Mastergradsoppgaver i biologi: Nye registreringer

Viser treff 301-320 av 380

    • Fine scale haul-out behaviour of harbour seals (Phoca vitulina) at different localities in northern Norway 

      Herstrøm, Kristin (Master thesis; Mastergradsoppgave, 2013-05-14)
      The haul-out behaviour of harbour seal (Phoca vitulina vitulina) is influenced by several factors such as the tidal state and environmental variables. Understanding these effects is important for designing counting-surveys providing data necessary to be able to estimate population size. The haul-out behaviour of harbour seals was investigated during the moulting period in three different localities ...

    • Do mothers manipulate grandparental care? 

      Bruksås, Ina Jeanette (Master thesis; Mastergradsoppgave, 2013-05-15)
      Many studies have been done on grandparental investment, asking why grandparents distribute their resources skewered. Maternal grandmothers invest most, and parental grandfathers invest least in their grandchildren. Here resemblance is used as an indicator of kin, asking if grandparents feel their grandchildren resemble them and looking at how they invest in these grandchildren. Daughters do not ...

    • Temporal and spatial variation in a high Arctic bedrock macrobenthic community in Hinlopen, Svalbard. A baseline study related to possible climatic change 

      Ballantine, Carl (Master thesis; Mastergradsoppgave, 2013-08-15)
      Zonation patterns within a high Arctic, hard bottom community within the Hinlopen Strait, Svalbard were investigated using image analysis of underwater photoquadrates. This long term study consists of depth transects taken over a six year period were on a sublittoral vertical wall permanent monitoring station. Analysis indicated that the depth in which the greatest number of species occurred increased ...

    • Terrestrial locomotion in the Svalbard ptarmigan (Lagopus muta hyperborea). How does treadmill running compare with running overground? 

      Vik, Anne Marit (Master thesis; Mastergradsoppgave, 2013-05-16)
      The Svalbard rock ptarmigan (Lagopus muta hyperborea) is a resident bird on the Svalbard achipelago, living in an environment where it experiences extreme climatic and photoperiodic conditions. The bird’s most striking adaption to this environment is, prior to the onset of winter, its deposition of fat, comprising up to 30% of body mass. Moving around with this excess mass may prove difficult as it ...

    • Life history strategies of a trimorphic population of Arctic charr (Salvelinus alpinus (L.)) in Skogsfjordvatn, northern-Norway 

      Smalås, Aslak (Master thesis; Mastergradsoppgave, 2013-05-15)
      Polymorphisms are widespread throughout many different taxa of vertebrates. Discrete polymorphisms or morphs usually differentiate in morphology, ecology and life history, most likely driven by adaptations to different habitats and resources. For sympatric morphs to be able to maximize fitness in different niches and habitats, they may develop differences in several life history traits. Arctic charr ...

    • 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 ...

    • Threat or opportunity? Landscape genetics in a coal mining area 

      Skottvoll, Bente Sved (Master thesis; Mastergradsoppgave, 2013-05-15)
      Aknowledgment The area of Sveagruva have experienced several periods of coal mining. This study aim to evaluating changes in vegetation composition, species distributions and genetic structure using a combination of field and molecular analyses, to identify whether or not coal mining have effected plant life in Svea. Investigations on species and gene level were done on two Luzula species, L. ...

    • The quick and the slow: Competitive ability of two silica-rich grasses influenced by large and small herbivores 

      Lægreid, Eiliv Jenssen (Master thesis; Mastergradsoppgave, 2013-05)
      Silicate-rich grasses often dominate in heavily grazed areas, presumably because high amounts of silica deter herbivores. Activity of large herbivores and small rodent herbivores increase competitive ability of silicate-rich grasses, possibly through apparent competition. Both types of herbivores often co-exist in grassland ecosystems. Their potential additive effect on competitive ability of ...

    • Adaptive radiation of the European whitefish Coregonus lavaretus (L.) in the Pasvik watercourse: the genetic description of a new morph 

      Couton, Marjorie (Master thesis; Mastergradsoppgave, 2012-11-26)
      Sympatric occurring fish morphs in postglacial lakes usually exhibit differences in morphology and physiology driven by adaptations to differential trophic niches. The European whitefish (Coregonus lavaretus (L.)) is a highly variable fish species, with more than 200 intraspecific forms described in Europe. The morphs usually differ in their number of gill-rakers, therefore this trait has been ...

    • Populasjonsstruktur, kjønnsmodning og variasjon i fekunditet hos kongekrabbe (Paralithodes camtschaticus) i Porsangerfjorden, Finnmark : et litteratur- og feltbasert studium 

      Lindberg, Ken Ståle J. (Master thesis; Mastergradsoppgave, 2012-11-22)
      Russiske forskere introduserte kongekrabben, Paralithodes camtschaticus, til Barentshavet på 1960 og 1970-tallet for å gi lokale fiskere en ny art å høste av. Det var antatt at spredning til norske farvann var lite sannsynlig. Artens etablering ble en suksess sett fra russisk side. Kongekrabben har nå spredt seg over hele kysten av Finnmark fylke, og Porsangerfjorden er den siste av fjordene ...

    • Seawater consumption in dehydrated hooded seals (Cystophora cristata) 

      Verlo, Are (Master thesis; Mastergradsoppgave, 2012-03)
      Studies based on satellite-tracking show that hooded seals (Cystophora cristata) spend many months out in the open sea each year. When the seals are out in the open sea they have no access to fresh water. Experimental studies have showed that hooded seals drink seawater and that they have the capacity to produce urine with Na+ and cl- concentrations equal to or higher than that of seawater. They ...

    • Population dynamics, diet and trophic positioning of three small demersal fish species within Porsangerfjord, Norway 

      Källgren, Emma Katarina (Master thesis; Mastergradsoppgave, 2012-11-15)
      In today’s society, one often stumbles over the quote “you are what you eat”. Diet is closely related to fish size and physical conditions, so in order to understand the food web one must first understand the population dynamics of the fish. Three demersal species in the northern hemisphere are; Artediellus atlanticus, Myoxocephalus scorpius and Leptagonus decagonus. The study was undertaken in ...

    • Effects of various early life history temperature regimes on development and metamorphosis of Atlantic cod (Gadus morhua) larvae 

      Bashan, Tolga (Master thesis; Mastergradsoppgave, 2012-12-13)
      The growth and important structures development in different temperature regime histories were studied during mid-metamorphosis stage of Atlantic cod (Gadus morhua) larvae. In order to see the growth and the organ development differentiation due to different temperatures at a given stage, we exposed the larvae into 4 different temperature regimes; L-L (low temperature at incubation, low temperature ...

    • The dually targeted transcription factor TF1 and its role in the expression of plastid- and nuclear-encoded photosynthesis genes 

      Olsen, Stian (Master thesis; Mastergradsoppgave, 2012-09-05)
      In plant cells, the distribution of genes on three spatially separated subgenomes calls for the necessity of maintaining a coordinated regulation of gene expression between these DNA-containing compartments. Especially, the translocation of nuclear-encoded gene products to plastids and mitochondria, which is crucial for the development and metabolic operation of these semi-autonomous organelles, ...

    • Effect of Dileka treatment on bacteria in a circulating system 

      Ludvigsen, Tommy (Master thesis; Mastergradsoppgave, 2012-12-03)
      The aim of the study was to investigate if the Dileka-cell reduces bacterial survival in municipal drinking water in Tromsø, and if such an effect was found, also to discuss possible mechanisms involved in such an anti-bacterial effect. A pilot study was conducted first, followed by a series of 8 experiments (4 with Dileka and 4 without Dileka (control)). Since no documentation of active mechanisms ...

    • The effect of trapping on Arctic Foxes in Svalbard : demography and genetics 

      Meldrum, Elaine Alice (Master thesis; Mastergradsoppgave, 2012-12-07)
      For hundreds of years arctic foxes on the Svalbard archipelago have been hunted and trapped for their warm and attractive fur. However, little is known about the effect that trapping has on this species population structure. Here I assess the effect of trapping on arctic foxes by comparing the demographic and genetic structure of foxes from the Austfjordnes area in Svalbard over three consecutive ...

    • 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 ...

    • Do saproxylic beetles respond numerically to rapid changes in dead wood availability following moth outbreaks? 

      Schultze, Sabrina (Master thesis; Mastergradsoppgave, 2012-05)
      Outbreaks of defoliating insects periodically cause mass mortality of trees, thereby generating pulses of dead wood resources for saproxylic (i.e. dead-wood dependent) organisms. This study investigated the responses of saproxylic beetles to a dead wood resource pulse caused by recent (2001-2009) outbreaks of geometrid moths in the subarctic mountain birch forest of the Varanger region in northern ...

    • Repeatability of daily energy expenditure in kittiwakes Rissa tridactyla 

      Lassen, Charlotte Alexander (Master thesis; Mastergradsoppgave, 2012-05-15)
      Estimates of repeatability (R) are an important statistic tool in assessing the consistency of individual differences and thus different phenotypes. A high repeatability of estimates of the daily energy expenditure (DEE), allow for better inferences of the long term energetic effort of individuals, as well as for sound correlations of other traits related to individual performance, such as reproductive ...

    • Demographic patterns in winter carcass use by Golden Eagle and White-tailed Eagle in Finnmark, Norway 

      Pálsdóttir, Elínborg Sædís (Master thesis; Mastergradsoppgave, 2012-02)
      The carcass use of juveniles, subadults and adults of the two eagle species in Norway, the White-tailed Eagle (Haliaeetus albicilla) and the Golden Eagle (Aquila chrysaetos) was studied in Finnmark, the northernmost county of Norway for two winters, in 2009 and 2010. Artificial carrion was laid out as bait on four peninsulas, along with automatic digital cameras which took picture on 5-15 minutes ...