Artikler, rapporter og annet (arktisk og marin biologi): Nye registreringer
Viser treff 1121-1140 av 1637
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Area protection may reduce salmon louse infection risk to wild salmonids
(Journal article; Tidsskriftartikkel; Peer reviewed, 2011-05-30)ABSTRACT: Salmon louse <i>Lepeophtheirus salmonis</i> Krøyer infection levels in both wild sea trout <i>Salmo trutta</i> L. and sentinel Atlantic salmon <i>Salmo salar</i> L. smolts were investigated inside and outside a temporary protected zone with limits on fish farming in the intensively farmed Romsdalsfjord system. Wild sea trout outside the protected zone had higher prevalence and significantly ... -
Growth and development of skeletal anomalies in diploid and triploid Atlantic salmon (Salmo salar) fed phosphorus-rich diets with fish meal and hydrolyzed fish protein
(Journal article; Tidsskriftartikkel; Peer reviewed, 2018-03-22)Diploid and triploid Atlantic salmon, <i>Salmo salar</i> were fed high-protein, phosphorus-rich diets (56–60% protein; ca 18g phosphorus kg<sup>-1</sup> diet) whilst being reared at low temperature from start-feeding until parr-smolt transformation. Performances of salmon fed diets based on fish meal (STD) or a mix of fishmeal and hydrolysed fish proteins (HFM) as the major protein sources were ... -
The distribution of the fathead sculpin species Cottunculus subspinosus Jensen, 1902
(Journal article; Tidsskriftartikkel; Peer reviewed, 2018-04-13)The range of the rarely caught fathead sculpin species <i>Cottunculus subspinosus</i> has been considered restricted to the waters off East Greenland and Northeast Iceland. For the first time the species is recorded from the east side of the Norwegian Sea, and also it is found further north in the Greenland Sea than previously known. Mapping all the corroborated specimens known indicates that the ... -
Temporally stable population-specific differences in run timing of one-sea-winter Atlantic salmon returning to a large river system
(Journal article; Tidsskriftartikkel; Peer reviewed, 2010-12-06)The understanding of migration patterns can significantly contribute to conservation and management. The spawning migrations of Atlantic salmon (<i>Salmo salar</i>) cover thousands of kilometers from the feeding areas at sea to their natal rivers to reproduce. Migrating salmon are exposed to intensive harvest, but little is known of the population‐specific differences in migration behavior. In this ... -
Inter-laboratory testing of the effect of DNA blocking reagent G2 on DNA extraction from low-biomass clay samples
(Journal article; Tidsskriftartikkel; Peer reviewed, 2018-04-09)Here we show that a commercial blocking reagent (G2) based on modified eukaryotic DNA significantly improved DNA extraction efficiency. We subjected G2 to an inter-laboratory testing, where DNA was extracted from the same clay subsoil using the same batch of kits. The inter-laboratory extraction campaign revealed large variation among the participating laboratories, but the reagent increased the ... -
Size at maturity and molting probability across latitude in female Cancer pagurus
(Journal article; Tidsskriftartikkel; Peer reviewed, 2018-04-11)Edible crab, <i>Cancer pagurus</i>, is a valuable North Atlantic fishery resource distributed from Morocco to northern Norway, covering a wide range of temperatures and other oceanographic variables. Knowledge on how local environmental conditions affect life history traits like maturity and growth in this species is however lacking, despite its importance in science-based management. Through analyses ... -
Temporal variability in surface water pCO2 in Adventfjorden (West Spitsbergen) with emphasis on physical and biogeochemical drivers
(Journal article; Tidsskriftartikkel; Peer reviewed, 2018-06-26)Seasonal and interannual variability in surface water partial pressure of CO<sub>2</sub> (<i>p</i>CO2) and air‐sea CO<sub>2</sub> fluxes from a West Spitsbergen fjord (IsA Station, Adventfjorden) are presented, and the associated driving forces are evaluated. Marine CO<sub>2</sub> system data together with temperature, salinity, and nutrients, were collected at the IsA Station between March 2015 and ... -
Mandibular shape in farmed Arctic foxes (Vulpes lagopus) exposed to persistent organic pollutants
(Journal article; Tidsskriftartikkel; Peer reviewed, 2018-07-26)We investigated if dietary exposure to persistent organic pollutants (POPs) affect mandibular asymmetry and periodontal disease in paired male-siblings of Arctic foxes (<i>Vulpes lagopus</i>). During ontogeny, one group of siblings was exposed to the complexed POP mixture in naturally contaminated minke whale (<i>Balaenoptere acutorostarta</i>) blubber (n = 10), while another group was given wet ... -
The serostatus of Brucella spp., Chlamydia abortus, Coxiella burnetii and Neospora caninum in cattle in three cantons in Bosnia and Herzegovina
(Journal article; Tidsskriftartikkel; Peer reviewed, 2018-02-02)Dairy production in Bosnia and Herzegovina exhibits limited productivity, which may partly, be explained by extensive reproductive problems of non-infectious and infectious origin. Brucella spp., Chlamydia abortus, Coxiella burnetii and Neospora caninum are common infectious causes of decreased reproductive outcomes in cattle worldwide. Little is, however, known about the disease status of herds ... -
New Species of Saprobic Labyrinthulea (=Labyrinthulomycota) and the Erection of a gen. nov. to Resolve Molecular Polyphyly within the Aplanochytrids
(Journal article; Tidsskriftartikkel; Peer reviewed, 2017-12-19)A culture of a unicellular heterotrophic eukaryote was established from pollen‐baited seawater acquired from the nearshore environment in Tromsø, Norway. Light microscopy revealed the production of ectoplasmic nets and reproduction by biflagellated zoospores, as well as binary division. After culturing and subsequent nucleotide extraction, database queries of the isolate's 18S small ribosomal subunit ... -
Stay or go – how topographic complexity influences alpine plant population and community responses to climate change
(Journal article; Tidsskriftartikkel; Peer reviewed, 2017-11-11)In the face of climate change, populations have two survival options − they can remain in situ and tolerate the new climatic conditions (“stay”), or they can move to track their climatic niches (“go”). For sessile and small-stature organisms like alpine plants, staying requires broad climatic tolerances, realized niche shifts due to changing biotic interactions, acclimation through plasticity, or ... -
Use of an Autonomous Surface Vehicle reveals small-scale diel vertical migrations of zooplankton and susceptibility to light pollution under low solar irradiance
(Journal article; Tidsskriftartikkel; Peer reviewed, 2018-01-10)Light is a major cue for nearly all life on Earth. However, most of our knowledge concerning the importance of light is based on organisms’ response to light during daytime, including the dusk and dawn phase. When it is dark, light is most often considered as pollution, with increasing appreciation of its negative ecological effects. Using an Autonomous Surface Vehicle fitted with a hyperspectral ... -
Histopathological characterisation of retinal lesions associated to Diplostomum species (Platyhelminthes: Trematoda) infection in polymorphic Arctic charr Salvelinus alpinus
(Journal article; Tidsskriftartikkel; Peer reviewed, 2018)The eye represents an immune privileged organ where parasites can escape host reactions. This study provides the first systematic evidence of the pathology associated with <i>Diplostomum</i> sp. infection in the eye retina of fish (i.e. Arctic charr). Histological sections showed that the trematodes caused mechanical disengagement between the retinal pigmentary epithelium and the neurosensory retina, ... -
Spawning behavior of Arctic charr (Salvelinus alpinus): Spawning synchrony, vibrational communication, and mate guarding
(Journal article; Tidsskriftartikkel; Peer reviewed, 2018-07-20)A mismatch in synchrony between male and female gamete release in external ferti - lizers can result in reduced or failed fertilization, sperm competition, and reduced paternity. In Arctic charr ( Salvelinus alpinus ), males can adopt either a guard or sneak tactic resulting in both pre- and postcopulatory ... -
The longer the better: the effect of substrate on sessile biota in Arctic kelp forests
(Journal article; Tidsskriftartikkel; Peer reviewed, 2018-02-02)Kelps are ecosystem engineers and thus enhance biodiversity and subsidize food webs in nearshore areas. Numerous studies describing diversity and abundance of biota associated with kelp have focused on sub-tropical and temperate waters while kelp forests at high latitudes, where kelp is predicted to expand in distribution, remain mostly unexplored. Kelp forests contribute significantly to regional ... -
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 ... -
An Arctic predator–prey system in flux: climate change impacts on coastal space use by polar bears and ringed seals
(Journal article; Tidsskriftartikkel; Peer reviewed, 2017-04-17)<p>1. Climate change is impacting different species at different rates, leading to alterations in biological interactions with ramifications for wider ecosystem functioning. Understanding these alterations can help improve predictive capacity and inform management efforts designed to mitigate against negative impacts.</p> <p>2. We investigated how the movement and space use patterns of polar bears ... -
Between classical and critical geopolitics in a changing Arctic
(Journal article; Tidsskriftartikkel; Peer reviewed, 2018-03-26)Puzzled by how geographical changes in the Arctic might cause changes in state behavior the authors of this article have been inspired to return to the roots of geopolitical reasoning. By combining insights from the intellectual roots of the geopolitical tradition with empirical data on geographical changes as well as policy changes in the Arctic today, we investigate the degree to which geopolitics, ... -
High-density cultivation of terrestrial Nostoc strains leads to reprogramming of secondary metabolome
(Journal article; Tidsskriftartikkel; Peer reviewed, 2017-09-22)Terrestrial symbiotic cyanobacteria of the genus <i>Nostoc</i> exhibit a large potential for the production of bioactive natural products of the nonribosomal peptide, polyketide, and ribosomal peptide classes, and yet most of the biosynthetic gene clusters are silent under conventional cultivation conditions. In the present study, we utilized a high-density cultivation approach recently developed ... -
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 ...