Viser treff 214-233 av 362

    • Metabolomic and genomic investigation of two North-Norwegian cyanobacterial isolates for bioprospecting of new compounds 

      Norum Kirkesæther, Ane (Master thesis; Mastergradsoppgave, 2022-02-15)
      Cyanobacteria are an excellent source of bioactive natural products that can be used in the development of new medicinal drugs. The cyanobacterial genus Nostoc have proven to be prolific producers of molecules with exciting bioactivities, including anti-bacterial, anti-fungal, and anti-cancerous. This feature combined with the Nostoc’s complex life cycle and sizeable genomes make them interesting ...
    • Metabolomic and metagenomic study of Lake Baikal diseased sponges 

      Churakova, Yelena (Master thesis; Mastergradsoppgave, 2020-08-15)
      Widespread mortality and disease are recognized as growing problems in benthic marine coral and sponge communities across the globe and despite being extensively studied, in most cases the etiology of disease remains unknown. Since 2011, sponge communities in freshwater Lake Baikal, Siberia, Russia have been affected by an unknown agent of disease, which has been causing an array of physical disease ...
    • Methane emissions from reindeer - do reindeer fed lichens emit less methane than reindeer on a pelleted feed diet? 

      Hansen, Kia Krarup (Master thesis; Mastergradsoppgave, 2012-11-18)
      Microbial fermentation in the world domesticated ruminant populations is thought to be responsible for as much as 13.5-33% of the global anthropogenic methane (CH4) emissions (World Resources Institute 2005, EPA 2004, Bodas et al., 2012). However, methane also represents a loss of 2-15% of the gross energy intake in these animals (Blaxter and Clapperton 1965, Holter and Young 1992, Johnson and Ward ...
    • Microbial responses to warming and seasonal temperature changes in sub-Arctic forest and grassland soils 

      Ahlers, Laureen Sarah (Master thesis; Mastergradsoppgave, 2023-05-15)
      Atmospheric carbon dioxide (CO2) levels and global temperatures have increased steadily over the past 100 years (IPCC, 2018). Greenhouse gases, such as CO2, and their emissions from soils play an important role in shaping future climate scenarios. Soil microorganisms are responsible for the turnover of soil organic matter and the release of CO2 to the atmosphere (Hartley et al., 2008), thereby ...
    • Microplastics Accumulation in Recirculating Aquaculture Systems (RAS) 

      Eidsvik, Erlend Vartdal (Master thesis; Mastergradsoppgave, 2023-05-14)
      It has in recent years been a shift in the land-based aquaculture production from flow through systems (FTS) to recirculating aquaculture systems (RAS). With emerging use of RAS, it is necessary with knowledge regarding potential issues, whereas one potentially increasing problem is accumulation of microplastics (MP) in the RAS water. The objects of this study were to determine MPs concentration in ...
    • Migration and habitat use of sea trout post-smolts Salmo trutta in a Norwegian fjord system 

      Flaten, Anne Cathrine (Master thesis; Mastergradsoppgave, 2015-05-20)
      The migration and habitat use of sea trout post-smolts were investigated in a fjord system in Central Norway during the period from 30 April – 26 November 2014. The main aims were to investigate timing of sea entry and freshwater return, return rate, marine residence time, spatial use of the fjord system and migration distance. Fifty sea trout smolts were tagged with acoustic transmitters and tracked ...
    • Mitogenomic characterization and phylogenetic position of the oldest living vertebrate species - the Greenland shark (Somniosus microcephalus) 

      Santaquiteria Gil, Aintzane (Master thesis; Mastergradsoppgave, 2016-07-10)
      The Greenland shark (Squaliformes, Somniosus microcephalus) is the largest fish living in Arctic waters, but little is known about its biology. This species lives for at least 272 years and is listed as a near threatened species on the IUCN´s Red list of Threatened Species. As S. microcephalus is the oldest living vertebrate species, it is important to strive for its conservation. The aim of the ...
    • Molecular biology and physiology of isolated chloroplasts from the algae Vaucheria 

      Didriksen, Alena (Master thesis; Mastergradsoppgave, 2010-01)
      Sea slugs of the genus Elysia (e.g. E. chlorotica) are known for their ability to incorporate chloroplasts from the yellow-green alga Vaucheria litorea. These “kleptoplasts” stay active in the digestive tract of the sea slug for several months. Chloroplasts from Vaucheria litorea are also reported to be significantly more stable after in vitro isolation than chloroplasts of other algae or of higher ...
    • Molecular study of digenean diversity in aquatic organisms in northern Norway, with a focus on the seasonality of Crepidostomum [Braun, 1900] 

      Slåteng, Sigurd (Master thesis; Mastergradsoppgave, 2022-06-07)
      This study aimed to elucidate cryptic trematode diversity across multiple life stages in aquatic organisms. I collected samples from first intermediate hosts (bivalves), second intermediate hosts (amphipods and insect nymphs), and definitive hosts (fish), and identified them by use of molecular methods. Phylograms based on molecular markers from 28S and COI genes were used to identify nine species ...
    • Monitoring anthropogenic activity in the Hardangervidda wild reindeer range. Possible applications of crowdsourced Strava-data in remote settings 

      Holtmoen, Vilde Grøthe (Master thesis; Mastergradsoppgave, 2021-05-31)
      Seen in light of the increasing interest of nature-based tourism and recreational outdoor activities in Norway the last decades (Haukeland, Grue & Veisten, 2010), spatiotemporal information on human activity in remote areas and knowledge about how this activity may affect wildlife and nature is a crucial part of a knowledge-based management (Gundersen et.al., 2011, p.14; Gundersen, Strand & Punsvik, ...
    • Morphological divergence in a trimorphic population of Arctic charr (Salvelinus alpinus (L.)) in Skogsfjordvatn, northern Norway. 

      Skoglund, Sigrid Østrem (Master thesis; Mastergradsoppgave, 2013-09-30)
      Sympatric polymorphisms are found in many freshwater fish taxa, including the salmonid Arctic charr (Salvelinus alpinus (L.)). Polymorphism is often expressed as differences in morphology, behaviour and life-history strategies, and may be driven by alternative phenotypic adaptations to resource use such as habitat and prey preferences. Morphological divergence is usually linked to different functions ...
    • Morphological variation in the redfish (Sebastes spp.) complex in Norwegian waters 

      Bruvold, Ingrid Marie (Master thesis; Mastergradsoppgave, 2021-06-02)
      The golden redfish Sebastes norvegicus is a long-lived commercial species of redfish in the North Atlantic. Excessive harvest through decades has led to a decline in the mature population in Norwegian waters, which is currently considered to be severely depleted. Accumulating genetic evidence suggest a more complex structure within the Sebastes genus in the North Atlantic, which has recently formed ...
    • Movement ecology of the Qamanirjuaq caribou (Rangifer tarandus groenladicus) herd with focus on their wintering grounds 

      Fredlund, Matt (Master thesis; Mastergradsoppgave, 2015-05-15)
      With a rapidly changing climate in the arctic there is concern that specialized species, such as caribou (Rangifer tarandus), may not be able to adapt. Currently, the importance of climatic changes for North-American caribou herds is unclear. In an effort to reduce this knowledge gap I have analysed the movement behaviour of caribou in the Qamanirjuaq herd, in the central Canadian Arctic, in relation ...
    • Movements and diving behavior of humpback whales in relation to the capelin distribution in the Barents Sea 

      Skalmerud, Stine (Master thesis; Mastergradsoppgave, 2022-05-16)
      Humpback whales (Megaptera novaeangliae) are a cosmopolitan species, migrating between their mid- and high latitude foraging- and low latitude breeding grounds. Of these, the Northeast Atlantic (NEA-) population cover the longest migration distance of all mammals that last up to half a year. On the foraging grounds they feed extensively throughout the summer until early winter to gain enough energy ...
    • Neighbourhood watch among common eiders (Somateria mollissima) – Does group nesting reduce nest predation? 

      Hennig, Gaute Widerøe (Master thesis; Mastergradsoppgave, 2022-05-16)
      Colony nesting is thought to be an example of the selfish herd strategy, where aggregating behaviour may be an evolutionary adaptation to reduce the risk of predation. The common eider (Somateria mollissima) is a ground nesting sea bird susceptible to high nest predation rates through the nesting period. They often nest in groups, yet some also choose to nest solitarily. I examined whether group ...
    • Nest site selection by northern goshawk Accipiter gentilis in northern coastal birch forests 

      Andersen, Ellen F. (Master thesis; Mastergradsoppgave, 2008-06-03)
      Most studies of nest site selection by northern goshawk, Accipiter gentilis, have been done in mixed – or coniferous forests, and emphasis has been put on the importance of large trees and relatively intact, old forest stands for nesting sites. However, goshawks in northern Norway are found in birch forests characterized by relatively small trees and a high natural level of fragmentation. In this ...
    • The nestling diet of Svalbard snow buntings identified by DNA metabarcoding 

      Stolz, Christian (Master thesis; Mastergradsoppgave, 2019-05-15)
      Tundra arthropods have considerable ecological importance as a food source for several bird species that are reproducing in the Arctic. The actual arthropod taxa comprising the chick diet are however rarely known, complicating assessments of ecological interactions. In this study, I identified the nestling diet of Svalbard snow bunting (Plectrophenax nivalis) for the first time. Faecal samples of ...
    • A new look at whale behavior: identifying multiple spatial movement patterns of Norwegian killer whales 

      Van Ruiten, Meghan (Master thesis; Mastergradsoppgave, 2021-05-25)
      Studying an animal’s movement patterns in both space and time can shed light on the strategies individuals use to optimize foraging and adapt to seasonal and environmental variation. Killer whales (Orcinus orca) are dynamic, apex predators inhabiting all the world’s oceans, predating and specializing on a wide variety of prey. Over the last decade, large numbers of Norwegian killer whales have been ...
    • Nitrogen Excretion and Aspects of Water Balance in Fasting Hooded Seal Pups (Cystophora cristata) 

      Coyle, Matthew (Master thesis; Mastergradsoppgave, 2022-06-10)
      The post-weaning fast of hooded seal pups (Cystophora cristata) is not well understood. What energy sources are being used? How is water balance maintained? How are these mechanisms balanced with thermoregulation? This study aims to answer some questions on the physiological mechanisms in place to assist an Arctic seal pup in the early stages of their life with no source of food or freshwater. ...
    • No evidence of optimal foraging in chick-raising black-legged kittiwakes (Rissa tridactyla) in the Southern Barents Sea 

      Thorvaldsen, Renate (Master thesis; Mastergradsoppgave, 2013-05-21)
      The black-legged kittiwake (Rissa Tridactyla) situation is getting more serious as the population numbers have declined over the last decades, and this well-known species is now considered endangered (EN) in the Norwegian redlist 2010. This study investigates the differences between adult and chick diet considering prey selection to be an important point. Earlier chick diet has been considered a ...