Rough-legged buzzards, Arctic foxes and red foxes in a tundra ecosystem without rodents

PLoS One. 2015 Feb 18;10(2):e0118740. doi: 10.1371/journal.pone.0118740. eCollection 2015.

Abstract

Small rodents with multi-annual population cycles strongly influence the dynamics of food webs, and in particular predator-prey interactions, across most of the tundra biome. Rodents are however absent from some arctic islands, and studies on performance of arctic predators under such circumstances may be very instructive since rodent cycles have been predicted to collapse in a warming Arctic. Here we document for the first time how three normally rodent-dependent predator species-rough-legged buzzard, arctic fox and red fox - perform in a low-arctic ecosystem with no rodents. During six years (in 2006-2008 and 2011-2013) we studied diet and breeding performance of these predators in the rodent-free Kolguev Island in Arctic Russia. The rough-legged buzzards, previously known to be a small rodent specialist, have only during the last two decades become established on Kolguev Island. The buzzards successfully breed on the island at stable low density, but with high productivity based on goslings and willow ptarmigan as their main prey - altogether representing a novel ecological situation for this species. Breeding density of arctic fox varied from year to year, but with stable productivity based on mainly geese as prey. The density dynamic of the arctic fox appeared to be correlated with the date of spring arrival of the geese. Red foxes breed regularly on the island but in very low numbers that appear to have been unchanged over a long period - a situation that resemble what has been recently documented from Arctic America. Our study suggests that the three predators found breeding on Kolguev Island possess capacities for shifting to changing circumstances in low-arctic ecosystem as long as other small - medium sized terrestrial herbivores are present in good numbers.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Arctic Regions
  • Dinosaurs / physiology*
  • Foxes / physiology*
  • Nesting Behavior
  • Population Dynamics
  • Predatory Behavior
  • Tundra

Grants and funding

This study was funded by Institute for Waterbird and Wetlands Research (IWWR) e.V., UiT - Arctic University of Norway, The Norwegian Environment Agency, Conservation Arctic Flora and Fauna (CAFF) and Max-Planck Institute for Ornithology. The authors would also like to thank the German Committee for Bird Protection (VsK, Hamburg) and the ECORA GEF Project for financial support of their expeditions 2006-2012. In 2011 and 2012 this study was part of a project of the Institute of Avian Research, the Department of Biology and Environmental Science, University of Oldenburg, IWWR e.V. and the Wadden Sea National Park Administration of Lower Saxony, which was funded by the Federal Agency for Nature Conservation under the Federal Ministry for the Environment, Nature Conservation and Nuclear Safety (FKZ 3510 860 1000), the Niedersächsische Wattenmeerstiftung and the Committee for Bird Protection VsK. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.