, Volume 178, Issue 3, pp 915–929 | Cite as

How will the greening of the Arctic affect an important prey species and disturbance agent? Vegetation effects on arctic ground squirrels

  • H. C. Wheeler
  • J. D. Chipperfield
  • C. Roland
  • J.-C. Svenning
Global change ecology - Original research


Increases in terrestrial primary productivity across the Arctic and northern alpine ecosystems are leading to altered vegetation composition and stature. Changes in vegetation stature may affect predator–prey interactions via changes in the prey’s ability to detect predators, changes in predation pressure, predator identity and predator foraging strategy. Changes in productivity and vegetation composition may also affect herbivores via effects on forage availability and quality. We investigated if height-dependent effects of forage and non-forage vegetation determine burrowing extent and activity of arctic ground squirrels (Urocitellus parryii). We collected data on burrow networks and activity of arctic ground squirrels across long-term vegetation monitoring sites in Denali National Park and Preserve, Alaska. The implications of height-specific cover of potential forage and non-forage vegetation on burrowing behaviour and habitat suitability for arctic ground squirrels were investigated using hierarchical Bayesian modelling. Increased cover of forbs was associated with more burrows and burrow systems, and higher activity of systems, for all forb heights. No other potential forage functional group was related to burrow distribution and activity. In contrast, height-dependent negative effects of non-forage vegetation were observed, with cover over 50-cm height negatively affecting the number of burrows, systems and system activity. Our results demonstrate that increases in vegetation productivity have dual, potentially counteracting effects on arctic ground squirrels via changes in forage and vegetation stature. Importantly, increases in tall-growing woody vegetation (shrubs and trees) have clear negative effects, whereas increases in forb should benefit arctic ground squirrels.


Climate change Predation risk Shrub encroachment Shrubification Vegetation structure 



This article is a contribution by the Center for Informatics Research on Complexity in Ecology (CIRCE), funded by the Aarhus University Research Foundation under the AU Ideas program (H. W., J. C. S.), a Murie Science and Learning Research Fellowship from Alaska Geographic (H. W.) and by the Central Alaska Network of the National Park Service (C. R.). J. D. C. was supported by a grant from the Rhineland-Palatinate Ministry of Education, Science, Youth and Culture (The consequences of global change on biological resources, legislation and setting of standards), and by the NoAClim project grant (number 225005) of the Norge Forskningsråd. We thank T. Karels and two anonymous reviewers for helpful comments on the manuscript. We thank L. C. Dempsey, C. Gibson, R. Noel, A. Carlyle and M. Richard for assistance with fieldwork. We thank C. McIntyre and L. Tyrrell for helpful discussions and logistical support.

Supplementary material

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Supplementary material 4 (PDF 583 kb)


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Copyright information

© Springer-Verlag Berlin Heidelberg 2015

Authors and Affiliations

  • H. C. Wheeler
    • 1
  • J. D. Chipperfield
    • 2
    • 3
  • C. Roland
    • 4
  • J.-C. Svenning
    • 1
  1. 1.Department of Biodiversity, Center for Informatics Research on Complexity in Ecology (CIRCE)Aarhus UniversityAarhusDenmark
  2. 2.Ecological and Environmental Change Research Group, Department of BiologyUniversity of BergenBergenNorway
  3. 3.Department of Biogeograph, Fachbereich VIUniversität TrierTrierGermany
  4. 4.National Parks ServiceDenali National Park and PreserveFairbanksUSA

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