Behavioral Ecology and Sociobiology

, Volume 8, Issue 1, pp 35–40 | Cite as

Optimal foraging and territorial defence in the Great Tit (Parus major)

  • Alejandro Kacelnik
  • Alasdair I. Houston
  • John R. Krebs


We describe an experiment designed to investigate the trade-off between foraging and territorial vigilance in the Great Tit. Captive territorial male Great Tits were observed while foraging in a large indoor aviary. They obtained food from two operant ‘patches’ in which the supply of food was gradually depleted during a visit. We predicted that during control sessions the birds would switch between patches in such a way as to maximise their overall feeding rate. In experimental sessions, we introduced briefly a rival male as an ‘intruder’ at the start of the test. The foraging male could see the rival only when travelling between patches and not while feeding within patches. We predicted that during experimental sessions birds would switch between patches more often than in control tests, sacrificing food intake for territorial vigilance. Three of the four males tested behaved in approximately the predicted manner. We discuss the use of an inverse optimality argument to provide a calibration of feeding against the benefit resulting from territorial vigilance.


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. Belovsky GE (1978) Diet optimization in a generalist herbivore: the moose. Theor Popul Biol 14:105–134Google Scholar
  2. Blurton-Jones NG (1978) Observations and experiments on causation of threat displays of the great tit (Parus major). Anim Behav Monogr 1:74–78Google Scholar
  3. Charnov EL (1976) Optimal foraging: the marginal value theorem. Theor Popul Biol 9:129–136Google Scholar
  4. Charnov EL, Orians G, Hyatt K (1976) Ecological implications of resource depression. Am Nat 110:247–259Google Scholar
  5. Cowie RJ (1977) Optimal foraging in great tits (Parus major). Nature 268:137–139Google Scholar
  6. King JR (1974) Seasonal allocation of time and energy resources in birds. In: Paynter RA (ed) Avian energetics. Nuttal Ornithological Club, Cambridge, MAGoogle Scholar
  7. McFarland DJ (1977) Decision making in animals. Nature 269:15–21Google Scholar
  8. Milinski M, Heller R (1978) Influence of a predator on the optimal foraging behaviour of sticklebacks (Gasterosteus aculeatus L.). Nature 275:642–644Google Scholar
  9. Parker GA, Stuart RA (1976) Animal behaviour as a strategy optimizer: evolution of resource assessment strategies and optimal emigration thresholds. Am Nat 110:1055–1076Google Scholar
  10. Pyke E, Pulliam HR, Charnov EL (1977) Optimal foraging: a selective review of theory and tests. Q Rev. Biol 52:137–154Google Scholar

Copyright information

© Springer-Verlag 1981

Authors and Affiliations

  • Alejandro Kacelnik
    • 1
  • Alasdair I. Houston
    • 1
  • John R. Krebs
    • 2
  1. 1.Animal Behaviour Research Group, Department of ZoologyUniversity of OxfordOxfordUK
  2. 2.Edward Grey Institute of Field Ornithology, Department of ZoologyUniversity of OxfordOxfordUK

Personalised recommendations