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norskMastergradsoppgaver i biologi: Nye registreringer
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Sesongvariasjoner i aktivitet og dybdebruk hos kystnær atlanterhavskveite (Hippoglossus hippoglossus)
(Master thesis; Mastergradsoppgave, 2015-05-21)Atlanterhavskveite er en ettertraktet fisk både for sportsfiskere og kommersielt fiske på grunn av størrelse og verdi. Bestanden regnes som høy i Nord-Norge, men lav i Sør-Norge. Det fiskes betydelige kvanta av arten i nordlige deler av landet, til tross for at kunnskap om atferd og livshistorietrekk er mangelfull. Hovedmålet med denne oppgaven var derfor å undersøke dybde- og temperaturbruk, og ... -
Behaviour and saltwater tolerance of European whitefish Coregonus lavaretus (L.) in an Arctic estuary
(Master thesis; Mastergradsoppgave, 2015-05-27)Abstract European whitefish is well described and renowned for its polymorphism and faculty to occupy a wide range of freshwater habitats. This includes observations of individuals in some populations that utilize brackish estuarine habitats as feeding areas, although information on these populations is generally scarce. By use of acoustic tracking technology and physiological sampling, the ... -
Migration and habitat use of sea trout post-smolts Salmo trutta in a Norwegian fjord system
(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 ... -
The utility of in vitro Precision-Cut Liver Slices to investigate toxicity pathways of contaminants in polar cod (Boreogadus saida)
(Master thesis; Mastergradsoppgave, 2015-06-12)The development of in vitro methodologies has contributed significantly in elucidating mechanisms of xenobiotic toxicity in aquatic organisms. The present study aimed to develop the in vitro methodology Precision-Cut Liver Slices (PCLS) and to investigate the effects of model compounds (WY-14,643 [WY] and benzo(a)pyrene [BaP]) and two mixtures of 2- and 3-4-ring polycyclic aromatic hydrocarbons ... -
Breeding success in relation to telomere length in a long-lived seabird, the Antarctic Petrel (Thalassoica antarctica)
(Master thesis; Mastergradsoppgave, 2015-05-15)Integrating information about the physiology of individuals and their reproductive performance can be a key aspect in determining the relationships between environmental conditions and demographic parameters, and of the individual variability in these relationships. Telomeres are the protective caps of chromosomes found in eukaryotic cells. They generally shorten in relation to the stressors an ... -
Depth use of adult Atlantic salmon during the first and last phase of the marine migration
(Master thesis; Mastergradsoppgave, 2015-05-15)The Atlantic salmon has declined in numbers over the last decades. Given the species’ anadromous nature, management is a challenge, and information is lacking, especially from the marine migratory phase. Information about repeat spawners and their migratory behaviour may be of major importance in management questions, as these individuals have been found to contribute significantly to spawning ... -
Sesongmessig vandringsmønster til sjørøye og sjøørret i to nordnorske elver - en sammenligning mellom to arter i to elver
(Master thesis; Mastergradsoppgave, 2014-11-20)Sjørøye og sjøørret er anadrome fisker som vandrer mellom ferskvann og sjøvann. Det meste av kunnskapen om vandringsadferden på disse fiskene er gjort på bestander som har tilgang til innsjøer i ferskvannssystemet, i tillegg til at studiene ofte er relativt kortvarige undersøkelser som ikke strekker seg over et helt år. Kunnskapen om anadrome elvelevende bestander er til forskjell mangelfull, spesielt ... -
Studie av bunnforhold og forekomst og tetthet av utvalgte fisk og pigghuder - Evaluering av undervannsfilming som metode
(Master thesis; Mastergradsoppgave, 2015-02-15)Undervannsvideo er en metode for beregning av forekomst av marine dyr og kartlegging av bunnsubstrat og algedekke. Metoden har vært sammenlignet med andre metoder som dykking og bunntrål (Spencer et al. 2005). I dette studiet ble det gjort en evaluering av undervannsfilm som metode for undersøkelse av forekomst og tetthet av utvalgte fisk og pigghuder, og kartlegging av bunnforhold på grunt vann. ... -
Lipid content, composition and dynamics in northern marine diatoms. An experimental study using different analytical methods
(Master thesis; Mastergradsoppgave, 2014-11-20)In this study, the fluorophore Nile Red was used as a probe for lipid accumulation during nutrient stress in the diatom Coscinodiscus concinnus, and to quantify lipid concentration fluorometrically in 5 monocultures of northern diatoms. The results from the fluorometrical quantification were validated by solvent extraction and HPLC-MS analysis in Bergen. In addition, 17 monocultures of 7 species of ... -
Annual population dynamics of the small harpacticoid copepod Microsetella norvegica in a high latitude fjord (Balsfjord, Northern Norway)
(Master thesis; Mastergradsoppgave, 2014-11-16)Annual population dynamics and vertical distribution of the small (< 0.6 mm) hapacticoid copepod, Microsetella norvegica, was investigated through monthly sampling at station Svartnes in Balsfjord, Northern Norway from May 2013 to June 2014. M. norvegica is a pelagic particle feeder, and distributed from temperate waters to sub-arctic fjords, but frequently underestimated because of its small size. ... -
Space use by South Polar Skua during the breeding season at Svarthammaren, Antarctica
(Master thesis; Mastergradsoppgave, 2014-11-17)South Polar Skua is a seabird feeding on both marine resources and on other seabirds’ egg and chicks. There are few studies investigating South Polar Skua space use during breeding season and how it is affected by sex or phenology. This study was carried out during the breeding season 2012-2013 at Svarthammaren in Dronning Maud Land (71° 53′ S, 05° 10′ E). 56 GPS loggers were used to track 48 ... -
The summer diet of hooded (Cystophora cristata) and harp (Pagophilus groenlandicus) seals in the West Ice
(Master thesis; Mastergradsoppgave, 2014-08-15)The harp (Pagophilus groenlandicus) and hooded (Cystophora cristata) seals both inhabit the drift ice areas in the West Ice during certain times of the year, and the present study is part of the Institute of Marine Research’s management studies of these seals. Contents of gastrointestinal tracts from hooded and harp seals from June-July 2008 and 2010 and harp seal faeces samples were identified ... -
"Can energy expenditure of free-ranging kittiwakes be estimated by body acceleration?"
(Master thesis; Mastergradsoppgave, 2014-08-15)Abstract The way energy is used and acquired are fundamental questions in animal biology and figure greatly into conservation of a species. Accurate estimates of energy expenditure are critical in understanding how successful animals are throughout their lifespan and in quantifying population energy budgets and their role and impact on an ecosystem. Two methods have been commonly used to estimate ... -
Efflux of neurotransmitter from brain slices during O2 deprivation – comparing diving and non-diving species
(Master thesis; Mastergradsoppgave, 2014-08-15)During hypoxic insult, neuronal tissue undergoes an excitotoxic cascade of events leading to cell death. This response involves loss of membrane potential and uncontrolled release of primarily excitatory neurotransmitters. I propose that this fatal cascade is significantly delayed or attenuated in diving species, which are adapted to repeated exposures to hypoxic conditions as a consequence of ... -
Organohalogenated contaminants in nestlings of white-tailed eagles (Haliaeetus albicilla): Plasma concentrations and possible influences on biomarkers of health
(Master thesis; Mastergradsoppgave, 2014-09-15)Biomagnifying organohalogenated contaminants (OCHs) may have adverse effects on the health of birds, especially in marine avian top predators that accumulates high loads of such contaminants. Contaminants may impact the immune system by impairment of the humoral immunity and also influence the antioxidant enzyme activity. Moreover, developmental conditions may affect the shortening of telomeres, one ... -
Spectral Analysis and image classification of the dwarf shrub Empetrum nigrum (L.) by means of remote sensing data.
(Master thesis; Mastergradsoppgave, 2014-05-15)Empetrum nigrum dominates in alpine and northern part of Norway. It is an allelopathic species that can reduce both productivity and biodiversity in ecosystems. The study focuses on identifying and determining different cover of E. nigrum by means of remote sensing data within two regions of Northern Norway, Ifjord in Finnmark and Troms areas. Field data were collected within 50 study points and E. ... -
Ungulate population monitoring in a tundra landscape: evaluating total counts and distance sampling accuracy
(Master thesis; Mastergradsoppgave, 2014-05-19)Researchers and managers are constantly working towards decreasing monitoring uncertainties in order to improve inferences in population ecology. The solitary and sedentary Svalbard reindeer (Rangifer tarandus platyrhynchus) inhabit a high-Arctic tundra landscape highly suitable to compare accuracy (precision and bias) of population monitoring methods in the wild. The flexible Bayesian state-space ... -
Can ground nesting birds escape predation by breeding in less productive habitats? A large-scale artificial nest study from Finnmark, Northern Norway
(Master thesis; Mastergradsoppgave, 2014-05)Predation is known to be one of the most important causes of nest failure in ground nesting birds, and many populations are experiencing a decline in breeding success worldwide. Predator abundance are expected to be highest closer to productive areas (i.e. Ecosystem exploitation hypothesis), and vary according to the availability of other prey (i.e. Alternative prey hypothesis). I hypothesized that ... -
Sampling site and potential errors in estimating total body water and water turnover rate in fasting hooded seals (Cystophora cristata)
(Master thesis; Mastergradsoppgave, 2014-05-15)The purpose of this project is to study in detail the water balance and methodological aspects of the use of the tritiated water method of hooded seals (Cystophora cristata). Following 24 hours of fasting, 5 sub-adult hooded seals aged 1.5 years were injected intravenously with a bolus dose of tritiated water through a catheter inserted into the extradural intravertebral vein (EDV) at the level of ... -
Parallelism in parasite infections in two populations of polymorphic Arctic charr (Salvelinus alpinus L.) in northern Norway
(Master thesis; Mastergradsoppgave, 2014-05-15)The composition and structure of a component community can vary widely across host populations of the same host species. Revealing the causes and consequences of geographical variation in parasite community composition is of great importance in order to determine parasites role in an ecosystem. Divergence in parasite infections among sympatric polymorphic Arctic charr is commonly associated with ...
