Jair Putzke,

Flávia Ramos Ferrari,

Carlos E.G.R. Schaefer

Polar Research, Journal Year: 2020, Volume and Issue: 39, P. 1 - 15

Published: June 8, 2020

In February 2019, during fieldwork at Harmony Point, Nelson Island, South Shetland Islands, Antarctica, a large population of the rare liverwort Hygrolembidium isophyllum (Lepidoziaceae) was discovered. The occurrence of this rare species reinforces the need to preserve Antarctic Specially Protected Area 133.

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Karina Wieczorek,

Dominik Chłond

Polar Research, Journal Year: 2020, Volume and Issue: 39, P. 1 - 10

Published: May 8, 2020

We report for the first time the presence of the globally distributed and extremely polyphagous pest species—the crescent-marked lily aphid (or mottled arum aphid) (Neomyzus circumflexus L.) (Insecta, Hemiptera, Aphididae)—in Greenland. This species, of alien origin, was found on the ornamental plant Salix arbuscula L., imported from Denmark and sold in the main supermarket of Nuuk, the capital of Greenland. As this species is not the preferred host plant of N. circumflexus, the possibility must be considered that the aphids were not imported along with S. arbuscula from the mainland but were transferred from other imported ornamental plants sold in …

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Piotr Jadwiszczak

Polar Research, Journal Year: 2020, Volume and Issue: 39, P. 1 - 15

Published: June 11, 2020

Humeri have been useful bones in taxonomic determinations of extinct penguins. In the context of neontological taxonomic studies, however, their potential remains unsatisfactorily explored. Here, the variation of the overall closed-outline shape of 60 humeri, assignable to five genera of extant penguins, was investigated. A set of normalized outlines was quantified via elliptical Fourier analysis and subjected to linear discriminant analysis on principal component scores extracted from harmonic coefficients. These geometric representations proved to be a source of easily extractable genus-level taxonomic information. The constructed model provided meaningful discrimination between taxa: the first two linear discriminants captured almost 90% of …

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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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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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Tracy A. Romano,

Laura A. Thompson,

Maureen V. Driscoll,

Ebru Unal,

Allison D. Tuttle,

Gayle Sirpenski,

Mary Ellen Mateleska,

Dale Wolbrink

Polar Research, Journal Year: 2021, Volume and Issue: №40, P. 1 - 16

Published: Nov. 26, 2021

Aquaria that care for and maintain belugas (Delphinapterus leucas) under professional care have the opportunity to contribute to the conservation of wild belugas through research, expertise in animal care and husbandry, and engaging and educating the public about threats to the species’ health and population sustainability. In an aquarium setting, belugas can be studied under controlled conditions, with known variables that are often difficult to discern when studying wild belugas. Information on nutrition, health status and environmental parameters can be easily obtained in a controlled setting. Biological samples are collected from professionally trained whales that voluntarily participate in informative experimental …

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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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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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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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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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