Journal of Ornithology

, 148:45 | Cite as

Using the power of comparison to explain habitat use and migration strategies of shorebirds worldwide

  • Theunis Piersma
Original Paper


Shorebirds, or waders, form an ecologically (but not phylogenetically) homogenous group of birds that, despite this homogeneity, exhibits clear correlated contrasts in habitat use and migration distance between closely related species pairs. In addition, within species there is distinct variation in breeding and wintering latitudes, i.e. migration distance. I examine here such contrasts at different taxonomic levels and evaluate what we can learn about selective forces on habitat selection and the evolution of migration strategies in birds. My primary example is the worldwide migration system of the Red Knot Calidris canutus. These sandpipers breed only on high arctic tundra (65–83°N), but they move south from their disjunct, circumpolar breeding areas to nonbreeding sites on the coasts of all continents (except Antarctica), between latitudes 58°N and 53°S. Due to their specialized sensory capabilities, Red Knots generally eat hard-shelled prey found on intertidal, mostly soft, substrates. As a consequence, ecologically suitable coastal sites are few and far between, so they must routinely undertake flights of many thousands of kilometres. In contrast to prediction, Red Knots at tropical intertidal sites have lower fuelling rates than birds at more southern or northern latitudes. This leads to greater time–stress in the southernmost wintering populations that not only have to cover over 14,000 km in single migrations, but also cannot rely on tropical regions to make refuelling stops. Rapid human-caused losses of the food-base in staging areas during both north- and southward migrations have been demonstrated to have caused rapid declines in several Red Knot populations. Detailed worldwide eco-demographic research on these extreme long-distance migrants, as embodied in, for example, the recently established Global Flyway Network, yields a two-pronged benefit: (1) on the basis of the unintended large-scale experiments carried out by humans, we rapidly come to grips with the selection pressures moulding the migration strategies of migrant birds, and (2) in applied contexts, the work gives instantaneous feedbacks on the conservation consequences of man-made alterations to wetland environments at the relevant global spatial scales.


Annual cycle Conservation Flyways Foraging Migration Seasonal schedules Waders 



Giving an IOC plenary is as much a challenge as it is an opportunity, and I am very grateful to the Scientific Programme Committee, especially Jacques Blondel, Susan Hannon, Franz Bairlein and Pat Monaghan, for giving me the chance. I have been extremely fortunate to be able to accumulate considerable experience with several of the world’s shorebirds and their habitats, and I thank Rudi Drent and many others for helping to make this possible. Key financial support came from my parent institutions and through timely grants from the Netherlands Organization for Scientific Research (an NWO-PIONIER research award, NAP and WOTRO grants), the Swedish Academy of Sciences, National Geographic Society, Prins Bernhard Culture Fund and Vogelbescherming-Nederland (BirdLife Netherlands). A worldwide network of dear colleagues, within and outside the international Wader Study Group, keeps me afloat, and for this I thank Allan J. Baker, Patricia M. González, Grant B. Pearson, Hugh Boyd, Phil F. Battley, Danny and Ken Rogers, Bob Gill and Colleen Handel, Åke Lindström, David W. Winkler, Pavel S. Tomkovich, Yaa Ntiamoa-Baidu, Chris Hassell and others. Closer to home I can always rely on Petra de Goeij, Anne Dekinga, Maurine W. Dietz, Bernard Spaans, Maarten Brugge and Jos Hooijmeijer, as well as a wonderful group of PhD students. For prompt comments on the late draft, I thank Danny I. Rogers, Debbie M. Buehler and Chris Hassell. The final figures were prepared in his usual inimitable style by Dick Visser.


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Copyright information

© Dt. Ornithologen-Gesellschaft e.V. 2007

Authors and Affiliations

  1. 1.Animal Ecology Group, Centre for Ecological and Evolutionary StudiesUniversity of GroningenHarenThe Netherlands
  2. 2.Department of Marine Ecology and EvolutionRoyal Netherlands Institute for Sea Research (NIOZ)Den BurgThe Netherlands

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