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norskBlar i tittel Mastergradsoppgaver i biologi
Viser treff 351-362 av 362
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Validating the Tritiated Water Method in Adult Harp Seal
(Master thesis; Mastergradsoppgave, 2022-05-16)As one of the top predators in the northeast Atlantic, and most numerous, the harp seal (Pagophilus groenlandicus), has a significant role in the higher trophic levels in the ecosystem. Their condition can be an indicator of changes in prey availability, competition with other species or even climate. It can also be a useful tool in predicting the pup production and breeding success. The ... -
Variation in abundance, diet, otolith zone patterns and black spot disease (Cryptocotyle lingua) of 0-group coastal cod (Gadus morhua L.) in northern Norway
(Master thesis; Mastergradsoppgave, 2006-12-11)Knowledge of the early life-history and habitat requirements of coastal cod is very sparse. Young of the year cod juveniles from three different locations in northern Norway were collected monthly from August to November 2005 using beach seine. Diet analyses based on stomach contents showed that 0-group cod mainly ate copepods, gammarids, polychaetes, mysids, shrimps and isopods. The three ... -
Variation in egg size, fecundity and size structure in female red king crab (Paralithodes camtschaticus, Tilesius 1815) from Varangerfjorden over time.
(Master thesis; Mastergradsoppgave, 2018-05-14)The introduced red king crab (Paralithodes camtschaticus) has successfully established in Norwegian waters since its release to the Barents Sea in the 1960’s. It has become an important commercial resource contributing to the local coastal society in the eastern region of Finnmark. The fishery consists of one quota regulated area east of 26° (North Cape) and an open fishery west of 26°E. During the ... -
Variation in epiphytic vegetation in spruce plantations and adjacent native birch forests in North Norway
(Master thesis; Mastergradsoppgave, 2007-05)Epiphytic vegetation can contribute to increased knowledge on how planting of spruce in areas where spruce does not occur naturally in the landscape can affect the environment. In the current study, 31 spruce plantations in Troms and Vesterålen in North Norway were investigated, with emphasis on species abundance of macrolichens on tree trunks and branches. The main assumption was that planting of ... -
Vegetation-environment analysis of areas with peat accumulation and hummock formation in the context of NiN (Natur i Norge). A study from Laggu, Gamvik municipality, Troms and Finnmark county.
(Master thesis; Mastergradsoppgave, 2021-05-18)A conspicuous type of heath and forest with peat accumulation and hummock formation in terrestrial systems has been investigated in Laggu, Gamvik municipality in northern Norway. The aim was to describe vegetational composition, soil depth and hummock distribution, and identify environmental factors that cause terrestrial peat accumulation. Vascular plants, bryophytes and lichens were registered ... -
Vertical distributions of zooplankton using the Video Plankton Recorder in two high-latitude fjords. “A case study on diel migration in Billefjorden, Svalbard, and seasonal migration in Porsangerfjord, northern Norway”
(Master thesis; Mastergradsoppgave, 2015-08-17)Zooplankton is the link between primary producers and higher trophic levels, so it is of vital importance for the food chain. The strong seasonality in the Arctic affects the vertical distribution of zooplankton in the water column. Predators can also affect the vertical distributions of their prey in the water column due to avoidance adaptations. The importance of these differences between prey and ... -
Vertikalt habitatbruk, næringsvalg og vekst hos en innsjølevende bestand av ørret (Salmo trutta L.) i Pasvikvassdraget
(Master thesis; Mastergradsoppgave, 2007-10-16)En av våre nordligste fiskespisende ørretbestander finnes i Pasvikvassdraget i Finnmark. Omfattende regulering av vassdraget har virket negativt på bestanden, og den blir nå opprettholdt gjennom årlige utsettinger. På 1990-tallet innvandret lagesild fra Enare-sjøen, og den ser ut til å ha hatt positiv effekt på ørreten. Denne undersøkelsen omhandler habitatbruk, næringsvalg og vekst hos innsjølevende ... -
Winter behaviour of riverine anadromous Arctic charr and sea trout in northern Norway
(Master thesis; Mastergradsoppgave, 2008-05)Based on earlier migration studies of lake-dwelling anadromous Arctic charr Salvelinus alpinus (L.) and sea trout Salmo trutta L. in northern Norway, both species are believed to solely overwinter in fresh water and spend only one to three months in the sea during summer. This is an assumption upon which all current management of the species in the area is based, although no studies have focused on ... -
Within-Season Trends in Abundance and Distribution of Humpback Whales (Megaptera novaeangliae) in the Antarctic Peninsula Region
(Master thesis; Mastergradsoppgave, 2020-12-15)Fine-scale knowledge of cetacean abundance and distribution throughout the Antarctic Peninsula (AP) is lacking yet essential for effective ecosystem-based fisheries management (EBFM). We investigated an important area both for migratory humpback whales (Megaptera novaeangliae) and Antarctic krill (Euphausia superba) fisheries to assess potential spatio-temporal interactions, for use in adaptive EBFM ... -
The world's northern most harbour seal population - How many are there?
(Master thesis; Mastergradsoppgave, 2012-11-15)This study presents the first abundance estimate for the world's northernmost harbour seal (Phoca vitulina) population, which resides in Svalbard, Norway, based on three digital stereoscopic photographic surveys conducted in 2009 and 2010. The counts from these high resolution 3D images were combined with a novel method for estimating correction factors for animals that were in the water at the time ... -
Yearly variation in allelopathic compound production along a climatic gradient. A case of study of Empetrum nigrum
(Master thesis; Mastergradsoppgave, 2017-11-15)Empetrum nigrum is a plant common in northern ecosystems with capacity to produce allelopathic compounds, which among other effects inhibit seed establishment and germination of other plants. Some of the most studied compounds regarding this effect are batatasin-III and phenolic acids, among them caffeic acid, which account for a large proportion of the leaf’s biomass. 5 random sites were established ... -
Zooplankton communities on the Northeast coast of Greenland. How can we explain vertical and regional distribution?
(Master thesis; Mastergradsoppgave, 2019-05-16)Most studies on zooplankton investigate the famous, and omnipresent, Calanoid copepods Calanus spp., because they are abundant, and constitute the major trophic link in marine ecosystems. Indeed, Northeast Greenland is located on the crossroad of Arctic and Atlantic waters which, potentially, can lead to a high biodiversity originating from different domains of marine life. However, there are very ...
