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Data from: Thelomma ocellatum, a range extension to the Yukon Territory and case study in the use of molecular data to recognize asexually
- 负责人：
- DOI：
- doi:10.5061/dryad.6mp50
- 摘要：
- An unusual sterile, asexually reproducing crustose lichen was encountered during fieldwork in the Yukon Territory of Canada. Genus and family level
Data from: Continent-wide population genomic structure and phylogeography of North America’s most destructive conifer defoliator, the spruce budworm (Choristoneura fumiferana)
- 负责人：
- DOI：
- doi:10.5061/dryad.00000000k
- 摘要：
- structured subpopulations: Western (Alaska, Yukon), Central (southeastern Yukon to the Manitoba-Ontario border) and Eastern (Manitoba-Ontario border
Monitoring the relative abundance of bird and mammal species on Herschel Island
- 负责人：
- Canadian Polar Data Network (CPDN)
- 关键词：
- Yukon Abundance Birds Herschel Island Mammals Tundra International Polar Year-Arctic Wildlife Observatories Linking Vulnerable EcoSystems
- DOI：
- doi:10.5443/1731
- 摘要：
- The relative abundance of species is recorded as the number of individuals seen per hour spent in the field per observer. Each observer records daily the animal species encountered in the field and the number of individuals observed. To correct for any potential biases the activities and mode of transportation of observers are also taken into account.We also monitor the nests of bird species that are not part of our long-term monitoring and are found opportunistically, such as Canada Goose, Common Eider, Greater White-fronted Goose, Mallard, Northern Pintail, Red-throated Loon, Rock Ptarmigan and Tundra Swan.** If data are downloaded and used for analyses, it would greatly be appreciate that the principal investigator be informed.;;Purpose: Monitoring the occurence of all tundra species encountered daily.;;Summary: Not Applicable
Data from: Life-history characteristics and landscape attributes as drivers of genetic variation, gene flow and fine-scale population structure in Northern Dolly Varden (Salvelinus malma malma) in Canada
- 负责人：
- DOI：
- doi:10.5061/dryad.652vq
- 摘要：
- . Gene flow occurred primarily among Yukon North Slope populations and between sympatric anadromous and resident forms. These results were sex-dependent to som
Data from: Amplicon pyrosequencing late Pleistocene permafrost: the removal of putative contaminant sequences and small-scale reproducibility
- 负责人：
- Porter, Teresita
- DOI：
- doi:10.5061/dryad.4m7d1
- 摘要：
- and forbs during cold stages of the Pleistocene, a habitat that is restricted to isolated sites in the present-day Yukon.
Data from: Linking the wintering and breeding grounds of warblers along the Pacific Flyway
- 负责人：
- Toews, David
- DOI：
- doi:10.5061/dryad.7ft57
- 摘要：
- of North America are likely to breed at high latitudes in Alaska and the Yukon rather than in Alberta or further east. Our interpretation is that the evolution
Data from: Using experimentation to understand the 10-year snowshoe hare cycle in the boreal forest of North America
- 负责人：
- Krebs, Charles
- DOI：
- doi:10.5061/dryad.684s1
- 摘要：
- 1. Population cycles have long fascinated ecologists from the time of Charles Elton in the 1920s. The discovery of large population fluctuations in undisturbed ecosystems challenged the idea that pristine nature was in a state of balance. The 10-year cycle of snowshoe hares (Lepus americanus Erxleben) across the boreal forests of Canada and Alaska is a classic cycle, recognized by fur traders for more than 300 years. 2. Since the 1930s ecologists have investigated the mechanisms that might cause these cycles. Proposed causal mechanisms have varied from sunspots to food supplies, parasites, diseases, predation, and social behaviour. Both the birth rate and the death rate change dramatically over the cycle. Social behaviour was eliminated as a possible cause because snowshoe hares are not territorial and do not commit infanticide. 3. Since the 1960s large-scale manipulative experiments have been used to discover the major limiting factors. Food supply and predation quickly became recognized as potential key factors causing the cycle. Experiments adding food and restricting predator access to field populations have been decisive in pinpointing predation as the key mechanism causing these fluctuations. 4. The immediate cause of death of most snowshoe hares is predation by a variety of predators, including the Canada lynx (Lynx canadensis Kerr). The collapse in the reproductive rate is not due to food shortage as was originally thought, but is a result of chronic stress from predator chases. 5. Five major issues remain unresolved. First, what is the nature of the predator-induced memory that results in the prolonged low phase of the cycle? Second, why do hare cycles form a travelling wave, starting in the centre of the boreal forest in Saskatchewan and travelling across western Canada and Alaska? Third, why does the amplitude of the cycle vary greatly from one cycle to the next in the same area? Fourth, do the same mechanisms of population limitation apply to snowshoe hares in eastern North American or in similar ecosystems across Siberia? Finally, what effect will climatic warming have on all the above issues? The answers to these questions remain for future generations of biologists to determine.
Data from: Changes in behavior are unable to disrupt a trophic cascade involving a specialist herbivore and its food plant
- 负责人：
- DOI：
- doi:10.5061/dryad.vb653hv
- 摘要：
- Black brant (Branta bernicla nigricans) nesting in colonies on the Yukon–Kuskokwim Delta (YKD) in western Alaska have declined substantially (~50%) sinc
The distribution and abundance of parasites in harvested wildlife from the Canadian North : a review
- 负责人：
- 关键词：
- DOI：
- doi:10.21963/12962
- 摘要：
- on the parasites of harvested wildlife in the Canadian North including studies in the Yukon, Northwest Territories, Nunavut, northern Quebec (Nunavik
Data from: Arctic and boreal paleofire records reveal drivers of fire activity and departures from Holocene variability
- 负责人：
- DOI：
- doi:10.5061/dryad.0gb5mkkxv
- 摘要：
- of black spruce, ca. 6-4 thousand years before present (yr BP). Biomass burning also increased during warm periods, particularly in the Yukon Flats ecoregion from
