Publikasjoner
NIBIOs ansatte publiserer flere hundre vitenskapelige artikler og forskningsrapporter hvert år. Her finner du referanser og lenker til publikasjoner og andre forsknings- og formidlingsaktiviteter. Samlingen oppdateres løpende med både nytt og historisk materiale. For mer informasjon om NIBIOs publikasjoner, besøk NIBIOs bibliotek.
2018
Sammendrag
Det er ikke registrert sammendrag
Forfattere
Grete H. M. Jørgensen Kari-Ann Dragland Stangen Knut Egil Bøe Inger Hansen Geir Næss Lars Erik RuudSammendrag
Det er ikke registrert sammendrag
Sammendrag
Forskere har flere forslag til tiltak mot rovdyrangrep. Blant annet kan vokterhunder, strømgjerder og å slippe lammene senere på beite, ha god effekt.
Sammendrag
Trodde du at sauebønder slipper dyra sine ut på sommerbeite og bare krysser fingrene for at flest mulig kommer tilbake om høsten? Det høres jo helt uansvarlig ut! Og det ville det også vært. Om det var sant.
Sammendrag
Det er ikke registrert sammendrag
2017
Forfattere
Erling Meisingset Leif Egil Loe Øystein Brekkum Richard Bischof Inger Maren Rivrud Unni Støbet Lande Barbara Zimmermann Vebjørn Veiberg Atle MysterudSammendrag
1. Population-level management is difficult to achieve if wildlife routinely crosses administrative boundaries, as is particularly frequent for migratory populations. However, the degree of mismatch between management units and scales at which ecological processes operate has rarely been quantified. Such insight is vital for delimiting functional population units of partially migratory species common in northern forest ecosystems. 2. We combined an extensive dataset of 412 GPS-marked red deer (Cervus elaphus) across Norway with information on the size and borders of two administrative levels, the governmental level (municipality) and landowner level (local management units, LMUs), to determine the timing and scale of mismatch between animal space use and management units. We analysed how landscape characteristics affected the use of management units and the timing and likelihood of crossing borders between them, in an effort to delineate more appropriate units in various landscapes. 3. Median municipality size could potentially cover 70% of female and 62% of male annual ranges, while only 12% and 4% of LMUs were expansive enough to accommodate migratory routes in females and males, respectively. Red deer migrate along elevational gradients and are more likely to find both suitable lowland winter habitat and higher summer habitat within management units with variable topography. Consistent with this, the likelihood of border crossing decreased with increasing diversity of elevations. 4. Synthesis and applications. We demonstrate a considerable mismatch between animal space use and management units. Far-ranging movements and frequent administrative border crossings during autumn migration coincides with the period of active management (hunting season). Our study also highlights that, due to extensive movements of males, coordination of management aims may provide a more realistic avenue than increasing sizes of local management units. A more general insight is that the degree of mismatch between range use and management units depends on the season and landscape type. This needs to be accounted for when delimitating functional population units of migratory populations.
Sammendrag
Det er ikke registrert sammendrag
Forfattere
Lucie Isabelle Debeffe Inger Maren Rivrud Øystein Brekkum Erling Meisingset Atle MysterudSammendrag
Partial migration is common in a large variety of taxa in seasonally variable environments. Understanding the mechanisms underlying migration is important, as migration affects individual fi tness. Migratory herbivores bene fi t from delayed forage maturation and hence higher food quality during migra- tion and at their summer range, termed the forage maturation hypothesis (FMH). The link between diet quality and rumination time allows migrants eating a higher quality diet to spend less time on rumination, and they can thus allocate more time to additional feeding. However, such an argument implicitly assumes that deer are energy maximizers, while studies have reported also time minimization strategies under risk of predation. Male and female distributions are limited by different factors linked to both body size differ- ences and reproductive strategies, but there is no study investigating differences in activity pattern accord- ing to the individual migratory patterns for male and female deer. We here unify the FMH with the hypotheses predicting sex-speci fi c time allocation strategies. To test predictions of sex-speci fi c activity of resident and migratory red deer ( Cervus elaphus ), we analyzed activity data of 286 individuals that were fi tted with GPS collars from a population in western Norway. While migrants were more active during the migration itself, we found no differences in activity pattern between migrant and resident deer during the main growth season, neither in terms of proportion of daily time active nor in terms of daily mean movement speed, thus rejecting that deer were energy maximizers. Overall, we found that females were more active during the main growth season even after controlling for body size differences. These patterns are consistent with patterns predicted from sexual segregation theory linked to the reproductive strategy hypothesis. Our study highlights how the understanding of migration can be advanced by considering it in the context of different reproductive strategies of males and females.
Forfattere
Ivar Herfindal Unni Støbet Lande Erling Johan Solberg Christer Moe Rolandsen Ole Roer Hilde Karine WamSammendrag
Co-existing species at the same trophic level often segregate with respect to diet, habitat use, or spatial distribution, reducing their direct competition for resources. However, temporal patterns in species-specific habitat use, for instance due to climatic variation, may affect the strength of interspecific interactions, and generate temporal variation in niche partitioning. We assessed temporal variation in habitat overlap between a wild ungulate, moose Alces alces, and two freeranging domestic ungulates, sheep Ovis aries and cattle Bos taurus, on a boreal forest range in southern Norway. We also calculated the distance between species’ realised niches, as well as the width of their realised niches to evaluate the extent of temporal niche partitioning under different diurnal weather conditions. Analyses of each habitat variable suggested complex relationships between species-specific habitat use, photoperiod, and weather, related to species-specific behaviour and activity patterns. We found shorter overall niche distance between moose and sheep, compared to moose and cattle, and shorter niche distances during day and night than during the twilight hours. The niche distance between moose and sheep was positively related to temperature during night, but negatively during day. Moreover, niche distance between moose and both sheep and cattle was negatively related to precipitation at daytime. Moose niche width was narrower in periods with short niche distance to sheep, while we did not find such pattern towards cattle. A lack of similar moose response to cattle could be attributed to lower niche overlap between moose and cattle. Our results suggest that temporal niche partitioning between moose and livestock breaks down under the weather conditions that are predicted to become more common as climate change, potentially increasing wildlife-livestock interactions in the future.
Forfattere
Boris Fuchs Kristin Sørheim Mattheo Chincarini Asgeir Bjarnason Emma Brunberg Solveig S. Stubsjøen Barbara Zimmermann Unni Støbet Lande Svein-Olaf Hvasshovd Kjell Bratbergsengen Lise GrøvaSammendrag
Det er ikke registrert sammendrag