The Arctic is experiencing substantial warming with possibly large consequences for global climate when its large soil carbon stocks are mobilized. Yet the functioning of permafrost peatlands, which contain considerable amounts of carbon, is still not fully understood. Palaeoecological studies may contribute to unravelling this functioning but require actuo-ecological calibration of the environmental

The rare occurrence of redfish (genus Sebastes) in the White Sea encouraged Rolskii et al. (Polar Biol 43:385–389, 2020) to investigate the species identity of two animals captured near the Sredniy Island at 40 m depth. They reported that their morphological description proved unreliable and that genetic evidence “clearly demonstrated” these redfish belong to S. norvegicus. This was inferred using

Geothermal energy provides an important resource in Antarctic marine ecosystems, exemplified by the recent discovery of large-sized chemosymbiotic vesicomyid bivalves (subfamily Pliocardiinae) in the Southern Ocean. These clams, which we identified as Archivesica s.l. puertodeseadoi, have been reported as dead shells in areas previously covered by Larsen A and B ice shelves (eastern Antarctic Peninsula)

Frequent sampling of zooplankton is essential to understand their annual dynamics. However, in polar and subpolar ecosystems, such sampling is rare. This study comparatively analysed, for the first time, the annual mesozooplankton succession in the northwest nearshore and external zones of Ushuaia Bay in the sub-Antarctic Beagle Channel by monthly sampling over two years. The nearshore zone, with shallow

We studied positive associations among seabirds and marine mammals at South Georgia on research cruises during the Austral winters of 1985, 1991 and 1993 and found statistically significant differences. We collected data on abundance and distribution, providing a critical reference for sub-Antarctic conservation in anticipation of future environmental changes. We found significant changes in the abundance

Recently, Shum and Pampoulie (submitted) commented on our paper (Rolskii et al. 2020), which provided the first genetic confirmation of golden redfish Sebastes norvegicus in the White Sea. They argued that the White Sea redfish rather belong to a S. norvegicus × S. mentella hybrid. The objective of this reply is to respond to their criticisms.

Marine invertebrates can display several reproductive strategies, from external reproduction to parental care. Internal brooding is particularly relevant in harsh conditions, like Antarctic/sub-Antarctic waters and deep-sea, since it maximizes the survival of the young. Actinostola crassicornis is an abundant and widely distributed sea anemone from the southwestern Atlantic Ocean. It can be found all

Snow in Antarctica is a vast terrestrial ecosystem and plays a key role that has likely been underestimated. Algae are the key primary producers on the coloured snow surface, and they support a microbial community that includes bacteria, fungi and/or invertebrates. We analysed microbial communities that co-exist in green and red snow samples from the Fildes Peninsula by Illumina sequencing, Antarctica

The sponge diversity of the eastern Canadian Arctic remains largely unknown. Sponges of the three marine ecoregions which make up the eastern Canadian Arctic and sub-Arctic are described from collections using remote operated vehicle (ROV), box core, and Agassiz trawl. In total, 161 sponges were collected between 2015 and 2017, and 60 different species were identified. ROV surveys covered a range of

Bearded seals (Erignathus barbatus) are abundant in the Pacific Arctic and are an important subsistence resource for many Alaska Native communities. The Pacific Arctic is warming rapidly with substantial consequences predicted for ice-associated marine mammals, such as the bearded seal, which led to its 2012 listing as Threatened under the U.S. Endangered Species Act. We provide the most comprehensive

Cucumariidae (Echinodermata: Holothuroidea) is a family of sea cucumbers known for displaying different reproductive strategies, including brooding and hermaphroditism. These reproductive strategies of marine invertebrates are a key feature, since it is strongly related to evolutionary and ecological aspects. According to the place in which offsprings are grown, brooding can be classified in six groups

Species distribution models (SDMs) are increasingly used in ecological and biogeographic studies by Antarctic biologists, including for conservation and management purposes. During the modelling process, model calibration is a critical step to ensure model reliability and robustness, especially in the case of SDMs, for which the number of selected environmental descriptors and their collinearity is

The Magellanic Penguin Spheniscus magellanicus is one of the main seabird predators in the western South Atlantic. This species presents an opportunist feeding behaviour and its diet, as well as its parasite fauna, varies geographically depending on available prey and intermediate hosts. Despite thousands of Magellanic Penguins being found dead every year in southern Brazil, little attention has been

Mussel beds are common in many intertidal and subtidal habitats, including sub-Arctic and Arctic regions. Despite their ecological importance, little is known about the demographic processes governing the development of mussel beds and particularly about the synchronization of these processes at different spatial scales. The development of a relatively compact, narrow littoral mussel bed of Mytilus

Capelin (Mallotus villosus), a sub-Arctic forage fish, has become abundant in the Canadian Arctic in recent decades, with consistent spawning documented; however, the trophic role of capelin in these systems is unknown. We investigated the diets of small, immature (70–129 mm), medium, mature (130–174 mm), and large, mature (175–219 mm) capelin in Pangnirtung Fjord, Nunavut during and prior to spawning

Habitat loss and climate change are major processes affecting biodiversity, especially in the Arctic which is experiencing rapid sea ice decline. Loss of sea ice habitat for ice-dependent species such as polar bears (Ursus maritimus) has been associated with declines in body condition, reproductive output, survival, and abundance. Monitoring habitat use can therefore provide insights into population

Nuclear DNA content of marine macroalgae is known for only about a 3% of the globally known taxa, and so far, the only available data concerning marine Antarctic macroalgae refer to the Phaeophyceae Ascoseira mirabilis and Desmarestia antarctica. As these data can be useful for species delimitation when combined with other taxonomical information, we aimed to expand the available number of measurements

In the absence of any prior comprehensive analysis, I evaluate divergence along the biotope axis in the habitat stage of the evolutionary radiation of Antarctic cryonotothenioids. I utilize the available percentage buoyancy (%B) measurements as habitat proxies for recognition of the pelagic, semipelagic, demersal, and benthic biotopes that include, respectively, 5%, 10%, 73%, and 12% of the 59 species

Marine microbial communities undergo drastic changes during the seasonal cycle in high latitude seas. Despite the dominance of microbial biomass in the oceans, comprehensive studies on the seasonal changes of microbial plankton during the complete winter period are lacking. To study the seasonal variation in abundance of the microbial community, water samples were collected weekly in the Northern Baltic

Colobanthus quitensis (Kunth) Bartl. and Deschampsia antarctica Desv., the only two native flowering plants in the Antarctica, are interesting study cases from the ecological, biogeographic, and evolutionary points of view. Here, we present the first genome size analysis focused in several populations from the Antarctic Peninsula and the surrounding islands for both species, with a broad sampling distributed

The sounds of Arctic marine fishes recorded in situ have been largely ignored in the literature, despite the successful application of passive acoustic monitoring (PAM) for mapping the presence of fishes at lower latitudes. Polar cod, Boreogadus saida, is a known soniferous species that holds keystone status in the Arctic and for which PAM could be a useful tool for understanding their distributions-particularly

Reductions in sea ice and increases in air and seawater temperatures have been documented in the Arctic, making female Pacific walruses (Odobenus rosmarus divergens) vulnerable to changes in foraging, energy budgets, and reproductive fitness. The aim of the present study was to assess how walrus reproductive capacity has changed over a span of 35 years analyzing ovaries from three distinct time frames:

Gentoo penguins (Pygoscelis papua) have a widespread breeding distribution across the sub-Antarctic and Antarctic. Population trends vary across their range, with increases recorded in the Antarctic and Atlantic sectors of the Southern Ocean, while other sub-Antarctic populations are decreasing. Macquarie Island is the only breeding site for gentoo penguins in the Pacific sector of the Southern Ocean

Non-invasive tracking the on-shore occurrence of the atypically pigmented animals and determination of land residency duration of leucistic seals would help us find out more about the rotation of the migrating population. During seven austral summer seasons (2011–2018), by counting the animals every 10 days at the Cape Lions Rump shore, King George Island, South Shetlands, in the Antarctic Specially

This study provides the first documentation of polar bear (Ursus maritimus) maternity denning in snowdrifts around icebergs frozen into the fast ice or grounded on the seafloor. Based on six den observations in north and northeast Greenland during spring surveys in 2018 and 2019 (109 flight hours), together with observations of 20 adult females with 35 cubs of the year (COYs) in adjacent sea ice, we

Recent studies have shown that many species of apparently monogamous birds engage in extra-pair copulation (EPC). Penguins have intense shared parental care for their young, and thus have been considered monogamous. The present study aimed to assess the reproductive system of the gentoo penguin (Pygoscelis papua) on Elephant Island, Antarctica, by evaluating extra-pair paternity (EPP) and intraspecific

Global warming is causing Atlantification of water masses and concomitant changes in food webs in the Barents Sea region. To determine whether changes that have been documented at lower trophic levels are impacting the diet of ringed seals (Pusa hispida) gastrointestinal tracts (GITs) from 99 coastal-feeding ringed seals, collected in western Spitsbergen, Svalbard, were analysed via identification

The most plausible hypothesis for declining population trends of some marine top predators at the northern extent of their breeding ranges in the Southern Ocean is that it results from environmental change. Sub-Antarctic fur seals Arctocephalus tropicalis are opportunistic and pelagic foragers that feed on a variety of fish, cephalopods, and crustaceans throughout their range. Penguins are also targeted

Herbivores may have extensive top-down effects in open grazing ecosystems, generating vegetation changes by grazing and trampling. Trampling effects are understudied, but may be a major ecological factor. In cold alpine-Arctic ecosystems grazing and trampling by wild tundra reindeer (Rangifer tarandus) may be particularly important in lichen-dominated heaths. Dry lichen are crushed by trampling, and

Until recently, Antarctic animal species were thought to be safely isolated from human-associated infections. However, recent studies have shown that Antarctic penguins carry microorganisms, some of which are potential human pathogens. We investigated one rookery of Adelie penguins (Pygoscelis adeliae) and three rookeries of gentoo penguins (P. papua) for the presence of infectious diseases caused

Vocal-based monitoring is increasingly being used as a non-invasive method for identifying individuals within avian populations and is promising for the Siberian Crane, Leucogeranus leucogeranus. This is a poorly studied, long-lived, secretive and critically endangered bird species that breeds in the Arctic tundra of western and eastern regions of Siberia. We assessed between- and within-year stability

Penguins are important top consumers in marine food webs and are one of the most threatened bird families, especially by climate change and food web alterations by marine fisheries. Yet, long-term population trends are lacking or are uncertain for many populations. Seven species of penguins breeding at the French Southern Territories in the southern Indian Ocean on the Crozet, Kerguelen, Saint-Paul–Amsterdam

Ecological flexibility within animal populations can allow for variation in resource use and foraging decisions. We estimated brown bear (Ursus arctos) diet composition in Gates of the Arctic National Park and Preserve, Alaska from 2013 to 2015 to evaluate how variation in foraging behavior influences body condition and size. We used stable carbon (δ13C) and nitrogen (δ15N) isotope analyses of sectioned

Although most dives of emperor penguins (Aptenodytes forsteri) are less than 100 m, penguins from the Cape Washington colony regularly perform deep dives > 400 m. To evaluate the significance and location of these deep dives of birds on foraging trips from Cape Washington, we report the satellite tracks of three birds. We also review the frequency of deep dives in the 35 of 42 birds that performed

The Cape petrel (Daption capense) has circumpolar distribution and potential to be used as sentinels of trace elements levels in the Antarctic environment. This study measured trace elements in carcass feathers (n = 30) of this yet under-studied Procellariiform species, in King George Island, Antarctica. This non-invasive sampling method was useful for quantifying mercury (Hg), cadmium (Cd), selenium

Relationships between seabirds and cetaceans can vary from symbiotic to predatory. At high latitude seas in the Southern Hemisphere, giant petrels (Macronectes spp.) and male sperm whales (Physeter macrocephalus) are often solitary, but commercial longlining for Patagonian toothfish (Dissostichus eleginoides) provides consistent feeding opportunities that result in persistent aggregations of both.

Navaga, Eleginus nawaga, are an important component of some Arctic shelf seas, primarily in the Russian Arctic, yet very few publications on Navaga are available in the western scientific literature. Based on literary sources, a description of the distribution and biology of Navaga, Eleginus nawaga, in the White Sea, as well as a history of their fishery, are provided. Long-term changes in biological

Tardigrades are potentially dispersed by birds, but the extent of the interactions between birds and tardigrades is virtually unknown. We discovered nine tardigrades within feces of White-bellied Seedsnipe (Attagis malouinus) collected from high Andean tundra on Navarino Island, Chile. Eight of the tardigrade specimens began moving once rehydrated. Two specimens belonged to the genus Adropion (Hypsibiidae)

Ground-nesting birds, such as large gulls and skuas, are known to include a variety of items in their nests as pseudo-eggs, as well as to adopt the eggs of conspecifics or other species. Three hypotheses have been proposed to explain this phenomenon: incubation stimulus, mistaken food, and mistaken egg hypotheses. Of 657 Brown Skua Stercorarius antarcticus nests surveyed on Marion Island during the

This is an integrative study of a potential zoonotic digenean from the Magellanic Southwestern Atlantic coast. The life cycle of the gymnophallid Gymnophalloides nacellae Cremonte, Pina, Gilardoni, Rodrigues, Chai and Ituarte, 2013 (Digenea) at the type locality, Puerto Deseado (47° 45′ S, 65° 51′ W), Santa Cruz province, was elucidated. This digenean uses the upper subtidal clam Gaimardia trapesina

The continued decline in the small breeding population of southern elephant seals Mirounga leonina at Gough Island (40°19′S, 9°57′W) over a period of 46 years (1973–2019) signals the likely extirpation of the species at the northernmost extent of its breeding range in the Southern Ocean. The estimated number of births declined from a high (n = 38) in 1975 to a low (n = 2) in 2019, a 95% reduction at

Polar cod, Boreogadus saida, is an important part of Arctic and boreal marine ecosystems. Knowledge of polar cod population genetic structuring can provide insight into how the species may respond to environmental change, and allow for establishment of meaningful management units. To examine population genetic structure of B. saida, we analysed nine microsatellite DNA loci in 2269 fish collected at

Oxidative stress is considered the main physiological mechanism involved in short- and long-term life histories, operating through the progressive deterioration of tissues, with consequences in the reproductive performance, growth patterns, aging, and survival. Besides, the Antarctic Peninsula environmental change, registered in the last decades, makes essential the antioxidant status knowledge of

As in many Arctic regions, the fauna and biodiversity of Polar Ural lakes are not widely known. However, the fauna of these northern, relatively pristine lakes has recently become threatened due to industrial development in the Arctic. In this study, the zoobenthos of 13 relatively large lakes and 9 small ponds was studied during the summer (July and August) from 2003 to 2013. The aim was to conduct

Glaciers support diverse ecosystems that are largely comprised of microbial life. However, at larger, macroscopic scales, glacier moss balls (sometimes called “glacier mice”) can develop from impurities on ice surfaces and represent a relatively rare biological phenomenon. These ovoid-shaped conglomerations of dirt and moss are only found on some glacier surfaces and provide key habitats for invertebrate

Marine tardigrades in the Antarctic and sub-Antarctic regions are poorly understood. During the 59th Japan Antarctic Research Expedition, a sediment sample was collected from Lützow-Holm Bay, East Antarctica. The sediment sample yielded three species of marine tardigrades belonging to the family Styraconyxidae Kristensen & Renaud-Mornant, 1983: Angursa antarctica Villora-Moreno, 1998, Styraconyx cf

We surveyed the distribution and diversity of fungi present in moss fairy rings from the South Shetland Islands. In the different islands accessed, the mosses Bartramia patens, Brachythecium austrosalebrosum, Bryum pseudotriquetrum, Pohlia nutans, Polytrichastrum alpinum, Sanionia uncinata, Syntrichia magellanica, and Syntrichia saxicola were infected with fairy rings. Among them, B. patens, B. pseudotriquetrum

Baleen, a unique oral α-keratin, has flat cortical layers enclosing hollow horn tubules. Baleen grows continuously to replace erosive loss from feeding-related wear. This is essential for maintaining efficient filtration over a whale’s long life history. Baleen fragments are seen in stomach contents and feces. We focused on fin (Balaenoptera physalus) and bowhead whales (Balaena mysticetus), but examined

Recent discoveries of high levels of biological activity in the Arctic marine ecosystems during the polar night raise questions regarding the ecophysiology of the pelagic postlarval daubed shanny Leptoclinus maculatus. Of special interest is the composition of the lipid sac—a unique feature not found in other Arctic fishes. Analysis of the fatty acid content of major classes of lipids as membrane—total

Polar cod (Boreogadus saida) is a key forage fish in the Arctic marine ecosystem and provides an energetic link between lower and upper trophic levels. Despite its ecological importance, spatially explicit studies synthesizing polar cod distributions across research efforts have not previously been conducted in its Pacific range. We used spatial generalized additive models to map the distribution of

To understand the recovery process and population dynamics of species that were severely depleted, it is essential to monitor their population size and habitat changes throughout their distribution. The South American sea lion (SASL, Otaria flavescens) provides an opportunity to investigate the process of a reduction from sealing and the subsequent recovery in a marine mammal species. Its abundance

An understanding of host–parasite interactions represents an important, but often overlooked, axis for predicting how polar marine biodiversity may be impacted by continued environmental change over the next century. Here, we survey three species of crocodile icefish (Notothenioidei: Channichthyidae) collected from two island archipelagos in the southern Scotia Arc region for evidence of leech infestations

The large hairy armadillo (Chaetophractus villosus) was introduced to the Isla Grande of Tierra del Fuego almost 35 years ago. Previous studies described the armadillo’s distribution relative to heated oil pipelines. The present study updates this distribution, and evaluates associations with additional environmental variables to better explain the dispersion process and to propose areas for the control/eradication

Macroalgae such as kelp are important ecosystem engineers in the Polar Regions and potentially affected by freshening and ocean warming. The endemic Arctic kelp Laminaria solidungula might be particularly imperiled and become locally extinct from Arctic fjord systems in the future, since temperature increase is most pronounced in the Polar Regions. Additionally, increased temperatures cause glacier

In vertebrates, developmental conditions can affect not only fledging success but also the phenotype of the offspring, with potential long-term consequences on adult performance. However, surprisingly the potential impact of anthropogenic disturbance on developing chicks is rarely investigated, notably in Antarctic wildlife. In this study, we specifically investigated the effects of repeated nest visits

The soundscape is an important habitat feature for marine animals, and climate change may cause large changes to the Arctic marine soundscape through sea ice loss and increased anthropogenic activity. We examined the marine soundscape over eight months near Ulukhaktok, Northwest Territories, Canada, and assessed the relative contribution of the geophony (wind and wave sounds), biophony (marine mammal

Abstract The conservation status of wild walruses (Odobenus rosmarus) is influenced by rapid warming of the Arctic, loss of seasonal sea ice, and increasing pressures related to anthropogenic activities and associated noise. Few data are available regarding acoustic sensitivity in walruses, although the species is known to be vulnerable to human disturbance. Here, we provide new information to describe

Abstract Information on the ecology of invertebrate communities populating Macrocystis pyrifera forests in the Falkland Islands is scarce. Indeed, the factors influencing diversity, distribution and community structure have never been studied here. Benthic photoquadrats were collected along three permanent 20 m transects at three depth strata (shallow 5–10 m; middle 10–15 m; deep 15–20 m) off the coast

Abstract The distribution of Atlantic cod (Gadus morhua) in northern Norwegian waters is expanding eastward and northward in the Barents Sea and along western Svalbard. In the Arctic fjords of Svalbard, cod has become abundant, but little is known about the biology, origin, or residence patterns of these populations. To address this issue, we used laser ablation inductively coupled plasma mass spectrometry

Abstract Characterizing the condition of fish in dynamic seasonal environments requires an understanding of their energy allocation strategies. Both polar cod (Boreogadus saida) and saffron cod (Eleginus gracilis) are important mid-trophic fish in Alaska Arctic waters, and changes in their lipid allocation could have important implications for their overwintering survival as well as their energetic