Biodiversity and Conservation

, Volume 17, Issue 1, pp 53–69

Land rehabilitation and the conservation of birds in a degraded Afromontane landscape in northern Ethiopia

  • Raf Aerts
  • Frederik Lerouge
  • Eva November
  • Luc Lens
  • Martin Hermy
  • Bart Muys
Original Paper

Abstract

The few remaining Afromontane forest fragments in northern Ethiopia and the surrounding degraded, semiarid matrix form a habitat mosaic of varying suitability for forest birds. To evaluate the effect of recent land rehabilitation efforts on bird community composition and diversity, we studied bird species distributions in ten small forest fragments (0.40–20.95 ha), five grazing exclosures (10-year-old forest restoration areas without wood extraction and grazing livestock) and three grazed matrix sites during the rainy season (July–October 2004) using 277 one-hour species counts. Based on the distribution pattern of 146 bird species, sites were assigned to one of three bird communities (birds of moist forest, dry forest or degraded savanna), each occupying a well-defined position along an environmental gradient reflecting decreasing vegetation structure and density. All three communities were representative of the avifauna of Afrotropical Highland open forest and woodland with a high proportion of invasive and competitive generalist species (31%). Apart from these, exclosures shared more species with forest fragments (20%) than did the grazed matrix (5%), indicating local ecosystem recovery. By increasing habitat heterogeneity, exclosures have the potential to enhance landscape connectivity for forest birds and are, therefore, an effective instrument for conserving species in a fragmented landscape. However, 52 bird species (36%) occurred exclusively within forest patches and many forest birds that use exclosures are unlikely to maintain viable populations when forest fragments disappear, particularly as forest fragments may be a critical resource during the hot dry season. This highlights the high conservation value of small isolated forest fragments for less tolerant, forest-limited and/or biome-restricted species.

Keywords

Avian species diversity Ethiopia Exclosures Forest fragments Fragmentation Matrix habitat Protected area management Semiarid Small patches Restoration 

Abbreviations

TSC

Timed species count

MRPP

Multiresponse permutation procedure

NMDS

Non-metric multidimensional scaling

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Copyright information

© Springer Science+Business Media B.V. 2007

Authors and Affiliations

  • Raf Aerts
    • 1
  • Frederik Lerouge
    • 1
  • Eva November
    • 2
  • Luc Lens
    • 3
  • Martin Hermy
    • 1
  • Bart Muys
    • 1
  1. 1.Division Forest, Nature and LandscapeKatholieke Universiteit LeuvenLeuvenBelgium
  2. 2.Royal Museum for Central AfricaTervurenBelgium
  3. 3.Terrestrial Ecology UnitGhent UniversityGentBelgium

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