Gauteng, the smallest of South Africa’s nine provinces, is rich in biodiversity; yet it is also the most densely populated province and thus faces significant development pressures.
A project was therefore initiated in 2001 to identify areas of biodiversity importance in the province, using the systematic spatial biodiversity planning approach that has been adopted in South Africa. This article reports on the final version of the provincial conservation plan as completed in 2011.
Vegetation types and quaternary catchments constituted the coarse filter biodiversity features, while rare and threatened taxa constituted the fine filter features. Ecological processes were captured by a range of landscape features, while planning for climate change primarily involved the design of a corridor network. Planning was undertaken within the ArcView linked C-plan decision support system, where a cost surface preferentially directed the selection of available sites towards low-cost areas.
Forty-four per cent of the province is required to achieve targets. Only 8% of features are close to having their targets met or are adequately conserved in the current protected area network of 23 protected areas covering 2.4% of the province, while 73% of features are absent or poorly represented.
The existing protected area network is inadequate for the conservation of biodiversity in Gauteng. The Gauteng Conservation Plan identifies a set of areas that are required to achieve conservation targets. It is important that identified areas currently not in the protected area network are protected either formally or through legislated land use management processes.
Gauteng is the smallest of South Africa’s nine provinces (
The nine provinces of South Africa.
Despite its small size (approximately 18 178 km²), Gauteng is rich in biodiversity. The province is situated within both the savanna and grassland biomes, with approximately 80% of its area designated as Highveld Grassland, one of the two richest primary grasslands in the world, that is also particularly poorly conserved (< 2% protected) (Low & Rebelo
In the first National Spatial Biodiversity Assessment published for South Africa in 2004 (Driver et al.
In 2001, the former Gauteng Directorate of Nature Conservation (of the then Gauteng Department of Agriculture, Conservation and Environment and now the Biodiversity Management Component of the Department of Agriculture and Rural Development [GDARD]) embarked on a biodiversity planning project for the province that finally culminated in the completion of the Gauteng Conservation Plan Version 3.3 in 2011. The project aimed to identify and map areas important to biodiversity in Gauteng through a spatial biodiversity planning exercise underpinned by explicit representation and persistence goals, and to ultimately provide recommendations and policy strategies for the conservation and management of these areas. It involved the collection and repeated analysis of biodiversity data. The analysis was based on the systematic conservation planning protocol developed by Margules and Pressey (
This article reports on the final version of the provincial conservation plan that was completed in 2011, produced using a statistical approach through the calculation of irreplaceability in the C-plan decision support system (Pressey et al.
Biodiversity is defined as the variety and variability among living organisms and the ecological complexes in which they occur (Scott et al.
Spatial input layers used in the biodiversity planning project for Gauteng, South Africa. Built-up areas are shaded in grey for orientation. (a) Confirmed locations and (b) suitable habitat patches (represented as centroids) of 45 Threatened (IUCN
Provincial conservation targets for species selected as fine filter biodiversity surrogates, developed in accordance with the method set out in Pfab et al. (
Scientific name | Common name | Conservation status | Provincial conservation target and GIS translation thereof |
---|---|---|---|
None | Near Threatened |
Nine locations and 8000 mature individuals = 100% of total area occupied by all confirmed populations (three) plus nine habitat patches |
|
None | Near Threatened |
Three locations and 2600 mature individuals = one habitat patch |
|
Red-hot poker | Endangered (A & B criteria) |
All populations = 100% of total area occupied by all confirmed populations (six) | |
None | Near Threatened |
Two locations and 1800 mature individuals = two habitat patches | |
None | Near Threatened |
Three locations and 3100 mature individuals = three habitat patches | |
None | Rare |
All populations (one) = one habitat patch | |
Climbing green lily/climbing onion/Zulu potato | Vulnerable (A criterion) |
One location and 500 mature individuals = a combination of populations that add up to a population size of 500 | |
None | Vulnerable (B criterion) |
All populations (six) and 10 habitat patches for metapopulation persistence = 100% of total area occupied by one confirmed population plus 15 habitat patches | |
None | Endangered (B criterion) |
All populations (one) and two habitat patches for metapopulation persistence = three habitat patches | |
None | Vulnerable (D criterion) |
All populations (20) and 34 habitat patches for metapopulation persistence = 100% of total area occupied by all confirmed populations (18) plus 36 habitat patches | |
None | Near Threatened |
Two locations and 1500 mature individuals and three habitat patches for metapopulation persistence = five habitat patches |
|
None | Vulnerable (B, C & D criteria) |
All populations and 17 habitat patches for metapopulation persistence = 100% of total area occupied by all confirmed populations (10) plus 17 habitat patches | |
None | Near Threatened |
Four locations and 3400 mature individuals and 19 habitat patches for metapopulation persistence = 100% of total area occupied by all confirmed populations (one) plus 29 habitat patches |
|
None | Vulnerable (D criterion) |
All populations and 39 habitat patches for metapopulation persistence = 100% of total area occupied by all confirmed populations (23) plus 39 habitat patches | |
None | Near Threatened |
Two locations and 1400 mature individuals = 100% of total area occupied by all confirmed populations |
|
None | Vulnerable (B criterion) |
All populations (one) and two habitat patches for metapopulation persistence = three habitat patches | |
None | Vulnerable (D criterion) |
All populations = 100% of total area occupied by all confirmed populations (three) | |
None | Near Threatened |
Ten locations and 8800 mature individuals = 100% of total area occupied by all confirmed populations (19) plus one habitat patch |
|
Endangered (D criterion) |
All populations = 100% of total area occupied by all confirmed populations (one) | ||
None | Endangered (B criterion) |
All populations = 100% of total area occupied by all confirmed populations (four) | |
None | Vulnerable (A criterion) |
One location and 400 mature individuals = one habitat patch | |
Olifant river cycad | Vulnerable (B criterion) |
All populations = 100% of total area occupied by all confirmed populations (four) plus three habitat patches | |
Middelburg cycad | Critically Endangered (A & C criteria) |
All populations = 100% of total area occupied by all confirmed populations (two) | |
None | Vulnerable (B & D criteria) |
All populations (nine) and 15 habitat patches for metapopulation persistence = 24 habitat patches | |
None | Vulnerable (B criterion) |
All populations = 100% of total area occupied by all confirmed populations (five) plus three habitat patches | |
None | Rare |
All populations = 100% of total area occupied by all confirmed populations (one) | |
None | Rare-sparse |
All populations (one) = one habitat patch | |
None | Near Threatened |
Two locations and 1400 mature individuals = 100% of total area occupied by all confirmed populations (one) plus three habitat patches |
|
None | Rare-sparse |
All populations (three) and five habitat patches for metapopulation persistence = eight habitat patches | |
None | Near Threatened |
Four locations and 3200 mature individuals and 10 habitat patches for metapopulation persistence = 100% of total area occupied by all confirmed populations (one) plus 15 habitat patches |
|
None | Near Threatened |
Two locations and 1500 mature individuals and 17 habitat patches for metapopulation persistence = 27 habitat patches |
|
None | Near Threatened |
Two locations and 1900 mature individuals and 31 habitat patches for metapopulation persistence = 100% of total area occupied by all confirmed populations (five) plus 44 habitat patches |
|
None | Endangered (C & D criteria) |
All populations (eight) and 14 habitat patches for metapopulation persistence = 100% of total area occupied by all confirmed populations (five) and 17 habitat patches | |
None | Endangered (A & B criteria) |
All populations (four) and seven habitat patches for metapopulation persistence = 11 habitat patches | |
Tassel orchid | Near Threatened |
Four locations and 3200 mature individuals and 29 habitat patches for metapopulation persistence = 100% of total area occupied by all confirmed populations (11) plus 35 habitat patches |
|
None | Vulnerable (B criterion) |
All populations = 100% of total area occupied by all confirmed populations (11) plus two habitat patches | |
None | Near Threatened |
Three locations and 2500 mature individuals = 100% of total area occupied by all confirmed populations (10) plus one habitat patch | |
None | Near Threatened |
One location and 800 mature individuals = a combination of populations that add up to a population size of 800 | |
None | Endangered (A, B & C criteria) |
All populations = 100% of total area occupied by all confirmed populations (two) plus one habitat patch | |
None | Vulnerable (D criterion) |
All populations = 100% of total area occupied by all confirmed populations (11) plus two habitat patches | |
None | Near Threatened |
Three locations and 2600 mature individuals = 100% of total area occupied by all confirmed populations (three) | |
African almond/bitter almond/bitter almond tree/red stinkwood/wild almond | Vulnerable (A & C criteria) |
All populations (three) = three habitat patches | |
None | Near Threatened |
Eleven locations and 10 000 mature individuals = 100% of total area occupied by all confirmed populations (one) plus eight habitat patches |
|
None | Near Threatened |
Nine locations and 8200 mature individuals and 14 habitat patches for metapopulation persistence = 100% of total area occupied by all confirmed populations (three) plus 19 habitat patches |
|
None | Near Threatened |
Nine locations and 8600 mature individuals and 32 habitat patches for metapopulation persistence = 100% of total area occupied by all confirmed populations (16) plus 35 habitat patches | |
Half-collared Kingfisher | Near Threatened |
Two hundred and forty breeding pairs = 100% of modelled suitable habitat | |
Blue Crane | Vulnerable (A criterion)a,c | Five breeding pairs |
|
African Marsh-harrier | Vulnerable (A & C criteria) |
Ten breeding pairs; 1000 ha per pair = 10 000 ha of modelled suitable habitat | |
Blue Korhaan | Near Threatened |
One hundred breeding pairs;100 ha per pair = 10 000 ha of modelled suitable habitat | |
White-bellied Korhaan | Vulnerable (A & C criteria) |
One hundred and twenty breeding pairs; 120 ha per pair = 14 400 ha of modelled suitable habitat | |
White-backed Night-heron | Vulnerable (A & C criteria) |
Twenty breeding pairs = 100% of modelled suitable habitat | |
Cape Vulture | Vulnerable (A & C criteria)a,c | One breeding population (minimum of 118 breeding pairs) | |
Melodious Lark | Near Threateneda,c | Three hundred and twenty breeding pairs; 2 ha per pair = 640 ha of modelled suitable habitat | |
African Finfoot | Vulnerable (A & C criteria) |
Twenty breeding pairs = 100% of modelled suitable habitat | |
Secretarybird | Near Threatened |
Thirty breeding pairs |
|
African Grass-owl | Vulnerable (A & C criteria) |
One hundred and fifty breeding pairs; 260 ha per pair = 39 000 ha of modelled suitable habitat | |
Roodepoort Copper butterfly | Vulnerable (B criterion) |
One hundred per cent of modelled suitable habitat at known (confirmed) localities for the species | |
Heidelberg Copper butterfly | Vulnerable (B & D criteria) |
One hundred per cent of known localities plus 100% of modelled distribution (inclusive of 70% suitable habitat and 30% of unsuitable habitat for metapopulation persistence) | |
Stobbia’s fruit chafer beetle | Vulnerable (B criterion) |
One hundred per cent of modelled suitable habitat at all known localities | |
Highveld Blue butterfly | Endangered (A & B criteria) |
One hundred per cent of known localities plus 100% of modelled distribution (inclusive of 70% suitable habitat and 30% of unsuitable habitat for metapopulation persistence) | |
Southern African hedgehog | Near Threatened |
One thousand mature individuals at an estimated density of three individuals per hectare = 3000 ha of modelled suitable habitat | |
Spotted-necked otter | Near Threatened |
One hundred and fifty individuals; estimated density of one otter for every 5 km of river = 750 km of river with 100 m rural and 32 m urban buffers | |
Scheiber’s long-fingered bat | Near Threatened |
All known cave roosting sites (10 = one location) (inclusive of a 500 m buffer) | |
Temminck’s hairy bat | Near Threatened |
All known cave roosting sites (three = one location) (inclusive of a 500 m buffer) | |
White-tailed mouse | Endangered (A criterion) |
One viable population of 1000 individuals; one individual per 2 ha = 2000 ha of grassland | |
Juliana’s golden mole | Vulnerable (B criterion) |
One hundred per cent of modelled suitable habitat on the Bronberg | |
Blasius’s/Peak-saddle horseshoe bat | Vulnerable (D criterion) |
All known cave roosting sites (six = one location) (inclusive of a 500 m buffer) | |
Geoffroy’s horseshoe bat | Near Threatened |
All known cave roosting sites (12 = one location) (inclusive of a 500 m buffer) | |
Darling’s horseshoe bat | Near Threatened |
All known cave roosting sites (two = one location) (inclusive of a 500 m buffer) | |
Hildebrandt’s horseshoe bat | Near Threatened |
All known cave roosting sites (one = one location) (inclusive of a 500 m buffer) | |
Mountain catfish | Unique and ecologically sensitive | One hundred per cent of Maloney’s Eye sub-catchment plus three associated streams | |
Lowveld large-scale yellowfish | Unique and ecologically sensitive | One hundred per cent of Maloney’s Eye sub-catchment plus three associated streams | |
Bushveld small-scale yellowfish | Unique and ecologically sensitive | One hundred per cent of Maloney’s Eye sub-catchment plus three associated streams | |
Striped harlequin snake | Near Threatened |
One location/population on Suikerbosrand with an estimated size of 1200 individuals = 100% of modelled suitable habitat |
, Global IUCN assessment.
, Regional IUCN assessment.
, National assessment in accordance with IUCN 2001 criteria.
, Qualifying for global IUCN Red List status.
, Fair dispersers.
, Insufficient remaining habitat known in Gauteng to map feature in accordance with target.
A provincial vegetation map comprising 12 vegetation types (
Within the vegetation types, only primary vegetation (
Conservation targets for the vegetation types of Gauteng, expressed as a percentage of the original extent of a vegetation type and based on the species–area method for setting conservation targets (Desmet & Cowling
Vegetation type | Area of original extent (ha) | Conservation target (%) | Primary vegetation remaining (%) |
---|---|---|---|
Central Sandy Bushveld | 193 187 | 25 | 58 |
Clay Grassland | 30 604 | 8 | 42 |
Gauteng Grassland | 1 046 365 | 21 | 28 |
Loskop Mountain Bushveld | 39 987 | 23 | 93 |
Magaliesberg Mountain Bushveld | 23 822 | 23 | 83 |
Marikana Thornveld | 89 778 | 21 | 36 |
Moot Plains Bushveld | 48 750 | 22 | 44 |
Mountain Bushveld | 180 225 | 24 | 78 |
Norite Koppies Bushveld | 3021 | 27 | 77 |
Rand Highveld Grassland | 143 674 | 19 | 35 |
Springbokvlakte Thornveld | 18 069 | 18 | 44 |
Waterberg-Magaliesberg Summit Sourveld | 350 | 23 | 99 |
Total province | 1 817 832 | - | 40 |
The original extent of each vegetation type is indicated, along with the percentage that currently remains as primary vegetation.
The minimum percentage area required to represent all species within a region is highly variable and depends on the diversity and endemism of the taxa of concern (Rodrigues & Gaston
A total of four quaternary catchments that were deemed to be in a good condition, that is, where the rivers retain a high proportion of their natural or remnant ecological organisation and functions as indicated by River Health PESC scores (Kleynhans & Louw
Conservation targets for good condition quaternary catchments included in the Gauteng Conservation Plan.
Quaternary catchment | Level II Ecoregion | Total area (ha) | PESC score | Conservation target (%) | Area converted to non-natural land cover (%) |
---|---|---|---|---|---|
Elands | Eastern Bankenveld and Bushveld | 68 759 | B | 59 | 4 |
Skeerpoort | Western Bankenveld | 11 051 | B | 59 | 1 |
Upper Suikerbosrant | Highveld | 74 905 | C | 46 | 2 |
Wilge | Eastern Bankenveld and Bushveld | 77 256 | B | 59 | 4 |
Level II Ecoregions (Kleynhans & Louw
Clusters of endorheic pans within the good condition quaternary catchments were mapped as a separate feature (
Ongoing and extensive biodiversity surveys were initiated for Gauteng in 2001 to generate data on the spatial occurrence of plant and animal species. Prior to this, up-to-date information on the biodiversity of the province was severely lacking. The data that existed were associated with sampling bias, were outdated or were captured at too coarse a scale (e.g. quarter degree grids). Surveys for fauna involved passive trapping (using a variety of baited and non-baited traps, cages, nets, etc.), active supplementary searches of suitable habitat and incidental observations. Species occurrence data generated by these surveys were augmented with data sourced from the literature, herbaria, museums, biodiversity databases (e.g. the Coordinated Avifaunal Roadcount [CAR], the Coordinated Waterbird Count [CWAC], the Birds in Reserves Project [BIRP] and the Southern African Butterfly Conservation Assessment [SABCA]), experts and citizen scientists. Confirmed observations of the faunal taxa selected as biodiversity surrogates (
Targeted searches were carried out for the Threatened (Pfab & Victor
Conservation targets for species followed the approach developed by Pfab, Victor and Armstrong (
In this biodiversity planning exercise, landscape features (also termed mesofilters (Hunter
Spatial input layers used in the biodiversity planning project for Gauteng, South Africa. Built-up areas are shaded in grey for orientation. (a) Areas underlain by dolomite; (b) perennial rivers buffered by 100 m if located outside the urban edge (dark blue) and by 32 m if located inside the urban edge (light blue); (c) wetlands and pans (with 30 m buffers if located inside the urban edge and 50 m buffers if located outside the urban edge, and 340 m (Semlitsch & Bodie
To be resilient against climate change, a landscape that allows species to respond to temperature changes and increased weather perturbations and to adapt genetically to changing environments (Opdam & Wascher
Movement of species considered to be fair to good dispersers (Cousins, Lavorel & Davies
As biases in environmental representation can exacerbate the impacts of climate change and habitat loss (Pyke
Carbon sequestration is considered to be important for mitigating anticipated climate warming (Thomas et al.
The inclusion of all wetlands into the conservation plan as an ecological process is anticipated to mitigate the predicted increase in rainfall intensity and extreme flood events.
Data analysis was undertaken within the ArcView linked C-plan decision support system developed by the New South Wales National Parks and Wildlife Services in Australia (Pressey et al.
C-Plan calculates and displays the irreplaceability of each of the sites in a planning region as a guide to their importance for achieving the regional conservation targets. Irreplaceability is defined as the likelihood that a given site will need to be protected to achieve conservation targets. High irreplaceability sites have few or no options for achieving targets and are absolutely necessary if targets are to be achieved. Low irreplaceability values indicate sites with a high degree of flexibility with respect to achieving targets and there are options as to which sites are included in the plan.
The C-plan analysis used a 100 ha hexagonal planning unit to maximise connectivity between adjacent sites. Sites were a priori classified as available or excluded, or as an existing protected area. The following land cover classes were excluded from the analysis: degraded land, non-vegetated/bare land, plantations and woodlots, urban trees, intensive cattle camps, urban areas, mines, sports and recreation grasslands, degraded land associated with smallholdings and non-vegetated/bare/degraded lands associated with old agricultural fields. All protected areas in the province were ground-truthed to confirm their legislative, management and ecological statuses. Only those ecologically intact areas proclaimed in terms of relevant legislation (specifically for the protection of biodiversity or for the purposes of nature conservation) and subject to management plans with a biodiversity focus, as well as those areas either formally proclaimed or subject to management plans, were considered to be part of the protected area network and designated level 1 (a total of 3) and level 2 (a total of 20) protected areas, respectively (
The first step in building the conservation plan involved the selection of all irreplaceable available sites. A cost surface (
Sites required to meet the remaining conservation targets subsequent to the selection of irreplaceable sites were added into the conservation plan using an iterative process. The available sites with the highest biodiversity values (top 5% as indicated by the summed irreplaceability value calculated by the C-plan software) were identified and those located within the lowest cost areas (
The final conservation plan consisted of levels 1 and 2 protected areas, irreplaceable areas and important areas, the latter being those areas required to meet the conservation targets not already achieved in the protected and irreplaceable areas. Through examining contributions to target achievement, the final plan enabled an assessment of the importance of each protected area for biodiversity conservation and the adequacy of the provincial protected area network.
To align the conservation plan with the provisions for bioregional plans in the
All steps in the development of the Gauteng Conservation Plan are depicted in
Flow diagram showing the steps involved in the development of the Gauteng Conservation Plan as described in the methods.
Altogether the conservation plan identified 44% of the land surface area of the province and met all conservation targets efficiently. Critical biodiversity areas (i.e. areas that must be maintained in a good ecological condition (natural or near-natural state) in order to meet conservation targets), including irreplaceable (7.1% of the province), important (16.4% of the province) and protected (2.4% of the province) areas, comprised 26% of the province in the final conservation plan, while an additional 18% of the province constituted ESAs (
The final Gauteng Conservation Plan (Version 3.3 of 2011).
Of the 121 features included in the biodiversity planning exercise, 48 (40%) do not occur within any protected area (
Percentage of conservation target met for the 121 biodiversity features at each successive stage of building the Gauteng Conservation Plan, including the existing protected area network, addition of irreplaceable areas and the final inclusion of important areas.
Percentage of conservation target achieved for each biodiversity feature at each stage of building the Gauteng Conservation Plan.
Biodiversity feature | % conservation target achieved |
||
---|---|---|---|
Existing protected areas | Plus irreplaceable areas | Plus important areas | |
Central Sandy Bushveld | 8 | 35 | 100 |
Clay Grassland | 0 | 373 | 440 |
Gauteng Grassland | 6 | 20 | 100 |
Loskop Mountain Bushveld | 24 | 130 | 221 |
Magaliesberg Mountain Bushveld | 3 | 186 | 209 |
Marikana Thornveld | 12 | 31 | 100 |
Moot Plains Bushveld | < 1 | 75 | 113 |
Mountain Bushveld | 31 | 89 | 168 |
Norite Koppies Bushveld | 98 | 100 | 148 |
Rand Highveld Grassland | 4 | 37 | 101 |
Springbokvlakte Thornveld | 0 | 45 | 125 |
Waterberg-Magaliesberg Summit Sourveld | 0 | 438 | 438 |
Elands Quaternary Catchment | 5 | 44 | 107 |
Skeerpoort Quaternary Catchment | 0 | 75 | 126 |
Upper Suikerbosrant Quaternary Catchment | 0 | 111 | 165 |
Wilge Quaternary Catchment | 8 | 47 | 100 |
Pan cluster PQ catchment | 0 | 100 | 100 |
Pan cluster Priority, good-quality | 0 | 100 | 100 |
0 | 100 | 100 | |
22 | 156 | 300 | |
0 | 100 | 1300 | |
0 | 100 | 100 | |
50 | 100 | 200 | |
33 | 233 | 333 | |
0 | 200 | 300 | |
53 | 100 | 100 | |
22 | 100 | 100 | |
13 | 67 | 220 | |
33 | 100 | 167 | |
6 | 100 | 100 | |
6 | 61 | 181 | |
20 | 80 | 380 | |
0 | 100 | 100 | |
6 | 229 | 565 | |
0 | 100 | 100 | |
14 | 83 | 210 | |
59 | 100 | 100 | |
3 | 44 | 172 | |
0 | 100 | 100 | |
33 | 67 | 267 | |
0 | 100 | 100 | |
6 | 100 | 100 | |
0 | 100 | 100 | |
0 | 100 | 100 | |
0 | 100 | 100 | |
400 | 3000 | 3800 | |
19 | 100 | 100 | |
33 | 300 | 433 | |
62 | 100 | 100 | |
8 | 88 | 192 | |
14 | 100 | 100 | |
0 | 67 | 200 | |
0 | 100 | 100 | |
0 | 400 | 800 | |
0 | 100 | 100 | |
0 | 233 | 333 | |
13 | 113 | 325 | |
98 | 100 | 100 | |
33 | 133 | 293 | |
11 | 78 | 289 | |
0 | 100 | 100 | |
7 | 98 | 250 | |
44 | 100 | 100 | |
18 | 106 | 276 | |
9 | 73 | 191 | |
0 | 100 | 100 | |
14 | 171 | 263 | |
0 | 100 | 100 | |
0 | 50 | 350 | |
0 | 100 | 2900 | |
3 | 100 | 100 | |
4 | 100 | 100 | |
0 | 100 | 100 | |
100 | 100 | 100 | |
0 | 100 | 100 | |
50 | 50 | 150 | |
0 | 100 | 100 | |
0 | 300 | 333 | |
0 | 100 | 100 | |
13 | 113 | 175 | |
0 | 100 | 100 | |
16 | 79 | 342 | |
20 | 100 | 100 | |
17 | 49 | 320 | |
5 | 100 | 100 | |
2 | 9 | 153 | |
0 | 100 | 100 | |
27 | 101 | 209 | |
0 | 98 | 122 | |
57 | 89 | 129 | |
2 | 100 | 100 | |
0 | 100 | 100 | |
1247 | 1488 | 2086 | |
2 | 100 | 100 | |
30 | 74 | 167 | |
66 | 261 | 608 | |
100 | 100 | 100 | |
67 | 100 | 100 | |
297 | 326 | 461 | |
5 | 100 | 100 | |
3 | 100 | 100 | |
0 | 100 | 100 | |
0 | 12 | 178 | |
58 | 102 | 167 | |
12 | 84 | 185 | |
0 | 100 | 100 | |
0 | 100 | 100 | |
148 | 190 | 273 | |
2 | 100 | 100 | |
0 | 100 | 100 | |
0 | 100 | 100 | |
0 | 100 | 100 | |
0 | 100 | 100 | |
0 | 100 | 100 | |
Maloney’s Eye sub-catchment | 0 | 100 | 100 |
92 | 100 | 100 | |
Bioclimatic optimal efficient outside urban edge | 13 | 37 | 104 |
Dinokeng Scarp Woodland | 0 | 100 | 100 |
Magaliesberg Scarp Woodland | 2 | 100 | 100 |
Suikerbosrand Mesic Woodland | 95 | 100 | 100 |
Wilge Scarp Woodland | 9 | 100 | 100 |
% of province | 2 | 14 | 41 |
Number of biodiversity features with targets met | 6 | 89 | 121 |
conf., confirmed population.
Only 10 features (8%) are adequately conserved or are close to having their conservation targets met (> 90% of target achieved) (
The addition of irreplaceable areas in the first step of creating the conservation plan resulted in an almost 10-fold increase in the representation of the province’s biodiversity, such that approximately 76% of the included features would be afforded adequate protection (
Of all the protected areas in the province, the Suikerbosrand Nature Reserve (17 980 ha) and the Rietvlei Dam Nature Reserve (4480 ha) contribute towards meeting conservation targets for the most biodiversity features (32 and 18 biodiversity features, respectively) (
The number of management priorities (biodiversity features for which > 5% of the conservation target is met by the protected area) and the number of biodiversity features occurring within each protected area.
Protected area | Number of biodiversity features | Management priorities |
---|---|---|
Abe Bailey (5083 ha) | 8 | 5 |
Alice Glöckner (155 ha) | 10 | 2 |
De Onderstepoort (2948 ha) | 10 | 6 |
Ezemvelo (2739 ha) | 14 | 8 |
Faerie Glen (127 ha) | 6 | 0 |
Glen Austin (10 ha) | 1 | 0 |
Klipriviersberg (606 ha) | 10 | 3 |
Korsman (45 ha) | 1 | 0 |
Krugersdorp (1351 ha) | 10 | 5 |
Leeuwfontein (2225 ha) | 4 | 2 |
Marievale (1454 ha) | 6 | 2 |
Melville Koppies (42 ha) | 3 | 0 |
Plovers Lake (262 ha) | 10 | 1 |
Rhenosterpoort (906 ha) | 12 | 5 |
Rietvlei Dam (4480 ha) | 18 | 7 |
Rondebult (100 ha) | 2 | 0 |
Roodeplaat Dam (775 ha) | 8 | 1 |
Ruimsig (13 ha) | 2 | 0 |
Suikerbosrand (17 980 ha) | 32 | 25 |
Tswaing (1981 ha) | 4 | 2 |
Voortrekker Monument (259 ha) | 5 | 1 |
Walter Sisulu (286 ha) | 8 | 1 |
Wonderboom (120 ha) | 10 | 3 |
The Gauteng Conservation Plan is a crucial tool for the implementation in Gauteng of the national biodiversity mandate contained within the provisions of NEMBA. The plan identifies areas that are required for the conservation of a representative and sustainable sample of the province’s biodiversity, where converting land uses should be excluded, where land uses incompatible with biodiversity should be avoided and where special management measures are required to maintain and protect biodiversity. Altogether 26% of Gauteng is required for the conservation of the province’s biodiversity, while an additional 18% of the province is important for the continued functioning of the ecological and evolutionary processes that maintain and generate biodiversity – in all 44% of the land surface area. This is well above the oft-posited arbitrary representation targets of 10% or 12%, which may provide effective protection for only half of all terrestrial species (Soulé & Sanjayan
Within the CBAs designated for the province, irreplaceable areas (7.1% of the province) are highly sensitive areas that are essential for the conservation of biodiversity in Gauteng and contribute mainly towards the conservation of Threatened, Near Threatened, rare and other conservation-worthy species of fauna and flora, and also to the conservation of the less extensive (< 40 000 ha) vegetation types in the province, with the exception of Springbokvlakte Thornveld. Irreplaceable areas are also crucial for the conservation of aquatic species within the Upper Suikerbosrant quaternary catchment and the Maloney’s Eye sub-catchment, as well as for biodiversity dependent on good-quality endorheic pans and the pan clusters located within good condition quaternary catchments. As densely wooded areas occurring on steep slopes and in steep ravines are confined to the irreplaceable areas, these areas also play an important role in climate change adaptation.
The important areas (16.4% of the province) within the CBAs are ecologically sensitive areas that contribute mainly towards the conservation of the more extensive vegetation types and species of Threatened and Near Threatened fauna that require extensive areas for their breeding and survival, such as the Blue Crane, Secretary bird and the spotted-necked otter. Important areas also contribute to the metapopulation persistence of many Threatened and conservation-worthy plant taxa as well as to the metapopulation persistence of the Highveld Blue butterfly, and play an especially important role in climate change adaptation through representation of unique bioclimatic classes. To retain the rivers associated with the Elands, Skeerport and Wilge quaternary catchments in good ecological states, the maintenance of vegetative cover through ecologically sensitive land use is required in areas designated as important.
The existing protected area network, covering 2.4% of the land surface area in the province, is inadequate for the conservation of biodiversity in Gauteng. The high level of conversion to other land uses (irreversible habitat loss has affected 21% of the land surface area in Gauteng) and the loss of primary vegetation have resulted in a conservation plan that appears somewhat fragmented in nature, although connectivity is enhanced through the inclusion of a corridor network. Conservation action directed towards the necessary expansion of the current protected area network, either through formal proclamation of protected areas or through stewardship programmes, should focus on large contiguous areas that are also biodiversity hotspots (
The C-plan decision support system can also be used to identify biodiversity features that should be included within a management plan for a protected area, thereby providing the management team with clear management priorities that ensure contribution to a broader conservation strategy. The premier protected areas within Gauteng are clearly the Suikerbosrand Nature Reserve southeast of Johannesburg and the Rietvlei Dam Nature Reserve south of Pretoria. Other important protected areas within the province include the De Onderstepoort, Ezemvelo, Krugersdorp and Rhenosterpoort nature reserves.
Finally, 18.3% of the province is designated as ESAs, which are required for the maintenance and generation of biodiversity in CBAs (i.e. irreplaceable, important and protected areas). ESAs are a crucial part of the conservation plan as they ensure sustainability in the long term.
The Gauteng Conservation Plan is being actively implemented through its incorporation into a number of governmental planning and development tools. It underpins the primary decision support tool for biodiversity assessments in the EIA process that is delegated to provincial government. Together with a standardised set of decision-making guidelines, the plan has allowed for consistent, scientifically justified and defensible recommendations on land development and mining applications. Within the private sector, EIA practitioners rely heavily on the plan when assessing suitability of sites for development. The Gauteng Conservation Plan is also intended to serve as a basis for the gazetting of bioregional plans for municipalities in terms of Section 40 of NEMBA. To date, previous versions of the plan have been used to inform strategic environmental assessments and environmental management frameworks undertaken by GDARD and by other provincial departments in an attempt to avoid sensitive biodiversity areas during, for example, the delineation of the urban edge, the identification of land for low-cost housing and the planning of the future road network. The Gauteng Conservation Plan has also been integrated into the spatial products of local government (such as open space plans and integrated development plans). Nationally, the plan has been instrumental in identifying sensitive geographical areas in terms of the EIA regulations and threatened ecosystems in terms of Section 52 of NEMBA. NEMBA requires that threatened ecosystems be integrated into urban and regional planning, while regulations and biodiversity management plans can also be promulgated for threatened ecosystems. Environmental authorisation is required for any activities that would result in the clearance of indigenous vegetation (area thresholds applicable) within critically endangered or endangered ecosystems, within CBAs in published bioregional plans or within CBAs and ESAs in systematic biodiversity plans such as the Gauteng Conservation Plan.
The Gauteng Conservation Plan Version 3.3 represents a culmination of 10 years of biodiversity planning work in Gauteng, wherein improvements and learning from the collective efforts of the conservation planning community in South Africa were introduced into each version. It is important that provincial conservation efforts now focus on implementation.
This article is dedicated to Pieta Compaan. We thank her for her unending commitment to the Gauteng Conservation Plan project – we could not have done it without her. We would also like to thank the numerous people who have played a role in the success of the project: Coral Birss, Daan Buijs, Siyabonga Buthelezi, Willem Coetzer, Dr Stephen Cornelius, Patrick Duigan, Marianne Forsythe-Coetzee, Andra Hennop, Quinton Joshua, Daniel Koen, Rhulani Kubayi, Vuyokazi Mpumlwana, Sizakele Ndzhukula, Reggy Nkosi, Helen Nonyane, Dr Dean Peinke, Deshni Pillay, Hermien Roux, Earnest Seamark and Dr Sue Taylor. Many thanks and special mention go to the field staff team: Richard Koko, Jacob Makola, Aron Matabane, Wilson Molaba, Job Motsamai and Andries Mphuti. Sandra Turck is thanked for the graphic design of
The authors declare that they have no financial or personal relationships that may have inappropriately influenced them in writing this article.
M.F.P. was the project leader and was also responsible for designing the spatial input layers for plants, vegetation, bioclimatic classes, cost surface, corridor network and the ridges, and ultimately for directing the C-plan analyses to build the Gauteng Conservation Plan. P.C.C. was responsible for all the GIS and C-plan analyses, including preparation of all spatial input layers and building the C-plan database. C.A.W.J., I.E., L.D. and G.M. were responsible for designing the spatial input layers for birds and pans, invertebrates, mammals, and reptiles and amphibians, respectively. L.M. and S.D.W. led the fieldwork teams and contributed significantly to field surveys. P.M. and L.S.N. contributed significantly to designing and preparing the wetland and river layers. S.D.H. conducted the Marxan analysis on the bioclimatic layer, while D.B.H. developed the vegetation map for the province.