Conservation of the invertebrate fauna on the Cape Peninsula
Thesis (PhD (Conservation Ecology and Entomology))--Stellenbosch University, 2008.
The Cape Peninsula is an area of outstanding biological importance, having 158 endemic angiosperm species in only 470 km2. The peninsula invertebrates are known to be highly endemic, yet very little else is known about them. This study has four components: (1) ascertaining whether the influence of environmental variables on epigaeic, foliage and aerial invertebrate assemblages of Table Mountain, (2) determinination of the influence of Table Mountain’s fires and land transformation, on the local invertebrate assemblage, (3), identification of areas of conservation priority and influential environmental variables across the entire Cape Peninsula, and (4) determinination whether invertebrate food availability is a restricting factor for the localised and threatened Knysna warbler (Bradypterus sylvaticus), which inhabits the forests on the east side of Table Mountain. Epigaeic, foliage and aerial invertebrates were intensively sampled using a suite of techniques. Sites were chosen to allow for comparisons between vegetation structure and type, elevation and aspect. Vegetation structure and elevation were the most important environmental variables in determining species composition. Fynbos had a higher beta diversity of epigaeic and aerial invertebrates than forests, so the conservation of as much fynbos as possible is needed. The forests had many unique and endemic species, highlighting their conservation importance. As elevation had a strong influence, yet only the higher elevations receive extensive conservation, it is critical to conserve as much of the disturbed and fragmented lower elevations as soon as possible. There was little correlation between the diversity of aerial and epigaeic‐foliage invertebrate assemblages. Thus, the aerial and epigaeic‐foliage invertebrate assemblages need to be assessed separately.