Exposing the structure of an Arctic food web.

• Published in: Ecology and Evolution
• Main Authors: Wirta, Helena K., Vesterinen, Eero J., Hambäck, Peter A., Weingartner, Elisabeth, Rasmussen, Claus, Reneerkens, Jeroen, Schmidt, Niels M., Gilg, Olivier, Roslin, Tomas
• Other Authors: Department of Agricultural Sciences, Department of Biology, University of Turku, Department of Ecology, Environment and Plant Sciences, Stockholm University, Department of Bioscience, Aarhus University Aarhus, Aarhus University Aarhus -Arctic Research Centre, Conservation Ecology Group, University of Groningen Groningen -Groningen Institute for Evolutionary Life Sciences, Groupe de recherche en écologie arctique (GREA), Biogéosciences UMR 6282 Dijon (BGS), Université de Bourgogne (UB)-AgroSup Dijon - Institut National Supérieur des Sciences Agronomiques, de l'Alimentation et de l'Environnement-Centre National de la Recherche Scientifique (CNRS), Funding by INTERACT (projects QUANTIC and INTERPRED) under the European Community’s Seventh Framework Programme, by the University of Helsinki (grant number 788/51/2010), by the Academy of Finland (grant number 1276909), by Carl Tryggers Foundation for Scientific Research, by Kone Foundation, by World Wildlife Fund – the Netherlands, by the French Polar Institute – IPEV (program “Interactions”), by Turku University Foundation, by Emil Aaltonen Foundation, by Carlsbergfondet, and by Aage V. JensenCharity Foundation.
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2015
• Subjects: Xysticus; specialism; Plectrophenax; Pardosa; Calidris; DNA barcoding; generalism; Greenland; Hymenoptera; molecular diet analysis; [SDE.BE]Environmental Sciences/Biodiversity and Ecology; [SDV.EE.ECO]Life Sciences [q-bio]/Ecology; environment/Ecosystems; Arctic; Climate change
• Online Access: https://hal.archives-ouvertes.fr/hal-01198620; https://doi.org/10.1002/ece3.1647

15 pages International audience How food webs are structured has major implications for their stability and dynamics. While poorly studied to date, arctic food webs are commonly assumed to be simple in structure, with few links per species. If this is the case, then different parts of the web may be weakly connected to each other, with populations and species united by only a low number of links. We provide the first highly resolved description of trophic link structure for a large part of a high-arctic food web. For this purpose, we apply a combination of recent techniques to describing the links between three predator guilds (insectivorous birds, spiders, and lepidopteran parasitoids) and their two dominant prey orders (Diptera and Lepidoptera). The resultant web shows a dense link structure and no compartmentalization or modularity across the three predator guilds. Thus, both individual predators and predator guilds tap heavily into the prey community of each other, offering versatile scope for indirect interactions across different parts of the web. The current description of a first but single arctic web may serve as a benchmark toward which to gauge future webs resolved by similar techniques. Targeting an unusual breadth of predator guilds, and relying on techniques with a high resolution, it suggests that species in this web are closely connected. Thus, our findings call for similar explorations of link structure across multiple guilds in both arctic and other webs. From an applied perspective, our description of an arctic web suggests new avenues for understanding how arctic food webs are built and function and of how they respond to current climate change. It suggests that to comprehend the community-level consequences of rapid arctic warming, we should turn from analyses of populations, population pairs, and isolated predator-prey interactions to considering the full set of interacting species.