Evolutionary Ecology

, Volume 2, Issue 3, pp 189–196 | Cite as

The American Avocet (Recurvirostra americana) as a paradigm for adult automimicry

  • Tex A. Sordahl


The body of theory concerning life-history strategies predicts that the duration of high-mortality stages should be minimized by natural selection. This is especially applicable to the avian pre-flight stage, during which growth rates typically are rapid. Using the American Avocet (Recurvirostra americana) as a paradigm, I propose a developmental strategy by which young animals can lower their mortality rates by an accelerated (and deceptive) acquisition of adult or adult-like characters. The benefit accrues when predators misidentify the vulnerable young as adults and fail to attack them because adults are much less vulnerable. This strategy, termed adult automimicry, is most likely to occur in precocial species living in open habitats.

American Avocets are large, precocial, open-country shorebirds that first fly when about 4–5 weeks old. They develop a juvenal, plumage in their third week that resembles adult breeding plumage in pattern and color, even though plumage details are different. At this time chicks begin using adult foraging techniques and tend to move away rather than hide from potential predators. A few weeks later they acquire a first winter plumage that resembles adult winter plumage. Thus, avocet chicks appear unusually adult-like after their second week. This should make it difficult for distant predators to distinguish flightless chicks from volant adults.


Adult automimicry automimicry mimicry life-history strategies antipredator adaptations American Avocet Recurvirostra americana 


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. Baker, R. R. and Parker, G. A. (1979) The evolution of bird coloration.Philos. Trans. R. Soc. Lond. (B) 287, 63–130.Google Scholar
  2. Bent, A. C. (1927). Life histories of North American shorebirds. Part I.U.S. National Museum Bulletin 142, 1–420.Google Scholar
  3. Brower, L. P. (1969) Ecological chemistry.Sci. Amer. 220(2) 22–9.Google Scholar
  4. Cott, H. B. (1940).Adaptive Coloration in Animals. Oxford University Press, New York, NY, USA.Google Scholar
  5. Curio, E. (1976).The Ethology of Predation, Springer Verlag, New York, NY, USA.Google Scholar
  6. Fjeldså, J. (1977)Guide to the Young of European Precocial Birds. Skarv, Strandgarden, Denmark.Google Scholar
  7. Gibson, F. (1971) The breeding biology of the American Avocet (Recurvirostra americana) in central Oregon.Condor 73, 444–54.Google Scholar
  8. Hailman, J. P. (1977)Optical Signals: Animal Communication and Light. Indiana University Press, Bloomington, IN, USA.Google Scholar
  9. Hamilton, R. B. (1975) Comparative behavior of the American Avocet and the Black-necked Stilt (Recurvirostridae).Ornith. Monog.,17, 1–98.Google Scholar
  10. Kushlan, J. A. (1977). The significance of plumage colour in the formation of feeding aggregations of ciconiiforms.Ibis 119, 361–4.Google Scholar
  11. Makkink, G. F. (1936) An attempt at an ethogram of the European Avocet (Recurvirostra avosetta L.), with ethological and psychological remarks.Ardea 25, 1–62.Google Scholar
  12. Norman, D. O. (1977) A role for plumage color in Mute Swan (Cygnus olor) parent-offspring interactions.Behaviour 62, 314–21.Google Scholar
  13. Palmer, R. S. (1967) Plumage descriptions and species accounts. InThe Shorebirds of North America. (G. D. Stout, ed.), Viking Press, New York, NY. USA.Google Scholar
  14. Paulson, D. R. (1973). Predator polymorphism and apostatic selection.Evolution 27, 269–77.Google Scholar
  15. Porter, R. D. and White, C. M. (1973) The Peregrine Falcon in Utah, emphasizing ecology and competition with the Prairic Falcon.Brigham Young Univ. Sci. Bull. Biol. Ser. 18 1–74.Google Scholar
  16. Prater, A. J., Marchant, J. H., and Vuorinen, J. (1977) Guide to the identification and ageing of Holarctic waders.British Trust Ornith. Field Guide 17, 1–168.Google Scholar
  17. Procter-Gray, E., and Holmes, R. T. (1981) Adaptive significance of delayed attainment of plumage in male American Redstarts: tests of two hypotheses.Evolution 35, 742–51.Google Scholar
  18. Ricklefs, R. E. (1973) Patterns of growth in birds. II. Growth rate and mode of development.Ibis 115, 177–201.Google Scholar
  19. Rohwer, S., Fretwell, S. D. and Niles, D. M. (1980) Delayed maturation in passerine plumages and the deceptive acquisition of resources.Amer. Natur. 115, 400–37.Google Scholar
  20. Sordahl, T. A. (1981) Phenology and status of the shorebirds in northern Utah.Western Birds 12, 173–80Google Scholar
  21. Sordahl, T. A. (1982) Antipredator behavior of American Avocet and Black-necked Stilt chicks.J. Field Ornith. 53, 315–25.Google Scholar
  22. Sordahl, T. A. (1984) Observations on breeding site fidelity and pair formation in American Avocets and Black-necked Stilts.North American Bird Bander 9(2), 8–11.Google Scholar
  23. Sordahl, T. A. (1986) Evolutionary aspects of avian distraction display: variation in American Avocet and Black-necked Stilt antipredator behavior. InDeception: Perspectives on Human and Nonhuman Deceit (R. W. Mitchell and N. S. Thompson, eds.) pp. 87–112, State University of New York Press, Albany, NY, USA.Google Scholar
  24. Steenhof, K., Kochert, M. N. and Doremus, J. H. (1983) Nesting of subadult Golden Eagles in southwestern Idaho.Auk 100, 743–7.Google Scholar
  25. Turner, E. L. (1921) The avocet at home.British Birds 14, 194–202.Google Scholar
  26. Vane-Wright, R. I. (1976) A unified classification of mimetic resemblances.Biol. J. Linn. Soc. 8, 25–56.Google Scholar
  27. Waldbauer, G. P., Sternburg, J. G. and Maier, C. T. (1977) Phenological relationships of wasps, bumblebees, their mimics, and insectivorous brids in an Illinois sand area.Ecology 58, 583–91.Google Scholar
  28. Watson, D. (1977)The Hen Harrier T. & A. D. Poyser, Berkhamsted, UK.Google Scholar
  29. Wickler, W. (1968)Mimicry in Plants and Animals, McGraw-Hill, New York, NY, USA.Google Scholar
  30. Williams, G. C. (1966)Adaptation and Natural Selection: A Critique of Some Current Evolutionary Thought. Princeton University Press, Princeton, NJ, USA.Google Scholar

Copyright information

© Chapman and Hall Ltd. 1988

Authors and Affiliations

  • Tex A. Sordahl
    • 1
  1. 1.Department of BiologyLuther CollegeDecorahUSA

Personalised recommendations