Risk of mortality of wild salmon caused by salmon lice is used as an index for managing aquaculture production in Norway and is based on monitoring of lice attached to wild salmonids and modelled concentrations of lice larvae in fjords. Direct sampling of lice from Norwegian waters to determine concentrations has never been published scientifically and has been considered non-feasible for monitoring ...

The metabolism of the Arctic Ocean is marked by extremely pronounced seasonality and spatial heterogeneity associated with light conditions, ice cover, water masses and nutrient availability. Here we report the marine planktonic metabolic rates (net community production, gross primary production and community respiration) along three different seasons of the year, for a total of eight cruises ...

Understanding the present state and possible future scenarios of Arctic Ocean primary productivity has been hampered by the scarcity of year-round nutrient measurements. Here, the first year-long moored timeseries of near-surface nitrate concentrations in the Eastern Arctic, together with hydrography, currents and chlorophyll-a fluorescence, is reported from ...

Eastern Fram Strait and the shelf slope region north of Svalbard is dominated by the advection of warm, salty and nutrient-rich Atlantic Water (AW). This oceanic heat contributes to keeping the area relatively free of ice. The last years have seen a dramatic decrease in regional sea ice extent, which is expected to drive large increases in pelagic primary production and thereby changes in marine ...

We investigated the population dynamics of a small and little-studied harpacticoid copepod, <i>Microsetella norvegica</i>, in a sub-Arctic Norwegian fjord (Balsfjord 69°N). We sampled with a 90 μm mesh WP-2 net and a 20 L Go-Flo bottle and found that the WP-2 under-sampled all juvenile stages. The abundance and biomass were high, peaking in June with 9349 × 10-³ ind. m⁻² and ...

The marine ecosystem in Kongsfjorden (79 N), a glacial fjord in Svalbard, is to a large extent well known with regard to hydrography, mesozooplankton and higher trophic levels. Research on primary production and lower trophic levels is still scare and especially investigations from winter and spring periods. The spring bloom dynamics in Kongsfjordenwere investigated in 2002. The development in ...

While marine ecosystems in polar areas were thought to be mostly inactive during the polar night, recent observations in the Arctic highlight that dynamic biological interactions occur across all trophic levels. One particularly interesting observation made repeatedly is the occurrence of Calanus finmarchicus, a key species at the base of the food web, in the upper part of the water column in early ...

The ocean capacity to store carbon is crucial, and currently absorbs about 25% CO₂ supply to the atmosphere. The ability to store carbon has an economic value, but such estimates are not common for ocean environments, and not yet estimated for the Arctic Ocean. With the severe climatic changes in the Arctic Ocean, impacting sea ice and potentially the vertical carbon transport mechanisms, ...

<p>This study compiles colocated oceanic observations of high-resolution vertical profiles of nitrate concentration and turbulent microstructure around the Svalbard shelf slope, covering both the permanently ice-free Fram Strait and the pack ice north of Svalbard. The authors present an overview over the seasonal evolution of the distribution of nitrate and its relation to upper ocean stratification. ...