Incomplete degradation of lichen usnic acid and atranorin in Svalbard reindeer (Rangifer tarandus platyrhynchus)

Michał Hubert Węgrzyn,

Beata Cykowska-Marzencka,

Monica Alterskjær Sundset,

Paulina Wietrzyk-Pełka,

Agnieszka Galanty

Опубликована Янв. 22, 2019

Previous studies of Eurasian tundra reindeer (Rangifer tarandus tarandus) in Norway indicate that their rumen microbiota play a key role in degrading lichen secondary metabolites. We investigated the presence of usnic acid and atranorin in faecal samples from Svalbard reindeer (R. tarandus platyrhynchus). Samples were collected in Bolterdalen valley together with vegetation samples from the study site. The mesic tundra in this area was dominated by vascular plants (59% of vegetation cover). Bryophytes (16%) and lichens (25%) were also present. Qualitative and quantitative analyses of usnic acid and atranorin in lichen and faeces samples were performed using high-performance liquid chromatography. …

Pseudolamarckina pseudorjasanensis Dain, 1967 (Foraminifera) as a Kimmeridgian marker species and its significance for biostratigraphy, palaeoecology and palaeobiogeography

Clémentine Peggy Anne-Marie Colpaert,

Boris Leonidovich Nikitenko

Опубликована Март 5, 2019

This study presents a taxonomical review of the species Pseudolamarckina pseudorjasanensis Dain, 1967 collected at different sampling levels from the central and northern parts of European Russia and from Western Siberia. Morphological and biometrical analyses show that P. pseudorjasanensis is characterized by wide intraspecific variabilities and may encompass various previously described Kimmeridgian species of the genus Pseudolamarckina. The first appearance of P. pseudorjasanensis is recorded from the latest Early Kimmeridgian of sub-Mediterranean to Arctic regions. Furthermore, P. pseudorjasanensis appears to be the marker species of the foraminiferal JF41 Zone in Kimmeridgian sections of sub-boreal, boreal and Arctic regions. This JF41 …

A multi-year study of narwhal occurrence in the western Fram Strait—detected via passive acoustic monitoring

Heidi Ahonen,

Kathleen M. Stafford,

Christian Lydersen,

Laura de Steur,

Kit M. Kovacs

Опубликована Март 6, 2019

Passive acoustic monitoring (PAM) has proven to be an efficient method for studying vocally active marine mammals in areas that are difficult to access on a year-round basis. In this study, a PAM recorder was deployed on an oceanographic mooring in western Fram Strait (78°50'N, 5°W) to record the acoustic presence of narwhals (Monodon monoceros) over a 3-yr period. Acoustic data were recorded for 14–17 min at the start of each hour from 25 September 2010 to 26 August 2011, from 2 September 2012 to 11 April 2013 and from 8 September 2013 to 27 April 2014. Pulsed and tonal …

Summer habitat selection by ringed seals (Pusa hispida) in the drifting sea ice of the northern Barents Sea

Karen Lone,

Jon Aars,

Christian Lydersen,

Kit M. Kovacs,

Charmain D. Hamilton

Опубликована Сен. 13, 2019

Ringed seals are a central component of the Arctic ecosystem; they have a circumpolar distribution and are both important predators of lower trophic animals (invertebrates and fishes) and prey for polar bears and coastal human populations. They depend on sea ice for reproduction, moulting and resting, and they consume significant amounts of ice-associated prey. The population of ringed seals in Svalbard, Norway, uses both coastal and offshore habitats, the latter being important during seasonal migrations undertaken by some animals, mostly juveniles. This study examined habitat preferences of 18 satellite-tracked ringed seals (mostly young animals, but also a few adults) during …

The effect of an experimental decrease in salinity on the viability of the Subarctic planktonic foraminifera Neogloboquadrina incompta

Mattia Greco,

Tine L. Rasmussen,

Michal Kucera,

Julie Meilland,

Kasia Zamelczyk

Опубликована Авг. 27, 2020

Chemical signatures in the calcite of shells of polar and subpolar planktonic foraminifera have been frequently used to trace and quantify past meltwater discharge events. This approach assumes that the foraminifera can tolerate low salinity under extended periods. To obtain a first experimental constraint on salinity tolerance of Subarctic foraminifera, we carried out a culturing experiment with specimens of the subpolar species Neogloboquadrina incompta collected in the northern Norwegian Sea off Tromsø in October 2018. The foraminifera were exposed to a gradient of salinities between 35 and 25 PSU. Survival was monitored over 26 days by measuring the extent of …

Temporal and spatial change in the relationship between sea-ice motion and wind in the Arctic

Ken Maeda,

Noriaki Kimura,

Hajime Yamaguchi

Опубликована Ноя. 26, 2020

This paper examines the temporal and spatial change in the characteristics of sea-ice motion in the Arctic. Ice motion is generally expressed by a motion at a constant ratio (wind factor) of wind speed, with a certain angle (turning angle) from the wind direction, and ocean currents. This study aimed to reveal the recent changes of the wind factor and turning angle using satellite observation data. We first prepared a daily ice-velocity data set from data for 2003–2017 collected by the satellite microwave sensor Advanced Microwave Scanning Radiometer for the Earth Observing System (AMSR-E) and its successor, AMSR2. Monthly values …

Outline shape analysis of penguin humeri: a robust approach to taxonomic classification

Piotr Jadwiszczak

Опубликована Июнь 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 …

Sharing country food: connecting health, food security and cultural continuity in Chesterfield Inlet, Nunavut

Sarah L. Newell,

Nancy C. Doubleday,

Community of Chesterfield Inlet, Nunavut

Опубликована Дек. 23, 2020

Food security is a complex topic defined not just by having enough nutritious food to eat but also by cost, safety and cultural considerations. In Arctic Inuit communities, food security is intimately connected to culture through traditional methods of harvesting country food. In Chesterfield Inlet, Nunavut, community-based research was conducted in collaboration with Chesterfield Inlet community members using interviews and community engagement. Community members were consulted about the design of the interview guide, recruitment of participants, analysis and validation of results. This study aims to develop a theoretical framework of how food security, cultural continuity and community health and well-being …

Marine debris on two Arctic beaches in the Russian Far East

Henrik Kylin

Опубликована Ноя. 6, 2020

In August 2005, marine debris was counted on two Arctic beaches in the Russian Far East. On the north coast of the Chukchi Peninsula east of Kolyuchin Bay, a beach stretch of ca. 2.4 km held a total of 736 items, 0.024 items m‑2, while no more than 0.0011 items m‑2, 12 items in total, were found on a beach stretch of ca. 1.2 km on southern Wrangel Island. The likely explanation for this difference is that the area around the mainland beach is ice-free for a longer period each year, but a contributing factor may be that late spring …

Discovery of a large population of Hygrolembidium isophyllum (Lepidoziaceae, Marchantiophyta) in the South Shetland Islands, Antarctica

Jair Putzke,

Flávia Ramos Ferrari,

Carlos E.G.R. Schaefer

Опубликована Июнь 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.