Journal of Ornithology

, Volume 152, Supplement 1, pp 49–66 | Cite as

Isotopic ornithology: a perspective

  • Keith A. HobsonEmail author


The use of measurements of naturally occurring stable isotopes of the light elements C, N, H, O, S in avian tissues and their associated foodwebs has grown tremendously during the last 30 years. Three primary applications of this approach have been (1) the delineation of diets or trophic relationships and sources of nutrients to individuals or populations, (2) the assessment of the relative contributions of endogenously and exogenously derived nutrients to reproduction in birds that travel to breed, and, more recently, (3) the assignment to origin of migratory individuals. This paper will briefly summarize the roots of these theme areas and highlight the benefits of an isotope perspective. However, the primary focus of this paper is on key assumptions, misunderstandings, information gaps and the path ahead. Specific recommendations for future research are outlined for all of these theme areas. Finally, a plea is made for more constructive criticism in the field of isotopic applications to animal ecological studies, especially those involving birds.


Stable isotopes Migratory connectivity Diet Reproductive investment Isoscapes 



I thank Franz Bairlein and Peter Becker for their kind invitation to present this work as part of the centenary celebration of their Institute for Ornithology. Ideas presented here have been formed through constructive discussion over the years with several colleagues and include Len Wassenaar, Peter Marra, Mike Wunder, Steve Van Wilgenburg, Anders Møller, Tibor Szèp, Carlos Martinez del Rio, Gabe Bowen, Blair Wolf, Ryan Norris and Stuart Bearhop. Ryan Norris and an anonymous reviewer provided helpful comments on an earlier draft of this paper.


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Copyright information

© Dt. Ornithologen-Gesellschaft e.V. 2011

Authors and Affiliations

  1. 1.Environment CanadaSaskatoonCanada

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