Snow covers the ground over large parts of the world for a substantial portion of the year. Yet very few methods are available to quantify biotic variables below the snow, with most studies of subnivean ecological processes relying on comparisons of data before and after the snow cover season. We developed a camera trap prototype to quantify subnivean small mammal activity. The trap consists of a camera that is attached facing downward from the ceiling...
Capture–recapture software packages have proven to be very powerful tools for analysing factors affecting survival in wild populations. However, all such packages are limited to discrete-time protocols. Appropriate survival analysis tools are still lacking for data acquired from continuous-time protocols. We have developed a statistical method and propose an r package for analysing such data based on an extension of classical survival analysis models incorporating an inhomogeneous Poisson process for modelling capture histories. First, data...
Spatial variation in the strength of trophic cascades in arctic tundra has been related to flows of subsidies across ecosystem boundaries. Here, we ask whether the input of marine subsidies in tundra systems would cause spatial variation in the strength of rodent-plant interactions between coastal areas, where predators have access to marine-derived resources, and non-subsidized inland areas of northern Fennoscandia. We present a detailed evaluation of predator-rodent-vegetation interactions along a coast-inland gradient, during the 2011...
Several decades of research on invasive marine species have yielded a broad understanding of the nature of species invasion mechanisms and associated threats globally. However, this is not true of the Arctic, a region where ongoing climatic changes may promote species invasion. Here, we evaluated risks associated with non-indigenous propagule loads discharged with ships' ballast water to the high-Arctic archipelago, Svalbard, as a case study for the wider Arctic. We sampled and identified transferred propagules...
Data from: Climate change alters the structure of arctic marine food webs due to poleward shifts of boreal generalistsSusanne Kortsch, Raul Primicerio, Maria Fossheim, Andrey V. Dolgov & Michaela Aschan
Climate-driven poleward shifts, leading to changes in species composition and relative abundances, have been recently documented in the Arctic. Among the fastest moving species are boreal generalist fish which are expected to affect arctic marine food web structure and ecosystem functioning substantially. Here, we address structural changes at the food web level induced by poleward shifts via topological network analysis of highly resolved boreal and arctic food webs of the Barents Sea. We detected considerable...
Data from: The role of a dominant predator in shaping biodiversity over space and time in a marine ecosystemKari Elsa Ellingsen, Marti J. Anderson, Nancy L. Shackell, Torkild Tveraa, Nigel G. Yoccoz & Kenneth T. Frank
1. Exploitation of living marine resources has resulted in major changes to populations of targeted species and functional groups of large-bodied species in the ocean. However, the effects of overfishing and collapse of large top predators on the broad-scale biodiversity of oceanic ecosystems remain largely unexplored. 2. Populations of the Atlantic cod (Gadus morhua) were overfished and several collapsed in the early 1990s across Atlantic Canada, providing a unique opportunity to study potential ecosystem-level effects...
Data from: Lake size and fish diversity determine resource use and trophic position of a top predator in high-latitude lakesAntti P. Eloranta, Kimmo K. Kahilainen, Per-Arne Amundsen, Rune Knudsen, Chris Harrod & Roger I. Jones
Prey preference of top predators and energy flow across habitat boundaries are of fundamental importance for structure and function of aquatic and terrestrial ecosystems, as they may have strong effects on production, species diversity, and food-web stability. In lakes, littoral and pelagic food-web compartments are typically coupled and controlled by generalist fish top predators. However, the extent and determinants of such coupling remains a topical area of ecological research and is largely unknown in oligotrophic...
Data from: Highly overlapping winter diet in two sympatric lemming species revealed by DNA metabarcodingEeva M. Soininen, Gilles Gauthier, Frédéric Bilodeau, Dominique Berteaux, Ludovic Gielly, Pierre Taberlet, Galina Gussarova, Eva Bellemain, Kristian Hassel, Hans K. Stenøien, Laura Epp, Audun Schrøder-Nilsen, Christian Brochmann, Nigel G. Yoccoz & Audun Schrøder-Nielsen
Sympatric species are expected to minimize competition by partitioning resources, especially when these are limited. Herbivores inhabiting the High Arctic in winter are a prime example of a situation where food availability is anticipated to be low, and thus reduced diet overlap is expected. We present here the first assessment of diet overlap of high arctic lemmings during winter based on DNA metabarcoding of feces. In contrast to previous analyses based on microhistology, we found...
Sparse, incomplete and inappropriate historical records of invasive species often hamper invasive species management interventions. Population genetic analyses of invaders might provide a suitable context for the identification of their source populations and possible introduction routes. Here, we describe the population genetics of Heracleum persicum Desf. ex Fisch and trace its route of introduction into Europe. Microsatellite markers revealed a significantly higher genetic diversity of H. persicum in its native range, and the loss of...
Polar Regions are experiencing environmental changes at unprecedented rates. These changes can spread throughout entire food webs from lower trophic levels to apex predators. As many top predators forage over large areas, these indirect effects may be associated with large-scale patterns of climate variability. Using global climate indices that are known to impact the Southern Ocean ecosystem (the El Niño Southern Oscillation and Antarctic Oscillation Indices) we assessed their efficacy to predict variation in the...
The Arctic University of Norway10
Norwegian Institute for Nature Research3
University Centre in Svalbard2
National Taiwan Normal University2
Norwegian Institute of Marine Research2
Institute of Systematics and Ecology of Animals1
Knipovich Polar Research Institute of Marine Fisheries and Oceanography1
Polish Academy of Sciences1
University of Windsor1
University of Tasmania1