Blar i Brage NMBU på forfatter "Stien, Audun"
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An integrated population model for a long-lived ungulate: more efficient data use with Bayesian methods
Lee, Aline Magdalena; Bjørkvoll, Eirin Marie; Hansen, Brage Bremset; Albon, Steve D.; Stien, Audun; Sæther, Bernt-Erik; Engen, Steinar; Veiberg, Vebjørn; Loe, Leif Egil; Grøtan, Vidar (Journal article; Peer reviewed, 2015)We develop an integrated population model for Svalbard reindeer Rangifer tarandus platyrhynchus, and demonstrate how this type of model can be used to extract more information from the data and separate different sources ... -
Antler growth as a cost of reproduction in female reindeer
Loe, Leif Egil; Pigeon, Gabriel; Albon, Steve D.; Giske, Pernille Andrine Eriksdatter; Irvine, R. Justin; Ropstad, Erik; Stien, Audun; Veiberg, Vebjørn; Mysterud, Atle (Peer reviewed; Journal article, 2019)The costs of reproduction are important in shaping individual life histories, and hence population dynamics, but the mechanistic pathways of such costs are often unknown. Female reindeer have evolved antlers possibly due ... -
Behavioral buffering of extreme weather events in a high-Arctic herbivore
Loe, Leif Egil; Hansen, Brage Bremset; Stien, Audun; Albon, Steve D.; Bischof, Richard; Carlsson, Anja M.; Irvine, Justin; Meland, Morten; Rivrud, Inger Maren; Ropstad, Erik; Veiberg, Vebjørn; Mysterud, Atle (Journal article; Peer reviewed, 2016)As global warming advances, there is a growing concern about the impact of extreme weather events on ecosystems. In the Arctic, more frequent unseasonal warm spells and rain-on- snow events in winter cause changes in ... -
Congruent responses to weather variability in high arctic herbivores
Stien, Audun; Ims, Rolf Anker; Albon, Steve D.; Fuglei, Eva; Irvine, R.J.; Ropstad, Erik; Halvorsen, Odd; Langvatn, Rolf; Loe, Leif Egil; Veiberg, Vebjørn; Yoccoz, Nigel (Peer reviewed; Journal article, 2012) -
Context-dependent fitness costs of reproduction despite stable body mass costs in an Arctic herbivore
Pigeon, Gabriel; Albon, Steve; Loe, Leif Egil; Bischof, Richard; Bonenfant, Christophe; Forchhammer, Mads; Irvine, Robert Justin; Ropstad, Erik; Veiberg, Vebjørn; Stien, Audun (Peer reviewed; Journal article, 2021) -
Contrasting effects of summer and winter warming onbody mass explain population dynamics in a food-limitedArctic herbivore
Albon, Steve D.; Irvine, R. Justin; Halvorsen, Odd; Langvatn, Rolf; Loe, Leif Egil; Ropstad, Erik; Veiberg, Vebjørn; van der Wal, René; Bjørkvoll, Eirin Marie; Duff, Elizabeth I.; Hansen, Brage Bremset; Lee, Aline Magdalena; Tveraa, Torkild; Stien, Audun (Journal article; Peer reviewed, 2016)The cumulative effects of climate warming on herbivore vital rates and population dynamics are hard to predict, given that the expected effects differ between seasons. In the Arctic, warmer summers enhance plant growth ... -
Demographic buffering of life histories? Implications of the choice of measurement scale
Bjørkvoll, Eirin Marie; Lee, Aline Magdalena; Grøtan, Vidar; Sæther, Bernt-Erik; Stien, Audun; Engen, Steinar; Albon, Steve D.; Loe, Leif Egil; Hansen, Brage Bremset (Journal article; Peer reviewed, 2016)Life-history theory predicts that the vital rates that influence population growth the most should be buffered against environmental fluctuations due to selection for reduced variation. However, it remains unclear whether ... -
Determinants of heart rate in Svalbard reindeer reveal mechanisms of seasonal energy management
Trondrud, Liv Monica; Pigeon, Gabriel; Albon, Steve; Arnold, Walter; Evans, Alina; Irvine, R. Justin; Król, Elżbieta; Ropstad, Erik; Stien, Audun; Veiberg, Vebjørn; Speakman, John R.; Loe, Leif Egil (Peer reviewed; Journal article, 2021) -
Don't go chasing the ghosts of the past: habitat selection and site fidelity during calving in an Arctic ungulate
Paulsen, Ingrid M.; Soininen, Eeva M; Ravolainen, Virve; Loe, Leif Egil; Hansen, Brage Bremset; Irvine, Justin R; Stien, Audun; Ropstad, Erik; Veiberg, Vebjørn; Fuglei, Eva; Pedersen, Åshild Ønvik (Peer reviewed; Journal article, 2021)Arctic, calving, food availability, GPS, Rangifer tarandus platyrhynchus, remote sensing, site fidelity -
Effekter av tap av mor på lammets utvikling på utmarksbeite
Nornes, Regine (Master thesis, 2019)Tap av sau (Ovis aries) på beite til rovdyr har ført til store konflikter mellom sauenæringen og forvaltningen. Det er lite kunnskap rundt mekanismene som fører til tap. Tap av mor tidlig i beitesesongen kan føre til en ... -
Fat storage influences fasting endurance more than body size in an ungulate
Trondrud, Liv Monica; Pigeon, Gabriel; Król, Elżbieta; Albon, Steve; Evans, Alina; Arnold, Walter; Hambly, Catherine; Irvine, R. Justin; Ropstad, Erik; Stien, Audun; Veiberg, Vebjørn; Speakman, John R.; Loe, Leif Egil (Peer reviewed; Journal article, 2021)The fasting endurance hypothesis (FEH) predicts strong selection for large body size in mammals living in environments where food supply is interrupted over prolonged periods of time. The Arctic is a highly seasonal and ... -
Habitat segregation by sympatric juvenile Arctic charr and brown trout in shallow lake areas: a consequence of interspecifc diferences in predator avoidance?
Svenning, Martin; Stien, Audun; Borgstrøm, Reidar (Peer reviewed; Journal article, 2024)In sympatry, juvenile brown trout (Salmo trutta) usually occupy the shallow and most productive areas (littoral zone) of lakes, while juveniles of Arctic charr (Salvelinus alpinus) are found in deeper, less productive ... -
High seasonal overlap in habitat suitability in a nonmigratory High Arctic ungulate
Pedersen, Åshild Ønvik; Soininen, Eeva M; Hansen, Brage Bremset; Le Moullec, Mathilde; Loe, Leif Egil; Paulsen, I.M.G.; Eischeid, Isabell; Karlsen, Stein Rune; Ropstad, Erik; Stien, Audun; Tarroux, Arnaud; Tømmervik, Hans; Ravolainen, Virve (Peer reviewed; Journal article, 2023)Understanding drivers of space use and habitat selection is essential for management and conservation, especially under rapid environmental change. Here, we develop summer and winter habitat suitability models for the ... -
Keeping cool in the warming Arctic: thermoregulatory behaviour by Svalbard reindeer (Rangifer tarandus platyrhynchus)
Williamsen, Linda; Pigeon, Gabriel; Mysterud, Atle; Stien, Audun; Forchhammer, Mads C.; Loe, Leif Egil (Peer reviewed; Journal article, 2019)In animals with long generation times, evolution of physiological and morphological traits may not be fast enough to keep up with rapid climate warming, but thermoregulatory behaviour can possibly serve as an important ... -
Kongeørn (Aquila chrysaetos) og sauehold : variasjon i tap til kongeørn på fylkes- og beiteområdenivå
Rønningen, Mikael Franzén (Master thesis, 2019)I Norge er konfliktene mellom beitenæringa og rovvilt den viktigste årsaken til at størrelsen på rovviltpopulasjonene holdes nede. På midten av 1900-tallet var populasjonene av de norske rovdyrene på sitt laveste, dette ... -
Little impact of over-winter parasitism on a free-ranging ungulate in the high Arctic
Carlsson, Anja M.; Albon, Steve D.; Coulson, Stephen James; Ropstad, Erik; Stien, Audun; Wilson, Kenneth; Loe, Leif Egil; Veiberg, Vebjørn; Irvine, Robert Justin (Journal article; Peer reviewed, 2018)1. Macroparasites have a central place in wildlife ecology because they have the potential to regulate host populations through effects on reproduction and/or survival. However, there remains a paucity of studies that have ... -
Little impact of over-winter parasitism on a free-ranging ungulate in the high Arctic
Carlsson, Anja M.; Albon, Steve D.; Coulson, Stephen J.; Ropstad, Erik; Stien, Audun; Wilson, Kenneth; Loe, Leif Egil; Veiberg, Vebjørn; Irvine, Robert Justin (Journal article; Peer reviewed, 2018)1. Macroparasites have a central place in wildlife ecology because they have the potential to regulate host populations through effects on reproduction and/or survival. However, there remains a paucity of studies that have ... -
Low spatial habitat overlap of herbivores in the High Arctic tundra
Ravolainen, Virve; Paulsen, Ingrid Marie Garfelt; Eischeid, Isabell; Forbey, Jennifer Sorensen; Fuglei, Eva; Hájek, Tomás; Hansen, Brage Bremset; Loe, Leif Egil; Macek, Petr; Madsen, Jesper; Soininen, Eeva M; Speed, James David Mervyn; Stien, Audun; Tømmervik, Hans; Pedersen, Åshild Ønvik (Peer reviewed; Journal article, 2024)Herbivores play a crucial role in shaping tundra ecosystems through their effects on vegetation, nutrient cycling, and soil abiotic factors. Understanding their habitat use, co-occurrence, and overlap is therefore essential ... -
More frequent extreme climate events stabilize reindeer population dynamics
Hansen, Brage Bremset; Gamelon, Marlène; Albon, Steve D.; Lee, Aline Magdalena; Stien, Audun; Irvine, Robert Justin; Sæther, Bernt-Erik; Loe, Leif Egil; Ropstad, Erik; Veiberg, Vebjørn; Grøtan, Vidar (Journal article; Peer reviewed, 2019)Extreme climate events often cause population crashes but are difficult to account for in population-dynamic studies. Especially in long-lived animals, density dependence and demography may induce lagged impacts of ... -
Movement patterns of golden eagles in relation to distribution of reindeer and sheep in Fennoscandia
Nordlie, Ane Dorthea Lundberg (Master thesis, 2022)Predator-livestock conflicts are a big problem worldwide, and usually result in big ethic and economic difficulties. Even though a lot of research has been done on the matter, there are still many uncertainties connected ...