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An Arctic predator-prey system in flux: climate change impacts on coastal space use by polar bears and ringed seals.

https://arctichealth.org/en/permalink/ahliterature281815
Source
J Anim Ecol. 2017 Apr 17;
Publication Type
Article
Date
Apr-17-2017
Author
Charmain D Hamilton
Kit M Kovacs
Rolf A Ims
Jon Aars
Christian Lydersen
Source
J Anim Ecol. 2017 Apr 17;
Date
Apr-17-2017
Language
English
Publication Type
Article
Abstract
1.Climate change is impacting different species at different rates, leading to alterations in biological interactions with ramifications for wider ecosystem functioning. Understanding these alterations can help improve predictive capacity and inform management efforts designed to mitigate against negative impacts. 2.We investigated how the movement and space use patterns of polar bears (Ursus maritimus) in coastal areas in Svalbard, Norway, have been altered by a sudden decline in sea ice that occurred in 2006. We also investigated whether the spatial overlap between polar bears and their traditionally most important prey, ringed seals (Pusa hispida), has been affected by the sea-ice decline, as polar bears are dependent on a sea-ice platform for hunting seals. 3.We attached biotelemetry devices to ringed seals (n=60, both sexes) and polar bears (n=67, all females) before (2002-2004) and after (2010-2013) a sudden decline in sea ice in Svalbard. We used linear mixed-effects models to evaluate the association of these species to environmental features and an approach based on Time Spent in Area to investigate changes in spatial overlap between the two species. 4.Following the sea-ice reduction, polar bears spent the same amount of time close to tidal glacier fronts in the spring but less time in these areas during the summer and autumn. However, ringed seals did not alter their association with glacier fronts during summer, leading to a major decrease in spatial overlap values between these species in Svalbard's coastal areas. Polar bears now move greater distances daily and spend more time close to ground-nesting bird colonies, where bear predation can have substantial local effects. 5.Our results indicate that sea-ice declines have impacted the degree of spatial overlap and hence the strength of the predator-prey relationship between polar bears and ringed seals, with consequences for the wider Arctic marine and terrestrial ecosystems. Shifts in ecological interactions are likely to become more widespread in many ecosystems as both predators and prey respond to changing environmental conditions induced by global warming, highlighting the importance of multi-species studies. This article is protected by copyright. All rights reserved.
PubMed ID
28415134 View in PubMed
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Aquatic behaviour of polar bears (Ursus maritimus) in an increasingly ice-free Arctic.

https://arctichealth.org/en/permalink/ahliterature292547
Source
Sci Rep. 2018 Jun 26; 8(1):9677
Publication Type
Journal Article
Date
Jun-26-2018
Author
Karen Lone
Kit M Kovacs
Christian Lydersen
Mike Fedak
Magnus Andersen
Philip Lovell
Jon Aars
Author Affiliation
Norwegian Polar Institute, Norwegian Polar Institute, Fram Centre, 9296, Tromsø, Norway. karen.lone@npolar.no.
Source
Sci Rep. 2018 Jun 26; 8(1):9677
Date
Jun-26-2018
Language
English
Publication Type
Journal Article
Abstract
Polar bears are ice-associated marine mammals that are known to swim and dive, yet their aquatic behaviour is poorly documented. Reductions in Arctic sea ice are clearly a major threat to this species, but understanding polar bears' potential behavioural plasticity with respect to the ongoing changes requires knowledge of their swimming and diving skills. This study quantified time spent in water by adult female polar bears (n?=?57) via deployment of various instruments bearing saltwater switches, and in some case pressure sensors (79 deployments, 64.8 bear-years of data). There were marked seasonal patterns in aquatic behaviour, with more time spent in the water during summer, when 75% of the polar bears swam daily (May-July). Females with cubs-of-the-year spent less time in the water than other females from den emergence (April) until mid-summer, consistent with small cubs being vulnerable to hypothermia and drowning. Some bears undertook notable long-distance-swims. Dive depths up to 13.9?m were recorded, with dives =5?m being common. The considerable swimming and diving capacities of polar bears might provide them with tools to exploit aquatic environments previously not utilized. This is likely to be increasingly important to the species' survival in an Arctic with little or no persistent sea ice.
Notes
Cites: Oecologia. 2008 Feb;155(1):193-204 PMID 17990001
Cites: J Anim Ecol. 2017 Sep;86(5):1054-1064 PMID 28415134
Cites: Am J Physiol. 1979 Jan;236(1):R67-74 PMID 434189
PubMed ID
29946080 View in PubMed
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Arctic marine mammal population status, sea ice habitat loss, and conservation recommendations for the 21st century.

https://arctichealth.org/en/permalink/ahliterature270034
Source
Conserv Biol. 2015 Jun;29(3):724-37
Publication Type
Article
Date
Jun-2015
Author
Kristin L Laidre
Harry Stern
Kit M Kovacs
Lloyd Lowry
Sue E Moore
Eric V Regehr
Steven H Ferguson
Øystein Wiig
Peter Boveng
Robyn P Angliss
Erik W Born
Dennis Litovka
Lori Quakenbush
Christian Lydersen
Dag Vongraven
Fernando Ugarte
Source
Conserv Biol. 2015 Jun;29(3):724-37
Date
Jun-2015
Language
English
Publication Type
Article
Keywords
Animals
Arctic Regions
Cetacea - physiology
Climate change
Conservation of Natural Resources
Ecosystem
Ice Cover
Pinnipedia - physiology
Population Density
Abstract
Arctic marine mammals (AMMs) are icons of climate change, largely because of their close association with sea ice. However, neither a circumpolar assessment of AMM status nor a standardized metric of sea ice habitat change is available. We summarized available data on abundance and trend for each AMM species and recognized subpopulation. We also examined species diversity, the extent of human use, and temporal trends in sea ice habitat for 12 regions of the Arctic by calculating the dates of spring sea ice retreat and fall sea ice advance from satellite data (1979-2013). Estimates of AMM abundance varied greatly in quality, and few studies were long enough for trend analysis. Of the AMM subpopulations, 78% (61 of 78) are legally harvested for subsistence purposes. Changes in sea ice phenology have been profound. In all regions except the Bering Sea, the duration of the summer (i.e., reduced ice) period increased by 5-10 weeks and by >20 weeks in the Barents Sea between 1979 and 2013. In light of generally poor data, the importance of human use, and forecasted environmental changes in the 21st century, we recommend the following for effective AMM conservation: maintain and improve comanagement by local, federal, and international partners; recognize spatial and temporal variability in AMM subpopulation response to climate change; implement monitoring programs with clear goals; mitigate cumulative impacts of increased human activity; and recognize the limits of current protected species legislation.
PubMed ID
25783745 View in PubMed
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Autumn movements of fin whales (Balaenoptera physalus) from Svalbard, Norway, revealed by satellite tracking.

https://arctichealth.org/en/permalink/ahliterature304490
Source
Sci Rep. 2020 10 12; 10(1):16966
Publication Type
Journal Article
Research Support, Non-U.S. Gov't
Date
10-12-2020
Author
Christian Lydersen
Jade Vacquié-Garcia
Mads Peter Heide-Jørgensen
Nils Øien
Christophe Guinet
Kit M Kovacs
Author Affiliation
Norwegian Polar Institute, Fram Centre, 9296, Tromsö, Norway. christian.lydersen@npolar.no.
Source
Sci Rep. 2020 10 12; 10(1):16966
Date
10-12-2020
Language
English
Publication Type
Journal Article
Research Support, Non-U.S. Gov't
Abstract
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 unknown) during boreal autumn/early winter. Ten of the whales stayed in the tagging area (most northerly location: 81.68°N) for their entire tracking periods (max 45 days). The other 15 whales moved in a south-westerly direction; the longest track ended off the coast of northern Africa (>?5000 km from the tagging location) after 96 days. The whales engaged in ARS behaviour intermittently throughout their southward migrations. During transit phases the whales moved quickly; one individual maintained an average horizontal speed of 9.3 km/h (travelling 223 km per day) for a period of a week. This study documents that: (1) some fin whales might remain at high latitudes during winter; (2) the whales that do migrate probably feed along the way; (3) they can maintain high transiting speed for long periods and; (4) one breeding area for this species is likely located in deep, warm water some 100 km west of Morocco.
PubMed ID
33046805 View in PubMed
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Circulating thyroid hormones and associated metabolites in white whales (Delphinapterus leucas) determined using isotope-dilution mass spectrometry.

https://arctichealth.org/en/permalink/ahliterature281089
Source
Environ Res. 2017 Mar 22;156:128-131
Publication Type
Article
Date
Mar-22-2017
Author
Martin Hansen
Gro D Villanger
Thea Bechshoft
Milton Levin
Heli Routti
Kit M Kovacs
Christian Lydersen
Source
Environ Res. 2017 Mar 22;156:128-131
Date
Mar-22-2017
Language
English
Publication Type
Article
Abstract
Blood was sampled from nine free-ranging white whales (beluga whale, Delphinapterus leucas) from Svalbard, Norway during the summers of 2013 and 2014. Total concentrations of eleven thyroid hormones and metabolites were measured in serum using a novel liquid chromatography tandem mass spectrometry analytical method. Measurements of these compounds in plasma gave the same results as in serum. The three hormones found in highest concentrations were 3,3',5-triiodothyronine (T3), 3,3',5'-triiodothyronine (rT3) and thyroxine (T4). Traces of associated metabolites were also found.
PubMed ID
28342348 View in PubMed
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Circumpolar phylogeography and demographic history of beluga whales reflect past climatic fluctuations.

https://arctichealth.org/en/permalink/ahliterature311324
Source
Mol Ecol. 2021 Apr 07; :
Publication Type
Journal Article
Date
Apr-07-2021
Author
Mikkel Skovrind
Marie Louis
Michael V Westbury
Cristina Garilao
Kristin Kaschner
José Alfredo Samaniego Castruita
Shyam Gopalakrishnan
Steen Wilhelm Knudsen
James S Haile
Love Dalén
Ilya G Meshchersky
Olga V Shpak
Dmitry M Glazov
Viatcheslav V Rozhnov
Dennis I Litovka
Vera V Krasnova
Anton D Chernetsky
V M Bel'kovich
Christian Lydersen
Kit M Kovacs
Mads Peter Heide-Jørgensen
Lianne Postma
Steven H Ferguson
Eline D Lorenzen
Author Affiliation
GLOBE Institute, University of Copenhagen, Denmark.
Source
Mol Ecol. 2021 Apr 07; :
Date
Apr-07-2021
Language
English
Publication Type
Journal Article
Abstract
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) sampled across their circumpolar range, and four nuclear genomes, covering both the Atlantic and the Pacific Arctic region. We find four well-differentiated mitochondrial lineages, which were established before the onset of the last glacial expansion ~110 thousand years ago. Our findings suggest these lineages diverged in allopatry, reflecting isolation of populations during glacial periods, when the Arctic sea-shelf was covered by multi-year sea ice. Subsequent population expansion and secondary contact between the Atlantic and Pacific Oceans has shaped the current geographic distribution of lineages, and likely facilitated mitochondrial introgression. Our demographic reconstructions based on both mitochondrial and nuclear genomes show markedly lower population sizes during the Last Glacial Maximum (LGM) compared to the preceding Eemian and current Holocene interglacial periods. Habitat modelling similarly reveals less suitable habitat during the LGM (glacial) than at present (interglacial). Together, our findings suggest an association between climate, population size and available habitat in belugas. Forecasts for year 2100 show that beluga habitat will decrease and shift northwards as oceans continue to warm, putatively leading to population declines in some beluga populations. Finally, we identify vulnerable populations which, if extirpated as a consequence of ocean warming, would lead to a substantial decline of species-wide haplotype diversity.
PubMed ID
33825233 View in PubMed
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Climate change impacts on wildlife in a High Arctic archipelago - Svalbard, Norway.

https://arctichealth.org/en/permalink/ahliterature273296
Source
Glob Chang Biol. 2016 Jun 2;
Publication Type
Article
Date
Jun-2-2016
Author
Sébastien Descamps
Jon Aars
Eva Fuglei
Kit M Kovacs
Christian Lydersen
Olga Pavlova
Åshild Ø Pedersen
Virve Ravolainen
Hallvard Strøm
Source
Glob Chang Biol. 2016 Jun 2;
Date
Jun-2-2016
Language
English
Publication Type
Article
Abstract
The Arctic is warming more rapidly than other region on the planet, and the northern Barents Sea, including the Svalbard Archipelago, is experiencing the fastest temperature increases within the circumpolar Arctic, along with the highest rate of sea ice loss. These physical changes are affecting a broad array of resident Arctic organisms as well as some migrants that occupy the region seasonally. Herein, evidence of climate change impacts on terrestrial and marine wildlife in Svalbard is reviewed, with a focus on bird and mammal species. In the terrestrial ecosystem, increased winter air temperatures and concomitant increases in the frequency of "rain-on-snow" events are one of the most important facets of climate change with respect to impacts on flora and fauna. Winter rain creates ice that blocks access to food for herbivores and synchronizes the population dynamics of the herbivore-predator guild. In the marine ecosystem, increases in sea temperature and reductions in sea ice are influencing the entire food web. These changes are affecting the foraging and breeding ecology of most marine birds and mammals, and are associated with an increase in abundance of several temperate fish, seabird and marine mammal species. Our review indicates that, even though a few species are benefiting from a warming climate, most Arctic endemic species in Svalbard are experiencing negative consequences induced by the warming environment. Our review emphasizes the tight relationships between the marine and terrestrial ecosystems in this High Arctic archipelago. Detecting changes in trophic relationships within and between these ecosystems requires long-term (multi-decadal) demographic, population- and ecosystem-based monitoring, the results of which are necessary to set appropriate conservation priorities in relation to climate warming. This article is protected by copyright. All rights reserved.
PubMed ID
27250039 View in PubMed
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Comparative Brain Morphology of the Greenland and Pacific Sleeper Sharks and its Functional Implications.

https://arctichealth.org/en/permalink/ahliterature301704
Source
Sci Rep. 2019 Jul 11; 9(1):10022
Publication Type
Journal Article
Date
Jul-11-2019
Author
Kara E Yopak
Bailey C McMeans
Christopher G Mull
Kirk W Feindel
Kit M Kovacs
Christian Lydersen
Aaron T Fisk
Shaun P Collin
Author Affiliation
Department of Biology and Marine Biology and the UNCW Center for Marine Science, University of North Carolina Wilmington, Wilmington, NC, 28403, United States. yopakk@uncw.edu.
Source
Sci Rep. 2019 Jul 11; 9(1):10022
Date
Jul-11-2019
Language
English
Publication Type
Journal Article
Abstract
In cartilaginous fishes, variability in the size of the brain and its major regions is often associated with primary habitat and/or specific behavior patterns, which may allow for predictions on the relative importance of different sensory modalities. The Greenland (Somniosus microcephalus) and Pacific sleeper (S. pacificus) sharks are the only non-lamnid shark species found in the Arctic and are among the longest living vertebrates ever described. Despite a presumed visual impairment caused by the regular presence of parasitic ocular lesions, coupled with the fact that locomotory muscle power is often depressed at cold temperatures, these sharks remain capable of capturing active prey, including pinnipeds. Using magnetic resonance imaging (MRI), brain organization of S. microcephalus and S. pacificus was assessed in the context of up to 117 other cartilaginous fish species, using phylogenetic comparative techniques. Notably, the region of the brain responsible for motor control (cerebellum) is small and lacking foliation, a characteristic not yet described for any other large-bodied (>3?m) shark. Further, the development of the optic tectum is relatively reduced, while olfactory brain regions are among the largest of any shark species described to date, suggestive of an olfactory-mediated rather than a visually-mediated lifestyle.
PubMed ID
31296954 View in PubMed
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Concentrations and endocrine disruptive potential of phthalates in marine mammals from the Norwegian Arctic.

https://arctichealth.org/en/permalink/ahliterature311925
Source
Environ Int. 2021 07; 152:106458
Publication Type
Journal Article
Research Support, Non-U.S. Gov't
Date
07-2021
Author
Heli Routti
Mikael Harju
Katharina Lühmann
Jon Aars
Amalie Ask
Anders Goksøyr
Kit M Kovacs
Christian Lydersen
Author Affiliation
Norwegian Polar Institute, Fram Centre, N-9296 Tromsø, Norway. Electronic address: heli.routti@npolar.no.
Source
Environ Int. 2021 07; 152:106458
Date
07-2021
Language
English
Publication Type
Journal Article
Research Support, Non-U.S. Gov't
Keywords
Animals
Arctic Regions
Fin Whale
Phthalic Acids - toxicity
Svalbard
Abstract
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). Additionally, total concentrations (free and conjugated forms) of eight phthalate monoester metabolites were analysed in plasma of polar bears. Bis(2-ethylhexyl) phthalate (DEHP) was the only phthalate quantified among the 12 phthalates investigated. This compound was present in 6/7 fin whale samples, 4/7 blue whale samples, 2/5 bowhead whale samples and 1/12 polar bear samples. DEHP concentrations ranged from
PubMed ID
33677245 View in PubMed
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Concentrations and endocrine disruptive potential of phthalates in marine mammals from the Norwegian Arctic.

https://arctichealth.org/en/permalink/ahliterature306375
Source
Environ Int. 2021 Mar 04; 152:106458
Publication Type
Journal Article
Date
Mar-04-2021
Author
Heli Routti
Mikael Harju
Katharina Lühmann
Jon Aars
Amalie Ask
Anders Goksøyr
Kit M Kovacs
Christian Lydersen
Author Affiliation
Norwegian Polar Institute, Fram Centre, N-9296 Tromsø, Norway. Electronic address: heli.routti@npolar.no.
Source
Environ Int. 2021 Mar 04; 152:106458
Date
Mar-04-2021
Language
English
Publication Type
Journal Article
Abstract
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). Additionally, total concentrations (free and conjugated forms) of eight phthalate monoester metabolites were analysed in plasma of polar bears. Bis(2-ethylhexyl) phthalate (DEHP) was the only phthalate quantified among the 12 phthalates investigated. This compound was present in 6/7 fin whale samples, 4/7 blue whale samples, 2/5 bowhead whale samples and 1/12 polar bear samples. DEHP concentrations ranged from
PubMed ID
33677245 View in PubMed
Less detail

42 records – page 1 of 5.