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Seasonal difference in temporal transferability of an ecological model: near-term predictions of lemming outbreak abundances
(Journal article; Tidsskriftartikkel; Peer reviewed, 2018-10-15)
Ecological models have been criticized for a lack of validation of their temporal transferability. Here we
answer this call by investigating the temporal transferability of a dynamic state-space model developed
to estimate season-dependent biotic and climatic predictors of spatial variability in outbreak abundance
of the Norwegian lemming. Modelled summer and winter dynamics parametrized by spatial ...
Community-wide mesocarnivore response to partial ungulate migration
(Journal article; Tidsskriftartikkel; Peer reviewed, 2014)
Changed Arctic-alpine food web interactions under rapid climate warming: implication for ptarmigan research
(Journal article; Tidsskriftartikkel; Peer reviewed, 2017-06-05)
Ptarmigan are herbivorous birds that are year-round residents of alpine and arctic ecosystems — presently subjected to the most rapid climate warming on earth. Yet, compared to other bird taxa there has been little climate impact research on ptarmigan. Ptarmigan population dynamics, in particular in the sub/low-arctic, appears to be strongly influenced by complex interactions with a suite of ...
Ecosystem drivers of an Arctic fox population at the western fringe of the Eurasian Arctic
(Journal article; Tidsskriftartikkel; Peer reviewed, 2017-08-16)
The distribution of traditional breeding dens on the Varanger Peninsula (70–71°N) in northernmost
Fennoscandia indicates that this area once harboured a large Arctic fox population.
Early 20th century naturalists regarded the coastal tundra of the Fennoscandian Low Arctic to
be a stronghold for the species. At the start of our research in 2004, however, the local Arctic
fox population was ...
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, ...
Transferability of biotic interactions: temporal consistency of arctic plant-rodent relationships is poor
(Journal article; Tidsskriftartikkel; Peer reviewed, 2018-09-17)
Variability in biotic interaction strength is an integral part of food web functioning.
However, the consequences of the spatial and temporal variability of biotic interactions
are poorly known, in particular for predicting species abundance and distribution.
The amplitude of rodent population cycles (i.e., peak-phase abundances) has
been hypothesized to be determined by vegetation properties ...
Collapse of an arctic bird community resulting from ungulate-induced loss of erect shrubs
(Journal article; Tidsskriftartikkel; Peer reviewed, 2012)
Rapid, but contrasting, changes in the extent of erect thicket-forming shrubs is presently seen in the Arctic, either resulting from a warmer climate (increasing extent) or intensified herbivory (decreasing extent). We investigated the impact of loss of willow shrubs on a bird community in arctic riparian sediment plains in northern Norway subject to varying intensities of reindeer browsing. In ...
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 ...
The importance of willow thickets for ptarmigan and hares in shrub tundra : the more the better?
(Journal article; Tidsskriftartikkel; Peer reviewed, 2012)