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Demersal fish assemblages in the boreo-Arctic shelf waters around Svalbard during the warm period 2007–2014
(Journal article; Tidsskriftartikkel; Peer reviewed, 2017-07-17)
The temporal and spatial resilience of abundance patterns of assemblages of organisms inhabiting transition zones between Arctic and boreal regions is an issue of concern in relation to climate change. The recognition that baseline information spanning such transition zones is required to facilitate future monitoring and assessments of temporal dynamics provided the motivation for the present study. ...
Biodiversity may wax or wane depending on metrics or taxa
(Journal article; Tidsskriftartikkel; Peer reviewed, 2018-02-20)
<i>Introduction</i>: Biodiversity changes have proven surprisingly complex to estimate and understand. While there are negative trends at a global scale such as the substantial losses of vertebrate species (1), changes at local scales may show large variation, with no clear overall trend (2, 3). Because assessing and improving the status of biodiversity are at the core of international agreements ...
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 ...
The role of a dominant predator in shaping biodiversity over space and time in a marine ecosystem
(Journal article; Tidsskriftartikkel; Peer reviewed, 2015-06-24)
Exploitation of living marine resources has resulted in major changes to populations of targeted species and functional groups of large-bodied species in the ocean. However, the effects of overfishing and collapse of large top predators on the broad-scale biodiversity of oceanic ecosystems remain largely unexplored. Populations of the Atlantic cod (Gadus morhua) were overfished and several collapsed ...
The role of predation and food limitation on claims for compensation, reindeer demography and population dynamics
(Journal article; Tidsskriftartikkel; Peer reviewed, 2014-10)
1.A major challenge in biodiversity conservation is to facilitate viable populations of large apex predators in ecosystems where they were recently driven to ecological extinction due to resource conflict with humans. 2. Monetary compensation for losses of livestock due to predation is currently a key instrument to encourage human–carnivore coexistence. However, a lack of quantitative estimates ...
Community-wide mesocarnivore response to partial ungulate migration
(Journal article; Tidsskriftartikkel; Peer reviewed, 2014)
Long-term environmental monitoring for assessment of change: measurement inconsistencies over time and potential solutions
(Journal article; Tidsskriftartikkel; Peer reviewed, 2017-10-30)
The importance of long-term environmental monitoring and research for detecting and understanding changes in ecosystems and human impacts on natural systems is widely acknowledged. Over the last decades, a number of critical components for successful long-term monitoring have been identified. One basic component is quality assurance/quality control protocols to ensure consistency and comparability ...
Effects of changing permafrost and snow conditions on tundra wildlife: critical places and times
(Journal article; Tidsskriftartikkel; Peer reviewed, 2016-12-21)
The change of water phase around 0 °C has considerable impacts on wildlife ecology because liquid and solid water strongly differ in their insulating capability, mechanical resistance, and light reflectance. Freeze and melt events thus have strong ecological relevance, particularly in the Arctic where snow and ice are omnipresent and their conditions are changing due to climate warming. We first ...
Ungulate population monitoring in an open tundra landscape: distance sampling versus total counts
(Journal article; Tidsskriftartikkel; Peer reviewed, 2017-07-27)
Researchers and wildlife managers strive for low bias and high precision (i.e. high accuracy) when estimating animal population sizes. Distance sampling is currently one of the most widely used monitoring methods. However, it relies on strict sampling designs and modeling assumptions that can be difficult to meet in the field. Here, we use data from two sub-populations of non-migratory wild Svalbard ...
Phenology and cover of plant growth forms predict herbivore habitat selection in a high latitude ecosystem
(Journal article; Tidsskriftartikkel; Peer reviewed, 2014)
The spatial and temporal distribution of forage quality is among the most central factors affecting herbivore habitat
selection. Yet, for high latitude areas, forage quantity has been found to be more important than quality. Studies on large
ungulate foraging patterns are faced with methodological challenges in both assessing animal movements at the scale of
forage distribution, and in assessing ...