Oecologia

, Volume 66, Issue 4, pp 558–562 | Cite as

Central place foraging by beavers (Castor canadensis): a test of foraging predictions and the impact of selective feeding on the growth form of cottonwoods (Populus fremontii)

  • Mark A. McGinley
  • Thomas G. Whitham
Article

Summary

Several predictions of central place foraging theory were tested. As predicted, beavers foraged more selectively at increasing distance from the central place. With increasing distance from the river's edge, beavers cut fewer branches and deleted small branches from their diet. Large branches were favored at all distances, which differs from patterns observed in previous studies of beaver foraging. This difference, however, is expected and supports Schoener's (1979) predictions which are based on differences between provisioning costs and item size.

The selective harvesting of branches predicted by foraging theory affects plant growth form and may influence plant reproductive patterns. High rates of branch removal caused cottonwoods to develop a shrubby architecture. The importance of selective branch choice by beavers on patterns of cottonwood reproduction (i.e., delayed sexual maturity and induced cloning) is discussed.

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References

  1. Andersson M (1978) Optimal foraging area and allocation of search effort. Theor Popul Biol 13:397–409Google Scholar
  2. Andersson M (1981) Central place foraging in the whinchat, Saxicola rubetra. Ecology 62:538–544Google Scholar
  3. Belovsky GE (1984) Summer diet optimization by beaver. Am Mid Nat 111:209–222Google Scholar
  4. Burt WH, Grossenheider RP (1976) A field guide to the mammals. Houghton Mifflin, BostonGoogle Scholar
  5. Davidson DW (1978) Experimental tests of the optimal diet in two social insects. Behav Ecol Sociobiol 4:35–41Google Scholar
  6. Jenkins SH (1980) A size-distance relation in food selection by beavers. Ecology 61:740–746Google Scholar
  7. Jenkins SH, Busher PE (1979) Castor canadensis. Mamm Species 120:1–8Google Scholar
  8. McGinley MA (1984) Central place foraging for nonfood items: determination of the stick size-value relationship of house building materials collected by eastern woodrats. Am Nat 123:841–853Google Scholar
  9. Orians GH, Pearson NE (1979) On the theory of central place foraging. In: Horn DH, Mitchell R, Stairs GR (eds) Analysis of ecological systems. Ohio State University Press, Columbus, pp 155–177Google Scholar
  10. Pinkowski B (1983) Foraging behavior of beavers (Castor canadensis) in North Dakota. J Mammal 64:312–314Google Scholar
  11. Pyke GH (1984) Optimal foraging theory: a critical review. Ann Rev Ecol Syst 15:523–575Google Scholar
  12. Schoener TW (1979) Generality of the size-distance relation in models of optimal feeding. Am Nat 114:902–914Google Scholar
  13. Whitham TG, Mopper S (1985) Chronic herbivory: impacts on tree architecture and sex expression of pinyon pine. Science (in press)Google Scholar
  14. Whitham TG, Williams AG, Robinson AM (1984) The variation principle: individual plants as temporal and spatial mosaics of resistance to rapidly evolving pests. In: Price PW, Slobodchikoff CN, Gaud WS (eds) A new ecology: novel approaches to interactive systems. Wiley, New York, pp 15–51Google Scholar

Copyright information

© Springer-Verlag 1985

Authors and Affiliations

  • Mark A. McGinley
    • 1
  • Thomas G. Whitham
    • 2
    • 3
  1. 1.Department of BiologyUniversity of UtahSalt Lake CityUSA
  2. 2.Department of Biological SciencesNorthern Arizona UniversityFlagstaffUSA
  3. 3.Biology DepartmentMuseum of Northern ArizonaFlagstaffUSA

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