Institutt for arktisk og marin biologi: Nye registreringer
Viser treff 1461-1480 av 2078
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The use of the nest for parental roosting and thermal consequences of the nest for nestlings and parents
(Journal article; Tidsskriftartikkel; Peer reviewed, 2017-11-07)Abstract<br> At temperate latitudes, altricial birds and their nestlings need to handle night temperatures well below thermoneutrality during the breeding season. Thus, energy costs of thermoregulation might constrain nestling growth, and low nocturnal temperatures might require resources that parents could otherwise have invested into nestlings during the day. To manipulate parental work rate, we ... -
Circumpolar dynamics of a marine top-predator track ocean warming rates.
(Journal article; Tidsskriftartikkel; Peer reviewed, 2017-04-07)Global warming is a nonlinear process, and temperature may increase in a stepwise manner. Periods of abrupt warming can trigger persistent changes in the state of ecosystems, also called regime shifts. The responses of organisms to abrupt warming and associated regime shifts can be unlike responses to periods of slow or moderate change. Understanding of nonlinearity in the biological responses to ... -
Elucidating the Behavior of Cyclic Volatile Methylsiloxanes in a Subarctic Freshwater Food Web: A Modeled and Measured Approach
(Journal article; Tidsskriftartikkel; Peer reviewed, 2017-10-05)Cyclic volatile methylsiloxanes (cVMS) are used in personal care products and emitted to aquatic environments through wastewater effluents, and their bioaccumulation potential is debated. Here, a new bentho-pelagic version of the ACC-HUMAN model was evaluated for polychlorinated biphenyls (PCBs) and applied to cVMS in combination with measurements to explore their bioaccumulation behavior in a ... -
Not only mosses: lemming winter diets as described by DNA metabarcoding
(Journal article; Tidsskriftartikkel; Peer reviewed, 2017-04-01)The temporal dynamics of most tundra food webs are shaped by the cyclic population dynamics of lemmings. While processes during winter may be behind the recent disruptions of lemming cycles, lemming winter ecology is poorly known. We present here the first DNA metabarcoding data on the winter diet of Norwegian lemmings (Lemmus lemmus), based on feces collected after a winter of population ... -
Polyunsaturated fatty acids in freshwater fishes increase with total lipids irrespective of feeding sources and trophic position
(Journal article; Tidsskriftartikkel; Peer reviewed, 2017-04-03)Trophic transfer and retention of dietary compounds are vital for somatic development, reproduction, and survival of aquatic consumers. In this field study, stable carbon and nitrogen isotopes, and fatty acids (FA) contents in invertebrates and fishes of pre-alpine Lake Lunz, Austria, were used to (1) identify the resource use and trophic level of Arctic charr (Salvelinus alpinus), pike (Esox lucius), ... -
Allometric trajectories of body and head morphology in three sympatric Arctic charr (Salvelinus alpinus (L.)) morphs
(Journal article; Tidsskriftartikkel; Peer reviewed, 2017-08-08)A study of body and head development in three sympatric reproductively isolated Arctic charr (Salvelinus alpinus (L.)) morphs from a subarctic lake (Skogsfjordvatn, northern Norway) revealed allometric trajectories that resulted in morphological differences. The three morphs were ecologically assigned to a littoral omnivore, a profundal benthivore and a profundal piscivore, and this was confirmed ... -
The trade-off between fecundity and egg size in a polymorphic population of Arctic charr (Salvelinus alpinus (L.)) in Skogsfjordvatn, subarctic Norway
(Journal article; Tidsskriftartikkel; Peer reviewed, 2017-02-26)Reproductive traits differ between intralacustrine Arctic charr morphs. Here, we ex - amine three sympatric lacustrine Arctic charr morphs with respect to fecundity, egg size and spawning time/site to assess reproductive investments and trade- offs, and possible fitness consequences. The littoral omnivore morph (LO- morph) utilizes the upper water for feeding and reproduction and spawn ... -
Changed Arctic-alpine food web interactions under rapid climate warming: implication for ptarmigan research
(Journal article; Tidsskriftartikkel; Peer reviewed, 2017-06-05)Ptarmigan are herbivorous birds that are year-round residents of alpine and arctic ecosystems — presently subjected to the most rapid climate warming on earth. Yet, compared to other bird taxa there has been little climate impact research on ptarmigan. Ptarmigan population dynamics, in particular in the sub/low-arctic, appears to be strongly influenced by complex interactions with a suite of ... -
Life cycle impact assessment in the arctic: Challenges and research needs
(Journal article; Tidsskriftartikkel; Peer reviewed, 2017-09-08)Life cycle assessment (LCA) is increasingly used for environmental assessment of products and production processes to support environmental decision-making both worldwide and in the Arctic. However, there are several weaknesses in the impact assessment methodology in LCA, e.g., related to uncertainties of impact assessment results, absence of spatial differentiation in characterization modeling, and ... -
Long-term environmental monitoring for assessment of change: measurement inconsistencies over time and potential solutions
(Journal article; Tidsskriftartikkel; Peer reviewed, 2017-10-30)The importance of long-term environmental monitoring and research for detecting and understanding changes in ecosystems and human impacts on natural systems is widely acknowledged. Over the last decades, a number of critical components for successful long-term monitoring have been identified. One basic component is quality assurance/quality control protocols to ensure consistency and comparability ... -
Microbial eukaryotes in an arctic under-ice spring bloom north of Svalbard
(Journal article; Tidsskriftartikkel; Peer reviewed, 2017-06-28)Microbial eukaryotes can play prominent roles in the Arctic marine ecosystem, but their diversity and variability is not well known in the ice-covered ecosystems. We determined the community composition of microbial eukaryotes in an Arctic under-ice spring bloom north of Svalbard using metabarcoding of DNA and RNA from the hypervariable V4 region of 18S nrDNA. At the two stations studied, the ... -
Diet and metabolic state are the main factors determining concentrations of perfluoroalkyl substances in female polar bears from Svalbard
(Journal article; Tidsskriftartikkel; Peer reviewed, 2017-06-03)Perfluoroalkyl substances (PFASs) have been detected in organisms worldwide, including Polar Regions. The polar bear (Ursus maritimus), the top predator of Arctic marine ecosystems, accumulates high concentrations of PFASs, which may be harmful to their health. The aim of this study was to investigate which factors (habitat quality, season, year, diet, metabolic state [i.e. feeding/fasting], breeding ... -
Thermal thresholds of phytoplankton growth in polar waters and their consequences for a warming polar ocean
(Journal article; Tidsskriftartikkel; Peer reviewed, 2017-06-02)Polar areas are experiencing the steepest warming rates on Earth, a trend expected to continue in the future. In these habitats, phytoplankton communities constitute the basis of the food web and their thermal tolerance may dictate how warming affects these delicate environments. Here, we compiled available data on thermal responses of phytoplankton growth in polar waters. We assembled 53 ... -
Sea trout adapt their migratory behaviour in response to high salmon lice concentrations
(Journal article; Tidsskriftartikkel; Peer reviewed, 2017-11-21)Sea trout face growth–mortality trade-offs when entering the sea to feed. Salmon lice epizootics resulting from aquaculture have shifted these trade-offs, as salmon lice might both increase mortality and reduce growth of sea trout. We studied mortality and behavioural adaptations of wild sea trout in a large-scale experiment with acoustic telemetry in an aquaculture intensive area that was fallowed ... -
Potentiation of ecological factors on the disruption of thyroid hormones by organo-halogenated contaminants in female polar bears (Ursus maritimus) from the Barents Sea.
(Journal article; Tidsskriftartikkel; Peer reviewed, 2017-06-11)As apex predators, polar bears (Ursus maritimus) are among the most heavily polluted organisms in the Arctic. In addition to this anthropogenic stressor, climate warming has been shown to negatively affect their body condition, reproductive output and survival. Among potential underlying physiological mechanisms, thyroid hormones (THs), which control thermoregulation, metabolism and reproduction, ... -
Continuous daylight in the high-Arctic summer supports high plankton respiration rates compared to those supported in the dark
(Journal article; Tidsskriftartikkel; Peer reviewed, 2017-04-28)Plankton respiration rate is a major component of global CO2 production and is forecasted to increase rapidly in the Arctic with warming. Yet, existing assessments in the Arctic evaluated plankton respiration in the dark. Evidence that plankton respiration may be stimulated in the light is particularly relevant for the high Arctic where plankton communities experience continuous daylight in spring ... -
Elevationally biased avian predation as a contributor to the spatial distribution of geometrid moth outbreaks in sub-arctic mountain birch forest
(Journal article; Tidsskriftartikkel; Peer reviewed, 2017-04-03)1. Population dynamics and interactions that vary over a species’ range are of particular importance in the context of latitudinal clines in biological diversity.Winter moth (Operophtera brumata) and autumnal moth (Epirrita autumnata) are two species of eruptive geometrids that vary widely in outbreak tendency over their range, which generally increases from south to north and with elevation. 2. ... -
Homage to Hersteinsson and Macdonald: climate warming and resource subsidies cause red fox range expansion and Arctic fox decline
(Journal article; Tidsskriftartikkel; Peer reviewed, 2017-08-16)Climate change can have a marked effect on the distribution and abundance of some species, as well as their interspecific interactions. In 1992, before ecological effects of anthropogenic climate change had developed into a topical research field, Hersteinsson and Macdonald published a seminal paper hypothesizing that the northern distribution limit of the red fox (Vulpes vulpes) is determined ... -
Snowmobile impact on diurnal behaviour in the Arctic fox
(Journal article; Tidsskriftartikkel; Peer reviewed, 2017-08-16)As tourism increases globally, studies have documented impacts on wildlife from anthropogenic disturbances. In this observational experiment we aimed to investigate if snowmobile traffic affected the diurnal activity of Arctic fox in High Arctic Svalbard. We conducted the study in two areas in Svalbard, one control area with low snowmobile traffic and one experimental area with high snowmobile ... -
Ecosystem drivers of an Arctic fox population at the western fringe of the Eurasian Arctic
(Journal article; Tidsskriftartikkel; Peer reviewed, 2017-08-16)The distribution of traditional breeding dens on the Varanger Peninsula (70–71°N) in northernmost Fennoscandia indicates that this area once harboured a large Arctic fox population. Early 20th century naturalists regarded the coastal tundra of the Fennoscandian Low Arctic to be a stronghold for the species. At the start of our research in 2004, however, the local Arctic fox population was ...