Artikler, rapporter og annet (arktisk og marin biologi): Recent submissions
Now showing items 241-260 of 1607
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Twig selection on mountain birch Betula pubescens by winter-feeding willow grouse Lagopus lagopus in a subarctic forest
(Journal article; Tidsskriftartikkel; Peer reviewed, 2023-02-06)In a subarctic forest at Kvaløya, northern Norway, willow grouse Lagopus lagopus fed at snow level by clipping bits of twigs from mountain birch Betula pubescens during winter. Birch has two types of twigs ending in a terminal bud: long twigs with a smooth bark, and short twigs with rings of thicker bark. The grouse selected ringed twigs above smooth twigs despite a surplus of smooth twigs in the ... -
Integrating Erosion Potential Model (EPM) and PAP/RAC Guidelines for Water Erosion Mapping and Detection of Vulnerable Areas in the Toudgha River Watershed of the Central High Atlas, Morocco
(Journal article; Tidsskriftartikkel; Peer reviewed, 2023-04-06)This study aimed to evaluate the extent and severity of water erosion in the Toudgha river catchment in the Central High Atlas of Morocco using two different erosion models, the Erosion Potential Model (EPM) and the Priority Actions Programme/Regional Activity Centre (PAP/RAC) model. From the modeling results, the catchment was affected by varying degrees of erosion, ranging from “very slight” ... -
Towards long-term records of rain-on-snow events across the Arctic from satellite data
(Journal article; Tidsskriftartikkel; Peer reviewed, 2023-02-21)Rain-on-snow (ROS) events occur across many regions of the terrestrial Arctic in mid-winter. Snowpack properties are changing, and in extreme cases ice layers form which affect wildlife, vegetation and soils beyond the duration of the event. Specifically, satellite microwave observations have been shown to provide insight into known events. Only Ku-band radar (scatterometer) has been applied so ... -
The plant vampire diaries: a historic perspective on Cuscuta research
(Journal article; Tidsskriftartikkel; Peer reviewed, 2023-03-08)The angiosperm genus <i>Cuscuta</i> lives as an almost achlorophyllous root- and leafless holoparasite and has therefore occupied scientists for more than a century. The ‘evolution’ of <i>Cuscuta</i> research started with early studies that established the phylogenetic framework for this unusual genus. It continued to produce groundbreaking cytological, morphological, and physiological insight ... -
Molecular phylogeny of the Orthalicoidea land snails: Further support and surprises
(Journal article; Tidsskriftartikkel; Peer reviewed, 2023-07-26)The superfamily Orthalicoidea comprises approximately 2,000 species of terrestrial gastropods, mostly concentrated in the Neotropics but also present in southern Africa and Oceania. We provide a multi-marker molecular phylogeny of this superfamily, reassessing its family- and genus-level classification. We exclude two families from the group, Odontostomidae and Vidaliellidae, transferring them to ... -
Novel frontier in wildlife monitoring: Identification of small rodent species from fecal pellets using near-infrared reflectance spectroscopy (NIRS)
(Journal article; Tidsskriftartikkel; Peer reviewed, 2023-03-19)Small rodents are prevalent and functionally important across the world's biomes, making their monitoring salient for ecosystem management, conservation, forestry, and agriculture. There is a growing need for cost-effective and noninvasive methods for large-scale, intensive sampling. Fecal pellet counts readily provide relative abundance indices, and given suitable analytical methods, feces could ... -
Multiproxy analyses of paleoenvironmental and paleoceanographic changes during the Danian-Selandian in East Central Sinai: An integrated stable isotope and planktic foraminiferal data
(Journal article; Tidsskriftartikkel; Peer reviewed, 2023-04-18)Forty-three planktic foraminifera samples from the Themed section (East Central Sinai; Egypt) spanning the Zone Parvularugoglobigerina eugubina (Pα) to the Subzone Acarinina subsphaerica (P4b) have been studied. Data from δ<sup>13</sup>C, δ18O, and planktic foraminifera-based species diversity, depth habitat, preference for warm and cool surface waters, and nutrients (oligotrophic, mesotrophic, ... -
Determination of growth, mass, and body mass index of harbour porpoises (Phocoena phocoena): Implications for conservational status assessment of populations
(Journal article; Tidsskriftartikkel; Peer reviewed, 2023-01-27)Longitudinal data on individual growth and seasonal changes in body mass, girth, and blubber thickness are rarely available for cetaceans, making it difficult to assess their population composition and individual nutritional condition. During different time intervals from 1997 to 2020, we collected longitudinal data on length, body mass, girth,and blubber thickness from seventeen harbour porpoises ... -
Hair cortisol concentration and body mass in moose (Alces alces) infested with deer keds (Lipoptena cervi)
(Journal article; Tidsskriftartikkel; Peer reviewed, 2020-07-01)The deer ked (<i>Lipoptena cervi</i>), a hematophagous ectoparasite of cervids, is currently spreading in Scandinavia, and the moose (<i>Alces alces</i>) is its main host. However, little is known about the impact of deer keds on moose. We analyzed the hair cortisol concentration (HCC) from 262 moose harvested in the fall in relation to age class, sex, body mass (BM), and deer ked infestation ... -
A serological screening for potential viral pathogens among semi-domesticated Eurasian tundra reindeer (Rangifer tarandus tarandus) in Finland
(Journal article; Tidsskriftartikkel; Peer reviewed, 2023-02-22)Reindeer herding and husbandry is a traditional and important livelihood in Fennoscandia, and about 200,000 semi-domesticated reindeer are herded in Finland. Climatic changes, leading to ice-locked winter pastures, and encroachment of pasture-land have led to changes in reindeer husbandry, increasing the extent of supplementary or full ration feeding, which has become very common in Finland. Keeping ... -
A Screening for Virus Infections among Wild Eurasian Tundra Reindeer (Rangifer tarandus tarandus) in Iceland, 2017–2019
(Journal article; Tidsskriftartikkel; Peer reviewed, 2023-01-23)A winter population of around 4000–5000 wild Eurasian tundra reindeer (<i>Rangifer t. tarandus</i>) in the eastern part of Iceland represents descendants from 35 semi-domesticated reindeer imported to Iceland from Finnmark county, Norway, in 1787. While previous studies have indicated that they host fewer parasite species as compared to reindeer in Fennoscandia, little information exists on their ... -
Spawning time in adult polar cod (Boreogadus saida) altered by crude oil exposure, independent of food availability
(Journal article; Tidsskriftartikkel; Peer reviewed, 2023-07-03)Fish early life stages are well known for their sensitivity to crude oil exposure. However, the effect of crude oil exposure on adults and their gametes during their spawning period is not well studied. Polar cod, a key arctic fish, may be at risk for crude oil exposure during this potentially sensitive life stage. Additionally, this species experiences lower food availability during their spawning ... -
What we do in the dark: Prevalence of omnivorous feeding activity in Arctic zooplankton during polar night
(Journal article; Tidsskriftartikkel, 2023-07-04)During the productive polar day, zooplankton and sea-ice amphipods fulfill a critical role in energy transfer from primary producers to higher trophic-level species in Arctic marine ecosystems. Recent polar night studies on zooplankton and sea-ice amphipods suggest higher levels of biological activity than previously assumed. However, it is unknown if these invertebrates maintain polar night activity ... -
New species of Miradiscops (Gastropoda: Scolodontidae) from Martinique
(Journal article; Tidsskriftartikkel, 2023-08-02)Only 17 endemic land snail species are known so far on the Lesser Antillean island of Martinique, most of which are macrogastropods that are easily visible, and thus, easily collectable. On the other hand, species of microgastropods remain undersampled and overlooked. Based on recently collected shells from Mount Vauclin, we describe a new species of Scolodontidae, Miradiscops madinina sp. nov. from ... -
Photoperiodism and overwintering in boreal and sub-Arctic Calanus finmarchicus populations
(Journal article; Tidsskriftartikkel; Peer reviewed, 2023-06-08)The copepod Calanus finmarchicus, a key species in the North Atlantic, generally spends the non-productive season by descending into deep waters and entering diapause, a physiological state characterized by reduced metabolism and arrested development. In the open ocean, overwintering depths are below 600 m, where temperature and light conditions are favourable to initiate diapause. However, C. ... -
Serological screening for tick-borne encephalitis virus in eight Norwegian herds of semi-domesticated reindeer
(Journal article; Tidsskriftartikkel; Peer reviewed, 2023-06-01)Tick-borne encephalitis virus (TBEV) is found in Ixodes ricinus ticks throughout the area where viable tick populations exist. In Norway, TBEV is found in I. ricinus from the south coast until Brønnøy municipality in Nordland County and the range of the vector is expanding due to changes in climate, vegetation, host animals and environmental conditions. TBEV might thus have the potential to establish ... -
High seasonal overlap in habitat suitability in a nonmigratory High Arctic ungulate
(Journal article; Tidsskriftartikkel; Peer reviewed, 2023-05-26)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 endemic wild Svalbard reindeer (Rangifer tarandus platyrhynchus). The High Arctic Svalbard tundra is currently subject to the fastest temperature increases on Earth, and reindeer ... -
Northern expansion is not compensating for southern declines in North American boreal forests
(Journal article; Tidsskriftartikkel; Peer reviewed, 2023-06-08)Climate change is expected to shift the boreal biome northward through expansion at the northern and contraction at the southern boundary respectively. However, biome-scale evidence of such a shift is rare. Here, we used remotely-sensed tree cover data to quantify temporal changes across theNorth American boreal biome from 2000 to . 2019. We reveal a strong northsouth asymmetry in tree cover change, ... -
Increased importance of cool-water fish at high latitudes emerges from individual-level responses to warming
(Journal article; Tidsskriftartikkel; Peer reviewed, 2023-06-06)High latitude ecosystems are experiencing the most rapid warming on earth, expected to trigger a diverse array of ecological responses. Climate warming affects the ecophysiology of fish, and fish close to the cold end of their thermal distribution are expected to increase somatic growth from increased temperatures and a prolonged growth season, which in turn affects maturation schedules, reproduction, ... -
Estimating the cumulative impact and zone of influence of anthropogenic features on biodiversity
(Journal article; Tidsskriftartikkel; Peer reviewed, 2023-06-02)1. The concept of cumulative impacts is widespread in policy documents, regu-lations and ecological studies, but quantification methods are still evolving. Infrastructure development usually takes place in landscapes with preexist-ing anthropogenic features. Typically, their impact is determined by computing the distance to the nearest feature only, thus ignoring the potential cumulative impacts of ...