The pollution fast-track to the arctic: how Southern wintering areas contribute to organochlorine loads in a migrant seabird breeding in the arctic.

This study examines how southern wintering areas may contribute to organochlorine (OCs) loads in arctic seabirds during breeding. Light-sensitive geolocators (GLS loggers) were deployed on Arctic skuas (Stercorarius parasiticus) in one high arctic and two subarctic colonies. Hexcahlorobenzene (HCB), Chlordanes, Mirex, p, p'-dichlorodiphenyldichloro- ethylene (p, p'-DDE), and Polychlorinated biphenyls (PCBs) were measured in the blood of breeding adults at the nest (58 individuals, a total of 128 samples) in northern Norway and Svalbard between 2009 and 2015.

Prevalence and density of Elaphostrongylus rangiferi larvae in faecal samples of semi-domestic reindeer (Rangifer tarandus tarandus) in Norway 2013-16.

Background: The reindeer brainworm, Elaphostrongylus rangiferi, is a protostrongylid parasite of reindeer that has caused severe disease outbreaks in reindeer husbandry. E. rangiferi is considered ubiquitous in Norway, though most published prevalence studies are from Finnmark county only.

Circumpolar Population Structure, Diversity and Recent Evolutionary History of the Bearded Seal in Relation to Past and Present Icescapes.

The Arctic environment plays a critical role in the global climate system and marine biodiversity. The region's ice-covered expanses provide essential breeding and feeding grounds for a diverse assemblage of marine species, who have adapted to thrive in these harsh conditions and consequently are under threat from global warming. The bearded seal (Erignathus barbatus), including two subspecies (E.

Kinship clustering within an ecologically diverse killer whale metapopulation.

Metapopulation dynamics can be shaped by foraging ecology, and thus be sensitive to shifts in prey availability. Genotyping 204 North Atlantic killer whales at 1346 loci, we investigated whether spatio-temporal population structuring is linked to prey type and distribution. Using population-based methods (reflecting evolutionary means), we report a widespread metapopulation connected across ecological groups based upon nuclear genome SNPs, yet spatial structuring based upon mitogenome haplotypes.

A transdisciplinary, comparative analysis reveals key risks from Arctic permafrost thaw.

Permafrost thaw poses diverse risks to Arctic environments and livelihoods. Understanding the effects of permafrost thaw is vital for informed policymaking and adaptation efforts. Here, we present the consolidated findings of a risk analysis spanning four study regions: Longyearbyen (Svalbard, Norway), the Avannaata municipality (Greenland), the Beaufort Sea region and the Mackenzie River Delta (Canada) and the Bulunskiy District of the Sakha Republic (Russia).

Increased fish abundance, biodiversity, and body size near a North Sea oil and gas platform.

In the North Sea, offshore oil and gas (O&G) platforms must be totally removed through decommissioning at the end of their productive life. However, the role of O&G platforms in marine ecosystems, especially for fish assemblages, is not well enough defined yet. Here, we document the association between an O&G platform in the North Sea and the fish assemblages along a distance gradient of 1-600 m from the platform.

Diet and trophic structure of fishes in the Barents Sea: between empty and full stomachs - large individual variability follows a common pattern.

More than 27,000 stomachs from 70 species of fish were collected from the Barents Sea in 2015. Quantitative stomach content expressed relative to the body weight of the predator fish (g g as %) varied by four to five orders of magnitude for six species with the largest sample size (Atlantic cod Gadus morhua, haddock Melanogrammus aeglefinus, Greenland halibut Reinhardtius hippoglossoides, long rough dab Hippoglossoides platessoides, polar cod Boreogadus saida, and Atlantic capelin Mallotus villosus). The quantitative stomach contents of individual fish followed a common and strict statistical relationship for predator species or groups of species (by families), and for prey categories across predator species.

Management Measures and Trends of Biological Invasions in Europe: A Survey-Based Assessment of Local Managers.

Biological invasions are a major threat to biodiversity, ecosystem functioning and nature's contributions to people worldwide. However, the effectiveness of invasive alien species (IAS) management measures and the progress toward achieving biodiversity targets remain uncertain due to limited and nonuniform data availability. Management success is usually assessed at a local level and documented in technical reports, often written in languages other than English, which makes such data notoriously difficult to collect at large geographic scales.

Quantitative analysis of the polar cod (Boreogadus saida) hepatic proteome highlights interconnected responses in cellular adaptation and defence mechanisms after dietary benzo[a]pyrene exposure.

Increased industrial offshore activities in northern waters raise the question of impact of polycyclic aromatic hydrocarbons (PAHs) on key Arctic marine species. One of these is the ecologically important polar cod (Boreogadus saida), which is the primary food source for Arctic marine mammals and seabirds. In the present work, we have conducted the first comprehensive proteomics study with this species by exploring the effects of dietary PAH exposure on the hepatic proteome, using benzo[a]pyrene (BaP) as a PAH model-compound.

Inefficient transfer of diatoms through the subpolar Southern Ocean twilight zone.

The Southern Ocean, a region highly vulnerable to climate change, plays a vital role in regulating global nutrient cycles and atmospheric CO via the biological carbon pump. Diatoms, photosynthetically active plankton with dense opal skeletons, are key to this process as their exoskeletons are thought to enhance the transfer of particulate organic carbon to depth, positioning them as major vectors of carbon storage. Yet conflicting observations obscure the mechanistic link between diatoms, opal and particulate organic carbon fluxes, especially in the twilight zone where greatest flux losses occur.

Haemoglobin revisited: delineating population structure with the world's first molecular genetic marker used in fisheries research.

When haemoglobin genotyping was implemented in the early 1960s to investigate population genetic structure in Atlantic cod (), it became one of the first molecular genetic markers deployed in fisheries research worldwide. However, its suitability was questioned due to its potential for selection. While the issue of neutrality concerned the first population geneticists, markers under selection are now routinely used to study population genetic structure.

Methane emissions from the Nord Stream subsea pipeline leaks.

The amount of methane released to the atmosphere from the Nord Stream subsea pipeline leaks remains uncertain, as reflected in a wide range of estimates. A lack of information regarding the temporal variation in atmospheric emissions has made it challenging to reconcile pipeline volumetric (bottom-up) estimates with measurement-based (top-down) estimates. Here we simulate pipeline rupture emission rates and integrate these with methane dissolution and sea-surface outgassing estimates to model the evolution of atmospheric emissions from the leaks.

Illuminating the multidimensional contributions of small-scale fisheries.

Sustainable development aspires to "leave no one behind". Even so, limited attention has been paid to small-scale fisheries (SSF) and their importance in eradicating poverty, hunger and malnutrition. Through a collaborative and multidimensional data-driven approach, we have estimated that SSF provide at least 40% (37.

Pervasive glacier retreats across Svalbard from 1985 to 2023.

A major uncertainty in predicting the behaviour of marine-terminating glaciers is ice dynamics driven by non-linear calving front retreat, which is poorly understood and modelled. Using 124919 calving front positions for 149 marine-terminating glaciers in Svalbard from 1985 to 2023, generated with deep learning, we identify pervasive calving front retreats for non-surging glaciers over the past 38 years. We observe widespread seasonal cycles in calving front position for over half of the glaciers.

How resistant is anammox biofilm against antibiotics: A special insight into anammox response towards fluoroquinolones.

Elevated concentrations of pharmaceutically active compounds (PhACs) in the water bodies are posing a serious threat to the aquatic microbiota and other organisms. In this context, anaerobic ammonium oxidizing (anammox) bacteria carry a great potential to degrade PhACs through their innate metabolic pathways. This study investigates the influence of short-term exposure to lower and higher concentrations (0.

Potential plant extinctions with the loss of the Pleistocene mammoth steppe.

During the Pleistocene-Holocene transition, the dominant mammoth steppe ecosystem across northern Eurasia vanished, in parallel with megafauna extinctions. However, plant extinction patterns are rarely detected due to lack of identifiable fossil records. Here, we introduce a method for detection of plant taxa loss at regional (extirpation) to potentially global scale (extinction) and their causes, as determined from ancient plant DNA metabarcoding in sediment cores (sedaDNA) from lakes in Siberia and Alaska over the past 28,000 years.

Sea urchin intestinal bacterial communities depend on seaweed diet and contain nitrogen-fixing symbionts.

Kelp deforestation by sea urchin grazing is a widespread phenomenon globally, with vast consequences for coastal ecosystems. The ability of sea urchins to survive on a kelp diet of poor nutritional quality is not well understood and bacterial communities in the sea urchin intestine may play an important role in digestion. A no-choice feeding experiment was conducted with the sea urchin Strongylocentrotus droebachiensis, offering three different seaweeds as diet, including the kelp Saccharina latissima.

Using a citizen science approach to assess nanoplastics pollution in remote high-altitude glaciers.

Nanoplastics are suspected to pollute every environment on Earth, including very remote areas reached via atmospheric transport. We approached the challenge of measuring environmental nanoplastics by combining high-sensitivity TD-PTR-MS (thermal desorption-proton transfer reaction-mass spectrometry) with trained mountaineers sampling high-altitude glaciers ("citizen science"). Particles < 1 μm were analysed for common polymers (polyethylene, polyethylene terephthalate, polypropylene, polyvinyl chloride, polystyrene and tire wear particles), revealing nanoplastic concentrations ranging 2-80 ng mL at five of 14 sites.

Post-testicular spermatozoa of a marine teleost can conduct cytoplasmic and mitochondrial translation.

Translational silence of spermatozoa has long been considered the norm in animals. However, studies in mammals have shown that the mitochondrial ribosomal machinery is selectively activated during capacitation in the female reproductive tract, while cytosolic ribosomes remain inactive. Here, using quantitative proteomics in a piscine model species, we show that proteins involved in mRNA processing and cytoplasmic translation are predominantly accumulated in immature spermatozoa within the extratesticular excurrent ducts, while those related to flagellar motility are enriched in ejaculated (mature) sperm.

Northern Scandinavian mountains supported by a low-grade eclogitic crustal keel.

Plate tectonics predicts that mountain ranges form by tectono-magmatic processes at plate boundaries, but high topography is often observed along passive margins far from any plate boundary. The high topography of the Scandes range at the Atlantic coast of Fennoscandia is traditionally assumed isostatically supported by variation in crustal density and thickness. Here we demonstrate, by our Silverroad seismic profile, that the constantly ~44 km thick crust instead is homogenous above the Moho, and Pn-velocity abruptly change from 7.

Development of SNP for Species Identification With Special Focus on the Cryptic Species Complex of .

The genus in the North Atlantic comprises of long lived deep-waters species that have been extensively fished upon, and many stocks are severely depleted across the Atlantic. This is particularly evident for the species . In recent papers, cryptic species have been indicated within this genus and molecular markers are therefore needed to provide identification for the species, including the cryptic species as a basis for advice regarding management and rebuilding of the stocks.

Population genomics and connectivity of Vazella pourtalesii sponge grounds of the northwest Atlantic with conservation implications of deep sea vulnerable marine ecosystems.

Sponges are key ecosystem engineers that shape, structure and enhance the biodiversity of marine benthic communities globally. Sponge aggregations and reefs are recognized as vulnerable marine ecosystems (or VMEs) due to their susceptibility to damage from bottom-contact fishing gears. Ensuring their long-term sustainability, preservation, and ecosystem functions requires the implementation of sound scientific conservation tools.

Transformative knowledge of polar polycyclic aromatic hydrocarbons via high-resolution mass spectrometry.

Polycyclic aromatic hydrocarbons (PAHs) are toxic contaminants with a widespread presence in diverse environmental contexts. Transformation processes of PAHs via degradation and biotransformation have parallels in humans, animals, plants, fungi, and bacteria. Mapping the transformation products of PAHs is therefore crucial for assessing their toxicological impact and developing effective monitoring strategies.

One-quarter of freshwater fauna threatened with extinction.

Freshwater ecosystems are highly biodiverse and important for livelihoods and economic development, but are under substantial stress. To date, comprehensive global assessments of extinction risk have not included any speciose groups primarily living in freshwaters. Consequently, data from predominantly terrestrial tetrapods are used to guide environmental policy and conservation prioritization, whereas recent proposals for target setting in freshwaters use abiotic factors.

Patchiness of plankton ecosystem structure due to nutrient mixing along the shelf edge in the North Sea.

Mid-water column turbulence has been shown to cause elevated vertical nutrient flux at the shelf edge in the northeastern North Sea. Here, we demonstrate that phytoplankton communities in this region tend to be dominated by larger cells (estimated from percentage of chlorophyll captured on a 10 μm filter) than beyond the shelf edge. F/F (PSII electron transport capacity) corrected for photoinhibition in the surface layer correlated in this study with the percentage of chlorophyll captured on a 10 µm filter (assumed to be large cells), suggesting that the phytoplankton community was responding to increased nutrients in the euphotic zone by increasing photosynthetic efficiency and altering community composition.