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Declining willow ptarmigan populations : the role of habitat structure and community dynamics
(Journal article; Tidsskriftartikkel; Peer reviewed, 2011)
The recent range contractions and population declines of many grouse species worldwide have been attributed to loss and fragmentation of their habitats, although the empirical evidence for the actual drivers is often weak. In case of the willow ptarmigan Lagopus lagopus in Fennoscandia, ungulate overbrowsing of willows has been hypothesized to exert such negative habitat-related impacts. Moreover, ...
Rapid, landscape scale responses in riparian tundra vegetation to exclusion of small and large mammalian herbivores
(Journal article; Tidsskriftartikkel; Peer reviewed, 2011)
Productive tundra plant communities composed of a variety of fast growing herbaceous and woody plants are likely to attract mammalian herbivores. Such vegetation is likely to respond to different-sized herbivores more rapidly than currently acknowledged from the tundra. Accentuated by currently changing populations of arctic mammals there is a need to understand impacts of different-sized herbivores ...
Population dynamics of tundra voles in relation to configuration of willow thickets in southern arctic tundra
(Journal article; Tidsskriftartikkel; Peer reviewed, 2011)
The areal extent and conWguration of thickets of
willow shrubs are currently changing in the Arctic both as an eVect of global warming and changed browsing pressure of reindeer. These changes have been predicted to impact the distribution and abundance of wildlife species relying on willow thickets as habitat. We assessed the relation between variables quantifying willow thicket configuration
and ...
Red fox takeover of arctic fox breeding den : an observation from Yamal Peninsula, Russia
(Journal article; Tidsskriftartikkel; Peer reviewed, 2011)
Here, we report from the first direct observation of a red fox (Vulpes vulpes) intrusion on an arctic fox (Vulpes lagopus) breeding den from the southern Arctic tundra of Yamal Peninsula, Russia in 2007. At the same time, as a current range retraction of the original inhabitant of the circumpolar tundra zone the arctic fox is going on, the red fox is expanding their range from the south into arctic ...
Intrapopulation variability shaping isotope discrimination and turnover : experimental evidence in Arctic Foxes
(Journal article; Tidsskriftartikkel; Peer reviewed, 2011)
Tissue-specific stable isotope signatures can provide insights into the trophic ecology of consumers and their roles in food webs. Two parameters are central for making valid inferences based on stable isotopes, isotopic discrimination (difference in isotopic ratio between consumer and its diet) and turnover time (renewal process of molecules in a given tissue usually measured when half of the tissue ...
The ghost of development past : the impact of economic security policies on Saami pastoral ecosystems
(Journal article; Tidsskriftartikkel; Peer reviewed, 2011)
To ensure economic viability over time, any efforts to meet the Millennium Development
Goals need to reconcile conservation with development interventions. Particularly, in marginal and risk prone areas erosion of resilience could make production systems more susceptible to environmental risks that compromise the economic security. By longitudinal analyses of long-term data records we investigated
the ...