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Arctic greening from warming promotes declines in caribou populations
(Journal article; Tidsskriftartikkel; Peer reviewed, 2017-04-26)
The migratory tundra caribou herds in North America follow decadal population cycles, and browsing from abundant
caribou could be expected to counteract the current climate-driven expansion of shrubs in the circumpolar tundra
biome. We demonstrate that the sea ice cover in the Arctic Ocean has provided a strong signal for climate-induced
changes on the adjacent caribou summer ranges, outperforming ...
A Novel Brominated Alkaloid Securidine A, Isolated from the Marine Bryozoan Securiflustra securifrons
(Journal article; Tidsskriftartikkel; Peer reviewed, 2017-07-23)
A novel brominated alkaloid, Securidine A, was isolated from the cold water marine bryozoan Securiflustra securifrons. Securidine A was isolated using semi-preparative HPLC, and the structure was elucidated by spectroscopic methods. The isolated Securidine A was tested for cytotoxic, antibacterial, and anti-diabetic activities as well as for its potential for inhibition of biofilm formation. No ...
Elevationally biased avian predation as a contributor to the spatial distribution of geometrid moth outbreaks in sub-arctic mountain birch forest
(Journal article; Tidsskriftartikkel; Peer reviewed, 2017-04-03)
1. Population dynamics and interactions that vary over a species’ range are
of particular importance in the context of latitudinal clines in biological diversity.Winter
moth (Operophtera brumata) and autumnal moth (Epirrita autumnata) are two species
of eruptive geometrids that vary widely in outbreak tendency over their range, which
generally increases from south to north and with elevation.
2. ...
Upward nitrate flux and downward particulate organic carbon flux under contrasting situations of stratification and turbulent mixing in an Arctic shelf sea
(Journal article; Tidsskriftartikkel; Peer reviewed, 2017-08-02)
Increased sea ice melt alters vertical surface-mixing processes in Arctic seas. More melt water strengthens the stratification, but an absent ice cover also exposes the uppermost part of the water column to wind-induced mixing processes. We conducted a field study in the Barents Sea, an Arctic shelf sea, to examine the effects of stratification and vertical mixing processes on 1) the upward nitrate ...
Seasonality of vertical flux and sinking particle characteristics in an ice-free high arctic fjord—Different from subarctic fjords?
(Journal article; Tidsskriftartikkel; Peer reviewed, 2015-10-23)
The arctic Adventfjorden (78°N, 15°E, Svalbard) used to be seasonally ice-covered but has mostly been ice-free
since 2007. We used this ice-free arctic fjord as a model area to investigate (1) how the vertical
fl
ux of biomass
(chlorophyll
a
and particulate organic carbon, POC) follows the seasonality of suspended material, (2) how sink-
ing particle characteristics change seasonally and ...
Turbulent heat and momentum fluxes in the upper ocean under Arctic sea ice
(Journal article; Tidsskriftartikkel; Peer reviewed, 2017-02-25)
We report observations of heat and momentum fluxes measured in the ice-ocean boundary layer from four drift stations between January and June 2015, covering from the typical Arctic basin conditions in the Nansen Basin to energetic spots of interaction with the warm Atlantic Water branches near the Yermak Plateau and over the North Spitsbergen slope. A wide range of oceanic turbulent heat flux values ...
Carbon, Nitrogen and Sulphur isotopic fractionation in captive juvenile hooded seal (Cystophora cristata): application for diet analysis
(Journal article; Tidsskriftartikkel; Peer reviewed, 2017-08-15)
<p><i>Rationale</i>: Intrinsic biogeochemical markers, such as stable isotope ratios of carbon, nitrogen and sulphur, are increasingly used to trace the trophic ecology of marine top predators. However, insufficient knowledge of fractionation processes in tissues continues to hamper the use of these markers.</p>
<p><i>Methods</i>: We performed a controlled feeding experiment with eight juvenile ...
Cold seawater induces early sexual developmental stages in the BPG axis of European eel males
(Journal article; Tidsskriftartikkel; Peer reviewed, 2019-07-22)
<i>Background</i>: The impossibility of closing the life cycle of the European eel (<i>Anguilla anguilla</i>) in captivity troubles the
future of this critically endangered species. In addition, the European eel is a highly valued and demanded resource,
thus the successful closing of its life cycle would have a substantial economic and ecological impact. With the aim of
obtaining the highest ...
Impacts of Early Life Stress on the Methylome and Transcriptome of Atlantic Salmon
(Journal article; Tidsskriftartikkel; Peer reviewed, 2017-07-10)
Exposure to environmental stressors during early-life stages can change the rate and timing of various
developmental processes. Epigenetic marks affecting transcriptional regulation can be altered by such
environmental stimuli. To assess how stress might affect the methylome and transcriptome in salmon,
fish were treated using cold-shock and air-exposure from the eye-stage until start-feeding. ...
Fish silage hydrolysates: Not only a feed nutrient, but also a useful feed additive
(Journal article; Tidsskriftartikkel; Peer reviewed, 2017-06-06)
Background:<br>
Processing of fish and shellfish may result in substantial amounts of by-products and unless they can be used as food, the most realistic option in most cases is the production of preserved feed nutrients. If large volumes are available, reduction to fishmeal and fish oil is the preferred technology. However, fresh by-products are most often available in insufficient quantities ...