Thesis (MScConsEcol (Conservation Ecology and Entomology))--University of Stellenbosch, 2009. / Habitat loss and fragmentation are two of the most pressing threats to biodiversity. Avifaunal
diversity and integrity is under immense pressure from these two processes. We have made
major advances in our understanding of avifaunal responses to habitat fragmentation, but mostly
focus on either fragment scale and/or landscape scale influences of fragmentation on birds. A
more comprehensive approach to assessing the impacts of fragmentation was used in this study.
The avifaunas of two different geographical regions and bioregions were surveyed and a multiscale
analysis of avifaunal responses to fragmentation was attempted. The study sites include the
West Coast and East Coast Renosterveld Bioregions in the Cape Floristic Region, South Africa.
Assemblage shifts, feeding guild compositional changes, species abundance variation and species
persistence were examined at the three spatial scales. Time- and distance-restricted point counts
were used to document birds that were directly dependent on the habitat fragments. Forty
fragments were selected in each bioregion and a once-off snapshot of the avifaunal richness and
diversity was obtained.
Results indicate that the avifauna of the two bioregions responded differently to habitat
fragmentation. In the East Coast Renosterveld Bioregion, the assemblages, guild composition
and species abundances were most accurately predicted by landscape configuration. An
assemblage shift occurred at 20 ha fragment area, compared to the 50 ha fragment area threshold
of the West Coast Renosterveld Bioregion’s avifauna composition. In the West Coast
Renosterveld Bioregion, fragment area was the better predictor of assemblage, guild composition
and species abundances. However in both bioregions, the persistence of common species was
equally sensitive to area and landscape scale effects.
| Identifer | oai:union.ndltd.org:netd.ac.za/oai:union.ndltd.org:sun/oai:scholar.sun.ac.za:10019.1/1627 |
| Date | 03 1900 |
| Creators | Kieck, Marius Burger |
| Contributors | Krug, Cornelia B., Lloyd, Penn, Samways, Michael J., University of Stellenbosch. Faculty of Agrisciences. Dept. of Conservation Ecology and Entomology. |
| Publisher | Stellenbosch : University of Stellenbosch |
| Source Sets | South African National ETD Portal |
| Language | English |
| Detected Language | English |
| Type | Thesis |
| Rights | University of Stellenbosch |
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