Now showing items 1-20 of 363

    • Temporal variation in marine mammal species assemblage at South Orkney Islands revealed through passive acoustic data from 2016 and 2017 

      Åsvestad, Linn (Master thesis; Mastergradsoppgave, 2022-06-02)
      Passive Acoustic Monitoring (PAM) is a non-invasive method providing high- resolution information about marine mammal acoustic presence. Multi-species PAM studies can increase our understanding of temporal changes in species diversity and assemblage and is especially useful in remote areas such as the Southern Ocean. This study was based on 16 months of acoustic data spanning two austral autumns and ...
    • From Trash to Treasure: The use of Lumpfish (Cyclopterus lumpus) as feed for Red King Crab (Paralithodes camtschaticus) 

      Conradi-Larsen, Tora (Master thesis; Mastergradsoppgave, 2023-05-15)
      This thesis explores the potential of using farmed lumpfish (Cyclopterus lumpus), discarded from Atlantic salmon (Salmo salar L.) aquaculture industry, as a sustainable feed for juvenile red king crabs (Paralithodes camtschaticus). The red king crab has successfully established a self-sustaining population in the Barents Sea. With the red king crab being a large generalist predator, its impact on ...
    • Ingestion of Tyre Crumb Rubber and Uptake of Associated Contaminants in Marine Invertebrates (Pandalus borealis) and Fish (Cyclopterus lumpus) – An Experimental Exposure Study 

      Hägg, Fanny (Master thesis; Mastergradsoppgave, 2022-05-15)
      Crumb rubber (CR) produced from end of life vehicle tires is widely used on artificial sports fields and to create urban artificial surfaces. It is also used as a surrogate for tyre wear particles in experimental studies simulating the behaviour and effects of car tyre particles in the environment. It is known to contain a wide range of organic chemicals and metals, some of which are only just being ...
    • Aggregative response in white-tailed eagles- an initial study of the terrestrial implications of invasive Pacific pink salmons (Oncorhynchus gorbuscha) in northern Norway. 

      Bonde, Bror Mathias (Master thesis; Mastergradsoppgave, 2023-05-15)
      Abstract The spawning population of invasive Pacific pink salmon (Oncorhynchus gorbuscha) has only continued to increase in the river systems on the Varanger peninsula in Norway, causing concerns across institutional boundaries and management communities. So far, the Norwegian research efforts on Pacific pink salmon have been centred on consequential effects in marine- and freshwater ecosystems, ...
    • Exposure of marine invertebrates to car tire rubber: Uptake of rubber particles and related organic chemicals 

      Galtung, Kristin (Master thesis; Mastergradsoppgave, 2023-05-15)
      Car tire rubber particles (CTRPs) are a major source of microplastic pollution to the environment, originating from abrasion during driving or the use of crumb rubber granulates made of discarded tires. However, large knowledge gaps remain regarding the distribution and presence of CTRPs in marine environments and interaction with marine organisms. The aims of this thesis were to investigate the ...
    • Isolation and Characterization of Bacteriophages from the Arctic 

      Hosen, Md Sabuj (Master thesis; Mastergradsoppgave, 2023-05-14)
      Bacteriophages are viruses that specifically infect bacteria. These obligate intracellular parasites are Earth's most copious, ubiquitous, and genetically diverse (unexplored) biological entities. Organisms in the Arctic environment constantly experience extreme conditions, therefore life in the Arctic evolved different specialized strategies and molecules to survive which offers huge opportunities ...
    • Diel activity rhythms in wild songbirds in the Subarctic 

      Staurland, Marie Østlid (Master thesis; Mastergradsoppgave, 2024-02-15)
      The highly rhythmic environment caused by the rotation of the earth has driven the evolution of an intrinsic timekeeping mechanism in most organisms known as circadian clocks. As climate change drives the expansion of southern species into northern latitudes, their circadian clocks are challenged by the novel light conditions they encounter. In contrast to the clear day and night in southern latitudes, ...
    • To keep or not to keep track of time in eternal sunshine? Diel activity patterns of Svalbard arthropods during polar day 

      Huntsaar, Maria (Master thesis; Mastergradsoppgave, 2024-02-16)
      Organisms on Earth are exposed to cyclic changes in environmental variables due to Earth’s rotation around it’s axis. As a response, many organisms adapt their behaviour in a rhythmic manner, which is often cued by 24h light-dark cycles. However, in the Arctic, traditional 24h light- dark cycle cues do not exist for long periods at the time. Arthropods play an important role in the high latitude ...
    • Establishment of killer whale cell cultures and their responses to pollutant exposure 

      Bjørneset, Juni (Master thesis; Mastergradsoppgave, 2022-03-15)
      The cosmopolitan apex predator killer whale (Orcinus orca) is one of the species worldwide with the highest levels of persistent organic pollutants (POPs) in their tissues. The knowledge of how POPs may affect the species is limited, likely due to the ethical, legal, and practical challenges of researching toxicology on free-ranging marine mammals. The use of in vitro models has proved to be a ...
    • Role of the lactate receptor HCAR1 as part of neural adaptations to hypoxia in hooded seals (Cystophora cristata) 

      Torppa, Sara (Master thesis; Mastergradsoppgave, 2023-11-15)
      To maintain normal neuronal function, the mammalian brain requires a constant supply of energy. The deep-diving hooded seal (<i>Cystophora cristata</i>) brain exhibits remarkable tolerance to extreme hypoxia, presumably involving a reduction in brain activity to lower energy demand. Thus, some neurons, circuits or even regions in the seal’s brain presumably display a neural protective shutdown ...
    • Human responses to year-round lighting using Google Trends to investigate seasonality in activity patterns and libido 

      Starck, Hedda Lærum (Master thesis; Mastergradsoppgave, 2023-11-16)
      Seasonal rhythms in humans are fascinating but studying them is inherently challenging due to the need for data that covers multiple years. Due to the experimental obstacles, it remains debated whether humans exhibit seasonal fluctuations in aspects such as activity levels and libido. To approach these topics through indirect digital measures, this thesis used multi-year data from Google Trends ...
    • Reindeer diseases associated with supplementary feeding in Norway and Sweden - A questionnaire-based survey 

      Josteinsdottir, Alfa Bachmann (Master thesis; Mastergradsoppgave, 2021-11-15)
      Climatic and anthropogenic factors are increasingly affecting reindeer husbandry in Norway and Sweden. The potential health risks associated with a warming climate, and the necessity to avoid starvation by providing supplementary feed to semi-domesticated reindeer, need to be explored and identified. A questionnaire-based survey among reindeer herders was conducted, containing questions about the ...
    • Thermal properties of arctic fox fur and the effect of fur lice infestation. 

      Henriksson, Anna Galina (Master thesis; Mastergradsoppgave, 2023-11-15)
      In 2019, a new species of sucking louse was observed in arctic foxes (Vulpes lagopus) on Svalbard and Northern Canada. Abnormal patterns of fur loss, inconsistent with normal moult, were observed across the neck, shoulders and back, raising concerns as to how the animals would cope with damaged fur during the cold Arctic winter. This study investigates the impact of these lice on Svalbard arctic ...
    • Impact of autopolyploidy on leaf structure and photosynthesis in Saxifraga oppositifolia L. 

      Hjelle, Simen Salomonsen (Master thesis; Mastergradsoppgave, 2023-12-01)
      Polyploidization can be a rapid path to speciation and is considered an important evolutionary mechanism. Some predict that all plants have undergone a polyploidization event during their evolutionary history, and the frequency of polyploid species increases with latitude. The Arctic-Alpine Saxifraga oppositifolia, an autopolyploid, has two polyploids that have successfully established themselves ...
    • Seasonal Variations in Vertical Flux of particulate matter and composition in the Northern Barents Sea 

      Hussain, Tassawer (Master thesis; Mastergradsoppgave, 2023-11-15)
      The Barents Sea is an inflow shelf sea in the Arctic Ocean which experiences climate change consequently reduction in the sea ice extent thereby significantly impacting its ecological importance. This study investigates seasonal variations in the vertical flux of particulate matter including both particulate organic matter (chl a) and particulate inorganic matterin the form of CaCO3 contributed by ...
    • The metabolic roles of astrocytes and neurons in the diving brain A study of the mitochondrial distribution in the brain of the hooded seal (Cystophora cristata) 

      Dötterer, Sari Elena (Master thesis; Mastergradsoppgave, 2023-11-15)
      The brain is highly dependent on oxygen for its metabolism and, in most mammals, major brain dysfunction occurs already within minutes of insufficient oxygen supply (hypoxia). Oxygen is the final electron acceptor in the electron transport system that drives the production of ATP through oxidative phosphorylation in the mitochondria. The rate at which oxidative phosphorylation produces ATP is dependent ...
    • Nutritious and delicious? A non-invasive study of food plant choices by Svalbard reindeer in Summer and late Autumn 

      Eikeland, Oline (Master thesis; Mastergradsoppgave, 2023-12-05)
      Seasonality affects growing patterns of vegetation and habitat use by herbivores. Short growing seasons make plants grow quickly through phenological stages which alters their nutrient levels and thus habitat use of herbivores that depend on energy assimilation in summer. Selective foraging that increases intake of high-quality forage can be highly advantageous and is usually a trade-off between ...
    • Drivers of mercury accumulation over the ontogeny of perch (Perca fluviatilis) in the subarctic Pasvik watercourse 

      Fredriksen, Julie (Master thesis; Mastergradsoppgave, 2023-11-15)
      Understanding drivers of mercury (Hg) accumulation in freshwater food webs is vital due to its ability to accumulate in organisms and magnify in food webs to potent levels, potentially impacting wildlife and human health. This is of particular concern in regions where fish serve as an important food source. This study explores drivers of Hg accumulation in European perch (Perca fluviatilis) across ...
    • Long-Term Effects on Somatic Growth, Life History Traits and Population Biology of Arctic Charr (Salvelinus alpinus) Following the Fish Culling Experiment in Takvatn 

      Indrebø, Synne Nan (Master thesis; Mastergradsoppgave, 2023-11-14)
      Stunting in fish populations is a special case of density-dependent growth characterized by old slow-growing individuals with low recreational and resource use value. The phenomenon is commonly observed in lacustrine populations of Arctic charr (Salvelinus alpinus) in temperate regions. In Takvatn, a subarctic lake in northern Norway, stunted growth of Arctic charr was attributed to food shortage ...
    • Drivers of an unexpected unimodal vertical pattern in size distribution of intertidal blue mussels (Mytilus spp.) 

      Sellæg, Victoria Eggen (Master thesis; Mastergradsoppgave, 2023-11-14)
      Blue mussels (Mytilus spp.) are important ecosystem bioengineers and provide numerous of ecosystem services. They are found worldwide, but face a global population decline for unclear reasons in many regions. A pilot study in the subarctic rocky intertidal shore in Northern Norway revealed an unexpected unimodal pattern in the body size of blue mussels along a vertical transect from low to high ...