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norskInstitutt for arktisk og marin biologi: Recent submissions
Now showing items 1081-1100 of 2050
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A transdisciplinary approach to Brucella in Muskoxen of the Western Canadian Arctic 1989-2016
(Journal article; Tidsskriftartikkel; Peer reviewed, 2019-08-14)Brucella serostatus was evaluated in 3189 muskoxen sampled between 1989 and 2016 from various locations of the Canadian Arctic archipelago and mainland, near the communities of Sachs Harbour and Ulukhaktok, Northwest Territories, and Cambridge Bay and Kugluktuk, Nunavut. Brucella antibodies were found only in muskoxen sampled around Cambridge Bay, both on southern Victoria Island and on the adjacent ... -
Seasonal patterns in species diversity across biomes
(Journal article; Tidsskriftartikkel; Peer reviewed, 2019-01-30)A conspicuous season–diversity relationship (SDR) can be seen in seasonal environments, often with a defined peak in active species diversity in the growing season. We ask is this a general pattern and are other patterns possible? In addition, we ask what is the ultimate cause of this pattern and can we understand it using existing ecological theory? To accomplish this task, we assembled a global ... -
Circumpolar patterns of Arctic freshwater fish biodiversity: A baseline for monitoring
(Journal article; Tidsskriftartikkel; Peer reviewed, 2019-10-01)Climate change, biological invasions, and anthropogenic disturbance pose a threat to the biodiversity and function of Arctic freshwater ecosystems. Understanding potential changes in fish species distribution and richness is necessary, given the great importance of fish to the function of freshwater ecosystems and as a resource to humans. However, information gaps limit large‐scale studies and our ... -
Widespread soil bacterium that oxidizes atmospheric methane
(Journal article; Tidsskriftartikkel; Peer reviewed, 2019-04-08)Increasing atmospheric methane concentrations contribute significantly to global warming. The only known biological sink for atmospheric methane is oxidation by methane oxidizing bacteria (MOB). Due to the lack of pure cultures, the physiology and metabolic potential of MOB that oxidize atmospheric methane remains a mystery. Here, we report on isolation and characterization of a MOB that can grow ... -
DNA double‐strand breaks in Arctic char (Salvelinus alpinus) from Bjørnøya in the Norwegian Arctic
(Journal article; Tidsskriftartikkel; Peer reviewed, 2019-07-25)High levels of organochlorine contaminants (OCs) have been found in arctic char (<i>Salvelinus alpinus</i>) from Lake Ellasjøen, Bjørnøya (Norwegian Arctic). The aim of the present study was to investigate the potential genotoxic effect of environmental organochlorine contaminant exposure in arctic char from Ellasjøen compared with arctic char from the low‐contaminated Lake Laksvatn nearby. Blood ... -
Thermal habitat of adult Atlantic salmon Salmo salar in a warming ocean
(Journal article; Tidsskriftartikkel; Peer reviewed, 2019-10-29)The year‐round thermal habitat at sea for adult Atlantic salmon <i>Salmo salar</i> (<i>n</i> = 49) from northern Norway was investigated using archival tags over a 10 year study period. During their ocean feeding migration, the fish spent 90% of the time in waters with temperatures from 1.6–8.4°C. Daily mean temperatures ranged from −0.5 to 12.9°C, with daily temperature variation up to 9.6°C. Fish ... -
Temporal trend of mercury in relation to feeding habits and food availability in arctic foxes (Vulpes lagopus) from Svalbard, Norway
(Journal article; Tidsskriftartikkel; Peer reviewed, 2019-03-20)We investigated the temporal trend of mercury (Hg) in arctic foxes from Svalbard, Norway sampled in the period 1997–2014 (<i>n</i> = 109, from 11 trapping seasons). We used linear models to investigate the effect of trapping season, feeding habits (δ<sup>13</sup>C), food availability from marine and terrestrial ecosystems (reindeer carcasses and sea ice cover), sex, age and body condition on liver ... -
Disappearing green: Shrubs decline and bryophytes increase with nine years of increased snow accumulation in the High Arctic
(Journal article; Tidsskriftartikkel; Peer reviewed, 2019-07-25)<i>Question</i> - How does increased snow depth affect plant community composition of High Arctic tundra, and can the Normalized Differential Vegetation Index (NDVI) detect induced changes?<p><p> <i>Location</i> - Adventdalen, Spitsbergen, Svalbard (78°10′ N, 16°04′ E).<p><p> <i>Methods</i> - We manipulated snow depth on the tundra using fences, resulting in <i>Deep, Medium</i>, and ... -
Feeding studies take guts - critical review and recommendations of methods for stomach contents analysis in fish
(Journal article; Tidsskriftartikkel; Peer reviewed, 2019-10-07)Studies on the feeding ecology of fish are essential for exploring and contrasting trophic interactions and population and community dynamics within and among aquatic ecosystems. In this respect, many different methods have been adopted for the analysis of fish stomach contents. No consensus has, however, been reached for a standardised methodology despite that for several decades there has been an ... -
Selective mineral transport barriers at Cuscuta-host infection sites
(Journal article; Tidsskriftartikkel; Peer reviewed, 2019-10-11)The uptake of inorganic nutrients by rootless parasitic plants, which depend on host connections for all nutrient supplies, is largely uncharted. Using X‐ray fluorescence spectroscopy (XRF), we analyzed the element composition of macro‐ and micronutrients at infection sites of the parasitic angiosperm <i>Cuscuta reflexa</i> growing on hosts of the genus <i>Pelargonium</i>. Imaging methods combining ... -
Environmental filtering and phylogenetic clustering correlate with the distribution patterns of cryptic protist species
(Journal article; Tidsskriftartikkel; Peer reviewed, 2018-01-29)The community composition of any group of organisms should theoretically be determined by a combination of assembly processes including resource partitioning, competition, environmental filtering, and phylogenetic legacy. Environmental DNA studies have revealed a huge diversity of protists in all environments, raising questions about the ecological significance of such diversity and the degree to ... -
Tipping point in plant-fungal interactions under severe drought causes abrupt rise in peatland ecosystem respiration
(Journal article; Tidsskriftartikkel; Peer reviewed, 2017-10-09)Ecosystems are increasingly prone to climate extremes, such as drought, with long‐lasting effects on both plant and soil communities and, subsequently, on carbon (C) cycling. However, recent studies underlined the strong variability in ecosystem's response to droughts, raising the issue of nonlinear responses in plant and soil communities. The conundrum is what causes ecosystems to shift in response ... -
Comparative vegetation survey with focus on cryptogamic covers in the high Arctic along two differing catenas
(Journal article; Tidsskriftartikkel; Peer reviewed, 2019-09-24)Although cryptogamic covers are important ecosystem engineers in high Arctic tundra, they were often neglected in vegetation surveys. Hence we conducted a systematic survey of cryptogamic cover and vascular plant coverage and composition at two representative, but differing Arctic sites (Ny-Ålesund, Svalbard) along catenas with a natural soil moisture gradient, and integrated these data with ... -
Discontinuity in the molecular neuroendocrine response to increasing daylengths in Ile-de-France ewes: Is transient Dio2 induction a key feature of circannual timing?
(Journal article; Tidsskriftartikkel; Peer reviewed, 2019-07-24)In mammals, melatonin is responsible for the synchronisation of seasonal cycles to the solar year. Melatonin is secreted by the pineal gland with a profile reflecting the duration of the night and acts via the pituitary pars tuberalis (PT), which in turn modulates hypothalamic thyroid hormone status via seasonal changes in the production of locally‐acting thyrotrophin. Recently, we demonstrated that, ... -
Assessing winter pasture quality in Sunnfjord wild reindeer area
(Master thesis; Mastergradsoppgave, 2019-11-30)Winter pastures are bottlenecks for population trends for wild reindeer, and the quality and availability are important parameters when managing populations. Sunnfjord, considered on of the smallest wild reindeer districts in Norway, have never had a comprehensive evaluation of accessible winter pasture within. The aim of study is to assess the quality of winter forage in all tree sub- areas within ... -
Relationship between carbon- and oxygen-based primary productivity in the Arctic Ocean, svalbard archipelago
(Journal article; Tidsskriftartikkel; Peer reviewed, 2019-08-02)Phytoplankton contribute half of the primary production (PP) in the biosphere and are the major source of energy for the Arctic Ocean ecosystem. While PP measurements are therefore fundamental to our understanding of marine biogeochemical cycling, the extent to which current methods provide a definitive estimate of this process remains uncertain given differences in their underlying approaches, and ... -
Activity patterns in mammals: Circadian dominance challenged
(Journal article; Tidsskriftartikkel; Peer reviewed, 2019-07-15)The evidence that diel patterns of physiology and behaviour in mammals are governed by circadian ‘clocks’ is based almost entirely on studies of nocturnal rodents. The emergent circadian paradigm, however, neglects the roles of energy metabolism and alimentary function (feeding and digestion) as determinants of activity pattern. The temporal control of activity varies widely across taxa, and ungulates, ... -
Seroprevalence of pestivirus in Eurasian tundra reindeer in Finland, Sweden, Norway, Iceland and Russian Federation
(Journal article; Tidsskriftartikkel; Peer reviewed, 2019-10-29)Reindeer herding is of great importance for the indigenous people of the Fennoscandia peninsula and northern Russia. There are also free-ranging feral populations of reindeer in Finland, Iceland, Norway and Russian Federation. The genus Pestivirus contains several viral species that infect ungulates and often show capacity to transmit between different host species. Sera from 520 Eurasian tundra ... -
Evidence of seawater drinking in fasting subadult hooded seals (Cystophora cristata)
(Journal article; Tidsskriftartikkel; Peer reviewed, 2019-01-29)The purpose of this study was to investigate the total water turnover rate of fasting subadult hooded seals in order to elucidate to what extent these animals rely in seawater drinking/mariposia at this life stage. Considering mariposia is important for later accurate estimations of food consumption using water turnover rate as a proxy. Five subadult hooded seals were kept fasting for 4 days in a ... -
Sinking Organic Particles in the Ocean—Flux Estimates From in situ Optical Devices
(Journal article; Tidsskriftartikkel; Peer reviewed, 2020-02-18)Optical particle measurements are emerging as an important technique for understanding the ocean carbon cycle, including contributions to estimates of their downward flux, which sequesters carbon dioxide (CO<sub>2</sub>) in the deep sea. Optical instruments can be used from ships or installed on autonomous platforms, delivering much greater spatial and temporal coverage of particles in the mesopelagic ...
