, Volume 95, Issue 2, pp 164–170 | Cite as

Feeding-patch choice by red deer in relation to foraging efficiency

An experiment
  • Rolf Langvatn
  • Thomas A. Hanley
Original Papers


We tested the idea that ruminants allocate their feeding time to habitat patches in relation to foraging efficiency. We used five tame red deer (Cervus elaphus) in an enclosure planted with four treatment of timothy grass (Phleum pratense) differing in their stage of growth. Older swards offered higher biomass but lower nutritional quality than younger swards. We observed time spent feeding in each treatment during each of seven trials. We measured goodness-of-fit between observed times and predictions from two alternative hypotheses differing in optimization strategy (maximizing versus matching), and a third, null hypothesis. We tested the hypotheses using two alternative currecies: digestible protein, and digestible dry matter or energy. Although digestible protein concentration and dry-matter digestibility were highly correlated (r=0.763, P<0.001), the wider range of digestible protein made it the much more sensitive measure of forage quality. Distributions of feeding time closely matched estimated intake rates of digestible protein (RinfPredsup2=0.899) across all animals and trials. The other hypotheses were rejected. The results have important ecological implications in showing the underlying role of food in the selection of habitat by ruminants, and that simple, mechanistic models of forage intake and digestion can be scaled up to the level of animal behavioural choices.

Key words

Herbivore-plant interactions Foraging ecology Habitat selection Ruminants Cervus elaphus 


  1. Albon SD, Langvatn R (1992) Plant phenology and the benefits of migration in a temperate ungulate. Oikos 65:502–513Google Scholar
  2. Bunnell FL, Gillingham MP (1985) Foraging behavior: dynamics of dining out. In: Hudson RJ, White RG (eds) Bioenergetics of wild herbivores. CRC Press, Boca Raton, Fla, pp 53–79Google Scholar
  3. Casella G (1983) Leverage and regression through the origin. Am Stat 37:147–152Google Scholar
  4. Fox JL (1991) Forage quality of Carex macrochaeta emerging from Alaskan alpine snowbanks through the summer. Am Midl Nat 126:287–293Google Scholar
  5. Goering HR, Van Soest PJ (1970) Forage fiber analysis. United States Department of Agriculture, Agricultural Research Service, Agricultural Handbook no. 379Google Scholar
  6. Gordon IJ (1989a) Vegetation community selection by ungulates on the Isle of Rhum. II. Vegetation community selection. J Appl Ecol 26:53–64Google Scholar
  7. Gordon IJ (1989b) Vegetation community selection by ungulates on the Isle of Rhum. III. Determinants of vegetation community selection. J Appl Ecol 26:65–79Google Scholar
  8. Hanley TA (1984) Habitat patches and their selection by wapiti and black-tailed deer in a coastal montane coniferous forest. J Appl Ecol 21:423–436Google Scholar
  9. Hanley TA, Robbins CT, Hagerman AE, McArthur C (1992) Predicting digestible protein and digestible dry matter in tannin-containing forages consumed by ruminants. Ecology 73:537–541Google Scholar
  10. Herrnstein RJ (1970) On the law of effect. J Exp Anal Behav 13:243–266Google Scholar
  11. Illius AW, Wood-Gush DGM, Eddison JC (1987) A study of the foraging behaviour of cattle grazing patchy swards. Biol Behav 12:33–44Google Scholar
  12. Illius AW, Clark DA, Hodgson J (1992) Discrimination and patch choice by sheep grazing grass-clover swards. J Anim Ecol 61:183–194Google Scholar
  13. Kamil AC, Roitblat HL (1985) The ecology of foraging behavior: implications for animal learning and memory. Annu Rev Psychol 36:141–169Google Scholar
  14. Klein DR (1965) Ecology of deer range in Alaska. Ecol Monogr 35:259–284Google Scholar
  15. Langvatn R, Albon SD (1986) Geographic clines in body weight of Norweigan red deer: a novel explanation of Bergmann's rule? Holarctic Ecol 9:285–293Google Scholar
  16. MacArthur RH, Pianka ER (1966) On optimal use of a patchy environment. Am Nat 100:603–609Google Scholar
  17. Morgantini LE, Hudson RJ (1989) Nutritional significance of wapiti (Cervus elaphus) migrations to alpine ranges in western Alberta, Canada. Arct Alp Res 21:288–295Google Scholar
  18. Mould ED, Robbins CT (1981a) Nitrogen metabolism in elk. J Wildl Manage 45:323–334Google Scholar
  19. Mould ED, Robbins CT (1981b) Evaluation of detergent analysis in estimating nutritional value of browse. J Wildl Manage 45:937–947Google Scholar
  20. Mould ED, Robbins CT (1982) Digestive capabilities in elk compared to white-tailed deer. J Wildl Manage 46:22–29Google Scholar
  21. Myers RH (1986) Classical and modern regression with applications. Duxbury Press, Boston, MassGoogle Scholar
  22. Robbins CT (1983) Wildlife feeding and nutrition. Academic Press, New YorkGoogle Scholar
  23. Saeboe B (1982) A population-genetic study of spiked grass with emphasis on content of silicon (in Norwegian). Norges landbruksvitenskaplige forskningsråd, NLVF, Report no. 412, 16 ppGoogle Scholar
  24. Stephens DW, Krebs JR (1986) Foraging theory. Princeton University Press, Princeton, NJGoogle Scholar
  25. Van Soest PJ (1982) Nutritional ecology of the ruminant. O and B Books, Corvallis, OreGoogle Scholar
  26. Westoby M (1974) Analysis of diet selection by large generalist herbivores. Am Nat 108:290–304Google Scholar
  27. Westoby M (1978) What are the biological bases of varied diets? Am Nat 112:627–631Google Scholar
  28. White RG (1983) Foraging patterns and their multiplier effects on productivity of northern ungulates. Oikos 40:377–384Google Scholar
  29. Wickstrom ML, Robbins CT, Hanley TA, Spalinger DE, Parish SM (1984) Food intake and foraging energetics of elk and mule deer. Wildl Manage 48:1285–1301Google Scholar
  30. Wilm HG, Costello DF, Klipple GE (1944) Estimating forage yield by the double sampling method. J Am Soc Agron 36:194–203Google Scholar

Copyright information

© Springer-Verlag 1993

Authors and Affiliations

  • Rolf Langvatn
    • 1
  • Thomas A. Hanley
    • 2
  1. 1.Norwegian Institute for Nature ResearchTrondheimNorway
  2. 2.Pacific Northwest Research Station, Forestry Sciences LaboratoryUSDA Forest ServiceJuneauUSA

Personalised recommendations