Kit M. Kovacs

Norwegian Polar Institute · Scientific Research Department

Climate change is impacting marine ecosystems throughout the circumpolar Arctic, altering seasonal habitats and the food bases for fishes, seabirds, and marine mammals. Arctic and Subarctic regions provide resources for resident species and for species that migrate to the north from more southerly regions. Changes in northerly latitudes thus impact...

Throughout the Arctic, ice‐affiliated marine mammals constitute local subsistence resources but detrimental effects of declines in their sea ice habitats create a need for harvest sustainability assessments in light of climate change. At the same time, empirical data required for thorough population analysis of these species are often sparse at bes...

Global warming is occurring at an accelerated rate in the Arctic compared to other parts of the planet with sea-ice declines being among the most striking manifestations of Arctic climate-related changes. Impacts of ongoing Arctic environmental change have been documented for biota throughout marine ecosystems from protists to top predators. Ice-de...

The Arctic is experiencing rapid reductions in sea ice, affecting all ice-dependant species. In the present study we examine interannual seasonal movements and habitat use in relation to sea ice coverage for one of the Arctic endemic marine mammals. We tagged 40 male walruses (Odobenus rosmarus) in the Svalbard Archipelago with custom-designed tusk...

How animals navigate during long-distance migration remains a mystery. Many theories have been proposed ¹ (Keeton, 1979), with the Earth’s magnetic field emerging as a clear potential source of orientational information for navigational decision-making across diverse taxa ² (Putman, 2022). Yet, the mechanics involved in magnetic navigation remain u...

Regular counts of walruses (Odobenus rosmarus) across their pan‐Arctic range are necessary to determine accurate population trends and in turn understand how current rapid changes in their habitat, such as sea ice loss, are impacting them. However, surveying a region as vast and remote as the Arctic with vessels or aircraft is a formidable logistic...

The bowhead whale, an Arctic endemic, was heavily overexploited during commercial whaling between the 16th-20th centuries. Current climate warming, with Arctic amplification of average global temperatures, poses a new threat to the species. Assessing the vulnerability of bowhead whales to near-future predictions of climate change remains challengin...

Despite the well-documented, broad global distribution of sperm whales ( Physeter macrocephalus ), their distributional patterns remain poorly known in Arctic regions, where year-round monitoring is challenging. Adult male sperm whales are known to migrate seasonally between nutrient-rich high latitude waters and low latitude breeding grounds. Howe...

The Arctic is a global warming ‘hot‐spot’ that is experiencing rapid increases in air and ocean temperatures and concomitant decreases in sea ice cover. These environmental changes are having major consequences on Arctic ecosystems. All Arctic endemic marine mammals are highly dependent on ice‐associated ecosystems for at least part of their life c...

Knowledge of genetic diversity and structure is essential for developing conservation strategies for endangered species. Blue whales were hunted to near extinction in the mid-twentieth century. Not-withstanding almost 380,000 animals killed globally, much remains unknown about their population structure and migration patterns. Herein, we use whole...

The Svalbard Archipelago, Norway, is warming rapidly, resulting in environmental change that is likely already affecting the underwater soundscape, a critical habitat feature for marine mammals. Baseline information about current sound levels is needed to monitor future changes. Fixed-location recorders were used in this study to characterize the s...

Studies on host–parasite systems that have experienced distributional shifts, range fragmentation, and population declines in the past can provide information regarding how parasite community richness and genetic diversity will change as a result of anthropogenic environmental changes in the future. Here, we studied how sequential postglacial colon...

The Earth's polar regions are low rates of inter‐ and intraspecific diversification. An extreme mammalian example is the Arctic ringed seal ( Pusa hispida hispida ), which is assumed to be panmictic across its circumpolar Arctic range. Yet, local Inuit communities in Greenland and Canada recognize several regional variants; a finding supported by s...

During summer, native anadromous Arctic char (Salvelinus alpinus) and the alien species pink salmon (Oncorhynchus gorbuscha) now coexist in marine environments in Svalbard, following the introduction of the latter in the Barents Region. To investigate potential dietary competition between these two salmonid species, stomach contents from Arctic cha...

The impacts of climate change on the health of marine mammals are increasingly being recognised. Given the rapid rate of environmental change in the Arctic, the potential ramifications on the health of marine mammals in this region are a particular concern. There are eleven endemic Arctic marine mammal species (AMMs) comprising three cetaceans, sev...

Herein we describe mating behaviour observed in a group of 20 white whales in Svalbard, Norway. A single female was the centre of attention during the 45-minute encounter, which was observed, photographed and videotaped at an ice edge in Storfjorden in June 2022. Several males surrounded the female and vigorously herded her from all sides. The fema...

The Svalbard white whale (Delphinapterus leucas) population is one of the smallest in the world, making it particularly vulnerable to challenges such as climate change and pathogens. In this study, serum samples from live captured (2001–2016) white whales from this region were investigated for influenza A virus (IAV) antibodies (Abs) (n = 27) and R...

To understand the exposure and potential sources of emerging brominated flame retardants (EBFR) and organophosphate esters (OPEs) in marine wildlife from the Norwegian Arctic, we investigated concentrations of EBFRs in 157 tissue samples from nine species of marine vertebrates and OPEs in 34 samples from three whale species. The samples, collected...

Despite the exclusion of the Southern Ocean from assessments of progress towards achieving the Convention on Biological Diversity (CBD) Strategic Plan, the Commission for the Conservation of Antarctic Marine Living Resources (CCAMLR) has taken on the mantle of progressing efforts to achieve it. Within the CBD, Aichi Target 11 represents an agreed c...

The main objective of the Working Group on the Integrated Assessments of the Barents Sea (WGIBAR) is to perform an integrated assessment of the Barents Sea ecosystem taking into account climate change and anthropogenic impacts, and to provide ecosystem information to ICES working groups and various users (managers, stakeholders and others). To achi...

Ocean warming is causing shifts in the distributions of marine species, but the location of suitable habitats in the future is unknown, especially in remote regions such as the Arctic. Using satellite tracking data from a 28-year-long period, covering all three endemic Arctic cetaceans (227 individuals) in the Atlantic sector of the Arctic, togethe...

In this study, we assess prey consumption by the marine mammal community in the northeast Atlantic [including 21 taxa, across three regions: (I) the Icelandic shelf, Denmark Strait, and Iceland Sea (ICE); (II) the Greenland and Norwegian Seas (GN); and (III) the Barents Sea (BS)], and compare mammal requirements with removals by fisheries. To deter...

Aim Identify hotspots and areas of high species richness for Arctic marine mammals. Location Circumpolar Arctic. Methods A total of 2115 biologging devices were deployed on marine mammals from 13 species in the Arctic from 2005 to 2019. Getis‐Ord Gi* hotspots were calculated based on the number of individuals in grid cells for each species and fo...

The East Greenland-Svalbard-Barents Sea (EGSB) bowhead whale stock (Balaena mysticetus) was hunted to near extinction and remains Endangered on the International Union of Conservation of Nature Red List. The intense, temporally extensive hunting pressure may have left the population vulnerable to other perturbations, such as environmental change. H...

Species with similar ecological requirements that overlap in range tend to segregate their niches to minimize competition for resources. However, the niche segregation possibilities for centrally foraging predators that breed on isolated Subantarctic islands may be reduced by spatial constraints and limitations in the availability of alternative pr...

The Arctic is warming rapidly, with concomitant sea ice losses and ecosystem changes. The animals most vulnerable to Arctic food web changes are long-lived and slow-growing such as marine mammals, which may not be able to adapt rapidly enough to respond to changes in their resource bases. To determine the current extent and sources of these resourc...

Global warming is affecting the population dynamics and trophic interactions across a wide range of ecosystems and habitats. Translating these real-time effects into their long-term consequences remains a challenge. The rapid and extreme warming period that occurred after the Last Glacial Maximum (LGM) during the Pleistocene–Holocene transition (7–...

This study uses cetacean sighting data, acquired via a citizen science programme, to update distributions and spatial trends of whales and dolphins in waters around the Svalbard Archipelago during the period 2005–2019. Distributions, based on kernel density estimates, from an early period (2005–2019) and a recent period (2015–19) were compared to i...

The harbour seal (Phoca vitulina) is the most widely distributed pinniped, occupying a wide variety of habitats and climatic zones across the Northern Hemisphere. Intriguingly, the harbour seal is also one of the most philopatric seals, raising questions as to how it colonised virtually the whole of the Northern Hemisphere. To shed light on the ori...

Understanding climate change impacts on top predators is fundamental to marine biodiversity conservation, due to their increasingly threatened populations and their importance in marine ecosystems. We conducted a systematic review of the effects of climate change (prolonged, directional change) and climate variability on seabirds and marine mammals...

Marine animals equipped with biological and physical electronic sensors have produced long-term data streams on key marine environmental variables, hydrography, animal behavior and ecology. These data are an essential component of the Global Ocean Observing System (GOOS). The Animal Borne Ocean Sensors (AniBOS) network aims to coordinate the long-t...

Climate change is impacting ice-affiliated marine mammal habitats throughout the Arctic, with sea ice declines reducing traditional haul-out and breeding habitats, putting a premium on alternative useable areas. In the Arctic, ice forms early in the season and is retained late into the spring in coastal lagoons, but little information is available...

The ringed seal is a small phocid seal that has a northern circumpolar distribution. It has long been recognized that body size is variable in ringed seals, and it has been suggested that ecotypes that differ in size exist. This study explores patterns of body size (length and girth) and age-at-maturity across most of the Arctic subspecies’ range u...

Sea-ice declines in the European Arctic have led to substantial changes in marine food webs. To better understand the biological implications of these changes, we quantified the contributions of ice-associated and pelagic carbon sources to the diets of Arctic harp and ringed seals using compound-specific stable isotope ratios of fatty acids in spec...

Ice is one of the most important drivers of population dynamics in polar organisms, influencing the locations, sizes, and connectivity of populations. Antarctic fur seals, Arctocephalus gazella, are particularly interesting in this regard, as they are concomitantly reliant on both ice-associated prey and ice-free coastal breeding areas. We reconstr...

Background: Health assessment of seals in captivity include haematology and serum biochemistry measurements. Because such parameters differ between species, it is crucial to have species-specific reference values for the interpretation of clinical samples. Furthermore, differences in nutrition and environment, life cycles as well as seasonal/annua...

Northern Hemisphere blue and fin whales are regular summer migrants to Arctic waters. Given the profound changes the Arctic is currently undergoing due to global warming, changes in habitat use and distribution of these migratory species are predicted. In this study, three passive acoustic recorders were used to investigate the spatial and temporal...

The Norwegian Polar Institute initiated a research programme on white whales in 1995 to gather biological information relevant for the species’ management; the results of which are reviewed herein. Satellite tracking from two periods (1995–2001 and 2013–16), between which sea ice diminished markedly, showed that the whales in waters off the archipe...

This study investigated concentrations of phthalates (diesters of phthalic acids) in blubber/adipose tissue of blue whales (Balaenoptera musculus), fin whales (Balaenoptera physalus), bowhead whales (Balaena mysticetus) and polar bears (Ursus maritimus) sampled in the Svalbard Archipelago (extending westward in the case of bowhead whales). Addition...

Male bearded seals ( Erignathus barbatus ) use vocal displays to attract females and to compete with other males during the mating season. This makes it possible to monitor breeding populations of this species using passive acoustic monitoring (PAM). This study analysed year-round acoustic data records from AURAL instruments in Svalbard (Norway) to...

This document provides an update on the status of marine mammals in the circumpolar Arctic from 2015– 2020

Ringed seals, which are small phocid seals, range across the circumpolar Arctic, and have evolved in close association with sea ice and depend on it for all aspects of their life history. This research study compares age structure, reproductive parameters, body size and condition during three time periods—1981–82 (n = 277), 2002–04 (n = 272) and 20...

Knowledge of genetic diversity and structure is essential for developing conservation strategies for endangered species. The advances in museum genomics can assist in better understanding the effects of over-hunting on the genome by comparing historical to present-day samples. Blue whales were hunted to the point of near extinction in the mid-twent...

Several Arctic marine mammal species are predicted to be negatively impacted by rapid sea ice loss associated with ongoing ocean warming. However, consequences for Arctic whales remain uncertain. To investigate how Arctic whales responded to past climatic fluctuations, we analyzed 206 mitochondrial genomes from beluga whales (Delphinapterus leucas)...

The impact of remotely piloted aircraft systems (RPAS) on marine mammals remains poorly documented despite their increasing use. In the high-Arctic Archipelago of Svalbard, where marine mammals face increasing pressure from climate change and expanding tourism, the use of RPAS remains largely unregulated. In this study we assessed the impacts of RP...

Environmental change and increasing levels of human activity are threats to marine mammals in the Arctic. Identifying marine mammal hotspots and areas of high species richness are essential to help guide management and conservation efforts. Herein, space use based on biotelemetric tracking devices deployed on 13 species (ringed seal Pusa hispida ,...

This study presents comprehensive mapping of the current distribution of pinnipeds and polar bears (Ursus maritimus) around Svalbard based on a regional marine mammal sightings programme and explores time-trends (2005–2018). Walruses (Odobenus rosmarus) were observed with high frequency and in high numbers around previously identified haul-out site...

Coastal waters are among the most productive regions in the Arctic (Leu et al. 2015; Smola et al. 2017; Ardyna et al. 2020). In these areas, a strong coupling exists between the sea and the land, and the shallow depths create a tight pelagic-benthic coupling (McGovern et al. 2020). These regions are also critical breeding and foraging grounds for m...

The fishery for Antarctic krill is currently managed using a precautionary, ecosystem-based approach to limiting catch, with performance indices from a long-term monitoring program focused on several krill-dependent predators that are used to track ecosystem health. Concerns over increased fishing in concentrated areas and ongoing efforts to establ...

insight into animal movements is essential for understanding habitat use by individuals as well as population processes and species life-history strategies. In this study, we instrumented 25 fin whales with ARGoS satellite-transmitters in Svalbard, norway, to study their movement patterns and behaviour (Area Restricted Search (ARS), transiting or u...

Full mitochondrial genomes were assembled for 12 recently sampled animals from the Svalbard bowhead whale (Balaena mysticetus) stock via high-throughput sequencing data, facilitating analysis of the demographic history of the population for the first time. The Svalbard population has retained noticeable amounts of mitochondrial genome diversity des...

Full mitochondrial genomes were assembled for 12 recently sampled animals from the Svalbard bowhead whale (Balaena mysticetus) stock via high-throughput sequencing data, facilitating analysis of the demographic history of the population for the first time. The Svalbard population has retained noticeable amounts of mitochondrial genome diversity des...

The monodontids—narwhals, Monodon monoceros, and belugas, Delphinapterus leucas—are found in much of the Arctic and in some subarctic areas. They are hunted by indigenous subsistence users. In the past, some populations were substantially reduced by commercial hunting and culling; more recently, some populations have declined due to uncontrolled su...