Christian Lydersen,

Kit M. Kovacs

Polar Research, Journal Year: 2021, Volume and Issue: №40, P. 1 - 13

Published: July 15, 2021

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 archipelago of Svalbard spent most of their time foraging close to tidewater glaciers. Transits between glaciers typically followed the coastline, with the whales moving rapidly from one glacier to another. During the later period, the whales spent some time out in the fjords, suggesting that they might be targeting …

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Véronique Lesage

Polar Research, Journal Year: 2021, Volume and Issue: №40, P. 1 - 18

Published: Sept. 3, 2021

Until 2012, the St. Lawrence Estuary beluga population was considered stable with about 1100 individuals. An abnormally high number of calves reported dead that year triggered a population status reassessment. This review article summarizes the findings from this reassessment and various studies subsequent to it and provides an updated analysis of carcass recovery rates up to 2019. The 2013 review indicated a decreased incidence of cancer in adults, suggesting positive impacts from the regulation of toxic substances (e.g., PCBs and PAHs). However, the review also revealed that the population initiated a decline of ca. 1% per year in the early …

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Valeria Vergara,

Jason Wood,

Véronique Lesage,

Audra Ames,

Marie-Ana Mikus,

Robert Michaud

Polar Research, Journal Year: 2021, Volume and Issue: №40, P. 1 - 19

Published: July 15, 2021

Noise and anthropogenic disturbances from vessel traffic are an important threat to the recovery of the endangered St. Lawrence Estuary (SLE) beluga population. The consequences of acoustic masking could be particularly adverse in the case of critical vocalizations that maintain contact between mothers and their dependent but mobile calves. This study models the communication range of adults, sub-adults and newborn beluga contact calls in the presence and absence of vessels in an important summering area for this population. Ambient noise measurements, a composite beluga audiogram and apparent source levels of adult/sub-adult and newborn calls, informed the model. Apparent source levels …

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Jackson R. Ham,

Malin K. Lilley,

Malin R. Miller,

Heather M. Manitzas Hill

Polar Research, Journal Year: 2021, Volume and Issue: №40, P. 1 - 13

Published: July 15, 2021

Belugas (Delphinapterus leucas) in managed care have been reported to show seasonal variation in socio-sexual behaviour, hormone levels and respiration rates; however, little is known about the social interactions of wild belugas when they are not in summer, near-shore congregations. To better understand if belugas show seasonal variation in social interactions, this study recorded the behaviour of 10 belugas (five females, five males, ranging from birth to 10 years of age) housed in managed care. Social interactions typically peaked in the summer months but persisted at very low levels during the rest of the year. Seasonal variation was most dramatic …

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Shengni Duan,

Zhina Jiang,

Min Wen

Polar Research, Journal Year: 2022, Volume and Issue: 41, P. 1 - 14

Published: Jan. 1, 2022

The boreal wintertime atmospheric responses, especially cold events over central Asia, to low sea-ice concentration (SIC) with and without realistic daily variation over the Barents Sea are explored with the Community Atmosphere Model version 4.0 (CAM4.0). The results show that the general atmospheric responses to approximately equal winter-mean Arctic sea-ice loss with a similar pattern but with climatological versus realistic daily variation are different. With the forcing of low SIC with climatological daily variation, Asian cold events become a little longer and stronger than in the control experiment; this mainly results from the enhancement of a 500-hPa Ural anticyclonic anomaly. …

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Dzmitry A. Lukashanets,

Yury H. Hihiniak,

Vladislav Y. Miamin

Polar Research, Journal Year: 2022, Volume and Issue: 41, P. 1 - 15

Published: June 20, 2022

To elucidate poorly known aspects of the microscopic metazoan distribution in ice-free parts of the Antarctic, we examined samples of the multicellular terrestrial alga Prasiola crispa, collected over the last decade in different parts of continental East Antarctica and Haswell Island. We found that the micrometazoans inhabiting the algae consist of remarkably abundant bdelloid rotifers (subclass Bdelloidea), followed by tardigrades. We did not find nematodes. The rotifer assemblages were characterized by low diversity (only six species). Nevertheless, rotifer densities were extremely high: mean densities ranged from 75 to 3030 individuals per 100 mg of the dry sample weight and the …

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Stephen M. Chignell,

Adrian Howkins,

Poppie Gullett,

Andrew G. Fountain

Polar Research, Journal Year: 2022, Volume and Issue: 41, P. 1 - 16

Published: June 4, 2022

Co-authorship networks can provide key insights into the production of scientific knowledge. This is particularly interesting in Antarctica, where most human activity relates to scientific research. Bibliometric studies of Antarctic science have provided a useful understanding of international and interdisciplinary collaboration, yet most research has focused on broad-scale analyses over recent time periods. Here, we take advantage of a ‘Goldilocks’ opportunity in the McMurdo Dry Valleys, an internationally important region of Antarctica and the largest ice-free region on the continent. The McMurdo Dry Valleys have attracted continuous and diverse scientific activity since 1958. It is a geographically confined region with …

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Martyn E. Obbard,

Christopher Di Corrado,

João Franco,

Roger Pimenta,

Boris Wise

Polar Research, Journal Year: 2022, Volume and Issue: 41, P. 1 - 6

Published: April 12, 2022

Sea-ice distribution and duration are declining across the circumpolar range of the polar bear (Ursus maritimus), resulting in a reduced access to ice-obligate seals, its primary prey. Consequently, polar bears may have increased reliance on alternative food sources in the future. Foraging on land is well documented but foraging in open water is less understood. We report the successful depredation of a thick-billed murre (Uria lomvia) in open water near Prince Leopold Island, Nunavut, and discuss implications for understanding the behavioural plasticity of polar bears and their opportunistic foraging patterns.

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Øystein Varpe,

Geir W. Gabrielsen

Polar Research, Journal Year: 2022, Volume and Issue: 41, P. 1 - 6

Published: Nov. 9, 2022

Seabirds in cold biomes sometimes aggregate near glacier fronts and at sea-ice edges to forage. In this note, we report on large aggregations of black guillemots (Cepphus grylle) at the edge of sea ice in front of the tidewater glacier Kongsbreen (Kongsfjorden, Svalbard). During several days in the second half of June 2011, we observed 49–155 individuals of black guillemots at this ice edge. They foraged actively, and many of the dives were directed underneath the sea ice. The outflow of glacial meltwater and resulting upwelling generated opportunities for the black guillemots to feed, likely on zooplankton or fish. The …

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Chuan Chen

Polar Research, Journal Year: 2022, Volume and Issue: 41, P. 1 - 7

Published: March 17, 2022

With China becoming more active in Greenland, worries abound that China might have hidden intentions. Despite that, the Greenlandic government is showing an increasing interest in deepening its cooperation with China. This article explores Greenland’s motivation behind its positive attitude towards China and examines whether China will be a threat to Greenland’s independence. For Greenland, China is both a deep-pocketed investor and a huge consumer market, especially in the mining, fishing and tourism industries. Greenland, therefore, views China as an important partner in its economic development, which is necessary for its independence from Denmark. Considering China’s relationship with Denmark, its …

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