Now showing items 11-16 of 16
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 ...
The database of the PREDICTS (Projecting Responses of Ecological Diversity In Changing Terrestrial Systems) project
(Journal article; Tidsskriftartikkel; Peer reviewed, 2016-12-10)
The PREDICTS project—Projecting Responses of Ecological Diversity In Changing Terrestrial Systems (www.predicts.org.uk)—has collated from published studies a large, reasonably representative database of comparable samples of biodiversity from multiple sites that differ in the nature or intensity of human impacts relating to land use. We have used this evidence base to develop global and regional ...
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 ...
Not only mosses: lemming winter diets as described by DNA metabarcoding
(Journal article; Tidsskriftartikkel; Peer reviewed, 2017-04-01)
The temporal dynamics of most tundra food webs are shaped by the cyclic population dynamics of lemmings. While processes during winter may be behind the recent disruptions of lemming cycles, lemming winter ecology is poorly known. We present here the first DNA metabarcoding data on the winter diet of Norwegian lemmings (Lemmus lemmus), based on feces collected after a winter of population ...
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 ...