The ecological effectiveness of protected areas: a case study for South African birds

Authors

  • M. Greve,

    1. Department of Botany and Zoology, Centre for Invasion Biology, Stellenbosch University, Matieland, South Africa
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    • *Current address: Ecoinformatics & Biodiversity Group, Department of Biological Sciences, Aarhus University, Aarhus-C, Denmark.

  • S. L. Chown,

    1. Department of Botany and Zoology, Centre for Invasion Biology, Stellenbosch University, Matieland, South Africa
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  • B. J. van Rensburg,

    1. Department of Zoology and Entomology, Centre for Invasion Biology, University of Pretoria, Pretoria, South Africa
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  • M. Dallimer,

    1. Biodiversity and Macroecology Group, Department of Animal and Plant Sciences, University of Sheffield, Sheffield, UK
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  • K. J. Gaston

    1. Biodiversity and Macroecology Group, Department of Animal and Plant Sciences, University of Sheffield, Sheffield, UK
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  • Editor: Res Altwegg

  • Associate Editor: Nick Isaac

Correspondence
Kevin J. Gaston, Biodiversity and Macroecology Group, Department of Animal and Plant Sciences, University of Sheffield, Sheffield S10 2TN, UK Tel: 0 114 222 0030; Fax: 0 114 222 0002
Email: k.j.gaston@sheffield.ac.uk

Abstract

While the importance of individual protected areas (PAs) to biological conservation is widely acknowledged, rather few empirical studies have explicitly attempted to assess their ecological effectiveness. Significantly, this includes consideration of how well they represent the biodiversity of taxonomic groups for which the designation of these areas was not a primary or intentional goal. Here, we provide one of the most detailed comparisons to date of the avian biodiversity found inside and outside PAs, focusing on three PAs distributed widely across South Africa. Typically, bird assemblages were richer, with a higher density, and a different structural and functional composition inside than outside the PAs. Importantly, insectivore richness was much higher inside than outside, and the converse was true of granivores. Overall, these findings suggest that PAs do indeed provide valuable repositories for native biodiversity, with species richness, density and species composition being substantially different beyond their bounds. With human land-use increasing in South Africa, and habitat transformation recognized as a major and growing threat to biodiversity, such differences are expected to become greater.

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