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Oecologia

, Volume 140, Issue 2, pp 295–301 | Cite as

Do floral syndromes predict specialization in plant pollination systems? An experimental test in an “ornithophilous” African Protea

  • Anna L. Hargreaves
  • Steven D. JohnsonEmail author
  • Erica Nol
Plant Animal Interactions

Abstract

We investigated whether the “ornithophilous” floral syndrome exhibited in an African sugarbush, Protea roupelliae  (Proteaceae), reflects ecological specialization for bird-pollination. A breeding system experiment established that the species is self-compatible, but dependent on visits by pollinators for seed set. The cup-shaped inflorescences were visited by a wide range of insect and bird species; however inflorescences from which birds, but not insects, were excluded by wire cages set few seeds relative to open-pollinated controls. One species, the malachite sunbird (Nectarinia famosa), accounted for more than 80% of all birds captured in P. roupelliae  stands and carried the largest protea pollen loads. A single visit by this sunbird species was enough to increase seed set considerably over unvisited, bagged inflorescences. Our results show that P. roupelliae is largely dependent on birds for pollination, and thus confirm the utility of floral syndromes for generating hypotheses about the ecology of pollination systems.

Keywords

Floral syndrome Ornithophily Pollen-limitation Pollination efficiency Proteaceae 

Notes

Acknowledgements

We are grateful to Mark Brown for help with mist netting and banding, Mike Lawes, Jeff Ollerton and a further anonymous reviewer for comments on the manuscript, Greg Anderson for assisting with the UV microscopy techniques, and Mondi Forests for conserving Mt Gilboa and allowing us access to it. Special thanks to Sandy Steenhuisen for her help both in the field and out.

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Copyright information

© Springer-Verlag 2004

Authors and Affiliations

  • Anna L. Hargreaves
    • 2
  • Steven D. Johnson
    • 1
    Email author
  • Erica Nol
    • 2
  1. 1.School of Botany and ZoologyUniversity of KwaZulu-NatalScottsvilleSouth Africa
  2. 2.Biology DepartmentTrent UniversityPeterboroughCanada

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