) è riscontrabile solo nelle regioni montuose dell'Isola di Vancouver e della Nord-ovest Pacifico.[2]
La marmotta di Vancouver può essere facilmente distinguibile da altre specie di marmotta principalmente dalla colorazione marrone-rossiccia con piccole macchie bianche. Nessun'altra specie di marmotta abita l'isola di Vancouver.[3] Pare che questa specie di marmotta si sia evoluta rapidamente dal retrocedere del ghiacciaio circa 10.000 anni fa, raggiungendo una lunghezza di 56-70 cm e un peso che varia dai 3 kg degli esemplari femmine quando emergono dal letargo ai 7 kg dei maschi prima dell'ibernazione, le femmine prima del letargo pesano circa 4,5-5,5 kg.[4]
Come tutte le marmotte, le marmotte di Vancouver vivono in gruppi e sono rigorosamente vegetariane cibandosi di più di 30 specie di piante.[5] La durata del letargo in queste marmotte dipende dalle caratteristiche dell'habitat e dalle condizioni climatiche, nelle popolazioni selvatiche il letargo dura circa 210 giorni, generalmente da fine settembre o inizio ottobre fino a fine aprile o inizio maggio. Gli esemplari in cattività ibernano generalmente per periodi più brevi.[6]
Queste marmotte iniziano a riprodursi generalmente verso i tre e i quattro anni, anche se sono stati osservati esemplari di due anni in grado di riprodursi.[7] La marmotta di Vancouver si riproduce appena dopo il risveglio dall'ibernazione, la gestazione dura da 30 a 35 giorni. Le femmine hanno normalmente da tre a quattro cuccioli alla volta, le femmine con i cuccioli riemergono dal letargo normalmente verso l'inizio di luglio.
Queste marmotte sono classificate come in pericolo critico. Il progetto di allevamento in cattività è in continua crescita, con 130 individui in cattività nel 2010 e 442 cuccioli nati sempre in cattività dal 2000. Alcuni individui sono stati rilasciati in natura col fine di aumentare la popolazione naturale.
Alla luce di studi genetici si crede che le marmotte più strettamente imparentate con la marmotta di Vancouver siano la marmotta hoary (Marmota caligata) e la marmotta olimpica (Marmota olympus).[8]
La marmotta di Vancouver (Marmota vancouverensis) è riscontrabile solo nelle regioni montuose dell'Isola di Vancouver e della Nord-ovest Pacifico.
De vancouvermarmot (Marmota vancouverensis) is een zoogdier uit de familie van de eekhoorns (Sciuridae). De wetenschappelijke naam van de soort werd voor het eerst geldig gepubliceerd door Swarth in 1911.
De soort komt voor in Canada.
Bronnen, noten en/of referentiesDe vancouvermarmot (Marmota vancouverensis) is een zoogdier uit de familie van de eekhoorns (Sciuridae). De wetenschappelijke naam van de soort werd voor het eerst geldig gepubliceerd door Swarth in 1911.
Multimedia w Wikimedia Commons Świstak wyspowy[2], świstak z Vancouver (Marmota vancouverensis) - gatunek gryzonia z rodziny wiewiórkowatych, jeden z przedstawicieli rodzaju Marmota.
Występowanie: Kanadyjska wyspa Vancouver.
Opis: Umaszczenie czarne na wiosnę i jedwabiście brązowe w lecie; koniec pyska żółty.
Liczebność: Poniżej 1000 osobników (być może zaledwie 200) rozrzuconych w kilku koloniach.
Świstak wyspowy, świstak z Vancouver (Marmota vancouverensis) - gatunek gryzonia z rodziny wiewiórkowatych, jeden z przedstawicieli rodzaju Marmota.
Występowanie: Kanadyjska wyspa Vancouver.
Opis: Umaszczenie czarne na wiosnę i jedwabiście brązowe w lecie; koniec pyska żółty.
Liczebność: Poniżej 1000 osobników (być może zaledwie 200) rozrzuconych w kilku koloniach.
A marmota da Ilha de Vancouver (Marmota vancouverensis) ocorre naturalmente apenas nas altas montanhas da Ilha de Vancouver, na Colúmbia Britânica.[1] Esta espécie de marmota em particular é grande se comparada a algumas outras marmotas e à maioria dos outros roedores. As marmotas como grupo são os maiores membros da família dos esquilos, com peso dos adultos variando de 3 a 7 kg dependendo da idade e época do ano.
Embora endêmico na Ilha de Vancouver, Marmota vancouverensis agora também reside com sucesso em vários centros de reprodução em cativeiro em todo o Canadá, bem como em vários locais na Ilha de Vancouver onde a extinção local foi observada durante a década de 1990. Este é o resultado de um programa de recuperação em andamento projetado para prevenir a extinção e restaurar as populações selvagens autossustentáveis desta espécie canadense única. Devido aos esforços do programa de recuperação, a contagem de marmotas na natureza aumentou de menos de 30 marmotas selvagens em 2003, para cerca de 250–300 em 2015.
A marmota da Ilha de Vancouver é típica das marmotas alpinas em sua forma e fisiologia geral. No entanto, esta espécie pode ser facilmente distinguida de outras marmotas por sua rica pele marrom chocolate e manchas brancas contrastantes. Nenhuma outra espécie de marmota ocorre naturalmente na Ilha de Vancouver. A marmota da Ilha de Vancouver, como seu nome sugere, é geograficamente restrita à Ilha de Vancouver e, aparentemente, evoluiu rapidamente desde o recuo da glaciação da Cordilheira cerca de 10.000 anos antes do presente. Marmota vancouverensis é diferente de outras espécies de marmota em termos de morfologia, genética, comportamento, e ecologia.
Uma marmota adulta da Ilha de Vancouver mede normalmente de 56 a 70 centímetros da ponta do nariz à ponta da cauda. No entanto, os pesos mostram uma grande variação sazonal. Uma fêmea adulta que pesa 3 kg quando sai da hibernação no final de abril pode pesar 4,5 a 5,5 kg no início da hibernação no final de setembro ou outubro. Os machos adultos podem ser ainda maiores, chegando a pesar mais de 7 kg. Em geral, as marmotas perdem cerca de um terço de sua massa corporal durante os seis meses e meio em que hibernam durante o inverno.
Como todas as marmotas, as marmotas da Ilha de Vancouver vivem em tocas e são herbívoros obrigatórios. Foi documentado que as marmotas da Ilha de Vancouver comem mais de 30 espécies de plantas alimentícias, geralmente mudando de gramíneas no início da primavera para plantas como tremoços no final do verão. marmotas hibernam por vários períodos, dependendo das características do local e das condições climáticas anuais. As marmotas selvagens da Ilha de Vancouver hibernam, em média, cerca de 210 dias por ano, geralmente do final de setembro ou início de outubro até o final de abril ou início de maio. Eles geralmente hibernam por períodos mais curtos em cativeiro.
Normalmente, as marmotas da Ilha de Vancouver se reproduzem pela primeira vez aos três ou quatro anos de idade, embora algumas tenham se reproduzido aos dois anos. marmotas se reproduzem logo após emergirem da hibernação. A gestação é estimada em aproximadamente 30-35 dias. O tamanho da ninhada é em média de 3-4 filhotes, e os filhotes desmamados geralmente surgem acima do solo pela primeira vez no início de julho.
Levantamentos sistemáticos de marmotas têm sido realizados desde 1979, com esforço de contagem variável e cobertura da Ilha. Prados adequados são raros comparação com as regiões próximas do continente colombiano britânico ou da península olímpica do estado de Washington; a escassez de habitat é considerada a principal razão para a raridade desta espécie de marmota. A maioria das marmotas vive acima de 1000 metros de altitude em prados voltados para o sul a oeste. Acredita-se que as populações se expandiram durante a década de 1980. Alguns prados naturais podem ser mantidos longe de árvores invasoras por neve e avalanches periódicas ou incêndios.
As causas do declínio da população de marmotas são numerosas. No longo prazo (ou seja, períodos envolvendo milhares de anos), as mudanças climáticas causaram aumentos e declínios do habitat alpino aberto que constitui o habitat adequado para marmotas. Em escalas de tempo mais recentes, a dinâmica da população pode ter sido influenciada por padrões climáticos de curto prazo e mudanças sistemáticas na paisagem. Em particular, corte raso de floresta em baixas elevações prováveis padrões de dispersão alterados. As marmotas subadultas geralmente se dispersam nos prados subalpinos em que nasceram. A dispersão envolve a travessia de florestas de coníferas de planície e vales para outros prados subalpinos. No entanto, o corte raso proporcionou às marmotas novas áreas abertas que constituem o habitat. Infelizmente, a rápida regeneração da floresta torna esses habitats feitos pelo homem inadequados ao longo de alguns anos. Um estudo concluiu que os cortes desmatados, portanto, agem como uma espécie de "sumidouro" da população em que as taxas de reprodução e sobrevivência a longo prazo são reduzidas ao ponto da insustentabilidade Um estudo de 2005 concluiu que a principal causa do declínio recente é a predação "associada com silvicultura e abundância alterada de predadores e padrões de caça ". Os principais predadores das marmotas da Ilha de Vancouver incluem águias-reais (Aquila chrysaetos), pumas (Puma concolor) e lobos (Canis lupus).
A queda populacional também pode ser devido ao efeito Allee, em homenagem ao zoólogo Warder Clyde Allee. Allee propôs que os animais sociais requerem uma massa crítica para sobreviver, porque a sobrevivência requer atividades em grupo, como alerta de predadores e migração. Um declínio abaixo desse limite precipita um declínio rápido. O ecologista Justin Brashares sugere que pelo menos parte do comportamento grupal da marmota seja aprendido, de modo que a perda da "cultura" da marmota fez com que se tornassem mais solitárias e interajam mais agressivamente do que cooperativamente quando se encontram.
A ameaçada marmota da Ilha de Vancouver continua sendo um dos mamíferos mais raros do mundo. Em 1997, havia tão poucos números de marmotas na Ilha de Vancouver que os administradores deram o passo ousado de capturar algumas para criar um "barco salva-vidas genético" e, portanto, criar a possibilidade de restaurar as populações selvagens. As primeiras marmotas foram para o Zoológico de Toronto em 1997, mas esse esforço inicial foi rapidamente seguido por esforços feitos pelo Zoológico de Calgary e pelo Centro de Conservação e Reprodução de Mountainview em Langley, BC. A Marmot Recovery Foundation também construiu uma instalação dedicada a marmotas em Mt. Washington, Ilha de Vancouver, para facilitar ainda mais a reprodução em cativeiro e o condicionamento pré-soltura. A ideia fundamental era produzir marmotas de uma maneira que facilitasse seu eventual retorno à natureza.
Em 1998 nasceu um novo modelo de recuperação de espécies envolvendo governo, indústria privada e doadores públicos. Um censo no final de 2003 resultou na contagem de apenas 21 marmotas selvagens conhecidas por estarem presentes na Ilha de Vancouver. Após essas descobertas, as marmotas foram libertadas do cativeiro em diferentes lugares para tentar fazer com que a população voltasse a um número razoável.
Essas marmotas ainda são classificadas como ameaçadas de extinção. O programa cumulativo de reprodução em cativeiro tem crescido constantemente, com 130 indivíduos em cativeiro (2010) e 442 filhotes desmamados nascidos em cativeiro desde 2000. Vários indivíduos foram liberados para Strathcona Provincial Park, Mount Cain, Mount Washington e mais ao sul montanhas. De 2003 a 2010, a Marmot Recovery Foundation e o Ministério do Meio Ambiente da Colúmbia Britânica libertaram 308 marmotas de volta à natureza. Mais lançamentos são esperados nos próximos anos para aumentar a população selvagem, estimada em 250-300 indivíduos em 2010, e 350-400 indivíduos em 2013.
Com base em análises genéticas, os parentes mais próximos da marmota da Ilha de Vancouver são a marmota caligata (Marmota caligata) e a marmota olímpica (Marmota olympus). Há algum debate, por motivos genéticos, sobre qual das duas espécies continentais próximas está mais intimamente relacionada à marmota da Ilha de Vancouver ou quando as marmotas chegaram pela primeira vez à ilha. As diferenças no DNA observadas entre as espécies são pequenas. Em 2009, Nagorsen e Cardini identificaram, a partir de espécimes de museu, diferenças físicas substanciais entre as espécies que só podem ser explicadas pela rápida evolução em um contexto de ilha relativamente isolado.
https://andrewabryantservices.files.wordpress.com/2018/08/bryant_2007_reintroduction_news.pdf
https://andrewabryantservices.files.wordpress.com/2014/05/bryant-and-page-2005.pdf
https://doi.org/10.1080%2F106351599259988
https://en.wikipedia.org/wiki/Vancouver_Island_marmot
A marmota da Ilha de Vancouver (Marmota vancouverensis) ocorre naturalmente apenas nas altas montanhas da Ilha de Vancouver, na Colúmbia Britânica. Esta espécie de marmota em particular é grande se comparada a algumas outras marmotas e à maioria dos outros roedores. As marmotas como grupo são os maiores membros da família dos esquilos, com peso dos adultos variando de 3 a 7 kg dependendo da idade e época do ano.
Embora endêmico na Ilha de Vancouver, Marmota vancouverensis agora também reside com sucesso em vários centros de reprodução em cativeiro em todo o Canadá, bem como em vários locais na Ilha de Vancouver onde a extinção local foi observada durante a década de 1990. Este é o resultado de um programa de recuperação em andamento projetado para prevenir a extinção e restaurar as populações selvagens autossustentáveis desta espécie canadense única. Devido aos esforços do programa de recuperação, a contagem de marmotas na natureza aumentou de menos de 30 marmotas selvagens em 2003, para cerca de 250–300 em 2015.
Vancouvermurmeldjur (Marmota vancouverensis[2][3][4][5][6][7][8][9]) är en däggdjursart som beskrevs av Harry Schelwald Swarth 1911. Den ingår i släktet murmeldjur och familjen ekorrar.[10][11] Inga underarter finns listade.[10]
Vancouvermurmeldjuret skiljer sig från andra murmeldjur genom sin mycket mörka, chokladbruna päls med oregelbundna, vita fläckar vid nos, panna, haka och bröst. Årsungarna har enfärgat mörka, nästan svarta pälsar som under sommaren bleknar till en rödbrun färg. Kroppen är robust med korta, kraftiga ben och fötter med kraftiga grävklor. Kroppslängden är mellan 56 och 70 cm inklusive den buskiga svansen.[12] Vikten varierar mycket med kön och tiden på året: Honan kan väga mellan 4,5 och 5,5 kg just före vintersömnen, men bara 3 kg efter. Hanen kan väga upp till 7 kg före vintersömnen.[13]
Murmeldjuret lever endemiskt på sydöstra Vancouver Island vid Kanadas västra kustlinje. Regionen ligger 900 till 1 500 meter över havet.[1]
Habitatet utgörs av kraftigt sluttande bergsängar utan eller med glest fördelade träd, påverkade av laviner och gärna med rik ört- och buskvegetation. Arten bygger även bon i barrskog och biotoper som skapats av människan, till exempel vägbankar, kalhyggen eller skidpister.[1] Arten konstruerar underjordiska bon som kan vara mycket omfattande. Ett sådant bo var över 4 meter långt och hade en bokammare på mer än en meters djup. Bona har ofta flera ingångar, vanligen med en diameter på 30 till 45 cm och belägna under en stubbe eller på nedåtsidan av stenbumlingar i sluttningar. Ett bo kan användas flera år i följd. Dessutom gräver arten ut enkla skydd under klippor eller trädrötter, där den kan gömma sig för fiender.[13]
Arten är dagaktiv och äter främst på morgnar och kvällar. Födan består framför allt av gräs, blommor, frukter och knoppar. Den kan även ta de späda spetsarna på örnbräken. På våren förtär arten främst gräs som knägräs (Danthonia intermedia), frylen och starr. Till sommaren övergår den till att äta blommor som rutor, skärmliljor, lokor och ullbladsarter, för att på sensommaren övergå till bredbladiga växter som lupiner och vialer.[12]
Själv utgör arten föda för vargar, pumor, kungsörn och vithövdad havsörn.[12]
Vancouvermurmeldjuret lever i små kolonier som destår av en vuxen hane, en till två vuxna honor, ungdjur och årsungar. Arten är ofta monogam, även om polygama förhållanden också förekommer. Parningen sker högst en gång om året (det är inte ovanligt med ett intervall på ett till två år mellan parningstillfällena) i de underjordiska bona strax efter vintersömnen avslutats under tidig vår. Efter en dräktighet på omkring 32 dygn föder honan mellan 1 och 7 ungar (vanligen 3 till 4) som dias i omkring en månad. Arten blir könsmogen mellan 2 och 4 års ålder, och lever till omkring 10 års ålder (maximum uppskattas till mellan 12 och 15 år).[12]
Arten sover vintersömn i en djupt belägen bohåla fylld med växtdelar som isolering och med ingången igentäppt med jord och stenar. Hela kolonier övervintrar tillsammans. Vintersömnen varar vanligen mellan sent i september till sent i april.[12] Den är en äkta vinterdvala, med kroppstemperaturen sänkt till mellan 6 och 9º C.[14]
IUCN kategoriserar arten globalt som akut hotad, och populationen har minskat kraftigt. 2004 var antalet vildlevande medlemmar av arten nere i 35, plus 93 som uppfötts i fångenskap.[1] Uppfödningscenta har upprättats både på Vancouver Island och andra platser i Kanada[15] och 2010 uppskattas den vilda populationen ha ökat till omkring 300 individer.[12] En möjlig orsak till minskningen kan vara att svartsvanshjorten har minskat på Vancouver Island; då denna var huvudfödan för områdets pumor och vargar, antas det att dessa rovdjur i stället i ökad grad börjat äta vancouvermurmeldjur.[12] Även om det moderna skogsbrukets kalhyggen verkar ha gynnat murmeldjuret genom att förse detta med lämpliga, trädfattiga habitat, menar många forskare att de i det långa loppet haft en negativ inverkan, eftersom de har gjort det svårare för djuren att hitta lämpliga ställen för sin övervintring.[1]
Wikimedia Commons har media som rör Vancouvermurmeldjur.
Wikispecies har information om Marmota vancouverensis.
Vancouvermurmeldjur (Marmota vancouverensis) är en däggdjursart som beskrevs av Harry Schelwald Swarth 1911. Den ingår i släktet murmeldjur och familjen ekorrar. Inga underarter finns listade.
Хутро чорного кольору навесні й шовковисте коричневе влітку, кінець морди жовтий. Дорослий бабак зазвичай має довжину від 65 до 70 см від кінчика носа до кінчика хвоста. Самці можуть досягати ваги понад 7 кг.
Наприкінці зимової сплячки на початку весни відбувається шлюбний сезон, 30 днів по тому, запліднені самиці народжують 3-5 дитинчат. До двох років вони досягають статевої зрілості і залишають сімейну групу, для того, щоб знайти собі пару і нову територію.
Трави і осоки є найбільш важливою їжею на початку весни; різнотрав'я складають основну частину річного раціону. Невеликі плоди також споживаються. Зимує з початку жовтня до початку травня. Хижацтво на М. vancouverensis не вивчене, але потенційними хижаками є Canis lupus, Martes americana, Gulo gulo, Felis concolor, Ursus americanus, Buteo jamaicensis, Aquila chrysaetos, Accipiter gentilis, and Bubo virginianus. Люди не полюють, але вплив людської діяльності на острові і, як наслідок втрата середовища існування бабаків являє собою значну загрозу для них. Живе в невеликих колоніях на схилах гір острова, вище межі деревної рослинності, його нори майже завжди орієнтовані на південь.
Marmota vancouverensis là một loài động vật có vú trong họ Sóc, bộ Gặm nhấm. Loài này được Swarth mô tả năm 1911.[2]
Marmota vancouverensis là một loài động vật có vú trong họ Sóc, bộ Gặm nhấm. Loài này được Swarth mô tả năm 1911.
Ванкуверский сурок[1] (лат. Marmota vancouverensis) — североамериканский грызун рода сурков, семейства беличьих. Эндемичен для острова Ванкувер в Канаде, обитает в основном на юге острова. Обитает в горах высотой около полутора километров. Этот сурок представляет собой отдельный вид, отнесённый к числу исчезающих (в природе осталось менее 35 особей).
Мех ванкуверских сурков в зависимости от сезона имеет разный цвет. В начале лета — коричневый, в июле мех линяет и становится чёрным с белыми полосками на верхней части головы и на теле. Вес сурков также зависит от сезона. В течение года вес может варьироваться от 3—3,5 кг до 5—6 кг. Длина тела — 68—70 см.
Полового развития сурки достигают в возрасте трёх лет. Большинство самок размножаются лишь в 4 года, с нерепродуктивным периодом между появлением потомства в 1 год. Продолжительность жизни выше у самок, чем у самцов. Наиболее вероятная смерть сурков — нападение хищников, а также смерть во время зимней спячки[2][3].
Ванкуверский сурок (лат. Marmota vancouverensis) — североамериканский грызун рода сурков, семейства беличьих. Эндемичен для острова Ванкувер в Канаде, обитает в основном на юге острова. Обитает в горах высотой около полутора километров. Этот сурок представляет собой отдельный вид, отнесённый к числу исчезающих (в природе осталось менее 35 особей).
Мех ванкуверских сурков в зависимости от сезона имеет разный цвет. В начале лета — коричневый, в июле мех линяет и становится чёрным с белыми полосками на верхней части головы и на теле. Вес сурков также зависит от сезона. В течение года вес может варьироваться от 3—3,5 кг до 5—6 кг. Длина тела — 68—70 см.
Полового развития сурки достигают в возрасте трёх лет. Большинство самок размножаются лишь в 4 года, с нерепродуктивным периодом между появлением потомства в 1 год. Продолжительность жизни выше у самок, чем у самцов. Наиболее вероятная смерть сурков — нападение хищников, а также смерть во время зимней спячки.
밴쿠버섬마멋(Marmota vancouverensis)은 다람쥐과에 속하는 설치류의 일종이다. 태평양 북서부 밴쿠버섬 고지대 산악 지역에서만 발견된다. 특히 밴쿠버섬마멋은 일부 다른 마멋류와 대부분의 다른 설치류와 비교하여 상대적으로 크다. 마멋속은 다람쥐과에서 가장 큰 분류군으로 성체의 몸무게가 나이와 시간에 따라서 3~7kg으로 다양하다.[2]
밴쿠버 섬의 고유종이지만, 밴쿠버섬마멋은 현재 캐나다 전역의 여러 사육 번식 센터와 1990년대 동안에 현지에서 멸종된 밴쿠버 섬의 여러 곳에 성공적으로 살고 있다.[3][4] 이는 독특한 캐나다 종의 멸종 방지와 자립적인 야생 개체군 복원을 위해 고안된 지속적인 복원 프로그램의 결과이다.[5][6] 복원 프로그램의 노력 때문에 밴쿠버섬마멋은 야생에서 2003년의 30마리 이하에서 2015년 추산 250~300마리로 증가했다.[7]
다음은 2009년 헬겐(Helgen) 등의 연구에 기초한 계통 분류이다.[8]
마멋족 마멋속
