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Variability in Calanus spp. abundance on fine- to mesoscales in an Arctic fjord: implications for little auk feeding
(Journal article; Tidsskriftartikkel; Peer reviewed, 2014)
Moonlight Drives Ocean-Scale Mass Vertical Migration of Zooplankton during the Arctic Winter
(Journal article; Tidsskriftartikkel; Peer reviewed, 2016-01-07)
In extreme high-latitude marine environments that
are without solar illumination in winter, light-mediated
patterns of biological migration have historically
been considered non-existent [1]. However, diel vertical
migration (DVM) of zooplankton has been shown
to occur even during the darkest part of the polar
night, when illumination levels are exceptionally low
[2, 3]. This paradox is, as ...
AUV-based acoustic observations of the distribution and patchiness of pelagic scattering layers during midnight sun
(Journal article; Tidsskriftartikkel; Peer reviewed, 2016-09-28)
An autonomous underwater vehicle (AUV) carrying 614 kHz RDI acoustic doppler current profilers (ADCPs) was deployed at four locations over the West Spitsbergen outer shelf in July 2010. The backscatter signal recorded by the ADCPs was extracted and analysed to investigate the vertical distribution and patchiness of pelagic organisms during midnight sun. At the northernmost locations (Norskebanken ...
Genetic diversity and connectivity within Mytilus spp. in the subarctic and Arctic
(Journal article; Tidsskriftartikkel; Peer reviewed, 2016-10-26)
Climate changes in the Arctic are predicted to alter distributions of marine species. However, such changes are difficult to quantify because information on present species distribution and the genetic variation within species is lacking or poorly examined. Blue mussels, Mytilus spp., are ecosystem engineers in the coastal zone globally. To improve knowledge of distribution and genetic structure of ...
In the darkness of the polar night, scallops keep on a steady rhythm
(Journal article; Tidsskriftartikkel; Peer reviewed, 2016)
Although the prevailing paradigm has held that the polar night is a period of biological quiescence, recent studies have detected noticeable activity levels in marine organisms. In this study, we investigated the circadian rhythm of the scallop Chlamys islandica by continuously recording the animal’s behaviour over 3 years in the Arctic (Svalbard). Our results showed that a circadian rhythm persists ...
Seasonal vertical strategies in a high-Arctic coastal zooplankton community
(Journal article; Tidsskriftartikkel; Peer reviewed, 2016-08-18)
We studied the larger (>1000 µm) size fraction of zooplankton in an Arctic coastal
water community in Billefjorden, Svalbard (78°40’ N), Norway, in order to describe seasonal vertical
distributions of the dominant taxa in relation to environmental variability. Calanus spp.
numerically dominated the herbivores; Aglantha digitale, Mertensia ovum, Beroë cucumis, and
Parasagitta elegans were the ...
The Atlantic spiny lumpsucker Eumicrotremus spinosus: life history traits and the seemingly unlikely interaction with the pelagic amphipod Themisto libellula
(Journal article; Tidsskriftartikkel; Peer reviewed, 2013)
During a cruise to Svalbard in September 2012 a unique collection of the little
known but widely distributed Atlantic spiny lumpsucker (Eumicrotremus spinosus) was
made in the Hinlopen Strait. A total of 140 individuals (36–101mm total length) were col−
lected using a bottom trawl. All individuals were sexed and 26 of these were also analysed
for gonadosomatic index (GSI), hepatosomatic index ...
Aspects of the life history of the Atlantic poacher, Leptagonus decagonus, in Svalbard waters
(Journal article; Tidsskriftartikkel; Peer reviewed, 2015-03-25)
The aim of the study is to describe aspects of the life history of the Atlantic poacher (Leptagonus decagonus) obtained during early October 2010 and late September 2011 from the Hinlopen Strait, located between Nordaustlandet and the Spitsbergen Archipelago. Length was measured for 142 individuals, and 82 out of these were weighed, sexed and the age in years determined. The sex distribution in the ...
The adaptive significance of chromatophores in the Arctic under-ice amphipod Apherusa glacialis
(Journal article; Tidsskriftartikkel; Peer reviewed, 2011)
Solar radiation is a crucial factor governing biological processes in polar habitats. Containing harmful ultraviolet radiation (UVR), it can pose a threat for organisms inhabiting surface waters of polar oceans. The present study investigated the physiological color change in the obligate sympagic amphipod Apherusa glacialis mediated by red-brown chromatophores, which cover the body and internal ...
Introduction to the special issue on polar night studies conducted onboard RV Helmer Hanssen in the Svalbard area
(Journal article; Tidsskriftartikkel; Peer reviewed, 2014)