Browsing Institutt for biologi by Title
Now showing items 504-523 of 2519
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Demographic changes in female-skewed populations of house sparrow (Passer domesticus) – An experimental study
(Master thesis, 2023)In nature, an unequal sex-ratio in wild populations is a common occurrence. Many factors could result in skewed sex-ratios, for instance, selective hunting, sex-specific mortality, sex-biased dispersal, etc. A biased ... -
Demographic consequences of harvesting: a case study from a small and isolated moose population
(Peer reviewed; Journal article, 2021)ABSTRACT: Harvesting can have a substantial impact on population dynamics and individual performance in wild populations. While the direct consequences of harvest on individual survival and population growth rate are often ... -
Demographic consequences of rapid climate change and density dependence in migratory Arctic geese
(Doctoral theses at NTNU;2020:156, Doctoral thesis, 2020)Climate change effects are being felt across ecological levels and most strongly in the Arctic. Scaling up from effects on demographic rates to the population-level, and even community-level, is a daunting task. This is ... -
Demographic determinants of population growth rate in willow ptarmigan (Lagopus lagopus) in Lierne, central Norway
(Master thesis, 2018)Willow ptarmigan (Lagopus lagopus) populations in Norway have declined during the last decade and the species was included in the Norwegian Red list in 2015 as near threatened . Accordingly, it is important to identify ... -
Demographic influences of translocated individuals on a resident population of house sparrows
(Journal article; Peer reviewed, 2017)Translocation of individuals from source populations to augment small populations facing risk of extinction is an important conservation tool. Here we examine sex-specific differences between resident and translocated house ... -
Demographic measures of an individual's "pace of life": fecundity rate, lifespan, generation time, or a composite variable?
(Journal article; Peer reviewed, 2018)Comparative analyses have demonstrated the existence of a ^pace-of-life^ (POL) continuum of life-history strategies, from fastreproducing short-lived species to slow-reproducing long-lived species. This idea has been ... -
Demographic routes to variability and regulation in bird populations
(Journal article; Peer reviewed, 2016)There is large interspecific variation in the magnitude of population fluctuations, even among closely related species. The factors generating this variation are not well understood, primarily because of the challenges ... -
Demographic variation, distribution and habitat use between wildebeest sub-populations in the Serengeti National Park, Tanzania
(Doktoravhandlinger ved NTNU, 1503-8181; 2007:191, Doctoral thesis, 2007)This thesis investigates the demographic variation, distribution and wildebeest habitat use in the Serengeti National Park (SNP) and its adjacent protected areas in northern Tanzania. Specifically, the study i) examines ... -
Demographic, Environmental and Evolutionary Aspects of Sexual Selection
(Doktoravhandlinger ved NTNU, 1503-8181; 2012:362, Doctoral thesis, 2012) -
Dendrochronological constructions of Norwegian conifer chronologies providing dating of historical material
(Doctoral thesis, 2002)Tree-ring chronologies have been constructed for Scots pine (Pinus sylvetris L.) in Trøndelag, west Norway and south-east Norway back to AD 765 and AD 871, respectively. These have enabled the absolute dating of floating ... -
Dendroclimatology in southern Norway: tree rings, demography and climate
(Doctoral theses at NTNU;2019:195, Doctoral thesis, 2019)Tree rings provide annually resolved palaeoclimate archives. In southern Norway, time series of tree-ring width and maximum latewood density of Scots pine growing at certain high-elevation locations are correlated to ... -
Dense mesopelagic sound scattering layer and vertical segregation of pelagic organisms at the Arctic-Atlantic gateway during the midnight sun
(Peer reviewed; Journal article, 2021)Changes in vertical and spatial distributions of zooplankton and small pelagic fish impact the biological carbon pump and the distribution of larger piscivorous fish and marine mammal species. However, their distribution ... -
Density effect on growth rate of juvenile Atlantic salmon (Salmo salar) in manipulated large rivers
(Master thesis, 2015)Growth rate of young-of-the-year (YOY) Atlantic salmon (Salmo salar) in low-density rivers was substantial better relative to YOY captured in normal density rivers. Mean growth index ± SD for YOY in low-density rivers was ... -
Density independent use of shallow riverine areas in juvenile Atlantic salmon
(Journal article; Peer reviewed, 2018)Habitat use of aquatic organisms is essential to evaluate effects of many environmental challenges like effects of hydro-power regulation, where stranding may occur under hydropeaking (rapid dewatering of shallow river ... -
Density-dependent selection and the maintenance of colour polymorphism in barn owls
(Peer reviewed; Journal article, 2022)The capacity of natural selection to generate adaptive changes is (according to the fundamental theorem of natural selection) proportional to the additive genetic variance in fitness. In spite of its importance for development ... -
Density‐dependent population dynamics of a high Arctic capital breeder, the barnacle goose
(Journal article; Peer reviewed, 2019)Density regulation of the population growth rate occurs through negative feedbacks on underlying vital rates, in response to increasing population size. Here, we examine in a capital breeder how vital rates of different ... -
Depredation of Livestock by Wild Carnivores and Illegal Utilization of Natural Resources by Humans in the Western Serengeti, Tanzania
(Doktoravhandlinger ved NTNU, 1503-8181; 2007:238, Doctoral thesis, 2007)Human-wildlife interactions play an important role in shaping perceptions and conservation paradigms and the livelihoods in villages neighbouring protected areas. These interactions also determine the future survival of ... -
Depredation of Livestock by Wild Carnivores in the Eastern Serengeti Ecosystem, Tanzania
(Doctoral theses at NTNU;2017:243, Doctoral thesis, 2017)Globally, wild carnivore populations outside protected areas are at threat from retaliatory killings triggered by livestock depredation. Monitoring of livestock depredation in specific areas is essential to formulate ... -
Deregulation of microRNA-155 and its transcription factor NF-kB by polychlorinated biphenyls during viral infection
(Journal article; Peer reviewed, 2018)Polychlorinated biphenyls (PCBs), and similar environmental contaminants, have been linked to virus outbreaks and increased viral induced mortality since the 1970s. Yet the mechanisms behind this increased susceptibility ... -
Describing posterior distributions of variance components: Problems and the use of null distributions to aid interpretation
(Peer reviewed; Journal article, 2023)1. Assessing the biological relevance of variance components estimated using Markov chain Monte Carlo (MCMC)-based mixed-effects models is not straightforward. Variance estimates are constrained to be greater than zero and ...