Now showing items 31-40 of 63
Numerical responses of saproxylic beetles to rapid increases in dead wood availability following geometrid moth outbreaks in sub-arctic mountain birch forest
(Journal article; Tidsskriftartikkel; Peer reviewed, 2014)
Saproxylic insects play an important part in decomposing dead wood in healthy forest ecosystems, but little is known about their role in the aftermath of large-scale forest mortality caused by pest insect outbreaks. We used window traps to study short-term changes in the abundance and community structure of saproxylic beetles following extensive mortality of mountain birch in sub-arctic northern ...
Resistance of a sub-arctic bird community to severe forest damage caused by geometrid moth outbreaks
(Journal article; Tidsskriftartikkel; Peer reviewed, 2015-05-01)
Outbreaks by geometrid moths periodically cause mass mortality of trees and state changes in understorey vegetation in sub-arctic mountain birch forest in northern Scandinavia. In order to assess the short-term impacts of such disturbance on forest bird communities, we took bird censuses in forest where almost all birch trees had been killed by moth outbreaks 2–4 years before the study and in ...
Identification and Evaluation of 21 Novel Microsatellite Markers from the Autumnal Moth (Epirrita autumnata) (Lepidoptera: Geometridae)
(Journal article; Tidsskriftartikkel; Peer reviewed, 2015-09-17)
The autumnal moth (Epirrita autumnata) is a cyclically outbreaking forest Lepidoptera with circumpolar distribution and substantial impact on Northern ecosystems. We have isolated 21 microsatellites from the species to facilitate population genetic studies of population cycles, outbreaks, and crashes. First, PCR primers and PCR conditions were developed to amplify 19 trinucleotide loci and two ...
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 ...
From individuals to population cycles: the role of extrinsic and intrinsic factors in rodent populations
(Journal article; Tidsskriftartikkel; Peer reviewed, 2016-03-28)
Rodent population cycles have fascinated scientists for a long time. Among various hypotheses, an interaction of an extrinsic factor (predation) with intrinsic factors (e.g., sociality and dispersal) was suggested to lead to the generation of population cycles. Here, we tested this hypothesis with an individual-based model fully parameterized with an exceptionally rich empirical database on vole ...
Sources of variation in small rodent trophic niche: New insights from DNA metabarcoding and stable isotope analysis
(Journal article; Tidsskriftartikkel; Peer reviewed, 2014-05-15)
Fjellrev i Finnmark : forskning og tiltak 2006
(Research report; Forskningsrapport, 2006)
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, ...
An Arctic predator–prey system in flux: climate change impacts on coastal space use by polar bears and ringed seals
(Journal article; Tidsskriftartikkel; Peer reviewed, 2017-04-17)
<p>1. Climate change is impacting different species at different rates, leading to alterations in biological interactions with ramifications for wider ecosystem functioning. Understanding these alterations can help improve predictive capacity and inform management efforts designed to mitigate against negative impacts.</p> <p>2. We investigated how the movement and space use patterns of polar bears ...
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 ...