Back to Science pages 

Published abstracts about Vancouver Island marmots
Compiled by Andrew A. Bryant, Ph.D.
updated: 8 September 2005 		NOTE: Because of copyright restrictions we generally cannot reproduce the complete text of published scientific papers here...
but at least now you'll know where to look!
List of published abstracts (in descending chronological order)
(click on the title to go there, and "back" to return to this list) 		 

2005: Timing and causes of mortality in the endangered Vancouver Island marmot. (available on-line)
2005: Reproductive rates of captive and wild Vancouver Island marmots. (available on-line)
2004: Comparison of discriminant function and classification tree analyses for age classification of marmots.
2004: Endangered Vancouver Island marmots: sentinals of atmospherically delivered contaminants.
2003: Hibernation ecology of wild and captive Vancouver Island marmots. (available on-line)
2002: Disease and unsuccessful reintroduction of Vancouver Island marmots. (available on-line)
2002: Recent population trends in the Vancouver Island marmot. (available on-line)
2001: Treeline dynamics on southern Vancouver Island, British Columbia.
2001: Antipredator behavior of Vancouver Island marmots: using congeners to evaluate abilities...
2000: Relative importance of episodic versus chronic mortality in the decline of V.I. marmots.
2000: National Recovery Plan for the Vancouver Island Marmot. (available on-line)
1998: Metapopulation ecology of Vancouver Island marmots.
1997: Updated status report for the Vancouver Island marmot in Canada.
1996: Demography of Vancouver Island marmots in natural and clearcut environments. (available on-line)
1996. Vancouver Island marmot bones from subalpine caves. (available on-line)
1996: Distribution and abundance of Vancouver Island marmots.
1996: Reproduction and persistence of Vancouver Island marmots in natural and logged habitats.
1994: National recovery plan for the Vancouver Island marmot.
1990: Genetic variability and minimum viable populations in the Vancouver Island marmot.
1986: Seasonal diets of Vancouver Island marmots.
1985: The Vancouver Island marmot: status and management plan. (available on-line)
1984: Vegetation and foraging ecology of the Vancouver Island marmot.
1982: Management of an endangered species: the Vancouver Island marmot.
1981: Helminths of a Vancouver Island marmot.
1977: Behaviour of Vancouver Island marmots.
Other useful references

Bryant, A.A., and R.E. Page. 2005. Timing and causes of mortality in the endangered Vancouver Island marmot (Marmota vancouverensis). Canadian Journal of Zoology. 83: 674-682.

We used radiotelemetry to evaluate seasonal survival rates and mortality factors for a critically endangered island endemic, the Vancouver Island marmot (Marmota vancouverensis Swarth, 1911). Recovery of radio transmitters and marmot remains suggested that predation was the major cause of mortality, accounting for at least 24 of 29 (83%) known-fate deaths recorded since radiotelemetry efforts began in 1992. Wolves (Canis lupus L., 1758) and cougars (Puma concolor (L., 1771)) apparently accounted for 17 deaths (59%). Three marmots (10%) were killed by golden eagles (Aquila chrysaetos (L., 1758)), four (14%) were killed by unknown predators that probably included all of the above species, two (7%) died from unknown causes, and three (10%) died during hibernation in a single burrow. Mortality rates varied seasonally. The daily probability of death during hibernation was very low (Pdeath = 0.016). The probability of death was also low from spring emergence through 31 July (Pdeath = 0.051), but was eight times higher in August (Pdeath = 0.395) and four times higher in September (Pdeath = 0.175). We concluded that predation was the proximate cause of recent declines in wild Vancouver Island marmot populations, that losses were highly concentrated in late summer, and that previous studies exaggerated the importance of winter mortality. We suggest that high predation rates were associated with forestry and altered predator abundance and hunting patterns.

NOTE: The full text of the paper is in *.pdf format here

Bryant, A.A. 2005. Reproductive rates of wild and captiveVancouver Island marmots (Marmota vancouverensis). Canadian Journal of Zoology. 83: 664-673.

I evaluated reproductive rates of the critically endangered Vancouver Island marmot (Marmota vancouverensis Swarth, 1911) using data from captive and wild populations over the 1980–2004 period. Results were similar to those reported for other alpine-dwelling marmots, including the closely related Marmota caligata (Eschscholtz, 1829) and Marmota olympus (Merriam, 1898). Most females in captivity first bred at age 3 or 4 (Tbreed = 4.3 years, SD = 1.15, n = 9), an age not significantly different from that observed in the wild (Tbreed = 3.6 years, SD = 1.2, n = 16). Numbers of pups weaned per litter were similar in captivity (Npups = 3.0, SD = 1.4, n = 25) and in the wild (Npups = 3.4, SD = 1.1, n = 58). Females were capable of weaning pups in consecutive years (46.4%, n = 13) but often skipped 1 year (39.3%, n = 11) or 2 years (14.3%, n = 4) between litters. Two-year-old females weaned pups infrequently (Pbreed = 0.09, n = 43) and older females were far more likely to breed (Pbreed = 0.40, n = 200); in neither case were significant captive–wild differences found. The oldest breeding female was 10 years old, but sample sizes for marmots older than 8 years were small and maximum breeding age may be underestimated. Between-litter intervals in captivity (Tbetween = 1.4 years, SD = 0.7, n = 11) were significantly shorter than in the wild (Tbetween = 1.9 years, SD = 0.7, n = 17). Sex ratios of weaned pups did not differ from 1:1 in the wild (female/male = 1.04) but were significantly skewed towards males in captivity (female/male = 0.56). I conclude that reproductive performance in Vancouver Island marmots is limited both by body condition and social constraints.

NOTE: The full text of the paper is in *.pdf format here

Bryant, A.A., and M. McAdie. 2003. Hibernation ecology of wild and captive Vancouver Island marmots (Marmota vancouverensis). Pages 159 - 166 in R. Ramousse, D. Allaine and M. Le Berre (editors): Adaptive Strategies and Diversity in Marmots. International Marmot Network, Lyon, France.

We evaluated hibernation patterns in wild and captive populations of the critically endangered Vancouver Island marmot (Marmota vancouverensis). Timing and duration of hibernation was significantly altered in captivity. Wild marmots typically began hibernation six weeks earlier and ended hibernation five weeks later than captive marmots. Captive marmots hibernated successfully at a range of temperatures (6-9°) and relative humidities (28-83%). Warmer and dryer conditions generally resulted in shortened hibernation duration. In the wild, solitary marmots hibernated successfully in a variety of habitats and yearlings did not necessarily hibernate with their parents. Daily mass loss rates from torpid marmots suggest that Vancouver Island marmots are efficient hibernators (mean DML = 0.95, 95% CI = 0.89 to 1.01, n = 102). Evidence for social thermoregulation was weak in this species. Hibernation behavior in Vancouver Island marmots may reflect an evolutionary history that encouraged survival in small groups. We caution that interspecific comparisons of hibernation efficiency in free-ranging marmots may be biased by timing of measurements.

NOTE: The complete proceedings of the 4th World Marmot Congress (in English, French and Russian) are available on-line at The International Marmot Network.
I have also provided the full text of the paper in *.pdf format here.

Bryant, A.A., H.M. Schwantje and N.I. de With. 2002. Disease and unsuccessful reintroduction of Vancouver Island marmots (Marmota vancouverensis). Pages 101-107 in K.B. Armitage and V.U. Rumianstev (editors): Holarctic Marmots as a Factor of Biodiversity. ABF Publishing House (Moscow). 411 pp.

In 1996 we conducted an experimental reintroduction of Vancouver Island marmots (Marmota vancouverensis). Six animals were captured from 3 colonies in recently logged habitats and released in a natural sub-alpine meadow. Two males dispersed from the site shortly after release. One male was found dead 5 km from the release site after being killed by a predator; the other was not seen again. The remaining 4 animals bonded to the release site, excavated burrows, foraged, showed typical weight gains and entered hibernation normally. These animals died during the winter of 1996-97. Death may have been caused by a bacterial infection. Our experience underscores the fragility of reintroductions based on small numbers of animals, and illustrates the potential of disease threats to small reintroduced populations.

NOTE: The full text of the paper is in *.pdf format here.

Bryant, A.A., D.W. Janz, M.C. deLaronde and D.D. Doyle. 2002. Recent Vancouver Island marmot (Marmota vancouverensis) population changes. Pages 88-100 in K.B. Armitage and V.U. Rumianstev (editors): Holarctic Marmots as a Factor of Biodiversity. ABF Publishing House (Moscow). 411 pp.

We used location records and annual marmot count, landscape and predator-prey data to assess recent changes in Vancouver Island marmot populations. There were probably fewer than 150 marmots in 1997, with 90% distributed south of Alberni Inlet and the remainder on or near Mount Washington. This represents a 60% decline in numbers during the past decade and a similar reduction in geographic range in the last several decades. Forestry was associated with profound structural changes in the largest remaining metapopulation. Half of the world's M. vancouverensis were living in clearcuts in 1997, compared to ~25% in the mid 1980s and none prior to high elevation logging that began in the late 1960s. Adult population trends and per capita birth rates were not correlated among natural and clearcut habitats. Probable adult numbers in natural habitats were correlated with deer abundance and extent of old-growth forests (P<0.001) and negatively associated with cougar abundance (P<0.05). Adult numbers in clearcuts were not correlated with potential clearcut habitat availability or deer abundance. Some curious results were obtained. Probable adult numbers in natural habitats were positively associated with wolf abundance (P<0.05) while numbers in clearcuts were positively associated with cougar abundance (P<0.05). Results suggest that several environmental factors influence M. vancouverensis and that natural and clearcut colonies respond differently.

NOTE: The full text of the paper is in *.pdf format here.

Blumstein, D.T., J.C. Daniel and A.A. Bryant. 2001. Antipredator behavior of Vancouver Island marmots: using congeners to evaluate abilities of a critically endangered mammal. Ethology. 107: 1-14.

Behavioral comparisons between endangered species and their congeners may provide valuable data with which to test ideas about declining populations or the future direction of recovery efforts. We considered the case of the highly endangered Vancouver Island marmot (Marmota vancouverensis). Predation is a current source of mortality, and inadequate antipredator behavior could have profound ramifications for the future success of reintroductions. We tested whether M. vancouverensis antipredator behavior was unusual or "deficient" by quantifying it and comparing it to 13 other marmot species. We found no evidence that Vancouver Island marmots were unwary. If anything the converse was true. Vancouver Island marmots were responsive and vigilant towards real and simulated predatory threats. They dug numerous escape burrows that reduced the likelihood of predation. Our results have several implications for future recovery efforts, one of which was to establish "baseline" flight-response targets that captive-bred Vancouver Island marmots will have to meet or exceed prior to release into predator-rich environments.

Bryant, A.A. 2000. Relative importance of episodic versus chronic mortality in the decline of Vancouver Island marmots (Marmota vancouverensis). Pages 189-195 in Darling, L.M. (editor): Proceedings of a conference on the biology and management of species and habitats at risk. Volume I. Proceedings, Biology and Conservation of Habitats and Species at Risk Conference (Kamloops, BC, Feb. 15-19 1999). British Columbia Ministry of Environment, Lands and Parks, and University College of the Caribou. 472 pp.

I used population count data collected from 1979–1998 to evaluate the relative importance of “chronic” versus “episodic” mortality patterns in Vancouver Island marmots (Marmota vancouverensis). I hypothesized that some factors (e.g., gradual vegetation change, forestry effects, or predation) should produce chronic patterns of mortality, and others (disease and weather) should produce episodic patterns. A few colonies had consistently low survival. These results are consistent with a hypothesis of poor quality “sink” habitats that are maintained by immigration from nearby “sources.” However, most colonies had distinct episodes of high mortality, and these appear to be the primary cause of recent population declines. Spatial and temporal patterns of survival are consistent with a hypothesis of disease outbreak or increased hunting effort by predators within a small geographic area. The impact of both factors was probably exacerbated by forestry activities. Results underscore the precarious status of this endangered mammal and illustrate the value of carefully designed annual population surveys.

Bryant, A.A. 1998. Metapopulation ecology of Vancouver Island marmots (Marmota vancouverensis). Ph.D. dissertation, University of Victoria (Victoria, B.C.) 125 pp.

Vancouver Island marmots (M. vancouverensis) rank among the world's most critically endangered mammals. There were probably fewer than 100 marmots in 1998, with 90% distributed south of Alberni Inlet, and the remainder on or near Mount Washington. This represents a 60-70% decline in numbers during the past 10 years, and a considerably reduced geographic range during the past several decades.

I used data from marked animals, radio-telemetry and population counts to test whether population dynamics were consistent with predictions made under five hypotheses: habitat tracking, sink-connectivity, weather, predators and disease. Estimates of demographic rates from intensive mark-recapture work and population counts were generally consistent, although estimation of adult survival from counts was problematic because of the difficulty of distinguishing surviving marmots from immigrants. There was no apparent influence of mark-recapture on survival or reproduction, and intensively studied colonies showed similar dynamics to colonies that were visited infrequently.

There was little evidence for habitat tracking in natural habitats. Few colonies showed chronically low reproduction or survival, which would be the predicted result of a gradually deteriorating environment. Declines were more often abrupt and catastrophic. Marmots did not colonize clearcuts in proportion to their temporal or spatial availability, and ultimately colonized only a minuscule fraction of the potential habitat. However, marmots already inhabiting clearcuts represent a special case of habitat tracking; survival rates were significantly lower at clearcuts of more advanced seral age (i.e., >11 years after harvest).

Evidence for source-sink and landscape connectivity processes was relatively strong. Marmots inhabiting clearcuts had chronically lower survival rates (by 5-10%). Per female reproductive contribution in clearcuts was half that of females inhabiting natural environments. However not all clearcuts acted as sinks, or acted as sinks in all years. Colonizations of clearcuts were spatially concentrated and none occurred at distances greater that 5 km from an existing natural colony. Apparent adult survival was significantly associated with isolation but juvenile survival was not, which is consistent with the prediction that isolated colonies should receive fewer immigrants. However the spatial pattern of extinctions was unexpected. Isolated and closely-clustered colonies had similar probabilities of extinction.

Weather significantly influenced marmot survival and reproduction but explained only small amounts of variation. Survival was significantly associated with rainfall, temperature and snowpack depth. Reproduction was negatively associated with snowpack and temperature. Slope aspect was significantly associated with survival, perhaps suggesting the importance of snowmelt patterns. Natural and clearcut colonies responded differently to weather.

Indices of wolf and cougar abundance were inconsistent and probably do not reflect true population sizes. Deer abundance was weakly associated with marmot survival in natural habitats, which could suggest switching of predator hunting effort. Marmot survival was spatially correlated, which is consistent with the idea that a few individual predators may focus hunting efforts at adjacent colonies. Field observations and radio-telemetry corroborated the importance of predators. In natural habitats, disappearances were uniformly distributed throughout summer, as predicted. In clearcuts, disappearances were more heavily skewed towards late summer, suggesting that winter mortality was more important.

Spatial correlation of survival is also consistent with the disease hypothesis. Survival was lower in colonies with high relative density of adults, which is a predicted result given the prediction of increased risk of disease transmission. The incidence of high mortality events increased during the 1990s, and the degree of spatial correlation also increased despite a more fragmented population structure. These trends are consistent with a hypothesis of a new disease organism or increased risk of infection.

Forestry appears to be the primary cause of recent population dynamics in the Nanaimo Lakes region. Logging reduced overall marmot survival, inhibited their ability to re-colonize sites, and concentrated the population, making colonies more susceptible to predators and disease. The prognosis for continued survival remains hopeful provided that current plans for captive-breeding and reintroduction are pursued aggressively.

Bryant, A.A. 1997. Updated status report for the Vancouver Island Marmot (Marmota vancouverensis) in Canada. Committee on the Status of Endangered Wildlife in Canada (COSEWIC, Ottawa, Ontario).

DESCRIPTION: The Vancouver Island marmot (Marmota vancouverensis), like other members of the genus, is fossorial, herbivorous and hibernates during winter. M. vancouverensis differs from other species in karyotype, skull characteristics, pelage and behaviour. It is similar to other alpine-dwelling marmots in its slow maturation, long life span, and complex social organization. M. vancouverensis persists despite a small and fragmented natural habitat base. It exhibits a "metapopulation" structure. The entire population consists of small colonies that occasionally form and become extinct.

DISTRIBUTION: M. vancouverensis is endemic to Vancouver Island, British Columbia. The current population is concentrated within 5 adjacent watersheds on south-central Vancouver Island. Even within this area the population is extremely localized; >65% of marmots live on 4 mountains in the central 40 kmē portion of their current range. Palaeontological and archaeological records indicate that M. vancouverensis enjoyed a broader distribution in the recent geological past.

HISTORIC RECORDS: Historic records suggest that marmots disappeared from some areas quite recently (10-30 years ago).

PROTECTION: M. vancouverensis is listed as endangered under the B.C. Wildlife Act (1980). It is also listed as endangered by the Committee on the Status of Endangered Wildlife in Canada, the U.S. Endangered Species Act and the International Union for the Conservation of Nature. Most colonies occur on privately owned lands. Two marmot habitats are legally protected (combined area of <400 ha).

POPULATION SIZE AND TRENDS: The current population contains 150-200 individuals. This represents a 50-60% decline in numbers during the past 10 years. Concomitant with this has been local extinction of several colonies during this period, including some which typically contained >10 adults.

HABITAT: Vancouver Island marmots require three essential habitat features: 1) grasses and forbs to eat, 2) colluvial soil structure for construction of overnight and overwintering burrows, and 3) microclimatic conditions that permit summer foraging, thermoregulation, and successful hibernation. Most marmots are found between 1000 and 1400 metres in elevation, and on south to west-facing slopes. Habitat scarcity is the fundamental reason for the rarity of M. vancouverensis.

BIOLOGY: M. vancouverensis is among the most social of marmots. They live in colonies which contain fewer than 5 adults on average. Females are capable of breeding at age 3, but most animals do not breed until age 4. Young marmots disperse at age 2 or later; dispersal is fundamental to maintaining metapopulation structure.

LIMITING FACTORS: The essential short-term problem is low adult and juvenile survival. Predators and unsuccessful hibernation are the principal causes of mortality. Both factors are exacerbated by the restricted range. Reproductive rates are apparently stable. There is no evidence of inbreeding depression or disease. Long-term problems probably include reduced long-distance dispersal (altered landscape connectivity caused by logging, together with reduced survival in logged habitats), and climatic/vegetation change (tree invasion of sub-alpine meadows). The question of why marmots no longer inhabit some areas is of fundamental importance. If climatic change is principally responsible, efforts to re-establish colonies will fail and there may be little that managers can do to enhance marmot populations. Alternatively, if human-caused alteration of landscape connectivity is the problem, then reintroductions should allow recovery of the species within a reasonable time period.

SPECIAL SIGNIFICANCE OF THE SPECIES: Marmota vancouverensis is one of only five endemic mammals in Canada. It is the only endemic mammal species which appears on the COSEWIC endangered list.

RECOMMENDATIONS/MANAGEMENT OPTIONS: Recovery Plan objectives have not been met. The current "eggs in one basket" distribution is highly dangerous. Planned recovery activities (research, captive-breeding, and reintroductions) should be pursued vigorously, with the objective of increasing numbers and distribution as speedily as possible.

EVALUATION: Recommended status is ENDANGERED.

Bryant, A.A. 1996. Demography of Vancouver Island Marmots (Marmota vancouverensis) in natural and clearcut environments. Pages 157-168 in LeBerre, M., R. Ramousse and L. Le Guelte (Editors): Biodiversity in Marmots. International Marmot Network (Moscow-Lyon).

Vancouver Island Marmots (Marmota vancouverensis: Swarth) normally inhabit sub-alpine meadows at 1000-1400 metres elevation. In recent years marmots colonized habitats created by clearcut logging of forests above 700 metres in elevation, but disappeared from some natural habitats. The current population is small (100-200 individuals) and highly concentrated. M. vancouverensis exhibits low reproductive rates, with small litters ( mean= 3.36, SD = 0.83, n = 36), late sexual maturity ( age at first reproduction mean= 4.00, SD = 0.82, n = 13) and a lengthy non-reproductive interval between litters ( mean = 1.83 years, SD = 0.76, n = 6). Predation and unsuccessful hibernation are the most important causes of mortality. Marmots inhabiting recently logged habitats produce fewer young and show significantly lower survival rates. Clearcut habitats may act as population "sinks" by consuming more marmots than they produce. Forestry may ultimately slow or prevent recolonization of some historic habitats.

NOTE: the full text of this document (in French and English in *html format ) is available here courtesy of The International Marmot Network.

Bryant, A.A., and D.W. Janz. 1996. Distribution and abundance of Vancouver Island Marmots (Marmota vancouverensis). Canadian Journal of Zoology. 74: 667-677.

We analyzed historic records and annual count data to assess the population status of Vancouver Island marmots (Marmota vancouverensis). Since 1972, marmots were found at 47 sites on 15 mountains. All but 2 colonies were located within 5 adjacent watersheds on south-central Vancouver Island. Counts underestimated actual marmot abundance. For most site-year combinations, observers probably counted 66-78% of adults, and 75-89% of juveniles. Reproductive colonies typically contained fewer than 5 adults ( mean= 3.86, SE = 0.61, n=34). Most animals were found at elevations above 1000 metres (81%), on south to west-facing slopes (74%). After 1981, marmots colonized 11 habitats created by logging of forests above 700 metres. Numbers of adults were above average (134-147%) during the early 1980s, and near or below average since 1990 (58-99%). The current (1995) population contains 100 to 200 animals, including 50-100 animals in logged habitats. M. vancouverensis is rare primarily because of the small size and patchy distribution of natural sub-alpine meadows on Vancouver Island. The species is apparently adapted to a metapopulation lifestyle, in which a network of small colonies exhibit population fluctuations, local extinctions, and recolonizations over time.

Bryant, A.A. 1996. Reproduction and persistence of Vancouver Island Marmots (Marmota vancouverensis) in natural and logged habitats. Canadian Journal of Zoology. 74: 678-687.

I tagged and monitored Vancouver Island marmots (Marmota vancouverensis) to investigate demographic trends among colonies inhabiting natural subalpine meadows and recently logged habitats. M. vancouverensis exhibits low reproductive rates, with litter sizes of 2 to 5 ( mean = 3.36, SD = 0.83, n=36). Females are capable of breeding at age 3, but most animals did not breed until age 4 ( mean = 4.00, SD = 0.82, n=13), and displayed a non-reproductive interval of at least 1 year between litters ( mean = 1.83, SD = 0.76, n=6). Persistence of marmots was higher at natural sites than logged areas (65% versus 48%). Maximum female age was 9 in natural habitats and 5 in clearcuts. No adult female inhabiting a clearcut (n=14) produced more than a single litter, while 5 of 14 females in natural habitats produced 11 litters. Net reproductive value of clearcut colonies was less than half that of natural colonies (Ro = 0.25 versus 0.72). Recently logged habitats may act as a demographic "sink" by consuming more dispersers than they produce, and therefore impede the recolonization of distant natural habitats.

Bryant, A.A. 1990. Genetic variability and minimum viable populations in the Vancouver Island marmot (Marmota vancouverensis). M.E.Des. Thesis, University of Calgary (Calgary, Alta.). 101 pp.

From 1987 through 1989 I studied four colonies of Vancouver Island marmots (Marmota vancouverensis) to assess genetic variability and population viability in this species. Six family groups at two natural colonies remained remarkably stable throughout the study. Seven family groups at two logging-slash colonies displayed greater turnover of individuals, and comparatively short-term use of burrows. Females produced average litters of 3.2 young (n=13) every second year, although one bred in consecutive years. Litters of four were more common in "slash" colonies. M. vancouverensis appears to be essentially monogamous, and in other respects exhibits a social structure similar to that of M. olympus. Reproductive and survivorship rates varied dramatically with year, family group, and colony. Marmots using established burrow systems in natural habitats did comparatively well; marmots using new burrow complexes did either very well or very poorly. Most mortality apparently occurred during winter hibernation. Sampled M. vancouverensis (n=44) were neither genetically destitute nor highly inbred. Electrophoresis revealed levels of genetic variability comparable to M. flaviventris and M. monax (n=22 scorable loci, estimated % polymorphic loci P=0.18, average expected heterozygosity H=0.073). Small but significant genetic differences were found between two colonies less than 20 kilometres apart, illustrating the importance of founder effects and infrequent dispersal. Effective population size Ne of the known population is close to 50 (estimates of 34.6 to 64.4).

M. vancouverensis is well-adapted to a "meta-population" lifestyle, in which a patchwork of colonies experience periodic extinctions and recolonizations. Small colonies of M. vancouverensis are vulnerable to extinction through random demographic and environmental events. Most known colonies are small. The entire population inhabits a geographically confined area, is insufficient to maintain long-term evolutionary potential (Ne=500), and is very close to the size necessary to prevent short-term loss of genetic variability through inbreeding and drift (Ne=50). The full effects of human-caused landscape alteration on marmots are not yet understood: I hypothesize that logging-slash may provide attractive summer habitat but poor conditions for successful hibernation, and may therefore act as a "sink" for dispersing marmots from higher-elevation natural colonies.

I conclude that the known population of M. vancouverensis is not "viable" using existing criteria. Long-term survival of M. vancouverensis requires that additional meta-populations be found or established, and that adequate gene flow between individual colonies be maintained. A three-pronged recovery plan is proposed. Objective #1 is to maintain current numbers and distribution, and to answer basic questions of population biology. Objective #2 is to establish a second meta-population of approximately 200 animals. At this time the species should be downlisted to "threatened" status. Objective #3 is to establish a third meta-population (of approximately 200 animals), at which time the species should be downlisted to "vulnerable" status. Additional research (on hibernacula, dispersal, and survivorship) and inventory efforts are needed. Discovery of new meta-populations could dramatically reduce the need for recovery efforts, but is unlikely.

Heard, D.C. 1977. The behaviour of Vancouver Island marmots (Marmota vancouverensis). M.Sc. Thesis, University of British Columbia (Vancouver, BC). 129 pp.

I studied the social behaviour of the Vancouver Island marmot, Marmota vancouverensis, during the summers of 1973 and 1974. Virtually nothing was known about the behaviour of this species at the outset of this study. Barash (1973b, 1974a) suggested that the social behaviour and social organization of marmot species was determined by the severity of the environment (the vegetative growing season) and its effect on the growth rate of marmots. He predicted that marmot species living in short growing season environments would decrease as the growing season increased. The objective of this study was to test this hypothesis by observing the social behaviour of Vancouver Island marmots and comparing this to the length of the vegetative growing season.

M. vancouverensis is endemic to Vancouver Island, British Columbia. The original colonizers of this species probably crossed to Vancouver Island via land connections that existed during the Illinoian glacial period, approximately 100,000 years ago, and survived subsequent glacial maxima on nunataks and coastal refugia or both. Vancouver Island marmots have been isolated from mainland forms for a length of time (10,000 to 100,000 years) sufficient to show specific evolutionary adaptations to their Vancouver Island environment.

Vancouver Island marmots live in small colonies in the subalpine parkland. Social groups consisted of one adult male, one adult female, and variable numbers of two-year-olds, yearlings, and infants. Social groups were highly integrated with a large amount of communication occurring among colony members. Alarm calls were given in response to potential predators and could be heard over the whole colony. Short whistles were given in response to aerial predators (e.g. eagles) and long whistles were given in response to terrestrial predators (e.g. black bears). Both calls are narrow bandwidth sounds, a characteristic that makes them difficult to locate. The most common social behaviors that occurred among colony members was a nose touching behaviour termed greeting. All age-sex classes of Vancouver Island marmots engaged in greetings as well as other social behaviour patterns in about the same proportions.

The vegetative growing season experienced by Vancouver Island marmots was approximately the same as that of M. flaviventris but the social behaviour of Vancouver Island marmots most closely resembled M. olympus, a species living where the growing season is much shorter. On this basis I rejected Barash's hypothesis that the length of the vegetative growing season is sufficient to account for the variability that Barash observed among marmot species. I suggest that vegetative growing season not be used as an index of growth rate but that the time required to reach adult size be measured directly. The degree of social tolerance is positively correlated with the length of time required to reach maturity.

Janz, D.W. 1982. Management of an endangered species: the Vancouver Island marmot. Pages 310-318 in Association of Zoological and Parks and Aquariums Regional Conference Proceedings. (Penticton, BC).

The Vancouver Island marmot (Marmota vancouverensis) Swarth 1911, one of only two species found entirely within Canada, is endemic to Vancouver Island, British Columbia. It was officially designated as an endangered species in March 1980. This recent status resulted from increased public interest and recognition that this species inhabits a very localized ecological niche; steep, south-facing talus and meadow slopes within the subalpine and alpine biogeoclimatic zones along the Vancouver Island insular mountain range.

The Vancouver Island marmot is ecologically similar to other alpine marmots (M. caligata, M. olympus, M. browerii) as reflected by general behaviour, ectoparasites (Heard 1977) and karyotype (Rausch and Rausch 1971). It differs in skull characteristics (Howell 1915) and the dark chocolate brown coloration of the new pelage. The contrasting white coloration of the muzzle, forehead and breast is also distinctive. Colonization of Vancouver Island by marmots is speculated to have occurred during the Illinoian glacial period (100,000 B.P.), with subsequent ecological divergence from the ancestral M. caligata stock (Heard 1977). The restricted habitat, relatively low numbers, and general biology of this species provide challenging opportunities for management and conservation measures.

Janz, D., Blumensaat, C., Dawe, N.K., Harper, B., Leigh-Spencer, S., Munro, W., and Nagorsen, D. 1994. National Recovery Plan for the Vancouver Island Marmot. Report No. 10. Recovery of Nationally Endangered Wildlife Committee, Ottawa.

The Vancouver Island marmot (Marmota vancouverensis) is the only endemic mammal species in Canada that has been listed as "endangered" either by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC) or by any provincial or territorial government. Surveys suggest one metapopulation of 200-300 individuals concentrated in the Nanaimo-Cowichan Lake region. Data on historical distribution and abundance are limited, but marmots have apparently disappeared from some parts of Vancouver Island. Causes are unknown. In 1988 a Recovery Team was established to prepare an action plan that, when implemented, would result in populations of sufficient size and distribution to remove the Vancouver Island marmot from the endangered list. Population objectives are based on the need to prevent inbreeding, maintain long-term genetic variability, and reduce the vulnerability of marmot colonies to extinction through random environmental events. Additional inventory and research activities are essential, but translocation is the most important tool through which recovery objectives can be achieved. The team recommends a population objective of 400 to 600 marmots dispersed in three meta-populations on Vancouver Island. Research, public education and funding requirements are integral components of the recovery plan.

Janz, D.W., A.A. Bryant, N.K. Dawe, H. Schwantje, B. Harper, D. Nagorsen, D. Doyle, M. deLaronde, D. Fraser, D. Lindsay, S. Leigh-Spencer, R. McLaughlin and R. Simmons. 2000. National Recovery Plan for the Vancouver Island Marmot: 2000 Update. Recovery of Nationally Endangered Wildlife Committee, Ottawa.

The purpose of this document is to reassess the goals, objectives and tasks of the initial National Recovery Plan for the Vancouver Island Marmot (Janz et al. 1994), and provide an overview of changes needed to achieve down-listing of Marmota vancouverensis from endangered status.

The original recovery goal of 400-600 marmots dispersed in three metapopulations on Vancouver Island has not changed and remains justifiable on geographic, habitat, genetic and demographic grounds.

New data have clarified past and present marmot distribution and abundance. Inventory techniques are now properly developed and the population status of this animal is well known compared to most other species at risk in British Columbia.

Within the “core” metapopulation south of Alberni Inlet, populations have declined by approximately 60% in the last decade. Marmots disappeared from the western Strathcona metapopulation within the last several decades, and the Forbidden Plateau metapopulation is now represented only by small colonies on Mount Washington. The entire population of the species was estimated at fewer than 100 individuals in 1998, of which >50% live in recently logged habitats. The spatial structure of colonies has changed in response to logging of high elevation (>700 m) forests. Additional colonies will probably continue to be formed and found, but it is unlikely that significant populations remain undiscovered.

It is difficult to determine why marmots disappeared from areas north of Alberni Inlet because so few historical (1900 to present) population data exist. Contributing factors may include weather, predators, changing patterns of climate, predation, disease, hunting by humans, and reduced landscape connectivity. Empirical evidence for any of these processes is weak. Apart from concluding that post-glacial forest succession has generally reduced the amount of potential marmot habitat, we know only that disappearances occurred relatively recently.

South of Alberni Inlet, forestry has produced dramatic effects on populations. Survival of marmots is lower in clearcuts and logging has apparently inhibited dispersal movements by providing “easy” alternative places in which to settle. The most important result of forestry was to concentrate the population, thereby increasing the risk of mortality from other factors.

Wolves, cougars and golden eagles prey upon marmots. Radio-telemetry indicates that predation has played an important role at some colonies. The significance of parasites and infectious disease remains unclear although mortality has been associated with some parasitic and bacterial infections. Survival data are consistent with a hypothesis of localized mortality factors such as disease or hunting patterns by individual predators. Mark-recapture work suggests that most mortality occurs during winter hibernation, particularly in clearcuts. Weather plays a role but explains only a small amount of the variation in survival rates. There is no evidence to suggest that reproductive rates have declined. Survival rates have declined and the frequency of high-mortality episodes has increased.

Most research objectives contained in the 1994 Recovery Plan have been met although population objectives have not. Population distribution, trends, and ecology are now reasonably well understood. Health issues constitute the most important unanswered research questions. Progress has been made towards characterizing potential reintroduction habitats although more work is required. With a handful of exceptions, additional habitat protection or habitat manipulation is not required. Experience on Vancouver Island and elsewhere supports the belief that reintroduction presents a realistic management tool. Substantial progress has been made towards increased public awareness, funding and political support.

Changes to the 1994 recovery plan
Much of the initial plan was focused on activities designed to determine population trends and answer basic ecological questions. Many relevant questions are now answered. The challenge now is to get on with the job of implementing the Plan, and raising the necessary financial support to do so.
The updated recovery plan is based on four premises.

  1. It is doubtful that significant new populations will be found north of Alberni Inlet although that possibility exists.
  2. South of Alberni Inlet, it appears unlikely that marmot populations will suddenly rebound of their own accord.
  3. Another population expansion in the Nanaimo Lakes metapopulation such as occurred during the early 1980s would probably not result in increased geographic distribution (although it would give the Recovery Team additional options).
  4. Captive-breeding combined with reintroductions presents the best hope of increasing populations within a reasonable period of time.

At least seven of the world’s 14 marmot species (M. bobac, M. baibacina, M. menzbieri, M. marmota, M. monax, M. flaviventris, M. broweri) have been successfully reared in captivity. Reintroductions using both captive-reared and wild-captured marmots have been successful although some individual releases failed.

Experience from western Europe suggests that repeated reintroductions based on annual releases of ~20 individuals will work. The mathematics of marmot reproductive biology indicate that this will require maintenance of 40-80 marmots in captivity for a period of 5-15 years.

Recovery: the next 5 years
The next five years will require that the Team invest heavily in several broad areas.

A. Population restoration
Captive breeding
a. Zoo-based programs
b. Vancouver Island facility
Reintroductions
a. Experimental transplants
b. Operational transplants
Planning
a. Captive breeding plan
b. Reintroduction plan
c. Contingency plan

B. Monitoring and research
Monitoring
a. Non-intensive population counts
b. Intensive mark-recapture
c. Radio-telemetry
Research
a. Disease, parasites and health
b. Nutrition
c. Habitat
d. Behavior
e. Genetics

   C. Habitat protection and manipulation
Protection
a. Haley Lake Ecological Reserve
b. Other habitats
Manipulation
a. Clearcut habitats
b. Natural meadows
c. Predator-prey management

D. Fund raising and communications
Fund raising
a. Prime funders
b. Secondary funders
Communications
a. Communications plan

E. Management issues
Project management
a. Marmot Recovery Team
b. Marmot Recovery Foundation
c. "Friends of the marmot" Committee

Just as the future of M. vancouverensis is precarious by virtue of small numbers and confined distribution, eventual success of recovery efforts will be limited by money and personnel. Recovery is probably ecologically feasible but will require substantial financial, political and scientific investments together with a revised organizational structure.

NOTE: The complete document is available on-line (*.pdf format) courtesy of Environment Canada. Click here for the English version, or here for the French version.

Karels, T. J., Bryant, A. A. and Hik, D. S. 2004. Comparison of discriminant function and classification tree analyses for age classification of marmots. Oikos. 105: 575-587.

We evaluated the predictive power of two classification techniques, one parametric - discriminant function analysis (DFA) and the other non-parametric - classification and regression tree analysis (CART), in order to provide a non-subjective quantitative method of determining age class in Vancouver Island marmots (Marmota vancouverensis) and hoary marmots (Marmota caligata). For both techniques we used morphological measurements of known-age male and female marmots from two independent population studies to build and test predictive models of age class. Both techniques had high predictive power (69-86%) for both sexes and both species. Overall, the two methods performed identically with 81% correct classification. DFA was marginally better at discriminating among older more challenging age classes compared to CART. However, in our test samples, cases with missing values in any of the discriminant variables were deleted and hence unclassified by DFA, whereas CART used values from closely correlated variables to substitute for the missing values. Therefore, overall, CART performed better (CART 81% vs. DFA 76%) because of its ability to classify incomplete cases. Correct classification rates were approximately 10% higher for hoary marmots than for Vancouver Island marmots, a result that could be attributed to different sets of morphological measurements. Zygomatic arch breadth measured in hoary marmots was the most important predictor of age class in both sexes using both classification techniques. We recommend that CART analysis be performed on datasets with incomplete records and used as a variable screening tool prior to DFA on more complete datasets.

Laroque, C.P., D.H. Lewis and D.J. Smith. 2001. Treeline dynamics on southern Vancouver Island, British Columbia. Western Geography. 10/11: 47-63.

This paper describes the nature of treeline dynamics and upper-elevation tree establishment patterns on southern Vancouver Island, British Columbia. We examined tree growth, climate and seedling relationships using standard dendrochronological approaches. Our data suggest that this habitat has experienced species-specific pulses of tree establishment that have had a major impact on the character of the local treeline boundaries. The stem data collected within quadrats at Gemini Mountain and Haley Bowl show that seedling establishment within the last three centuries was episodic and linked to historical climate patterns. Successful mountain hemlock establishment in this setting is restricted to periods characterized by either cool summers and shallow winter snowpacks, or warmer than normal summers and moderately deep snowpacks. The establishment of amabilis and subalpine fir seedlings appears restricted to intervals with cool growing seasons and moderately deep seasonal snowpacks. Episodic seedling establishment in the 20th century has resulted in a gradual infilling of the local tree-line and the development of a more structured parkland belt that is expected to have habitat implications for the endangered Vancouver Island marmot.

Lichota, G.B., M. McAdie, and P.S. Ross. 2004. Endangered Vancouver Island marmots (Marmota vancouverensis): sentinels of atmospherically delivered contaminants to British Columbia, Canada. Environmental Toxicology and Chemistry. 23: 402-407.

We characterized legacy and new contaminants in the highly endangered Vancouver Island (British Columbia, Canada) marmot and found generally low blood and fat concentrations of a complex mixture of pesticides, polychlorinated biphenyls (PCBs), -dibenzo-p-dioxins (PCDDs), -dibenzofurans (PCDFs), polybrominated biphenyls (PBBs), polybrominated diphenyl ethers (PBDEs), and polychlorinated naphthalenes (PCNs) in their tissues. The dominance of the more volatile a-hexachlorocyclohexane (HCH) and hexachlorobenzene (HCB) pesticides and the lesser chlorinated PCB congeners suggests that atmospheric processes largely explain the contamination of this high-altitude herbivore.

Mace, T.F., and C.D. Shepard. 1981. Helminths of a Vancouver Island marmot Marmota vancouverensis, with a description of Diandrya vancouverensis sp. nov. (Cestoda: Anoplocephalidae). Canadian Journal of Zoology. 59: 790-792.

A female Vancouver Island marmot, Marmota vancouverensis Swarth 1911, collected on Green Mountain, Vancouver Island, British Columbia, was infected with the nematode Baylisascaris laevis and anoplocephalid tapeworms of the genus Diandrya. These worms differed from D. composita, the only species of Diandrya previously recorded, and are described as Diandrya vancouverensis sp. nov. The dimensions of reproductive organs and the presence of a neck and unarmed cirrus are characters distinctive to D. vancouverensis.

Martell, A.M. and R.J. Milko. 1986. Seasonal diets of Vancouver Island marmots. Canadian Field-Naturalist. 100: 241-245.

The diet of Vancouver Island Marmots (Marmota vancouverensis) was examined by fecal analysis at three subalpine colonies on four occasions between late May and mid-September. Two additional, high-elevation colonies were examined in late May only. Diets were similar among colonies but showed seasonal shifts. Diets were more variable among sites in late May than later in the summer, possibly reflecting site-specific availability at a time when food supply is limited. In late May Phlox diffusa and Carex sp. were important at all colonies but Danthonia intermedia, Lupinus latifolius, and sedge glumes were dominant at specific colonies. Later in the summer Lupinus and Eriophyllum lanatum were the major foods at all colonies. As summer progressed the proportion of graminoids in the diet declined and the proportion of forbs increased. Vancouver Island Marmots in the subalpine appear to specialize on relatively few food species.

Milko, R.J. 1984. Vegetation and foraging ecology of the Vancouver Island marmot (Marmota vancouverensis). M.Sc. Thesis, University of Victoria (Victoria, BC). 127 pp.

The foraging ecology of the Vancouver Island Marmot (Marmota vancouverensis) was studied in the field to determine its degree of patch-type habitat selection and diet breadth. Vegetation analysis of the intensively studied Haley Lake site and two additional sites produced six community types in the summer. In addition, three vegetation types were classified from four sites in the spring, a period when early stages of plant development precluded recognition of plant community types derived from the late summer. These types provided a framework for analysis of patch type selection. Combining cover values of plant species from taxa which were difficult to identify did not affect the classification. The six community types are: Phlox-moss, Anaphalis-Aster, Ribes-Heuchera, Pteridium aquilinum, Senecio-Veratrum and Vaccinium-Carex.

The Haley Lake site showed sharply delineated plant communities, while Bell Creek, the other floristically similar low elevation site, formed more of a vegetational continuum. Vegetation similarities allowed examination and comparison of marmot patch type selection at these two sites. Gemini Peak, the high elevation site, was floristically distinct and showed a more advanced stage of plant succession affecting its relatively homogenous meadow vegetation.

The plant communities studied were compared with those described for other subalpine regions of the Pacific Northwest and explanations for the described vegetation patterns are proposed. In the spring, patch-type selection was found with a low variability between sites. In the summer, the highest selection was for the Anaphalis-Aster community type, most notably at the site with the most distinct patch definition. In the spring, four plant species accounted for 87.2% of the marmot's diet. Mean grazing of these four species was constant in all patch types independent of their mean availability, although examination of those species in individual sampling quadrats showed a variable response of use to availability. Except Phlox diffusa, species availability was low. Incidence of use indicated the strongest selection for grasses. Diet composition shifted from graminoids at early phenological stages, to forbs, with a continuous summer preference for five plant species. Results indicated a strong conformity to herbivore diet selection models.

Patch type selection in spring or summer was not predictable by the relative abundance of the preferred forage species. Analyses suggested that the risk of predation in tall vegetation most strongly influence patch type selection, although the benefits of greater food abundance appeared to balance the cost of risk. Distance from burrows and a high frequency of Golden Eagle presence are proposed as risk factors affecting patch type selection in the spring. Plant succession and other aspects of the vegetation are discussed with respect to the possible constraints they may have on the marmot population.

Munro, W.T, D.W. Janz, V. Heinsalu and G.W. Smith. 1985. The Vancouver Island Marmot: status and management plan. B.C. Ministry of Environment Wildlife Bulletin No. B-39 (Victoria, BC). 23 pp.}

The Vancouver Island marmot (Marmota vancouverensis) is the rarest of all the North American species of marmot; it exists solely on Vancouver Island. In March 1980, it was officially designated an endangered species by Order in Council by the Province of British Columbia. Active management of the Vancover Island marmot has occurred only recently. Information on distribution, population trends, biology, and habitat requirements initiated in the 1970's is receiving greater attention in the 1980's. Surveys in recent years and observations of some of the well-known colonies indicate that the Vancouver Island marmot population has increased in both numbers and distribution since the early 1970s.

The ultimate goal of the Vancouver Island marmot management plan is to establish and maintai n the population of Vancouver Island marmots at a level and distribution that provides a reasonable likelihood of long-term survival of the species. Specific objectives of the management plan are:

  1. to ensure that six distinct reproducing populations are in existence by 1985 and ten by 1990.
  2. to secure habitat for key marmot colonies and prevent alienation and alteration of known marmot habitat,
  3. to maintain one small captive breeding colony,
  4. to encourage and support approved scientific research, and
  5. to encourage public participation in various aspects of the program and to keep the public informed of progress.

Implementation of the activities associated with each objective are detailed in the plan. The plan will be modified periodically in response to increasing knowledge, implementation progress, availability of funding, and management priorities.

NOTE: the full text of this document (in *pdf. format) is available on-line here courtesy of the B.C. Provincial Government.

Nagorsen, D.W, G. Keddie and T. Luszcz. 1996. Vancouver Island marmot bones from subalpine caves: archaeological and biological significance. B.C. Parks Occasional Paper #4. Ministry of Environment, Lands and Parks (Victoria, BC).

Since 1985, faunal remains of the Vancouver Island marmot have been discovered in four high elevation cave sites: Clayoquot Plateau, Mariner Mountain, Limestone Mountain and the Golden Hinde. Two sites are in Strathcona Provincial Park and a third is in Clayoquot Plateau Provincial Park. Cut marks on bones and artifacts recovered in Mariner Mountain cave indicate that the remains are the result of human hunting. Radiocarbon dating revealed that these sites are prehistoric ranging from 830-2630 years ago. The faunal remains provide additional evidence for a range decline in the Vancouver Island marmot. No marmots live in the vicinity of the cave sites today and three sites are peripheral to the present range. Although black bear, black-tailed deer, marten, and red squirrel are represented in the faunal remains, the predominance of Vancouver Island marmots suggest that aboriginal peoples traveled to these remote mountainous areas to hunt marmots. We summarize the analysis of faunal remains and review the implications for Vancouver Island marmot biogeography and conservation, and aboriginal cultural history. Recommendations for future research in BC Parks and managing these cave sites are presented.

NOTE: the full text of this document (in *pdf. format) is available on-line here courtesy of the B.C. Provincial Government.

Other useful references (no abstract available)

Nagorsen, D.W. 1987. Marmota vancouverensis. Mammalian Species. 270:1-5.

Swarth, H.S. 1911. Two new species of marmots from Northwestern America. University of California Publications in Zoology. 7:201-204.

Swarth, H.S. 1912. Report on a collection of birds and mammals from Vancouver Island. University of California Publications in Zoology. 10:1-124.

Back to Science pages