Historically, the Cape Flats area was characterised by numerous seasonal wetlands and vleis. Through the unavoidable process of urbanisation many of these wetlands have been drained or filled in to create areas for this development. The wetlands that remain are of remarkable importance as they are islands of ecological significance and break the monotony of the urban environment. These remaining areas are a refuge for wildlife, flora and a venue for recreation and relaxation.
Zandvlei is situated in the south western corner of the densely populated Cape Flats. The public are exposed to marine,
estuarine, freshwater and Strandveld ecosystems all within the immediate area. Zandvlei is unique when compared to the majority of these wetlands, as it is an estuary. An estuary is that portion of a river system that has, or can have interaction with the sea. Animals found in both
freshwater and marine environments are present in estuaries. This leads to a high number of species being found in this type of habitat and Zandvlei is a fine example. Many of the 28 recorded species are dependant on
estuaries for their survival. The juveniles of the se marine fish enter the estuaries shortly after spawning and
remain until they reach maturity.
Zandvlei Nature Reserve is situated in the northern part of the estuary
and comprises 22ha of diverse habitats. Biotic elements include 169 plant species of which 8 are classified red data, 5 amphibian species including the endangered Leopard Toad, 18 mammals and 18 reptile species. Since 1998 we have recorded 150 bird species within the reserve of which 7 are classified red data , including the Eastern White Pelican, Peregrine Falcon and Greater and Lesser Flamingo. Red data species are defined as those threatened with extinction.
The Westlake Wetlands form the upper western reaches of the estuary. Here the salinity is very low and most of this area can be considered to be a fresh water system.
Three rivers flow from the 64km2 catchment into the estuary ; Sand, Keysers, and Westlake.
The estuary also plays an important role as a venue for recreation. Sports such as wind surfing canoeing, sailing and angling can all be enjoyed at Zandvlei. The ecological health of the system must be protected and enhanced as an
ecologically sound system that can benefit all user groups. Sound natural resource and user group management will ensure better functioning of the estuary in the long term.
Adele Pretorius. Student