, Volume 152, Issue 2, pp 377–387 | Cite as

Multiscale wolf predation risk for elk: does migration reduce risk?

  • Mark HebblewhiteEmail author
  • Evelyn H. Merrill
Behavioral Ecology


While migration is hypothesized to reduce predation risk for ungulates, there have been few direct empirical tests of this hypothesis. Furthermore, few studies examined multiscale predation risk avoidance by migrant ungulates, yet recent research reveals that predator–prey interactions occur at multiple scales. We test the predation risk reduction hypothesis at two spatial scales in a partially migratory elk (Cervus elaphus) population by comparing exposure of migrant and resident elk to wolf (Canis lupus) predation risk. We used GPS and VHF telemetry data collected from 67 migrant and 44 resident elk over the summers of 2002–2004 in and adjacent to Banff National Park (BNP), Canada. We used wolf GPS and VHF telemetry data to estimate predation risk as a function of the relative probability of wolf occurrence weighted by a spatial density model that adjusted for varying pack sizes. We validated the predation risk model using independent data on wolf-killed elk, and showed that combining wolf presence and spatial density best predicted where an elk was likely to be killed. Predation risk on summer ranges of migrant elk was reduced by 70% compared to within resident elk summer ranges. Because wolves avoided areas near high human activity, however, fine-scale selection by resident elk for areas near high human activity reduced their predation risk exposure to only 15% higher than migrants, a difference significant in only one of three summers. Finally, during actual migration, elk were exposed to 1.7 times more predation risk than residents, even though migration was rapid. Our results support the hypothesis that large-scale migrations can reduce predation. However, we also show that where small-scale spatial variation in predation risk exists, nonmigratory elk may equally reduce predation risk as effectively as migrants under some circumstances.


Antipredator behavior Human–wildlife relationships Partial migration Predator avoidance Resource selection 



Funding was provided by the Alberta Conservation Association, Alberta Cooperative Conservation Research Unit, Alberta Enhanced Career Development, Alberta Sustainable Resource Development, the Canon National Parks Science Scholarship for the Americas (MH), Centre for Mathematical Biology, Challenge Grants in Biodiversity, Foothills Model Forest, Foundation for North American Wild Sheep, Marmot, Mountain Equipment Co-op Environment Fund, National Sciences and Engineering Research Council (NSERC) CRO grant # 261091-02, Parks Canada, Patagonia, Rocky Mountain Elk Foundation, Sundre Forest Products Limited, Weyerhauser Inc., and the University of Alberta. We thank the staff and biologists of the Ya Ha Tinda ranch, Parks Canada, and Alberta Fish and Wildlife. For animal capture services, we thank T. Shury (DVM) and C. Wilson and T. Vandenbrink, and M. Dupuis for fixed-wing telemetry monitoring. We thank the numerous field assistants for invaluable help during this study, especially C. Mueller, L. Thurston, H. Spaedtke, and H. Keta. Finally, we thank H. Beyer, S. Boutin, C. Cassady-St. Clair, J. Frair, C. Gates, C. Jerde, F. Messier, L. Morgantini, M. Musiani, D. Simader, and C. White for helpful discussion and reviews of past drafts of this manuscript. All research was conducted in accordance with, and obtained authorization from, appropriate University, Provincial and Federal legislation and policies.


  1. Anderson DP, Turner MG, Forester JD, Zhu J, Boyce MS, Beyer H, Stowell L (2005) Scale-dependent summer resource selection by reintroduced elk in Wisconsin, USA. J Wildl Manage 69:298–310CrossRefGoogle Scholar
  2. Baltagi BH, Wu PX (1999) Unequally spaced panel data regressions with AR (1) disturbances. Econom Theory 15:814–823CrossRefGoogle Scholar
  3. Bergerud AT, Butler HE, Miller DR (1984) Antipredator tactics of calving caribou—dispersion in mountains. Can J Zool 62:1566–1575CrossRefGoogle Scholar
  4. Beyer H (2005) Hawthtools analysis tools for ArcGIS. H. Beyer, Edmonton, AB, Canada. Accessed January 21, 2007.
  5. Beyer H (2006) Wolves, elk, and willow on Yellowstone’s northern range. University of Alberta, Edmonton, AB, CanadaGoogle Scholar
  6. Boyce MS, Vernier PR, Nielsen SE, Schmiegelow FKA (2002) Evaluating resource selection functions. Ecol Modell 157:281–300Google Scholar
  7. Caro TM (2005) Antipredator defenses in birds and mammals. University of Chicago Press, Chicago, ILGoogle Scholar
  8. Craighead JJ, Atwell G, O’Gara BW (1972) Elk migration in and near Yellowstone National Park. Wildl Monogr 29:1–52Google Scholar
  9. Dussault C, Ouellet J-P, Coutois R, Huot J, Breton L, Jolicoeur H (2005) Linking moose habitat selection to limiting factors. Ecography 28:1–10CrossRefGoogle Scholar
  10. Fortin D, Beyer HL, Boyce MS, Smith DW, Duchesne T, Mao JS (2005) Wolves influence elk movements: behavior shapes a trophic cascade in Yellowstone National Park. Ecology 86:1320–1330Google Scholar
  11. Frair JL, Merrill EH, Allen JR, Boyce MS (2007) Know thy enemy: experience affects translocation success in risky landscapes. J Wildl Manage (in press)Google Scholar
  12. Fretwell SD (1972) Populations in a seasonal environment. Princeton University Press, Princeton, NJGoogle Scholar
  13. Frid A, Dill L (2002) Human-caused disturbance stimuli as a form of predation risk. Conserv Ecol 6:11Google Scholar
  14. Fryxell JM, Greever J, Sinclair ARE (1988) Why are migratory ungulates so abundant? Am Nat 131:781–798CrossRefGoogle Scholar
  15. Geist V (2002) Adaptive behavioral strategies. In: Toweilli DE, Thomas JW (eds) Elk of North America—ecology and management. Stackpole Books, Harrisburg, PA, pp 219–277Google Scholar
  16. Gillies C, Hebblewhite M, Nielsen SE, Krawchuk M, Aldridge C, Frair J, Stevens C, Saher DJ, Jerde C (2006) Application of random effects to the study of resource selection by animals. J Anim Ecol 15:887–898CrossRefGoogle Scholar
  17. Girard I, Ouellet JP, Courtois R, Dussault C, Breton L (2002) Effects of sampling effort based on GPS telemetry on home-range size estimations. J Wildl Manage 66:1290–1300CrossRefGoogle Scholar
  18. Gude JA, Garrott RA, Borkowski JJ, King F (2006) Prey risk allocation in a grazing ecosystem. Ecol Appl 16:285–298PubMedGoogle Scholar
  19. Hamilton WD (1971) Geometry for the selfish herd. J Theor Ecol 31:295–311Google Scholar
  20. Hebblewhite M (2006) Linking predation risk and forage to ungulate population dynamics. University of Alberta, Edmonton, AB, CanadaGoogle Scholar
  21. Hebblewhite M, Paquet PC, Pletscher DH, Lessard RB, Callaghan CJ (2004) Development and application of a ratio-estimator to estimate wolf killing rates and variance in a multiple prey system. Wildl Soc Bull 31:933–946Google Scholar
  22. Hebblewhite M, White CA, Nietvelt C, McKenzie JM, Hurd TE, Fryxell JM, Bayley S, Paquet PC (2005a) Human activity mediates a trophic cascade caused by wolves. Ecology 86:2135–2144Google Scholar
  23. Hebblewhite M, Merrill EH, McDonald TE (2005b) Spatial decomposition of predation risk using resource selection functions: an example in a wolf–elk system. Oikos 111:101–111Google Scholar
  24. Hebblewhite M, Merrill EH, Morgantini LE, White CA, Allen JR, Bruns E, Thurston L, Hurd TE (2006) Is the migratory behaviour of montane elk herds in peril? The case of Alberta’s Ya Ha Tinda elk herd. Wildl Soc Bull 34(5):1280–1294Google Scholar
  25. Hemson G, Johnson P, South A, Kenward R, Ripley R, MacDonald D (2005) Are kernels the mustard? Data from global positioning system (GPS) collars suggest problems for kernel home-range analyses with least-squares cross-validation. J Anim Ecol 74:455–463CrossRefGoogle Scholar
  26. Holland WD, Coen GM (1983) Ecological (biophysical) land classification of Banff and Jasper National Parks; vol. 1: Summary. Alberta Institute of Pedology, Edmonton, AB, CanadaGoogle Scholar
  27. Houston AE, McNamara JM, Hutchinson JMC (1993) General results concerning the trade-off between gaining energy and avoiding predation. Philos Trans R Soc Lond B 341:375–397CrossRefGoogle Scholar
  28. Jevons S (2001) Human use digital atlas of the Canadian Central Rockies ecosystem. Miisitakis Institute for the Rockies & Geoworks GIS, Canmore, AB, CanadaGoogle Scholar
  29. Johnson CJ, Parker KL, Heard DC, Gillingham MP (2002a) A multi-scale behavioral approach to understanding the movements of woodland caribou. Ecol Appl 12:1840–1860CrossRefGoogle Scholar
  30. Johnson CJ, Parker KL, Heard DC, Gillingham MP (2002b) Movement parameters of ungulates and scale-specific responses to the environment. J Anim Ecol 71:225–235CrossRefGoogle Scholar
  31. Kaartinen S, Kojola I, Colpaert A (2005) Finnish wolves avoid roads and settlements. Ann Zool Fenn 42:523–532Google Scholar
  32. Kjellander P, Gaillard JM, Hewison M, Liberg O (2004) Predation risk and longevity influence variation in fitness of female roe deer (Capreolus capreolus L.). Proc Royal Soc B Biol Sci 271:S338–S340Google Scholar
  33. Kristan WBI, Boarman WI (2003) Spatial pattern of risk of common raven predation on desert tortoises. Ecology 84:2432–2443Google Scholar
  34. Kunkel K, Pletscher DH (2001) Winter hunting patterns of wolves in and near Glacier National Park, Montana. J Wildl Manage 65:520–230CrossRefGoogle Scholar
  35. Lank DB, Butler RW, Ireland J, Ydenberg RC (2003) Effects of predation danger on migration strategies of sandpipers. Oikos 103:303–320CrossRefGoogle Scholar
  36. Lewis MA, Murray JD (1993) Modeling territoriality and wolf deer interactions. Nature 366:738–740CrossRefGoogle Scholar
  37. Lima SL, Zollner PA (1996) Towards a behavioral ecology of ecological landscapes. Trends Ecol Evol 11:131–135CrossRefGoogle Scholar
  38. Manly BFJ, McDonald LL, Thomas DL, McDonald TL, Erickson WP (2002) Resource selection by animals: statistical analysis and design for field studies, 2nd edn. Kluwer, Boston, MAGoogle Scholar
  39. Mao JS, Boyce MS, Smith DW, Singer FJ, Vales DJ, Vore JM, Merrill EH (2005) Habitat selection by elk before and after wolf reintroduction in Yellowstone National Park. J Wildl Manage 69:1691–1707CrossRefGoogle Scholar
  40. Mech LD, Boitani L (2003) Wolves. Behavior, ecology, and conservation. University of Chicago Press, Chicago, ILGoogle Scholar
  41. Morgantini LE, Hudson RJ (1988) Migratory patterns of the wapiti, Cervus elaphus, in Banff National Park, Alberta. Can Field Nat 102:12–19Google Scholar
  42. Mysterud A, Ims RA (1998) Functional responses in habitat use: availability influences relative use in trade-off situations. Ecology 79:1435–1441CrossRefGoogle Scholar
  43. Nelson ME, Mech LD (1991) Wolf predation risk associated with white-tailed deer movements. Can J Zool 69:2696–2699Google Scholar
  44. Rettie WJ, Messier F (2000) Hierarchical habitat selection by woodland caribou: its relationship to limiting factors. Ecography 23:466–478CrossRefGoogle Scholar
  45. Rosenberg DK, McKelvey KS (1999) Estimation of habitat selection for central-place foraging animals. J Wildl Manage 63:1028–1038Google Scholar
  46. Schmaljohann H, Dierschke V (2005) Optimal bird migration and predation risk: a field experiment with northern wheatears Oenanthe oenanthe. J Anim Ecol 74:131–138CrossRefGoogle Scholar
  47. Skrondal A, Rabe-Hesketh S (2004) Generalized latent variable modeling: multilevel, longitudinal, and structural equation models. Chapman and Hall, New YorkGoogle Scholar
  48. StataCorp (2003) Stata Statistical Software: Release 8.0. Stata Corporation, College Station, TXGoogle Scholar
  49. Theuerkauf J, Jedrzejewski W, Schmidt K, Gula R (2003) Spatiotemporal segregation of wolves from humans in the Bialowieza Forest (Poland). J Wildl Manage 67:706–716CrossRefGoogle Scholar
  50. Thurber JM, Peterson RO, Drummer TD, Thomasma TA (1994) Gray wolf response to refuge boundaries and roads in Alaska. Wildl Soc Bull 22:61–68Google Scholar
  51. Vaughan IP, Ormerod SJ (2005) The continuing challenges of testing species distribution models. J Appl Ecol 42:730–742Google Scholar
  52. Whittington J, St.Clair CC, Mercer EG (2005) Spatial responses of wolves to roads and trails in Jasper National Park. Ecol Appl 15:543–553Google Scholar
  53. Worton BJ (1989) Kernel methods for estimating the utilization distribution in home-range studies. Ecology 70:164–168CrossRefGoogle Scholar

Copyright information

© Springer-Verlag 2007

Authors and Affiliations

  1. 1.Wildlife Biology Program, Department of Ecosystem and Conservation Sciences, College of ForestryUniversity of MontanaMissoulaUSA
  2. 2.Department of Biological SciencesUniversity of AlbertaEdmontonCanada

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