Bård-Jørgen Bårdsen

Bård-Jørgen Bårdsen
Norwegian Institute for Nature Research | NINA · Department of Arctic Ecology

Philosophiae doctor (PhD)

About

103
Publications
13,148
Reads
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1,590
Citations
Citations since 2017
34 Research Items
941 Citations
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Introduction
My primary research interests include evolution, population ecology and multidisciplinary research (ecology-anthropology) focusing on how environmental conditions in combination with anthropogenic impacts affect living organisms. I am particularly interested in understanding how environmental conditions and density dependence together with individual reproductive strategies interacts in shaping biological populations.
Additional affiliations
January 2015 - present
Norwegian Institute for Nature Research
Position
  • Senior Researcher
January 2010 - December 2014
February 2009 - December 2009
Education
January 2005 - January 2009
Department of Biology, Faculty of Science, University of Tromsø
Field of study
  • Biology
January 2001 - July 2003
Department of Biology, Faculty of Science, University of Tromsø
Field of study
  • Biology

Publications

Publications (103)
Article
Full-text available
If we want to understand how climate change affects long-lived organisms, we must know how individuals allocate resources between current reproduction and survival. This trade-off is affected by expected environmental conditions, but the extent to which density independent (DI) and density dependent (DD) processes interact in shaping individual lif...
Article
Full-text available
Spatiotemporal reindeer population fluctuations are a result of multiple factors that working in concert affecting the structure and functioning of many Arctic and Sub-Arctic ecosystems. We investigated the population dynamics of Swedish semi-domestic reindeer from 1945 to 2012 at the reindeer herding district-level (Sameby) to identify possible po...
Article
When reproduction competes with the amount of resources available for survival during an unpredictable nonbreeding season, individuals should adopt a risk-sensitive regulation of their reproductive allocation. We tested this hypothesis on female reindeer (Rangifer tarandus), which face a trade-off between reproduction and acquisition of body reserv...
Article
Full-text available
A growing body of evidence shows that for nomadic pastoralists herd accumulation is an efficient strategy for buffering environmental variation and maximizes long-term survival. Pastoralists may thus view livestock as investments, or ‘banks on the hoof,’ that work as insurance against unpredictable environmental conditions. This perspective differs...
Article
Full-text available
Cooperative behaviors evolve by ultimately increasing the inclusive fitness of performers as well as recipients of those behaviors. Such increases can occur via direct or indirect fitness benefits, theoretically explained by reciprocal altruism and kin selection, respectively. However, humans are known for cooperating with individuals who are not n...
Article
Full-text available
Hunter-collected data and samples are used as indices of population performance, and monitoring programs often take advantage of such data as ecological indicators. Here, we establish the relationships between measures of skeleton size (lower jawbone length and hind-leg length) and autumn carcass mass of slaughtered individuals of known age and sex...
Technical Report
Full-text available
Scientific Opinion of the Panel on Biodiversity of the Norwegian Scientific Committee for Food and Environment
Article
To assess how climate-sensitive factors may affect the exposure to organochlorines (OCs) and perfluoroalkyl substances (PFASs), we monitored concentrations in eggs of the common goldeneye (Bucephala clangula) over two decades (1999–2019) in central Norway. The goldeneye alternates between marine and freshwater habitats and is sensitive to climate v...
Article
Full-text available
The asymmetric grandparental investment in humans may ultimately be explained by the paternity uncertainty hypothesis. The proximate mechanisms leading to grandparental bias in investment in grandchildren are, however, unclear. In a study of 233 males and females with an opposite sexed sibling, we examined whether comments on resemblance regarding...
Article
Insight into processes determining the exposure of organohalogenated contaminants (OHCs) in wildlife might be gained from comparing predators in different ecosystems. This study compared two avian predator species with similar food chain lengths: the goldeneye duck (Bucephala clangula) and the tawny owl (Strix aluco) breeding in adjacent freshwater...
Article
The majority of the world's seabirds show substantial population declines, but a detailed understanding of the phenomenon is lacking. A potentially important mechanism that has received momentum lately is nest predation. This study aimed to assess the population viability of a threatened population of the lesser black‐backed gull Larus fuscus fuscu...
Article
Full-text available
Many seabird populations suffer heavily from the destruction of nests by generalist predators. In this study, we analyzed 16 years of data (2005–2020) on the reproductive output of the northern Lesser Black-backed Gull (Larus fuscus fuscus) at Horsvær, the largest assemblage of this subspecies in Norway (up to ca. 400 pairs), in relation to the occ...
Article
Full-text available
Fourteen legacy organochlorine contaminants (OCs) and twelve perfluorinated substances (PFASs) were measured in eggs of tawny owls (Strix alueco) in central Norway (1986 2019). We expected OCs to have reached stable equilibrium levels due to bans, and that recent phase‐out of some PFASs would have slowed the increase of these compounds⊡ ΣOC compris...
Article
Full-text available
Telomeres are used as biomarkers of vertebrate health because of the link between their length, lifespan, and survival. Exposure to environmental stressors appears to alter telomere dynamics, but little is known about telomere length and persistent organic pollutant (POP) exposure in wildlife. The white-tailed eagle (WTE; Haliaeetus albicilla) is a...
Article
Full-text available
Kin relations have a strong theoretical and empirical basis for explaining cooperative behavior. Nevertheless, there is growing recognition that context—the cooperative environment of an individual—also shapes the willingness of individuals to cooperate. For nomadic pastoralists in Norway, cooperation among both kin and non-kin is an essential pred...
Preprint
Social inequality is pervasive in contemporary human societies. Nevertheless, there is a view that livestock, as the primary source of wealth, limits the development of inequalities, making pastoralism unable to support complex or hierarchical organisations. Thus, complex nomadic pastoral organisation is predominantly caused by external factors, i....
Article
Full-text available
The Sami siida has been described as an organizational institution tailored to meet the dynamic demands of reindeer herding. Historically, it has been characterized as a relatively small group based on kinship. It was formed around a core sibling group and distinguished by a norm of equality where herding partners were equals regardless of social s...
Article
Full-text available
Susceptibility of cervids to Chronic Wasting Disease (CWD), a prion disease, can be modulated by variations in the prion protein gene (PRNP), encoding the cellular prion protein (PrPC). In prion diseases, PrPC is conformationally converted to pathogenic conformers (PrPSc), aggregates of which comprise infectious prions. CWD has recently been observ...
Article
Full-text available
We have analyzed DNA microsatellites and the mitochondrial control region in reindeer from 31 different husbandry areas in Norway, Sweden, and Finland in order to better understand the processes that underlie the genetic variability of the Nordic domestic herds. The distinct differentiation found in the nuclear markers but less so in the mitochondr...
Article
Lesser Black-backed Gulls (Larus fuscus fuscus) were studied over 10 breeding seasons (2005-2014) to assess factors influencing nesting distribution among 7 subcolonies with two distinct habitats (open-rocky or vegetated) in an archipelago on the Norwegian Coast. The study was divided into an early (2005-2008) and late period (2009-2014), depending...
Article
Full-text available
• Warming temperatures resulting from climate change may alter the distribution and abundance of many freshwater fish species, especially those in northern latitudes. Owing to interspecific differences in temperature adaptations and tolerances, warming may lead to changes in the fish community as a result of shifts in the abundance of co‐existing s...
Article
Full-text available
Apex predators are characterized by high levels of biomagnifying organohalogenated contaminants (OHCs) which have been found to induce detrimental health effects in wildlife, such as immune system impairment. The leukocyte coping capacity (LCC) assay is a functional real-time measure of an innate immune response essential in pathogen resistance, kn...
Preprint
The Saami siida has been described as an organisational institution tailored to meet the dynamic demands of reindeer herding. Historically, it has been characterised as a relatively small group based on kinship. It was formed around a core sibling group and distinguished by a norm of equality where herding partners were equals regardless of social...
Article
Full-text available
Understanding the spatiotemporal patterns of legacy organochlorines (OCs) is often difficult because monitoring practices differ among studies, fragmented study periods, and unaccounted confounding by ecological variables. We therefore reconstructed long-term (1939–2015) and large-scale (West Greenland, Norway, and central Sweden) trends of major l...
Article
The white-tailed eagle (Haliaeetus albicilla) in Scandinavia has suffered from impaired reproduction due to high exposure to industrial pollution between the 1960s and 1980s. While population numbers are rising again, new contaminants, such as per- and polyfluoroalkyl substances (PFAS), are increasingly found in high trophic avifauna and are of con...
Article
Full-text available
Landscape changes, such as habitat loss and fragmentation, subdivide wild populations, reduce their size, and limit gene flow. These changes may further lead to depletion of genetic variation within populations as well as accelerating differentiation among populations. As a migratory species requiring large living areas, wild reindeer (Rangifer tar...
Article
The spatiotemporal trends of mercury (Hg) are crucial for the understanding of this ubiquitous and toxic contaminant. However, uncertainties often arise from comparison among studies using different species, analytical and statistical methods. The long-term temporal trends of Hg exposure were reconstructed for a key sentinel species, the white-tail...
Article
Full-text available
Pastoralists rely on networks of cooperating households containing relatives and others to help with production and various other daily activities. To understand how socioecological differences and commonalities affect different social networks, we compared cooperative decision-making using gift games for 755 people working in herding groups across...
Article
Full-text available
Negative effects of long‐transported pollutants, such as many persistent organic pollutants (POPs), on seabirds and other top predators have been documented for decades. Yet, the concentrations, and hence, the negative impacts of many POPs have recently declined in the Northern Hemisphere. However, organisms are exposed to multiple stressors and th...
Article
Full-text available
Cooperation evolves on social networks and is shaped, in part, by norms: beliefs and expectations about the behaviour of others or of oneself. Networks of cooperative social partners and associated norms are vital for pastoralists, such as Saami reindeer herders in northern Norway. However, little is known quantitatively about how norms structure p...
Data
Supplementary Information for ‘The narrow gap between norms and cooperative behaviour in a reindeer herding community‘
Technical Report
Full-text available
Formålet med prosjektet var å identifisere ulike faktorer som kunne påvirke velferd hos tamrein, og som kunne implementeres i produksjonssystemene, på beite, i gjerdet, på slakteriet, gjennom produktmerking og fremtidige kvalitetssikringssystemer. I den senere tid har det vært et økt fokus på dyrehelse og -velferd i reindrifta. Det har for eksempel...
Article
Full-text available
Many social interactions create a tension between individual and collective interests, known as social dilemmas. Pastoralists, whose livelihoods depend on cooperation within and between herding groups, face a range of social dilemmas in their daily lives. Evolutionary theory predicts that social dilemmas will be solved (i.e. individuals will cooper...
Article
The present study explored short-term temporal variations in circulating concentrations of three legacy organochlorines (OCs) with different physicochemical properties (polychlorinated biphenyl 153 [PCB-153], p,p'-dichlorodiphenyldichloroethylene [DDE], and hexachlorobenzene [HCB]) in breeding kittiwakes (Rissa tridactyla) in a colony in Svalbard (...
Article
TheArcticisbecomingwarmeratahighrate,andcontractionsintheextentofseaicearecurrentlychangingthehabitatsofmarinetop-predatorsdependentonice.Polarbears(Ursusmaritimus)dependonseaiceforhuntingseals.Forthesetop-predators,longerice-freeseasonsarehypothesizedtoforcethebearstohuntforalternativeterrestrialfood,suchaseggsfromcolonialbreedingbirds.Weanalyzedt...
Article
Full-text available
The Arctic is becoming warmer at a high rate, and contractions in the extent of sea ice are currently changing the habitats of marine top-predators dependent on ice. Polar bears (Ursus maritimus) depend on sea ice for hunting seals. For these top-predators, longer ice-free seasons are hypothesized to force the bears to hunt for alternative terrestr...
Technical Report
https://www.miljodirektoratet.no/globalassets/publikasjoner/m396/m396.pdf
Article
Mesocarnivores increase in number and geographic range in human-disturbed ecosystems with cascading negative impact on biodiversity. To mitigate such impacts it is essential to identify the proximate causes of such mesocarnivore releases. Here we assess to what extent increased partial migration in semi-domesticated tundra reindeer induce a respons...
Article
Full-text available
Blue mussels, Mytilus edulis, serve as second intermediate hosts for several trematode species, but little is known about the mechanisms underlying parasite infections in mussels. To reveal these mechanisms, the prevalence and intensity of trematode larvae (metacercariae in species of Gymnophallus, Himasthla and Renicola) were examined in blue muss...
Technical Report
Full-text available
Adventdalsdeltaet er et viktig beiteområde for fjæreplytt, og denne tallrike vadefuglen bruker Adventdalsdeltaet fra mai til oktober. Antallet fjæreplytt har en karakteristisk topp på våren (mai-juni) og på høsten (overgangen september-oktober). Opp mot 2000 individer kan oppholde seg i deltaet samtidig. Sesongdynamikken kan forstås som en veksling...
Conference Paper
Full-text available
Cooperative behaviours must ultimately increase the inclusive fitness of actors as well as recipients in order to evolve. At the proximate level, mechanisms for encouraging and maintaining cooperation include kin discrimination, limited dispersal as well as direct and indirect reciprocity, among others. Here, we aim to quantify the relative importa...
Article
Full-text available
For long-lived organisms, the fitness value of survival is greater than that of current reproduction. Asymmetric fitness rewards suggest that organisms inhabiting unpredictable environments should adopt a risk-sensitive life history, predicting that it is adaptive to allocate resources to increase their own body reserves at the expense of reproduct...
Data
Full-text available
Temporal trends in climate and reindeer abundance.
Data
Full-text available
Using GAMs to assess temporal trends.
Technical Report
Full-text available
I prosjektet har vi vist at innsamling av underkjever og tilhørende jaktrapporter (1983-2012) fra jakten på svalbardrein gir et godt bilde av reinens tilstand (kroppsstørrelse, vekstvilkår og helse) og bestandsutvikling. Slik individbasert informasjon er egnet for å overvåke og oppdage endringer i bestandene som følge av både variasjon i klima, tet...
Article
In the recent decades, the atmospheric deposition of many metals has declined in northern Europe, mostly due to reductions of emissions in other parts of the Europe. However, less is known about the temporal trends at higher trophic levels in terrestrial food chains. In this study we measured 39 different essential and non-essential elements in taw...
Article
The extent to which persistent organic pollutants (POPs) with different physicochemical properties originated from the food (dietary input) was assessed in raptor nestlings. Lipophilic polychlorinated biphenyl (PCB) 153, 1-dichloro-2,2-bis (p-chlorophenyl) ethylene (p,p'-DDE) and hexachlorobenzene (HCB), and protein-bound perfluorooctane sulfonate...
Article
Full-text available
Analysing the effect of pastoral risk management strategies provides insights into a system of subsistence that have persevered in marginal areas for hundreds to thousands of years and may shed light into the future of around 200 million households in the face of climate change. This study investigated the efficiency of herd accumulation as a buffe...
Article
Full-text available
Anthropogenic impact on the environment and wildlife are multifaceted and far-reaching. On a smaller scale, controlling for predators has been increasing the yield from local natural prey resources. Globally, human-induced global warming is expected to impose severe negative effects on ecosystems, an effect that is expected to be even more pronounc...
Data
Full-text available
Finding the correct variance structure. This text explores models with different variance structures in order to assess if violations of the homoscedastic assumption altered the conclusions presented in the main text. (PDF)
Data
Full-text available
Study design and the reindeer husbandry. This text provides a more detailed description of the study design as well as the reindeer husbandry in Norway. (PDF)
Data
Is there really a ‘collapse’ in reindeer abundance? This text investigates temporal trends in low points of reindeer abundance from 1845–2000. (PDF)
Data
Full-text available
Possible grouping effects. This text investigates possible grouping effects, e.g. differences between summer districts with respect to natural and/or social factors. (PDF)
Data
Reported loss. This text replicates the analysis pertaining to loss presented in the main text but where ‘reported loss’ is used as a response. (PDF)
Article
Full-text available
Large herbivores living in seasonal environments are generally food-limited through density dependence and climatic factors. This may result in starvation and increased mortality in winter and reduced fecundity the following summer. Variability in winter conditions has the potential to create persistent fitness differences at the cohort- and the in...