Browsing Økologi by Title
Now showing items 1-20 of 40
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(Master thesis / Masteroppgave, 2008)Many fish stocks today are declining due to the heavy harvesting and the increasingly demand for more food caused by the growing human population. Life-history trait as age and size at maturity are affected, the fish are ...
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(Master thesis / Masteroppgave, 2008)The coastal cod is an important commercial and recreational resource for the local communities in the Skagerrak. The situation of this and neighbouring stocks has worsened for decades, promoting an imperative need for ...
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(Master thesis / Masteroppgave, 2010)A total of 20 water traps were set out at four locations around Longyearbyen on the High Arctic island Spitsbergen. The traps sampled aerially dispersed invertebrates during the summer of 2008. These trapping locations ...
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(Master thesis / Masteroppgave, 2009)The northern blue whiting is a small mesopelagic gadoid, widely distributed in the north‐east Atlantic. The fishery on this species is extensive and is of commercial importance for several states, also Norway. There have ...
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(Master thesis / Masteroppgave, 2006)Abstract A lot of studies have been performed on demographic changes in ungulate population due to density dependence, but little is done on density dependent changes in foraging behaviour which can be a mechanism of such ...
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(Master thesis / Masteroppgave, 2008)Summary The anti-predatory behaviour displayed by female Great Tit (Parus major) and Blue Tit (Cyanistes caereleus) in the nestbox was studied to observe possible differences in response between the species, and also ...
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(Master thesis / Masteroppgave, 2010)Fuglesang blir generelt betraktet som et seksuelt selektert trekk, og hos mange sangfuglarter er hunner vist å foretrekke hanner med høy sangytelse eller kompleks sangstruktur. Utviklingsstresshypotesen foreslår at lærte ...
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(Master thesis / Masteroppgave, 2010)Fuglesang er gjentatte ganger blitt vist å være et seksuelt selektert trekk som kan reflektere aspekter av hannlig kvalitet. Lærte sangtrekk, som for eksempel repertoarstørrelse, er foreslått å ha kostnader knyttet til ...
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(Master thesis / Masteroppgave, 2008)The nutritional stress hypothesis formulated by Nowicki et al. (1998) is based on the findings that brain structures underlying song learning in songbirds largely develop during the first few months post-hatching; a period ...
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(Master thesis / Masteroppgave, 2009)In many species of birds, the quality of the nest site may have important fitness consequences. The focus of the present study was to see if nest box choice in blue tits (Cyanistes caeruleus) and great tits (Parus major) ...
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(Master thesis / Hovedoppgave, 2004)To understand the ecological effects of large herbivores, it is important to understand foraging behaviour and how this is affected by density. In this experiment, domestic sheep (Ovis aries) were kept at high (80 sheep ...
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(Master thesis / Masteroppgave, 2006)Abstract In the recent decades large carnivores have started to recolonize former occupied areas in North America and in Europe. Increases in predator population sizes can affect the whole ecosystem functioning, but little ...
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(Master thesis / Masteroppgave, 2008)
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(Master thesis / Masteroppgave, 2011)Phleum pratense (timotei) dyrkes kommersielt som fôr til husdyr. Soppendofytter er vanlig i alle planter, der de har ulike egenskaper som kan påvirke verten samt herbivorer, for eksempel med toksiner. Kunnskapshull i forhold ...
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(Master thesis / Masteroppgave, 2008)Separate gytedemer av harr har etablert seg over 20-25 generasjoner i Lesjaskogsvatn, Oppland fylke. Gytebekkene har konsistent ulike temperaturregimer. Nylige undersøkelser indikerer motgradient veksttilpasning i tidlige ...
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(Master thesis / Masteroppgave, 2008)An upper Ordovician (upper Sandbian) benthic Paleozoic fauna at Langesund in the Oslo graben area has been reviewed. The study area consisted of the uppermost 13 meters of sediments in the Fossum Formation. A species/plot ...
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(Master thesis / Masteroppgave, 2010)Aposematism is a defence system used by toxic animals where the animals use warning colouration, often combined with warning gestures, to fend off predators. The most probable scenario is that the toxicity was developed ...
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(Master thesis / Masteroppgave, 2006)Abstract The heterospecific attraction hypothesis suggests that migrants cue on residents with similar ecological needs to find suitable breeding sites, and that they have reproductive fitness benefits from doing so. In ...
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(Master thesis / Masteroppgave, 2007)Great tit nestlings won’t thrive in nests of the pied flycatcher, even though the opposite has been proven successful. In order to explore some of the reasons why, we performed cross fostering experiments where great tit ...
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(Master thesis / Masteroppgave, 2008)Many freshwater fishes are fragmented into local populations. Brown trout (Salmo trutta) is a fish that express high genetic heterogeneity and are known to be structured into genetically differentiated subpopulations ...