The diving behaviours of marine predators are thought to be coupled with species demographics. Species that forage at or close to their physiological limits will be limited in their ability to respond to natural or anthropogenic induced changes in their environment. This is the case for the New Zealand sea lion (Phocarctos hookeri). A previous study from Enderby Island, Auckland Islands, the third

Though climate change is widely known to negatively affect the distribution and abundance of many species, few studies have focused on species that may benefit. Gentoo Penguin (Pygoscelis papua) populations have grown along the Western Antarctic Peninsula (WAP), a region accounting for ~ 30% of their global population. These trends of population growth in Gentoo Penguins are in stark contrast to those

Climatically extreme regions such as the polar deserts of the McMurdo Dry Valleys (78° S) in Continental Antarctica are key areas for a better understanding of changes in ecosystems. Therefore, it is particularly important to analyze and communicate current patterns of biodiversity in these sensitive areas, where precipitation mostly occurs in form of snow and liquid water is rare. Humidity provided

King penguins (Aptenodytes patagonicus) are a circumpolar sub-Antarctic species inhabiting most of the major sub-Antarctic island chains of the Southern Ocean, the Falkland Islands, and regions of Patagonia. Despite early suggestions to the contrary, there is no conclusive historical evidence of King penguin inhabitation of the Antarctic Peninsula or the South Shetland Islands until the past decade

Southern giant petrels (Macronectes giganteus) are opportunistic generalists whose feeding strategies include hunting, scavenging and fishing. While seals are important for southern giant petrels as a source of carrion, we documented that live seals also provide feeding opportunities for southern giant petrels. We tracked breeding southern giant petrels from Harmony Point, Antarctica, during incubation

Cyanobacterial mat communities are the main drivers of primary productivity in the McMurdo Dry Valleys, Antarctica. These microbial communities form laminar mats on desert pavement surfaces adjacent to glacial meltwater streams, ponds, and lakes. The low-density nature of these communities and their patchy distribution make assessments of distribution, biomass, and productivity challenging. We used

Biocrusts can be found in a wide array of habitats, where they provide important ecosystem services. These microbial associations are particularly important in High Arctic environments, where biocrust colonize the newly exposed barren soil after glacier retreat and significantly contribute to soil stabilization and nutrient cycling. Starting from incipient, structurally simple biolayers, they develop

The Arctic supports a diversity of breeding birds. Since the mid-twentieth century, anthropogenic-source climate change, industrial activity and harvest have impacted this ecosystem and the demographics of its breeding birds, highlighting the need to synthesise current knowledge. A scoping review was conducted to quantify recent population trends and identify impacts of anthropogenic activity on species’

Respiration is a crucial process that provides all living organisms with energy and metabolites for growth and cellular maintenance. The processes that control respiration in lichens remain poorly understood. We investigated the effects of short-term temperature changes on the respiration rate, as well as the relative contributions of the cytochrome and alternative pathways of thalli from four green-algal

As an annual ice-associated species, bowhead whales (Balaena mysticetus) are known to move northward in mid-to-late March and southward in early winter while following the annual cycle of sea ice decay and formation. We sought to determine when and where different demographic groups of Eastern Canada-West Greenland bowhead whales foraged throughout their range and what seasonal patterns occurred in

As ocean temperatures rise, sub-Arctic capelin (Mallotus villosus) and sand lance (Ammodytes spp.) have become increasingly abundant in regions of the eastern Canadian Arctic. These fish have a similar trophic role to the keystone polar cod (Boreogadus saida), potentially competing for food resources when co-occurring. To evaluate this, we calculated feeding niche breadth and overlap based on fatty

Despite cold adaptation, Antarctic fish show lower growth than expected from the van’t Hoff’s Q10 rule. Protein synthesis is one of the main energy-consuming processes, which is downregulated under energy deficiency. Considering the effect of temperature on growth performance, we tested if temperature-dependent cellular energy allocation to protein synthesis correlates with temperature-dependent whole-animal

Southernmost South America provides significant wintering habitats for migrant shorebirds, most of which breed in the High Arctic tundra. Helminth species parasitizing these migratory birds have been well studied in North America; however, in South America they are poorly known. As part of an ongoing research on the helminth fauna from Patagonian birds in Argentina, we report Notocotylus chionis and

Many seabird species in the North Atlantic region have shown considerable declines in their populations during recent decades. One such species is the Arctic tern (Sterna paradisaea), a small seabird which migrates farther than any other seabird each year and whose global population is thought to be in decline. We used banding data of chicks and adults, spanning five decades (1974–2017) from a tern

Sea ice algae, comprised mainly of diatoms, are the main primary producers in polar ecosystems, and they are generally distributed with the highest biomass at the bottom of ice. The taxonomy of ice algae has been traditionally investigated using light microscopy, but molecular techniques, including pigment analysis, have recently provided new insights into the diversity and physiology of ice algae

Pleistocene climate cycles greatly influenced the distributions of kelps in northern seas and gated trans-Arctic dispersals between the North (N) Pacific and N Atlantic oceans. Here, we used partial sequences of the mitochondrial DNA cytochrome oxidase I-5′ (COI) and plastid ribulose-1,5-bisphosphate carboxylase/oxygenase large subunit-3′ (rbcL) to resolve the phylogeography of the kelp Hedophyllum

Beluga whales (Delphinapterus leucas) occur broadly throughout the polar and subpolar regions of the Northern Hemisphere, and as a whole, the species is of low conservation concern. However, some populations, including Alaska’s Cook Inlet beluga whales (CIBW), are in decline for reasons that remain poorly understood. Currently, information on population-specific reproductive parameters of CIBW is non-existent

The flora of sub-Antarctic Marion Island forms part of the unique South Indian Ocean Biogeographic Province, and is under threat from climate change and invasive species. Current information on the flora is necessary to rapidly identify and manage future changes. We conducted a literature search on the taxonomy of indigenous vascular plant species on Marion Island and found nomenclatural changes following

Arctic marine ecosystems are undergoing rapid biogeographic responses to climate changes following the highest warming rates observed around the globe in recent decades. These drastic changes undoubtfully affect gene flow and genetic structure in the polar and subpolar regions. Here, we examine the genetic structure of the cold-water holozooplankton hyperiid Themisto libellula (Amphipoda: Hyperiidae)

The first non-coastal Sub-Antarctic Marine Protected Area (Namuncurá) in Argentina was created in 2013, at Burdwood Bank (MPAN-BB), an undersea plateau located about 200 km south from Malvinas/Falkland Islands, SW Atlantic Ocean. The main contribution of this work was to explore fish species composition and the structure of fish assemblages in three different zones of the MPAN-BB with different conservation

Environmental variability drives Adélie penguin (Pygoscelis adeliae) population dynamics through its effects on vital rates (e.g., survival, dispersal, or breeding success) resulted in penguin abundance changes with time delays. The lagged effects of environmental changes on penguin abundance are still not well defined. We divided the Ross Sea region into six areas to investigate the effects of environmental

Though leopard seals live and reproduce almost exclusively in fast ice and pack ice habitats surrounding the Antarctic Continent, they have been reported to range northward to South Georgia in the South Atlantic Ocean, South Africa, Patagonia, New Zealand and several islands in the South Atlantic, South Pacific, and southern Indian oceans. We summarize recent (2011 through 2018) sightings of leopard

Imagery and sighting data on bowhead whale (Balaena mysticetus) carcasses documented from 2009 to 2018 during aerial surveys in the eastern Chukchi and western Beaufort seas have provided evidence for killer whale (Orcinus orca) predation on bowhead whales of the Bering–Chukchi–Beaufort Seas stock. The Aerial Surveys of Arctic Marine Mammals (ASAMM) project provides information on distribution, behavior

There are very few long-term studies on Antarctic vegetation available, and very little is known of plant community changes over time in the Antarctic Peninsula area, an area itself subject to considerable change in recent decades. The vegetation of the South Bay area near the Spanish Station Juan Carlos I on Livingston island (South Shetland Islands) was extensively surveyed in the 1980s, and this

In times of accelerating climate change, species are challenged to respond to rapidly shifting environmental settings. Yet, faunal distribution and composition are still scarcely known for remote and little explored seas, where observations are limited in number and mostly refer to local scales. Here, we present the first comprehensive study on Eurasian-Arctic macrobenthos that aims to unravel the

The marine area of Northeast Greenland belongs to the largest national park in the world. Biodiversity assessments and tailored conservation measures often target specific physiographic or oceanographic features of an area for which detailed knowledge on their biological communities is incomplete. This study, therefore, characterizes epibenthic megafauna communities in a priori defined seabed habitats

Bearded seals (Erignathus barbatus) have a circumpolar Arctic distribution and are closely associated with unstable pack ice, spending nearly all of their lives in remote habitats. As a result, their biology and behavior remain largely unknown. With respect to sensory biology, bearded seals—like other marine mammals—rely on acoustic cues to support a range of vital behaviors. Acoustic monitoring from

The Magellan plunderfish Harpagifer bispinis is a small and benthic sub-Antarctic notothenioid commonly found in shallow waters of the Beagle Channel, whose biology is poorly known. Based on a seasonal sampling conducted throughout a year, we provide original data on some biological parameters, such as reproductive traits and age structure. The sampled population of Magellan plunderfish was sex balanced

In tundra ecosystems, snow cover protects plants from low temperatures in winter and buffers temperature fluctuations in spring. Climate change may lead to reduced snowfall and earlier snowmelt, potentially exposing plants to more frequent and more severe frosts in the future. Frost can cause cell damage and, in combination with high solar irradiance, reduce the photochemical yield of photosystem II

Ornithogenic soils in Antarctica provide a biological archive of the occupation history and trophic ecology of penguins and other marine species over geological timescales. Hard prey remains and predator tissues, which are well preserved in ornithogenic soils, can act as paleoecological proxies of past environmental conditions. Here we examine ornithogenic soils from an active colony of Pygoscelis

Efforts to study the effects of environmental change on early development of Antarctic fishes would benefit from the ability to control reproduction by in vitro fertilization. Here, we established a spectrophotometric method to determine spermatozoa concentration in the semen of the blackfin icefish Chaenocephalus aceratus and we evaluated the potential for short (refrigeration) and long-term (cryopreservation)

Burdwood Bank is a shallow seamount located south of the Malvinas (Falkland) Islands and east of Tierra del Fuego. In 2013, the area down to 200 m depth of this bank was declared the first open-sea (non-coastal) Marine Protected Area (MPA) in Argentina, and named “Namuncurá” (MPAN-BB). The present study aimed to evaluate the biodiversity of the isopods and cumaceans from the MPAN-BB. The studied material

Bone-eating worms of the genus Osedax (Annelida, Siboglinidae) form unique holobionts (functional entity comprising host and associated microbiota), highly adapted to inhabit bone tissue of marine vertebrates. These gutless worms have developed nutritional symbioses housing intracellular, horizontally acquired, heterotrophic bacteria hypothesised to harness nutrients from organic compounds, sequestered

The present study is a valuable contribution to the knowledge of feeding habits of Patagonian toothfish Dissostichus eleginoides in Southwestern Atlantic (53–55°S, 351 to 1073 m depth) near Burdwood Bank/Namuncurá marine-protected area, where diet has not been previously investigated. Based on stomach content analyses of 441 specimens ranging from 38 to 190 cm total length (TL), our study tested the

The plant-parasitic nematodes of Iceland are poorly understood. To address this, a study of the nematodes of the families Criconematidae and Hemicycliophoridae was performed in 2015. Soil samples were taken from underneath various host plants in different locations in Iceland. The identification was performed on the basis of the general morphology and subsequently confirmed by molecular markers (D2-D3

As Arctic seas rapidly change with increased ocean temperatures and decreased sea ice extent, traditional Arctic marine mammal distributions may be altered, and typically temperate marine mammal species may shift poleward. Extant and seasonal odontocete species on the continental shelves of the Bering and Chukchi Seas include killer whales (Orcinus orca), sperm whales (Physeter microcephalus), beluga

Annual ice retreat in the northern Bering and Chukchi seas, which has occurred earlier in the past decades resulting in longer ice-free seasons and warmer ocean temperatures, is producing a cascade of ecological effects, and may open Arctic waters to commercial fishing and oil exploration. Baseline knowledge of population structure of a species is critical to developing strategies for management and

There are important gaps to understand the composition of the fauna associated with macroalgae, such as, how distinct algal morphology and environmental features, like turbulence or circulation patterns, may affect the distribution of them. In this study, macroalgae and associated fauna samples were undertaken between 4 and 12-m depth at three sites within the Admiralty Bay, King George Island, during

In spite of the generally high interest to ecosystems of high latitudes, there is not a single mite species list for any Arctic coastal location yet. Mesostigmatic mites are diverse and abundant in invertebrate littoral communities, while in the sea wrack, they are a dominant mite group. We studied these mites in different coastal habitats in the forested tundra landscape in the vicinity of Murmansk

The Southern Ocean (SO), in spite of its major contribution to global primary productivity (PP), remains underexplored in this aspect. Light being the most limiting parameter affecting primary production, it is crucial to study the ambient light field to understand PP and associated processes. The current study makes a dual effort to present PP estimates as well as understand the bio-optical variability

There is limited information about the biology and seasonal distribution of bearded seals (Erignathus barbatus) in Greenland. The species is highly ice-associated and depends on sea ice for hauling out and giving birth, making it vulnerable to climate change. We investigated the seasonality and distribution of bearded seal vocalizations at seven different locations across southern Baffin Bay and Davis

Overwinter environmental conditions are a major driver of larval survival, recruitment, and reproductive pre-conditioning in Antarctic krill (Euphausia superba). Few winter studies exist from which to infer impacts of changing environmental conditions on the biology of krill. Here demographic and maturity patterns of krill during five winters are examined at an overwintering hotspot in the northern

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