Abundance, habitat use and food consumption of seabirds in the high-Arctic fjord ecosystem

AbstractTo monitor the rapid changes occurring in Arctic ecosystems and predict their direction, basic information about the current number and structure of the main components of these systems is necessary. Using boat-based surveys, we studied the numbers and distribution of seabirds foraging in Hornsund (SW Spitsbergen) during three summer seasons. The average number of seabirds foraging concurrently in the whole fjord was estimated at 28,000. Little Auks Alle alle were the most numerous, followed by Northern Fulmars Fulmarus glacialis, Brünnich’s Guillemots Uria lomvia and Black-legged Kittiwakes Rissa tridactyla. The pelagic zone was exploited by some 75% of the birds. Their density was the highest (> 400 ind. km−2) in the tidewater glacier bays, where kittiwakes were predominant, and the lowest in the coastal glacier bays. The seabirds in Hornsund daily consumed c. 12.7 tons of food, i.e. c. 0.2% of the summer mesozooplankton and fish standing stocks available in the fjord. This food consisted primarily of copepods, amphipods and molluscs (c. 70%), whereas fish made up < 15%. More than 50% of this biomass was ingested by pursuit divers, while surface feeders took c. 29% and benthophages c. 13%. About three-quarters of the food biomass was taken from the pelagic zone. This paper describes, for the first time in quantitative terms, the structure and function of a seabird community foraging in an Arctic fjord. It also provides a baseline for future studies on climate-induced changes in the importance of seabirds in the Arctic food web.

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Seasonal change and microhabitat association of Arctic spider assemblages (Arachnida: Araneae) on Victoria Island (Nunavut, Canada)

The Canadian Entomologist ◽

10.4039/tce.2017.6 ◽

2017 ◽

Vol 149 (3) ◽

pp. 357-371 ◽

Cited By ~ 5

Author(s):

Elyssa R. Cameron ◽

Christopher M. Buddle

Keyword(s):

Seasonal Change ◽

Ecological Monitoring ◽

High Arctic ◽

The Arctic ◽

Arctic Ecosystems ◽

Active Season ◽

The North ◽

Arthropod Predators ◽

Abundance And Diversity ◽

Victoria Island

AbstractArctic ecosystems are characterised by a mosaic of distinct microhabitats, which play a key role in structuring biodiversity. Understanding species diversity in relation to these microhabitats, and how communities are structured seasonally, is imperative to properly conserve, monitor, and manage northern biodiversity. Spiders (Arachnida: Araneae) are dominant arthropod predators in the Arctic, yet the seasonal change in their communities in relation to microhabitat variation is relatively unknown. This research quantified how spider assemblages are structured seasonally and by microhabitat, near Cambridge Bay, Nunavut, Canada. In 2014, spiders were collected in 240 pan and pitfall traps placed in common microhabitat types (two wet and two dry) from 3 July to 11 August, the active season in the high Arctic. In total, 10 353 spiders from 22 species and four families were collected. Non-metric multidimensional scaling ordinations revealed that spider assemblages from wet habitats were distinct from those occurring in drier habitats, but that differences within each of those habitats were not evident. Abundance and diversity was highest in wet habitats and differed significantly from dry habitats; both these variables decreased seasonally. Spider assemblages in the north are structured strongly along moisture gradients, and such data informs planning for future ecological monitoring in the Arctic.

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Birds of three worlds: moult migration to high Arctic expands a boreal-temperate flyway to a third biome

Movement Ecology ◽

10.1186/s40462-021-00284-4 ◽

2021 ◽

Vol 9 (1) ◽

Author(s):

Antti Piironen ◽

Antti Paasivaara ◽

Toni Laaksonen

Keyword(s):

Bird Migration ◽

High Arctic ◽

The Arctic ◽

Migratory Connectivity ◽

Migration Routes ◽

Arctic Ecosystems ◽

Long Distance ◽

Novaya Zemlya ◽

Bean Goose ◽

Moult Migration

Abstract Background Knowledge on migration patterns and flyways is a key for understanding the dynamics of migratory populations and evolution of migratory behaviour. Bird migration is usually considered to be movements between breeding and wintering areas, while less attention has been paid to other long-distance movements such as moult migration. Methods We use high-resolution satellite-tracking data from 58 taiga bean geese Anser fabalis fabalis from the years 2019–2020, to study their moult migration during breeding season. We show the moulting sites, estimate the migratory connectivity between the breeding and the moulting sites, and estimate the utilization distributions during moult. We reveal migration routes and compare the length and timing of migration between moult migrants and successful breeders. Results All satellite-tracked non-breeding and unsuccessfully breeding taiga bean geese migrated annually to the island of Novaya Zemlya in the high Arctic for wing moult, meaning that a large part of the population gathers at the moulting sites outside the breeding range annually for approximately three months. Migratory connectivity between breeding and moulting sites was very low (rm = − 0.001, 95% CI − 0.1562–0.2897), indicating that individuals from different breeding grounds mix with each other on the moulting sites. Moult migrants began fall migration later in autumn than successful breeders, and their overall annual migration distance was over twofold compared to the successful breeders. Conclusions Regular moult migration makes the Arctic an equally relevant habitat for the taiga bean goose population as their boreal breeding and temperate wintering grounds, and links ecological communities in these biomes. Moult migration plays an important role in the movement patterns and spatio-temporal distribution of the population. Low migratory connectivity between breeding and moulting sites can potentially contribute to the gene flow within the population. Moult migration to the high Arctic exposes the population to the rapid impacts of global warming to Arctic ecosystems. Additionally, Novaya Zemlya holds radioactive contaminants from various sources, which might still pose a threat to moult migrants. Generally, these results show that moult migration may essentially contribute to the way we should consider bird migration and migratory flyways.

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The Effects of Predicted Soil Moisture and Temperature Increase on CO2 Exchange within a High Arctic Ecosystem

Inquiry@Queen's Undergraduate Research Conference Proceedings ◽

10.24908/iqurcp.9990 ◽

2018 ◽

Author(s):

Sarah Jackson

Keyword(s):

Soil Moisture ◽

Soil Temperature ◽

Co2 Flux ◽

High Arctic ◽

Co2 Exchange ◽

The Arctic ◽

Co2 Production ◽

Arctic Ecosystems ◽

Arctic Regions ◽

Snow Fences

With 2014 being the warmest year on record and 10 of the warmest years occurring after 1997, it is essential to understand the effects of this warming on CO2 exchange. It was also discovered that much of this warming is focused in the Arctic regions, which are sensitive to changes in temperature (Cole & McCarthy, 2015). My research examines the effects of enhanced snowfall and soil temperature on the exchange of CO2 between the land and the atmosphere in a high arctic environment. The research is taking place at Cape Bounty Arctic Watershed Observatory (CBAWO) on Melville Island, Nunavut as part of the International Tundra Experiment (ITEX). The goal of ITEX is to better understand the effects of increased summer temperature and increased snowfall on arctic ecosystems. This is a full factorial experiment including treatments varying precipitation (and likely soil moisture), soil temperature, moisture and temperature together, and a control that is at ambient soil moisture and temperature. Snow fences are used to enhance precipitation, while open-topped transparent chambers are used to increase soil temperature. In a companion lab experiment, I look at the effects of different soil moisture levels and temperatures on soil CO2 production in a more controlled environment. Two temperatures, two moisture levels, and eight replicates of each will be established in sealed incubation chambers, and soils will be incubated for 33 days. Presently a significant relationship has been found between soil moisture and CO2 flux within the field experiment.

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Microscale drivers of summer CO2 fluxes in the Svalbard High Arctic tundra

Scientific Reports ◽

10.1038/s41598-021-04728-0 ◽

2022 ◽

Vol 12 (1) ◽

Author(s):

Marta Magnani ◽

Ilaria Baneschi ◽

Mariasilvia Giamberini ◽

Brunella Raco ◽

Antonello Provenzale

Keyword(s):

Ecosystem Respiration ◽

Vegetation Type ◽

Gross Primary Production ◽

Arctic Tundra ◽

High Arctic ◽

The Arctic ◽

Small Scale ◽

Arctic Ecosystems ◽

Additional Source ◽

And Storage

AbstractHigh-Arctic ecosystems are strongly affected by climate change, and it is still unclear whether they will become a carbon source or sink in the next few decades. In turn, such knowledge gaps on the drivers and the processes controlling CO2 fluxes and storage make future projections of the Arctic carbon budget a challenging goal. During summer 2019, we extensively measured CO2 fluxes at the soil–vegetation–atmosphere interface, together with basic meteoclimatic variables and ecological characteristics in the Bayelva river basin near Ny Ålesund, Spitzbergen, Svalbard (NO). By means of multi-regression models, we identified the main small-scale drivers of CO2 emission (Ecosystem Respiration, ER), and uptake (Gross Primary Production, GPP) in this tundra biome, showing that (i) at point scale, the temporal variability of fluxes is controlled by the classical drivers, i.e. air temperature and solar irradiance respectively for ER and GPP, (ii) at site scale, the heterogeneity of fractional vegetation cover, soil moisture and vegetation type acted as additional source of variability for both CO2 emissions and uptake. The assessment of the relative importance of such drivers in the multi-regression model contributes to a better understanding of the terrestrial carbon dioxide exchanges and of Critical Zone processes in the Arctic tundra.

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Effects of fertilization on three tundra plant communities of a polar desert oasis

Canadian Journal of Botany ◽

10.1139/b86-332 ◽

1986 ◽

Vol 64 (11) ◽

pp. 2502-2507 ◽

Cited By ~ 79

Author(s):

G. H. R. Henry ◽

B. Freedman ◽

J. Svoboda

Keyword(s):

Plant Communities ◽

High Arctic ◽

Ellesmere Island ◽

Nutrient Addition ◽

The Arctic ◽

Arctic Ecosystems ◽

Polar Desert ◽

Net Production ◽

Dwarf Shrubs ◽

Desert Oasis

Three plant communities studied at a high arctic oasis on Ellesmere Island responded to nutrient addition. Response to nitrogen was greatest in the driest community and weaker in the more mesic and wet-mesic communities. Nutrient addition resulted in (i) increased inflorescence densities of dicotyledonous and certain graminoid species; (ii) increased tiller densities of wet sedge species; and (iii) increased net production of graminoids and forbs at high rates of application, and in some dwarf shrubs at lower rates. These results parallel those of studies at lower latitudes in the Arctic, and support the hypothesis that arctic ecosystems are typically oligotrophic.

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Net greenhouse gas fluxes from three High Arctic plant communities along a moisture gradient

Arctic Science ◽

10.1139/as-2018-0018 ◽

2019 ◽

Vol 5 (4) ◽

pp. 185-201 ◽

Cited By ~ 2

Author(s):

Ioan Wagner ◽

Jacqueline K.Y. Hung ◽

Allison Neil ◽

Neal A. Scott

Keyword(s):

Greenhouse Gas ◽

Vegetation Cover ◽

High Arctic ◽

Moisture Gradient ◽

Gas Production ◽

The Arctic ◽

Environmental Drivers ◽

Arctic Ecosystems ◽

Gas Fluxes ◽

Tundra Ecosystem

Climate in high latitude environments is predicted to undergo a pronounced warming and increase in precipitation, which may influence the terrestrial moisture gradients that affect vegetation distribution. Vegetation cover can influence rates of greenhouse gas production through differences in microbial communities, plant carbon uptake potential, and root transport of gases out of the soil into the atmosphere. To predict future changes in greenhouse gas production from High Arctic ecosystems in response to climate change, it is important to understand the interaction between trace gas fluxes and vegetation cover. During the growing seasons of 2008 and 2009, we used dark static chambers to measure CH4 and N2O fluxes and CO2 emissions at Cape Bounty, Melville Island, NU, across a soil moisture gradient, as reflected by their vegetation cover. In both years, wet sedge had the highest rates of emission for all trace gases, followed by the mesic tundra ecosystem. CH4 consumption was highest in the polar semi-desert, correlating positively with temperature and negatively with moisture. Our findings demonstrate that net CH4 uptake may be largely underestimated across the Arctic due to sampling bias towards wetlands. Overall, greenhouse gas flux responses vary depending on different environmental drivers, and the role of vegetation cover needs to be considered in predicting the trajectory of greenhouse gas uptake and release in response to a changing climate.

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Effects of Permafrost Disturbance on Trace Gas Flux in a High Arctic Ecosystem

Inquiry@Queen's Undergraduate Research Conference Proceedings ◽

10.24908/iqurcp.8730 ◽

2016 ◽

Author(s):

Alison Beamish

Keyword(s):

Active Layer ◽

Global Climate ◽

High Arctic ◽

Co2 Exchange ◽

The Arctic ◽

Trace Gas ◽

Arctic Ecosystems ◽

Gas Flux ◽

Temperature And Precipitation ◽

The Impact

High Arctic ecosystems are likely to experience some of the earliest and most extreme changes in climate as a result of future global climate change. These changes will likely include both increases in temperature and precipitation. High-Arctic ecosystems are very sensitive to climatic disruption, and the response of these ecosystems to changes in climate could have a strong influence on future climate. In particular, changes in temperature and moisture will cause the active layer to deepen as a result of enhanced permafrost melting. This deepening will decrease stability in shallow slopes leading to soil disturbances known as active layer detachments.. We are exploring the impact of active layer detachments on net ecosystem trace gas (CH4, N2O and CO2) exchange at the Cape Bounty Arctic Watershed Observatory on Melville Island. Eight plots were established in four different detachments, covering a range of disturbance intensities (control, disturbed and highly disturbed). Based on collected and analysed gas samples, it appears disturbance has an effect on trace gas exchange. Initial results show a distinct difference across the disturbance gradient. These findings have important implications if summer temperatures are to rise and disturbance frequency increases. Continued monitoring of these sites is important to assess the changes in trace gas flux over time since disturbance. Quantifying the impact of active layer detachments is crucial to furthering our understanding of the arctic carbon and trace gas cycles.

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Congruent responses to weather variability in high arctic herbivores

Biology Letters ◽

10.1098/rsbl.2012.0764 ◽

2012 ◽

Vol 8 (6) ◽

pp. 1002-1005 ◽

Cited By ~ 57

Author(s):

Audun Stien ◽

Rolf A. Ims ◽

Steve D. Albon ◽

Eva Fuglei ◽

R. Justin Irvine ◽

...

Keyword(s):

Life Histories ◽

Rangifer Tarandus ◽

Trophic Position ◽

High Arctic ◽

Climate Impact ◽

Climate Impacts ◽

The Arctic ◽

Polar Regions ◽

Arctic Ecosystems ◽

Wildlife Populations

Assessing the role of weather in the dynamics of wildlife populations is a pressing task in the face of rapid environmental change. Rodents and ruminants are abundant herbivore species in most Arctic ecosystems, many of which are experiencing particularly rapid climate change. Their different life-history characteristics, with the exception of their trophic position, suggest that they should show different responses to environmental variation. Here we show that the only mammalian herbivores on the Arctic islands of Svalbard, reindeer ( Rangifer tarandus ) and sibling voles ( Microtus levis ), exhibit strong synchrony in population parameters. This synchrony is due to rain-on-snow events that cause ground ice and demonstrates that climate impacts can be similarly integrated and expressed in species with highly contrasting life histories. The finding suggests that responses of wildlife populations to climate variability and change might be more consistent in Polar regions than elsewhere owing to the strength of the climate impact and the simplicity of the ecosystem.

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Recent contrasting behaviour of mountain glaciers across the European High Arctic revealed by ArcticDEM data

10.5194/tc-2021-165 ◽

2021 ◽

Author(s):

Jakub Małecki

Keyword(s):

Climate Models ◽

Barents Sea ◽

High Arctic ◽

The Arctic ◽

Arctic Ecosystems ◽

Mountain Glacier ◽

Novaya Zemlya ◽

Mountain Glaciers ◽

The Barents Sea ◽

Recent Climate

Abstract. Small land-terminating mountain glaciers are a widespread and important element of Arctic ecosystems, influencing local hydrology, microclimate, and ecology, among others. Due to little ice volumes, this class of ice masses is very sensitive to climate warming, the latter of which is extremely well manifested in the European sector of the Arctic, i.e. in the Barents Sea area. Archipelagos surrounding the Barents Sea, i.e. Svalbard (SV), Novaya Zemlya (NZ), and Franz Josef Land (FJ), host numerous populations of mountain glaciers, but their response to recent strong warming remains understudied in most locations. This paper aims to obtain a snapshot of their state by utilizing high-resolution elevation data (ArcticDEM) to investigate the recent (ca. 2011–2017) elevation and volume changes of 382 small glaciers across SV, NZ, and FJ. The study concludes that many mountain glacier sites across the Barents Sea have been in a critical imbalance with the recent climate and might melt away within the coming several decades. However, deviations from the general trend exist, e.g. a cluster of small glaciers in north SV experiencing thickening. The findings reveal that near-stagnant glaciers might exhibit contrasting behaviours (fast thinning vs. thickening) over relatively short distances, being a challenge for climate models, but also an opportunity to test their reliability.

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Methane in Zackenberg Valley, NE Greenland: Multidecadal growing season fluxes of a high Arctic tundra

10.5194/bg-2021-70 ◽

2021 ◽

Author(s):

Johan H. Scheller ◽

Mikhail Mastepanov ◽

Hanne H. Christiansen ◽

Torben R. Christensen

Keyword(s):

Critical Role ◽

Terrestrial Ecosystems ◽

Methane Flux ◽

High Arctic ◽

Landscape Scale ◽

The Arctic ◽

Atmospheric Methane ◽

Arctic Ecosystems ◽

Atmospheric Concentration ◽

Methane Fluxes

Abstract. The carbon balance of high-latitude terrestrial ecosystems plays an essential role in the atmospheric concentration of trace gases, including carbon dioxide (CO2) and methane (CH4). Increasing levels of atmospheric methane have contributed to ~20 % of the observed global warming since the pre-industrial era. Rising temperatures in the Arctic are expected to promote the release of methane from Arctic ecosystems. Still, existing methane flux data collection efforts are sparse and highly scattered, and further attempts to assess the landscape fluxes over multiple years are needed.Here we use multiyear monitoring from automated flux chambers located on the fringe of a fen area in the center of Zackenberg Valley, northeast Greenland, from July and August (2006–2019). Direct measurements of methane fluxes showed high variability, with mean July–August fluxes ranging from 0.26 to 3.41 mg CH4 m−2 h−1. Methane fluxes based on manual chamber measurements are available from campaigns in 1997, 1999–2000, and in shorter periods from 2007–2013 and have been summarized in several published studies. Fluxes from the multiyear monitoring were combined with fluxes from the most common vegetation types, measured in 2007, and a detailed vegetation cover map to assess the methane flux on a landscape-scale and its variability over time.July–August landscape fluxes, estimated in the current study for the 2006–2019 period, were low compared to previous estimations. For the full study area covering the valley floor, the net methane source during these months was estimated as 0.06 to 0.83 mg CH4 m−2 h−1 and as 0.26 to 3.45 mg CH4 m−2 h−1 for the central fen-rich areas.A 2017–2018 erosion event indicates that some fen and grassland areas along the river in the center of the valley are becoming unstable following pronounced fluvial erosion and a prolonged period of permafrost warming. Although such physical disturbance in the landscape can disrupt the current ecosystem–atmosphere flux patterns, even pronounced future erosion along the river is unlikely to impact methane fluxes at a landscape-scale significantly. Instead, projected changes in future climate in the valley play a more critical role. The results show that multiyear landscape methane fluxes are highly variable at a landscape-scale and stress the need for long-term spatially distributed measurements in the Arctic.

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