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Fourth Country Report

to the United Nations Convention on Biological Diversity

Sample Chapter I from South Africa:



Overview of biodiversity status, trends and threats

Produced by



South African National Biodiversity Institute

December 2007







PLEASE NOTE:

This sample chapter was produced on the request of the CBD Secretariat as an example of the layout of the chapter. The data in this chapter was the most up-to-date data available at the time of drafting of this report, but it should nevertheless not be read as an official submission to the CBD Secretariat but rather as an example using currently available data. This sample chapter should not be quoted and may change in South Africa’s Fourth National Report to the CBD.


Contents of Chapter 1





Contents of Chapter 1 i

List of Tables ii

List of Figures ii

1.1 Introduction 1

1.2 The overall picture 1

1.3 Terrestrial biodiversity 6

1.4 Freshwater biodiversity 11

1.5 Estuarine biodiversity 12

1.6 Marine biodiversity 15

1.7 Implications of biodiversity loss 17

References 21



List of Tables





Table 1: Species richness within South African taxa in relation to the world (adapted from Rouget et al. 2004) 2

Table 2: Percentage of the country covered by various land cover classes according to 1994 and 2000 National Land Cover maps 8

Table 3 Percentage of river length of main river ecosystems in each ecological state class. 12

Table 4 Ecosystem status of estuarine groups as in the National Spatial Biodiversity Assessment 2004 13

Table 5 Percentage of estuaries in each ecosystem health class as determined by the South African National Spatial Biodiversity Assessment 2004 14




List of Figures





Figure 1: Map of biomes and global biodiversity hotspots of South Africa 3

Figure 2: Map of ecosystem status of terrestrial ecosystems in South Africa, as assessed in the National Spatial Biodiversity Assessment 2004 7

Figure 3: Protection levels of terrestrial biomes in South Africa 8

Figure 4: Threats affecting Red Data Listed plant species in South Africa 9

Figure 5 : Cumulative total number of GMOs that have been approved for general release in South Africa 10

Figure 6: Area in hectares planted under GMO crops in South Africa 11

Figure 7: Map of ecosystem status of main river ecosystems in South Africa, as assessed in the National Spatial Biodiversity Assessment 2004 11

Figure 8: Map of ecosystem status of marine biozones in South Africa, as assessed in the National Spatial Biodiversity Assessment 2004 16





1.1 Introduction

This chapter provides an overview of South Africa’s biodiversity status and trends, and threats to biodiversity. The aim is not to be comprehensive but rather to highlight information to inform decision-makers.


The chapter is structured as follows:

  • Section 1.2 gives a brief overall picture of biodiversity status, trends and threats in South Africa

  • Section 1.3 deals with biodiversity status, trends and threats in the terrestrial environment

  • Section 1.4 deals with the freshwater environment

  • Section 1.5 deals with the estuarine environment

  • Section 1.6 deals with the marine environment

  • Section 1.7 deals with the implications for human wellbeing

South Africa is in the process of developing a National Biodiversity Monitoring & Reporting Framework. Where possible, headline indicators from this framework have been included in the chapter. In most cases it is not possible to give time series comparisons as these do not exist at present. As part of the development of the National Biodiversity Monitoring & Reporting Framework South Africa is in the process of collecting time series data for many of these indicators, so time series will be available in the future.



1.2 The overall picture




1.2.1 South Africa’s unique biodiversity

South Africa is situated on the southernmost tip of the African continent, spanning the area from latitude 22ºS to 35ºS, and from longitude 17ºE to 33ºE (Lombard et al. 2004). It covers a total land surface area of 1 219 090 km2 and its Exclusive Economic Zone in the oceans off its coastline covers an area of 1 071 883 km2 (SANBI 2007b). It is an exceptionally biodiverse country which also has a high level of socio-cultural diversity and a rapidly growing semi-developed economy.


South Africa occupies only 2% of the world’s land surface area and yet is home to 10% of the world’s plant species and 7% of the reptile, bird and mammal species. Its oceans are home to about 10 000 species, representing almost 15% of the world’s marine species (DEAT 2006). Table 1 gives information on the number of described species in each taxonomic group in South Africa as well as the percentage of globally described species that this represents (Rouget et al. 2004, SANBI 2007b).
Table 1: Species richness within South African taxa in relation to the world (adapted from Rouget et al. 2004)

Taxon

Number of described species in SA

% of the earth’s species

Mammals

227

5.8

Birds

718

8

Amphibians

84

2.1

Reptiles

286

4.6

Freshwater

112

1.3

Marine fish

2 150

16

Invertebrate

77 500

5.5

Plants

23 420

10

As shown in Table 1, South Africa is home to over 23 000 plant species. More than half of these are endemic to South Africa. The vegetation of the Southern African region has an exceptionally high species-area ratio of 0.0081 species per km2, compared with a ratio of 0.0044 species per km2 for Brazil and 0.0041 species per km2 for Asian countries. The faunal diversity of South Africa is also high relative to the country’s surface area (Rouget et al. 2004).


The terrestrial biodiversity of South Africa can be divided into nine biomes: Albany thicket, desert, forest, fynbos, grassland, Indian Ocean coastal belt, Nama karoo, savanna and succulent Karoo (Mucina & Rutherford 2006).
There are three globally recognised biodiversity hotspots in South Africa: the Cape Floristic Region; the Succulent Karoo, shared with Namibia; and the Maputaland-Pondoland-Albany hotspot, shared with Mozambique and Swaziland. Figure 1 shows the location of the biomes and biodiversity hotspots of South Africa (Rouget et al. 2004).
INSERT FIGURE 1

Figure 1: Map of biomes and global biodiversity hotspots of South Africa


South Africa is also home to an entire floral kingdom which occurs nowhere else in the world, the Cape Floral Kingdom. The Kingdom is located mostly in South Africa’s Western Cape Province and is the smallest, richest and most threatened of the world’s six floral kingdoms. It is home to 9 000 plant species, or 38% of the country’s plant species, of which 1 850 (over 20%) are threatened with extinction (Rouget et al. 2004, DEAT 2006).
South Africa’s Exclusive Economic Zone covers parts of the Atlantic, Indian and Southern Oceans and includes the areas surrounding the sub-Antarctic islands that form part of the country’s territories. The marine environment in South Africa is unusual in that it has two different currents, the cold Benguela current on the western coast and the warm Aghulas current on the eastern coast. South Africa’s oceans are home to a wide variety of habitats from kelp forests through coral reefs to rocky shores (Lombard et al. 2004).
South Africa has 259 estuaries which are sparsely distributed along the arid west coast and increase in density towards the east. These estuaries can be grouped into subtropical, warm temperate and cool temperate estuaries. Subtropical estuaries have the highest biodiversity (Turpie et al. 2004).

1.2.2 Pressures on South Africa’s biodiversity

Much of the unique biodiversity of South Africa is heavily threatened by human activities. The major pressures affecting South African biodiversity are outlined below (SANBI 2007b). In this section the general nature of the pressures is outlined with no quantitative information. In the subsequent sections on terrestrial, freshwater, estuarine and marine biodiversity specific quantitative information will be provided on the pressures relevant to each of these environments.



Habitat loss


Many areas of natural habitat are permanently destroyed by activities as diverse as urban housing developments, clearing for cultivation of crops or forestry plantations, canalisation of rivers and trawling of sea beds. As areas of habitat are destroyed, the areas available for inhabitation by various species and ecosystem types is reduced and some species or ecosystems may fall below a threshold where they are viable and hence become extinct.

Habitat degradation


There are many areas of natural habitat which, although not permanently destroyed, are in sub-optimal condition owing to a variety of causes including overexploitation, overgrazing and poor management practices. Degraded habitat cannot support the same diversity of species as intact habitat. The Southern African Millennium Ecosystem Assessment highlighted the expansion of degraded areas into currently undegraded areas under sustainable management as the most immediate threat to biodiversity (DEAT 2006).

Invasive alien species


Invasive alien species are non-native species which have been introduced by human activities and which now propagate and spread independently in the country. Such species often invade and replace indigenous vegetation and species, thus causing a loss of biodiversity.

Flow modification


South Africa is a water scarce country and many of the economic activities in the country are limited by the availability of water. Thus, the country’s rivers are heavily utilised and dammed. This results in an alteration in both the volume of water flowing as well as the seasonality of water flows into rivers, estuaries and eventually the oceans. In some cases flows are also increased by the discharge of effluents or treated sewage. Many rivers that used to vary in flow throughout the year now flow evenly throughout the year, and others have times of no flow or very low flow which they did not experience previously. The opening and closing of estuary mouths is also affected, thus altering the delicate balance between salt and freshwater inflows into estuaries. Much of the biodiversity in aquatic ecosystems is adapted to certain conditions and regimes of flow and when these are altered the habitats are no longer optimal for them to flourish in.
In South Africa water is also transferred artificially between catchments (inter-basin transfers) to make more water available in areas where demand is high. This also alters natural flow regimes as well as introducing new species to catchments where they did not previously occur which can have negative effects on other species native to the catchment.

Harvesting


A wide variety of South African species play a vital role in our economy and are used for purposes such as medicines, food sources, building materials and exotic ornamental plants or pets. All of these uses involve extraction or harvesting of the species from the environment. If harvesting is not kept to low enough levels it can have a detrimental effect on the species, reducing populations faster than they can be naturally replaced. Over-harvesting of Marine Living Resources is the largest threat to the marine environment in South Africa and many highly overexploited species are still consumed on a large scale (Lombard et al. 2004). In the terrestrial environment, a large but as yet unknown number of species of medicinal plants are over harvested (DEAT 2006).

Climate change


The change in climatic conditions being experienced across the globe as a result of the increased concentration of greenhouse gases in the atmosphere since the industrial revolution also affects biodiversity. South Africa’s climate is predicted to change such that the distributions of many of its species and ecosystems will move eastwards as the western parts of the country become drier and the Eastern parts wetter. In the contemporary fragmented landscape it is problematic for species to move as fragments of natural habitat are sparse and disjointed. Climate change also causes changes in the temperature and alkalinity of aquatic systems affecting the survival of biodiversity (DEAT 2006, SANBI 2007b).

Pollution


The discharge of industrial effluents into our water systems as well as the runoff from agricultural lands and urban settlements, bringing with it the chemicals leached from these areas, pollute water systems and have a detrimental effect on biodiversity. High nutrient contents caused by fertilisers or other nutrients reaching aquatic ecosystems result in eutrophication where the system becomes anaerobic and there is not enough oxygen for many species to survive. Many toxic substances also have detrimental effects on biodiversity.

Genetically Modified Organisms


Genetically Modified Organisms (GMOs) are organisms that are modified in a laboratory to have characteristics derived from genes of other species. Under South African legislation, GMOs have to be thoroughly tested before they are released as agricultural crops into the open environment. There is a concern that GMOs can have a detrimental effect on biodiversity by cross-pollinating with indigenous species or by being viable in areas that non-GMO crops are not thus resulting in additional widespread loss of natural habitat. Many GMOs are bred to be resistant to herbicides, which raises the concern that herbicide usage will increase, thus increasing pollution levels. However, these species allow cultivation practices with less tillage thus lowering soil erosion and leaching risks. Some GMOs have in-built resistance to pests, resulting in a lower usage of pesticides which can have a positive impact on biodiversity (SANBI 2007b).

Hybridisation


Hybridisation between two closely related indigenous species, or between two subspecies or geographic forms of a single species, can result in the loss of unique genetic diversity found in the unhybridised individuals. This is especially problematic when organisms are transported by human activities to areas where they would not usually occur or away from their area of origin. Game ranching and mariculture both result in such transportation.

1.3 Terrestrial biodiversity




1.3.1 Status of terrestrial biodiversity

National Red List assessments of the status of South Africa’s species indicated that 10% of South Africa’s birds and frogs, 20% of its mammals and 9% of its plants are threatened. Analyses show that for species of fauna, no particular biome in South Africa contains more threatened species than any other. For plants, however, the fynbos biome has a much higher number of threatened species than any other (DEAT 2006).


South Africa’s first National Spatial Biodiversity Assessment (NSBA) was conducted in 2004 (Driver et al. 2005). Assessments of the 427 vegetation types of South Africa showed that 5% of them are critically endangered, 12% are endangered and 16% are vulnerable. The largest proportion of the threatened vegetation types occur in the fynbos biome which is part of the Cape Floristic Region, a global biodiversity hotspot. Figure 2 shows the location of the various categories of threatened vegetation types in South Africa (Diver et al. 2005).
INSERT FIGURE 2

Figure 2: Map of ecosystem status of terrestrial ecosystems in South Africa, as assessed in the National Spatial Biodiversity Assessment 2004


South Africa has produced two National Land Cover (NLC) maps, based on 1994 and 2000 data respectively. Table 2 shows the percentage of the country covered by various land cover classes in these two years. According to these figures, cultivated areas and forestry plantations cover a smaller percentage of the country in 2000 than they did in 1994, whilst natural areas have a larger coverage in 2000. This is counter-intuitive as it is not possible for there to be more natural areas in 2000 than in 1994 unless large tracts of land have been rehabilitated, which is not the case. This observed trend is due to the fact that the two land cover maps were constructed on different scales and using different methodologies, resulting in their outputs not being easily comparable. There are, for example, large tracts of land that were classified as transformed (not natural) in 1994 which were classified as natural in 2000. There are also problems that have been identified with the accuracy of the data on these maps. This lack of comparability between land cover maps is a serious challenge for biodiversity monitoring in the country. South Africa is working towards regularly updated land cover maps that are comparable with one another (SANBI 2007b).
The area under forestry plantations is drastically reduced from 7.6% in 1994 to 1.4% in 2000. This is not necessarily due to an actual reduction but rather due to differences in how forests were identified in the construction of the two maps which would result in areas of dense invasion by alien trees being classified either as plantations or as natural vegetation. It is also possible that some forestry plantations were misclassified as natural vegetation or vice versa.
Table 2: Percentage of the country covered by various land cover classes according to 1994 and 2000 National Land Cover maps

Land cover class

% of country according to

NLC 1994

% of country according to NLC 2000

Cultivated areas

11.6

10.9

Forestry plantations

7.6

1.4

Industrial areas

0.1

0.1

Mines

0.1

0.2

Natural areas

79.7

86.3

Urban areas

0.9

1.2

Currently, just over 6% of the country’s surface area is included in protected areas, composed of 479 Type I protected areas and 471 Type 2 protected areas. Type I protected areas are those that are formally protected, including national parks, provincial conservation areas, municipal protected areas and forest nature reserves. Type 2 protected areas are less formally protected and include mountain catchment areas, state forests, defence force property, natural heritage sites, wildlife management areas, private nature reserves, bird sanctuaries and botanical gardens. Few of the protected areas are larger than 100 000 hectares, and most are between 1 000 and 10 000 hectares. The protected area network does not protect all biomes equally. Figure 3 shows the protection levels of the different biomes. The most poorly protected biomes are the wetland, grassland, succulent karoo and Nama karoo biomes (DEAT 2006).


INSERT FIGURE 3

Figure 3: Protection levels of terrestrial biomes in South Africa



1.3.2 Threats to terrestrial biodiversity

South Africa is a developing country and thus many of its economic sectors are growing rapidly, resulting in extensive loss of natural habitat. Urban expansion is threatening natural vegetation especially in the grasslands and fynbos biomes. Agricultural cultivation has also resulted in the loss of much natural habitat with the area under cultivation having trebled in the last 50 years and the area under forestry plantations having increased ten fold (DEAT 2006). Although plantations cover a relatively small percentage of the country, they are located in key catchment areas and have a proportionally large impact on the country’s biodiversity.


As noted above, even if natural habitat is not completely transformed or destroyed, it is often degraded into sub-optimal states. Large portions of South Africa are under cattle or game ranching and are thus still basically natural. However, if these areas are allowed to degrade through unsustainable management, they will no longer support the biodiversity they originally sustained. The area of land under ranching is much greater than that under conservation management and thus this offers a major opportunity for improved biodiversity management.
The country’s plant species are heavily threatened by a variety of threats, the most serious of which are habitat loss and agriculture. Habitat loss is caused extensively by clearing of natural vegetation for the construction of housing or other urban developments. These urban developments tend to be concentrated in certain areas and thus although they may only cover a relatively small area, they heavily impact on the flora in the areas where they are concentrated. Figure 4 shows a breakdown of the severity of the threats facing Red Listed plant species in South Africa (SANBI 2007a).
INSERT FIGURE 4

Figure 4: Threats affecting Red Data Listed plant species in South Africa


Ten million hectares of land, or 8% of the land in South Africa, is currently infested by about 200 species of invasive alien plants across all biomes and ecosystems. The invasive alien plants have a negative impact on the biodiversity and the economy of the country. It is estimated that it will cost R12 billion (R600 million per year for 20 years) to clear all the invasive alien species currently within the country (DEAT 2006).
Many of South Africa’s species are threatened by extractive use (harvesting), especially for medicinal purposes. An estimated 20 000 tonnes of plant material is traded annually and the value to the economy is estimated at R270 million. Many of the more popular species are overexploited and their populations are declining rapidly in the wild. Efforts are now underway to increase the commercial cultivation of such species to supplement the supply from wild populations (DEAT 2006).
The South African Country Study on Climate Change identified the biodiversity sector as one of the sectors that would be most heavily affected by climate change. The area suitable for inhabitation by the country’s existing terrestrial biomes is expected to be reduced by 40% by 2050, and 44% of plant species and 80% of animal species are expected to undergo shifts in their distribution ranges. These shifts are mainly in an easterly direction and may be impeded by human-made infrastructure or lack of available natural habitat in the newly suitable area (DEAT 2006).
South Africa currently has ten GMOs approved for commercial release, comprised of various cultivars of cotton, maize and soybean exhibiting either insect resistance, herbicide resistance or both. Figure 5 shows how the number of GMOs approved for general release has increased since the first GMO was approved in 1998 (SANBI 2007b).
INSERT FIGURE 5

Figure 5 : Cumulative total number of GMOs that have been approved for general release in South Africa
The area planted under GMO crops has increased rapidly in South Africa from 8 000 hectares in 1998 to over 1.4 million hectors in 2006, and more than doubled between 2005 and 2006. This is a major change in the agricultural crops and practises in the country and so needs to be carefully monitored to assess its impact on the environment as a whole and biodiversity in particular. Figure 6 illustrates the area planted under GMO crops over this period (SANBI 2007b).
INSERT FIGURE 6

Figure 6: Area in hectares planted under GMO crops in South Africa

1.4 Freshwater biodiversity




1.4.1 Status of freshwater biodiversity

A wide variety of organisms inhabit South Africa's freshwater ecosystems, including invertebrates, molluscs, fish and others. Only fish have been assessed in terms of their conservation status. Thirty-six percent of the country's freshwater fish are threatened. Although no freshwater fish have gone extinct in the country, many have been eliminated from particular river systems (DEAT 2006).


As discussed earlier, South Africa is a water scarce country and so there are extensive pressures on its inland aquatic ecosystems. The NSBA 2004 found that 82% of main river ecosystems are in threat categories, with 44% critically endangered, 27% endangered, and 11% vulnerable. Error: Reference source not found shows the distribution of threatened main river ecosystems in the country (Nel et al. 2004).
INSERT FIGURE 7

Figure 7: Map of ecosystem status of main river ecosystems in South Africa, as assessed in the National Spatial Biodiversity Assessment 2004
Wetlands are areas that are transitional between terrestrial and aquatic ecosystems and are generally characterised by vegetation that can survive in saturated soil conditions. Wetlands perform many essential functions such as water purification and flood attenuation. An estimated 50% of South Africa's wetlands have been destroyed, but a comprehensive assessment of their conservation status has yet to be done (DEAT 2006).
Protected areas in South Africa have generally not been designed to conserve freshwater biodiversity. Approximately one third of the boundaries of protected areas are defined by rivers, which means that those rivers are essentially not protected themselves. A mere 7% of main river ecosystems are protected by statutory protected areas. Rivers are particularly difficult to conserve because they are affected by events occurring upstream from the conserved location and it is difficult to conserve the entire length of a river (DEAT 2006).
Ten percent of South Africa’s wetlands are fully protected, and a further 8% are partially protected. There is no information on the protection status of 66% of South Africa's wetlands. The remaining 16% are known not to be protected (DEAT 2006).

1.4.2 Threats to freshwater biodiversity

As discussed earlier, South Africa’s freshwater ecosystems are threatened by flow modification and pollution. In addition, poor land management leads to soil erosion which in turn leads to the siltation of rivers, making the water more turbid and impeding visibility and the penetration of light into aquatic ecosystems. An assessment of the condition of main river ecosystems done by Nel et al. 2004 classified river ecosystems according to their degree of modification. The results of the assessment are displayed in Table 3. The assessment showed that only 26% of the countries rivers are unmodified or largely unmodified. An assessment of smaller tributaries is required, however, before an accurate picture can be presented.


Table 3 Percentage of river length of main river ecosystems in each ecological state class.

Ecosystem State Class

Percentage of river length

A: Unmodified / natural

3%

B: Largely natural

23%

C: Moderately modified

48%

D: Largely modified

23%

E & F: Critically modified

3%



1.5 Estuarine biodiversity




1.5.1 Status of estuarine biodiversity

The IUCN Red Data List classifies four species of estuarine fish as critically endangered, namely doublesash butterflyfish (Chaetdon marleyi), Knysna seahorse (Hippocampus capensis), St Lucia mullet (Liza luciae), and estuarine pipefish (Sygnathus watermeyeri).

Generally, South Africa's 259 estuaries are in a poor and declining state of health, especially in heavily developed areas along the south-western Cape coast, around Port Elizabeth and in KwaZulu-Natal. The estuaries on the west coast are also under extreme pressure due to the small number of estuaries and high level of utilisation.
As part of the South African National Spatial Biodiversity Assessment, Turpie (2004) assessed the conservation status of the various estuarine groups found in South Africa. If an estuarine group is critically endangered, it means that there are very few in tact examples of that group remaining, with progressively more in tact estuaries remaining for endangered, vulnerable and least threatened respectively. Table 4 gives the number of estuarine groups per ecosystem status class (Turpie 2004).
Table 4 Ecosystem status of estuarine groups as in the National Spatial Biodiversity Assessment 2004

Ecosystem Status

Number of estuary groups

Critically Endangered

3

Endangered

5

Vulnerable

2

Least Threatened

3

There are 41 estuaries within protected areas, of which only 14 (5.4%) have a high level of protection; most of these are small in size (DEAT 2006).


1.5.2 Threats to estuarine biodiversity

The South African National Spatial Biodiversity Assessment (Turpie 2004) classified estuaries into four categories according to their health status. An estuary was classified as “Excellent” if it was in near pristine condition with negligible human impact, as “Good” if there were no major negative anthropogenic influences on the estuary or catchment, as “Fair” if there is a noticeable degree f human impact in the estuary or catchment and as “poor” if there is major ecological degradation arising from a combination of anthropogenic influences. Table 5 shows the percentage of estuaries that fell into each one of these categories (DEAT 2006, Turpie 2004).


Table 5 Percentage of estuaries in each ecosystem health class as determined by the South African National Spatial Biodiversity Assessment 2004

Ecosystem health class

Percentage of estuaries

Excellent

28%

Good

31%

Fair

25%

Poor

15%

These assessments of ecosystem health are based mainly on a study by Whitfield that uses largely subjective methods to classify estuaries. The Department of Water Affairs and Forestry has developed detailed methods for the systematic assessment of estuarine health. However, these methods are time-consuming and costly to apply and as yet have only been applied to 18 of South Africa’s 259 estuaries. These methods classify estuaries in classes from A to F the same way that rivers are classified as shown in Table 3. Where such a systematic assessment was available, the assessment performed by Whitfield was updated accordingly to produce the values in Table 5 (Turpie 2004)


Estuaries experience two broad categories of threats: direct threats that occur at the location of the estuary, and indirect threats that occur at a remote location but affect the estuary (Turpie 2004). The threats are outlined below.
Direct threats to estuarine biodiversity include:

  • Habitat alteration, for any anthropogenic activity

  • Changes in the estuarine mouth dynamics, such as manipulation of the flow to maintain certain flow levels

  • Overexploitation of estuarine resources

  • Sedimentation in the estuary due to poor catchment and mouth management

  • Disturbance of estuarine birds by humans engaging in recreational activities on and around the estuary

  • Pollution from industries, agriculture or urban areas which can alter the nutrient balance in the estuary

Indirect threats to estuarine biodiversity include:



  • Upstream abstraction of water for agriculture and other activities, resulting in a reduction in freshwater flowing into the estuary

  • Pollutants released into the water in the catchment, resulting in a reduction in water quality in the estuary

  • An increase in the freshwater inputs due to sewage discharge



1.6 Marine biodiversity




1.6.1 Status of marine biodiversity

The status of marine species has not been comprehensively assessed in South Africa and so information on the conservation status is only available for selected species, One of the groups that has been comprehensively assessed is turtles and all of the five species of marine turtle occurring in South African waters are listed as endangered or vulnerable on the IUCN Red Data List (DEAT 2006).


Many of our marine species are heavily impacted by extractive use for human consumption. Current stock assessments are not available for many important commercial marine species, so the full extent of the problem may not be appreciated. However, the stock status of eleven of our line fish species is considered collapsed. “Collapsed” means that less than 20% of the breeding stock remains, and the species is in danger of commercial extinction. These line fish species include ones that are still commonly served in restaurants all over the country, such as kob, certain rockcods and slinger (DEAT 2007).
The NSBA 2004 found that of South Africa’s 34 marine biozones, 65% are threatened, with 12% critically endangered, 15% endangered and 38% vulnerable. Most of the critically endangered marine ecosystems occur on the west coast of the country. Error: Reference source not found shows the distribution of threatened marine biozones (Lombard et al. 2004).
INSERT FIGURE 8

Figure 8: Map of ecosystem status of marine biozones in South Africa, as assessed in the National Spatial Biodiversity Assessment 2004
The coastline of South Africa extends for approximately 3000 km of which 23% is protected by inshore Marine Protected Areas (MPAs). However, only 9% of the area of these MPAs is fully protected (that is, classified as no-take zones). Of South Africa's Exclusive Economic Zone (EEZ) 1% lies within MPAs and, of this tiny proportion, less than 0.2% is no-take (DEAT 2006).

1.6.2 Threats to marine biodiversity

Extractive use of marine living resources is the major threat to marine biodiversity; with numerous species of marine fish being heavily exploited (Lombard et al. 2004).


One of the threats resulting from exploitation of marine species is the issue of bycatch and incidental mortality. This occurs when non-target species are killed by accident during the catching of target species. It is estimated that between 5% and 70% of the total catch represents bycatch depending on the targeted species and method of fishing. A serious bycatch issue is the mass mortality of sea birds in long-line fishing operations (DEAT 2006).
Marine resources are not extracted only for use as a source of food. Many fish are collected to be sold or used as aquarium fish and many shells are gathered by collectors (Lombard et al. 2004).
Development along the coastline is also a serious threat to marine and coastal biodiversity. Thirty percent of the population of the country lives in the coastal belt, defined as the area 50km inland from the high water mark (Lombard et al. 2004).
Climate change also has an effect on marine biodiversity and sea levels have risen by 1.2 mm per year over the last three decades. Increased ultraviolet radiation due to depletion of the ozone layer also causes the bleaching of coral reefs (DEAT 2006).
An emerging threat to marine biodiversity is open system mariculture, the mass production of marine fish for human consumption. Fish are kept in enclosures in the sea. This can result in eutrophication, pollution, introduction of alien species and a loss of genetic diversity in indigenous fish. Mariculture can also be conducted in closed systems, outside of the sea. This type of mariculture is preferable from a biodiversity point of view (Lombard et al. 2004, SANBI 2007b).
Diamond mining is also a threat to biodiversity, especially on the west coast of the country where extensive mining activities occur. Mining has a wide range of impacts on the marine environment including disturbance of the sea floor and pollution (SANBI 2007b).
Quantitative information on the severity and impacts of the threats to marine biodiversity are not available at this stage. However, South Africa is working on gathering such information.

1.7 Implications of biodiversity loss

The loss and degradation of South Africa’s biodiversity has serious implications for its society and economy. Natural ecosystems provide many essential services such as the provision of clean water and air, prevention of soil erosion, pollination of crops, provision of medicinal plants, nutrient cycling, provision of food and shelter and the meeting of spiritual, cultural, aesthetic and recreational needs. Large portions of the country’s economy are heavily dependent on biodiversity including the fishing industry, game and livestock ranching industry, horticulture and agriculture based on indigenous species, commercial and subsistence use of medicinal plants, ecotourism, and aspects of the film industry (DEAT 2006).


The exact economic value of these ecosystem services is complex and controversial to calculate. A range of about 100 studies have quantified the global value of ecosystem services somewhere between US$20 trillion and US$60 trillion with an average of about US$40 trillion (updated to mean 2000 US$ value).This value is similar to global Gross National Product (GNP). Unconverted, intact and conserved ecosystems are between 14% and 70% economically more valuable than ecosystems that have been converted for agriculture, forestry plantations or urban development (DEAT 2006).
De Wit (2006) conservatively valued the final consumption of ecosystems as well as the value added by ecosystems in the production of biological resources at R27 billion per annum for the whole of South Africa. This is equivalent to an average value of R 20 000 per terrestrial km2. The different biomes have different values, ranging from about R 30 000 per km2 for grasslands and savannas to about R 5 500 per km2 for Karoo. This does not include a consistent valuation of non-use values of biodiversity and thus is only a partial economic valuation of the country's biodiversity. The total value would thus be larger than this figure.
Disaggregating this partial valuation into its components shows that indirect use values such as pollination and grazing services account for two thirds of the value. Consumptive use such as crops, timber, plant, animal and aquatic resources account for 28% of the value and non-consumptive use (nature-based tourism) accounts for 6% of the total (De Wit (2006).
South Africa has a booming tourism industry, which makes the second-largest contribution to GDP of all sectors of the economy. Much of the tourism to South Africa is to experience its unique natural beauty and wildlife and thus this industry is heavily dependent on biodiversity and a loss of biodiversity could detrimentally affect the industry (DEAT 2006).
It is estimated that over 70% of South Africans use traditional medicinal plants as their primary source of health care. This is a service that is provided free of charge by intact ecosystems, often to people who would not otherwise be able to afford health care. However, the growing medicinal plant industry has resulted in many species becoming overexploited and hence increasingly scarce in the wild. This could have serious implications for the people who use these plants (DEAT 2006).
Infestations by invasive alien plants are estimated to utilise 7% of the country’s valuable water resources as well as restricting and decreasing the country’s agricultural capacity, increasing the intensity of flooding and fires, causing soil erosion destroying rivers, adding to siltation of dams and estuaries and contributing to poor water quality. Invasive alien species can also be directly responsible for the extinction of indigenous species of plants and animals. In the fynbos biome, invasive alien species are estimated to cause economic losses of about R700 million per year, which translates into a 10% annual loss of economic opportunity (DEAT 2006).
Poor management of wetlands and rivers and the catchments in which they lie can lead to detrimental effects on water availability and water quality. South Africa is a water-scarce country and much of its economic growth is limited by the availability of water. Furthermore, it has a goal to provide clean water to all its citizens. The country’s economic growth and the provision of clean water to citizens are thus dependent on correct management of its catchments and wetland and river ecosystems (DEAT 2006).
Estuaries, with their unique interactions between salt and freshwater perform a range of important ecosystem services including the provision of breeding grounds for economically important species of marine fish, and channelling nutrients and sediments from rivers into the sea, contributing to the productivity of marine ecosystems. The value of estuarine fisheries and their contributions to marine fisheries is estimated at R923 million per year. The correct management of estuarine ecosystems is thus essential to these portions of the economy (Turpie et al. 2004).
Many people in coastal rural areas depend directly on marine biodiversity for their livelihoods. Such subsistence activities, as well as large commercial fisheries, are dependent on the correct and sustainable management of marine biodiversity. Overexploitation of marine living resources results in lowered availability of these resources to the people who depend on them (Lombard et al. 2004).
The overall socio-economic well-being of the population of South Africa is thus directly dependent on the conservation and sustainable use of its biodiversity. Continued extensive loss of biodiversity and ecosystem health could have dire social and economic consequences. It is thus essential that sustainable biodiversity management is prioritised in the country.

References

DEAT. 2006. South African Environment Outlook. South African National Department of Environment Affairs & Tourism, Pretoria.

DEAT. 2007. South Africa's National Biodiversity Framework. Draft. Published in Government Gazette 30027 of 29 June 2007.

De Wit, M.P. 2006. The value of biodiversity to the South African economy: a preliminary study Internal draft report prepared for South African National Biodiversity Institute as part of the project “Development of the SANBI Business Case” by the Cooperative of Independent Consultants (CIC)

Driver, A., Maze, K., Rouget, M., Lombard, A.T., Nel, J., Turpie, J.K., Cowling, R.M., Desmet, P., Goodman, P., Harris, J., Jonas, Z., Reyers, B., Sink, K. & Strauss, T. 2005. National Spatial Biodiversity Assessment 2004: Priorities for Biodiversity Conservation in South Africa. Strelitzia 17. South African National Biodiversity Institute, Pretoria.

Lombard, A.T., Strauss, T., Harris, J., Sink, K., Attwood, C. & Hutchings, L. 2004. National Spatial Biodiversity Assessment 2004: Technical Report. Volume 4: Marine Component. South African National Biodiversity Institute, Pretoria.

Mucina L. & Rutherford M.C. (eds) 2006. The vegetation of South Africa, Lesotho and Swaziland. Strelitzia 19. South African National Biodiversity Institute, Pretoria

Nel, J., Maree, G., Roux, D., Moolman, J., Kleynhans, N., Silberbauer, M. & Driver, A. 2004. National Spatial Biodiversity Assessment 2004: Technical Report. Volume 2: River Component. CSIR Report Number ENVS-S-I-2004-063. Council for Scientific and Industrial Research, Stellenbosch.

Rouget, M., Reyers, B., Jonas, Z., Desmet, P., Driver, A., Maze, K., Egoh, B. & Cowling, R.M. 2004. National Spatial Biodiversity Assessment 2004: Technical Report. Volume 1: Terrestrial Component. South African National Biodiversity Institute, Pretoria.

SANBI. 2007a. South African National Biodiversity Institute Threatened Plants Database.

SANBI. 2007b. National Biodiversity Monitoring & Reporting Framework.

Turpie, J.K. 2004. National Spatial Biodiversity Assessment 2004: Technical Report. Volume 3: Estuary Component. South African National Biodiversity Institute, Pretoria.





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