Publications

abomasal nematodes of the svalbard reindeer (rangifer tarandus platyrhynchus vrolik).	six species of abomasal nematodes were recovered from svalbard reindeer, marshallagia marshalli and ostertagia grühneri were more prevalent than skrjabinagia lyrata, teladorsagia circumcincta, ostertagia occidentalis and ostertagia trifurcata. of 24 reindeer examined all harbored adult abomasal nematodes. there was no significant difference in intensity of infection between winter (april) and autumn (october) for either adult males or females. in winter, intensity of infection of adult males was ...	1983	6887429
chromosome aberrations in norwegian reindeer following the chernobyl accident.	chromosome analyses were carried out on peripheral blood lymphocytes of semi-domestic reindeer in norway which had been exposed to varying amounts of radiocesium emanating from the chernobyl accident. the sampling was done in the period 1987-1990. the material included 192 reindeer, originating from four herds in central norway, an area considerably affected by fallout from the chernobyl accident, and from three herds in northern norway which was unaffected by fallout from the accident. signific ...	1995	7700280
dietary and nutrient intake of a sami population living in traditional reindeer herding areas in north norway: comparisons with a group of norwegians.	the samis are an ethnic minority living in the northern region of norway, sweden, finland and russia. traditionally the samis made their living from reindeer herding with some fishing and agriculture. earlier studies have shown that their diet consisted of large amounts of reindeer meat, some fish and wild berries with low intakes of other fruits, vegetables and dairy products. due to the introduction of technical improvements like snowmobiles and terrain vehicles which makes moving with the her ...	1999	10429341
dna evidence that marshallagia marshalli ransom, 1907 and m. occidentalis ransom, 1907 (nematoda: ostertagiinae) from svalbard reindeer are conspecific.	the gastro-intestinal parasitic nematodes of ruminants marshallagia marshalli and m. occidentalis are morphs of a single species according to indirect evidence. in this study, their taxonomic status and molecular identification were assessed more directly in isolates from the abomasal nematode community of svalbard reindeer using genetic data. dna sequences of the first and second internal transcribed spacers of nuclear ribosomal rna genes were obtained from individual nematodes by the polymeras ...	2001	11586078
seroprevalence of antibodies to salmonella spp in semidomesticated reindeer in norway, determined by enzyme-linked immunosorbent assay.	an indirect elisa was developed as a possible tool to detect the seroprevalence of antibodies to salmonella spp in semidomesticated reindeer. to cover a broad spectrum of serogroups a lipopolysaccharide mix of s. typhimurium and s. choleraesuis was used as antigen in this pilot study. sera from 31 culture-negative reindeer with no clinical or historical evidence of salmonellosis were used as negative serum control. after immunisation with an inactivated s. typhimurium vaccine, pooled sera from 6 ...	2002	12357671
concentrations of 137cs in lynx (lynx lynx) in relation to prey choice.	concentrations of (137)cs were determined in 747 lynxes killed in norway during the period 1986-2001. highly variable (137)cs concentrations and aggregated transfer coefficient values were observed, probably caused by variable (137)cs concentrations in prey and the lynx's extensive home ranges and roaming distances. adult lynxes had higher (137)cs concentrations than sub-adults, and lynxes killed in regions with extensive reindeer grazing areas were more contaminated than others. a model with (1 ...	2005	15653191
continuous and discrete extreme climatic events affecting the dynamics of a high-arctic reindeer population.	climate at northern latitudes are currently changing both with regard to the mean and the temporal variability at any given site, increasing the frequency of extreme events such as cold and warm spells. here we use a conceptually new modelling approach with two different dynamic terms of the climatic effects on a svalbard reindeer population (the brøggerhalvøya population) which underwent an extreme icing event ("locked pastures") with 80% reduction in population size during one winter (1993/94) ...	2005	16010537
sexual dimorphism and intercohort variation in reindeer calf antler length is associated with density and weather.	we analysed intercohort variability of live weight and antler length of 5,123 reindeer calves. we further assessed the influence of climate and density on the interannual variation in antler length, and discussed sex-specific resource allocation and response to climate variability. antler length varied significantly among years and between sexes, with interaction between year and sex. body weight and antler length were highly positively correlated, showed similar intercohort variability, and had ...	2005	16025353
campylobacter spp., salmonella spp., verocytotoxic escherichia coli, and antibiotic resistance in indicator organisms in wild cervids.	faecal samples were collected, as part of the national health surveillance program for cervids (hop) in norway, from wild red deer, roe deer, moose and reindeer during ordinary hunting seasons from 2001 to 2003. samples from a total of 618 animals were examined for verocytotoxic e. coli (vtec); 611 animals for salmonella and 324 animals for campylobacter. a total of 50 samples were cultivated from each cervid species in order to isolate the indicator bacterial species e. coli and enterococcus fa ...	2005	16108210
resistance to abomasal nematodes and individual genetic variability in reindeer.	resistance to parasites is believed to have a widespread influence on demographic and adaptive processes. in systems where parasites impose a fitness cost on their host, heterozygotes may be selected because they are more resistant to parasites than homozygotes. our objective was to assess the relationships between genomewide individual heterozygosity and abomasal nematode burdens in female svalbard reindeer (rangifer tarandus platyrhynchus) after the effects of host age, locality, season, and y ...	2005	16262866
lifestyle, genetics, and disease in sami.	to present a summary of the lifestyle, genetic origin, diet, and disease in the population of sami, indigenous people of northern fennoscandia.	2006	16909452
mortality in the sami population of north norway, 1970-98.	the pattern of mortality among many groups of indigenous people has been shown to be disadvantageous in comparison with the general population. knowledge regarding causes of death among the sami population in the northern part of norway is limited. the sami constitute an ethnic minority whose lifestyle diverges from that of the rest of the population.	2007	17530553
dietary patterns in the population living in the sámi core areas of norway--the saminor study.	to identify dietary patterns and to investigate their association with selected life-style and demographic factors, ethnicity and self-perceived health. study design. population-based cross-sectional design, using food frequency questionnaires.	2008	18468261
molecular diversity of the rumen microbiome of norwegian reindeer on natural summer pasture.	the molecular diversity of the rumen microbiome was investigated in five semi-domesticated adult female norwegian reindeer (rangifer tarandus tarandus) grazing on natural summer pastures on the coast of northern norway (71.00 degrees n, 25.30 degrees e). mean population densities (numbers per gram wet weight) of methanogenic archaea, rumen bacteria and ciliate protozoa, estimated using quantitative real-time polymerase chain reaction (pcr), were 3.17x10(9), 5.17x10(11) and 4.02x10(7), respective ...	2009	18604648
the importance of marine vs. human-induced subsidies in the maintenance of an expanding mesocarnivore in the arctic tundra.	1. most studies addressing the causes of the recent increases and expansions of mesopredators in many ecosystems have focused on the top-down, releasing effect of extinctions of large apex predators. however, in the case of the northward expansion of the red fox into the arctic tundra, a bottom-up effect of increased resource availability has been proposed, an effect that can counteract prey shortage in the low phase of the multi-annual rodent cycle. resource subsidies both with marine and with ...	2011	21477201
diet and lifestyle of the sami of southern lapland in the 1930s-1950s and today.	objectives. to describe the lifestyle of the sami of southern lapland 50 to 70 years ago in relation to the present-day sami and non-sami populations and, thereby, to provide a basis for future studies of culturally related determinants of health and illness. study design. a qualitative analysis, and a quantitative comparison of sami and non-sami groups. methods. semi-structured interviews were conducted with 20 elderly sami concerning their parents' lifestyle and diet 50 to 70 years ago. questi ...	2011	21631968
antioxidant and other quality properties of reindeer muscle from two different norwegian regions.	the effects of origin, gender, age, and muscle type on chemical composition, colour, antioxidant status and sensory profile of reindeer muscles longissimus dorsi (ld) and semimembranosus (sm) from two production regions were investigated. for some variables, the comparison between reindeer and beef muscles was also included. muscles from north norway (nn) were darker and contained more myoglobin and moisture, and less protein and fat than muscles from mid norway (mn). oxygen radical absorbance c ...	2011	21669498
composition and some quality characteristics of the longissimus muscle of reindeer in norway compared to farmed new zealand red deer.	norwegian reindeer of finnmark county live under harsh conditions on extensive feed sources. thus the meat may have special qualities. m. longissimus lumborum from 30 animals was investigated with respect to carcass and meat quality and compositional/nutritional characteristics. meat from calves had a higher myofibrillar fragmentation index and tenderness, and had lighter, redder and more yellow colour than meat from adult reindeer. regarding nutritional compounds the meat from calves had lower ...	2011	21757298
incentives and regulations to reconcile conservation and development: thirty years of governance of the sami pastoral ecosystem in finnmark, norway.	incentive-based mechanisms are regarded as efficient instruments to reconcile conservation and development. this win-win objective has been difficult to accomplish; cross-compliance has, therefore, been suggested as a mechanism to ensure sustainability. cross-compliance, which requires producers to conform to production regulations and environmental standards to qualify for direct payments, has been a popular instrument in the common agricultural policy (cap) reform. since 1990, cross-compliance ...	2011	21745708
the importance of willow thickets for ptarmigan and hares in shrub tundra: the more the better?	in patchy habitats, the relationship between animal abundance and cover of a preferred habitat may change with the availability of that habitat, resulting in a functional response in habitat use. here, we investigate the relationship of two specialized herbivores, willow ptarmigan (lagopus lagopus) and mountain hare (lepus timidus), to willows (salix spp.) in three regions of the shrub tundra zone-northern norway, northern european russia and western siberia. shrub tundra is a naturally patchy h ...	2011	21833646
Density-dependence vs. density-independence - linking reproductive allocation to population abundance and vegetation greenness.	1. Recent studies have shown that optimal reproductive allocation depends on both climatic conditions and population density. We tested this hypothesis using six years of demographic data from eight reindeer (Rangifer tarandus) populations coupled with data on population abundance and vegetation greenness [measured using the Enhanced Vegetation Index (EVI)]. 2. Female spring body mass positively affected summer body mass gain, and lactating females were unable to compensate for harsh winters as ...	2011	21985598
Pestivirus and alphaherpesvirus infections in Swedish reindeer (Rangifer tarandus tarandus L.).	Herding semi-domesticated reindeer has economic and social value for Sami people in the northern territories of Fennoscandia. However, with the intensification of reindeer husbandry, interspecies transmission of pathogens between reindeer and domestic animals may become a problem, especially for countries such as Sweden, Norway, and Finland where pestivirus and alphaherpesvirus have been eradicated in domestic ruminants. This study, which included 1158 Swedish reindeer, showed relatively high pr ...	2011	22078277
development and application of a delayed-release anthelmintic intra-ruminal bolus system for experimental manipulation of nematode worm burdens.	in order to quantify the impact of parasites on host population dynamics, experimental manipulations that perturb the parasite-host relationship are needed but, logistically, this is difficult for wild hosts. here, we describe the use of a delayed-release anthelmintic delivery system that can be administered when the hosts can be captured and its activity delayed until a more appropriate period in the host-parasite cycle. our model system is svalbard reindeer infected with a nematode parasite, m ...	2012	22417532
congruent responses to weather variability in high arctic herbivores.	assessing the role of weather in the dynamics of wildlife populations is a pressing task in the face of rapid environmental change. rodents and ruminants are abundant herbivore species in most arctic ecosystems, many of which are experiencing particularly rapid climate change. their different life-history characteristics, with the exception of their trophic position, suggest that they should show different responses to environmental variation. here we show that the only mammalian herbivores on t ...	2012	23015455
metagenomics of the svalbard reindeer rumen microbiome reveals abundance of polysaccharide utilization loci.	lignocellulosic biomass remains a largely untapped source of renewable energy predominantly due to its recalcitrance and an incomplete understanding of how this is overcome in nature. we present here a compositional and comparative analysis of metagenomic data pertaining to a natural biomass-converting ecosystem adapted to austere arctic nutritional conditions, namely the rumen microbiome of svalbard reindeer (rangifer tarandus platyrhynchus). community analysis showed that deeply-branched cellu ...	2012	22701672
phenolic responses of mountain crowberry (empetrum nigrum ssp. hermaphroditum) to global climate change are compound specific and depend on grazing by reindeer (rangifer tarandus).	mountain crowberry (empetrum nigrum ssp. hermaphroditum) is a keystone species in northern ecosystems and exerts important ecosystem-level effects through high concentrations of phenolic metabolites. it has not been investigated how crowberry phenolics will respond to global climate change. in the tundra, grazing by reindeer (rangifer tarandus) affects vegetation and soil nutrient availability, but almost nothing is known about the interactions between grazing and global climate change on plant ...	2013	24287946
sunscreening fungal pigments influence the vertical gradient of pendulous lichens in boreal forest canopies.	pendulous lichens dominate canopies of boreal forests, with dark bryoria species in the upper canopy vs. light alectoria and usnea species in lower canopy. these genera offer important ecosystem services such as winter forage for reindeer and caribou. the mechanism behind this niche separation is poorly understood. we tested the hypothesis that species-specific sunscreening fungal pigments protect underlying symbiotic algae differently against high light, and thus shape the vertical canopy gradi ...	2014	25039211
"generality of mis-fit"? the real-life difficulty of matching scales in an interconnected world.	a clear understanding of processes at multiple scales and levels is of special significance when conceiving strategies for human-environment interactions. however, understanding and application of the scale concept often differ between administrative-political and ecological disciplines. these mirror major differences in potential solutions whether and how scales can, at all, be made congruent. as a result, opportunities of seeking "goodness-of-fit" between different concepts of governance shoul ...	2016	26939924
predicting the continuum between corridors and barriers to animal movements using step selection functions and randomized shortest paths.	the loss, fragmentation and degradation of habitat everywhere on earth prompts increasing attention to identifying landscape features that support animal movement (corridors) or impedes it (barriers). most algorithms used to predict corridors assume that animals move through preferred habitat either optimally (e.g. least cost path) or as random walkers (e.g. current models), but neither extreme is realistic. we propose that corridors and barriers are two sides of the same coin and that animals e ...	2016	25950737
how many routes lead to migration? comparison of methods to assess and characterize migratory movements.	decreasing rate of migration in several species as a consequence of climate change and anthropic pressure, together with increasing evidence of space-use strategies intermediate between residency and complete migration, are very strong motivations to evaluate migration occurrence and features in animal populations. the main goal of this paper was to perform a relative comparison between methods for identifying and characterizing migration at the individual and population level on the basis of an ...	2016	26412564
emission changes dwarf the influence of feeding habits on temporal trends of per- and polyfluoroalkyl substances in two arctic top predators.	we monitored concentrations of per- and polyfluoroalkyl substances (pfass) in relation to climate-associated changes in feeding habits and food availability in polar bears (ursus maritimus) and arctic foxes (vulpes lagopus) (192 plasma and 113 liver samples, respectively) sampled from svalbard, norway, during 1997-2014. pfass concentrations became greater with increasing dietary trophic level, as bears and foxes consumed more marine as opposed to terrestrial food, and as the availability of sea ...	2017	28918622
contrasting effects of summer and winter warming on body mass explain population dynamics in a food-limited arctic herbivore.	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 which should lead to heavier and more fertile individuals in the autumn. conversely, warm spells in winter with rainfall (rain-on-snow) can cause 'icing', restricting access to forage, resulting in starvation, lower survival and fecundity. as body condition is a 'barometer' of ene ...	2017	27426229