The Critical Biodiversity Areas (CBA) map for the Garden Route aims to guide sustainable development by providing a synthesis of biodiversity information to decision makers. It serves as the common reference for all multi-sectoral planning procedures, advising which areas can be lost to development, and which areas of critical biodiversity value and their support zones should be protected against any impacts.
The CBA map indicates areas of land as well as aquatic features which must be safeguarded in their natural state if biodiversity is to persist and ecosystems are to continue functioning. Land in this category is referred to as a Critical Biodiversity Area. CBAs incorporate: (i) areas that need to be safeguarded in order to meet national biodiversity thresholds (ii) areas required to ensure the continued existence and functioning of species and ecosystems, including the delivery of ecosystem services; and/or (iii) important locations for biodiversity features or rare species.
Ecological Support Areas (ESAs) are supporting zones required to prevent the degradation of Critical Biodiversity Areas and Protected Areas. An ESA may be an ecological process area that connects and therefore sustains Critical Biodiversity Areas or a terrestrial feature, e.g. the riparian habitat surrounding and supporting aquatic Critical Biodiversity Areas.
Those areas of natural vegetation identified on the map as Other Natural Areas are sufficiently extensive at this stage that they may withstand some loss through conversion of their natural state, and undergo development. It is important to note that in the future, such areas will be increasingly converted or impacted, and it is possible that they will eventually be reclassified as Critical Biodiversity Areas. Therefore, in all decision making, the precautionary principle needs to be applied.
The CBA map identifies areas that have been irreversibly transformed through development (e.g. urban development, plantation, agriculture). These areas are referred to as No Natural Areas Remaining. They no longer contribute to the biodiversity of the area. However, there are areas of land (partially or wholly transformed or degraded land) that have been classified as ESAs or even CBAs. Although these areas are heavily degraded or transformed, they still play an important role in supporting ecological processes.
Note: The biodiversity criteria used to define the CBAs and the land-use guidelines for each category on the CBA map may be found in The Garden Route Sector Plans or the Garden Route Mapbook.
Limitations of the CBA map
The spatial accuracy of the information presented is inherently limited by the accuracy of the biodiversity databases used to develop the map. Mapping accuracy varies from approximately 1:5 000 through to about 1:10 000 scale. More importantly the information content of the CBA map is limited by the depth of knowledge on the distribution of biodiversity in the district captured in electronic databases. The majority of information used to define CBAs represent broad scale surrogates for biodiversity pattern and process as there are few observation based (e.g. point locality species datasets) or fine-scale (e.g. 1:50 000 scale vegetation maps) biodiversity datasets available for the district.
