a review of freshwater ecosystems in the northern cape

7/25/2019 A Review of Freshwater Ecosystems in the Northern Cape

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in the

Northern Cape

Province

Review

of the

Freshwater

Ecosystems

DEPARTMENTOF ENVIRONMENT

AND NATURE

CONSERVATION



DEPARTMENT OF ENVIRONMENT

AND NATURE CONSERVATION

REPORT 58

COMPILED BY PP RAMOLLO

2010

in the

Nort

Province

Review

of the

Freshwater

Eco

hern Cape

systems



Acknowledgements

I am grateful to my supervisor Ms Elsabe Swart for her assistance and creative inputs she

provided during the drafting of this document, Mr Julius Koen for editing this document, Ms

Lerato Sebuseng for the information provided, Mrs D Samson, Mr A Mabunda, Head of

Department, Mrs Mokhali, DTEC staff and management for financial support and making

these possible. I also like to extend my sincere thanks to Mr Bheki Kunene for maps

(Department of Rural Development in Kimberley), Ramogale Charles Sekwele (Department

of Water and Environmental Affairs in Pretoria), Dolamo Kabelo Stephinah (University of

Limpopo), Tumelo Dilotshohle and Iris Jonathan (John Taolo Municipality). The following people

from Department of Water Affairs in Kimberley are acknowledged for their contributions: Sam

Dywili, Boitumelo Moalusi, Noe Malise, Abe Abrahams, Debbie Sharp and Gawie Van Dyk.

Lastly, my sincere thanks to Dr WJ Luus-Powell (University of Limpopo), Prof A Jooste (University

of Limpopo) and Prof M Seaman (University of Free State) for editing this document,

information provided and unconditional support.



TABLE OF CONTENTS

1 Introduction

2 Background

2.1 Climate

2.2 Geology and soils

3 Threats to freshwater in the Province

3.1 Industries and Mining

3.2 Agriculture and sewage pollution

3.3 Canalisation and abstraction

3.4 Invasive species in the Northern Cape Province

3.5 Climate change

4 Wetlands of the Northern Cape Province

4.1 Definition of Wetlands

4.2 Ecological role of Wetlands

4.3 Standing Waters

4.3.1 Perennial and non-perennial Pans

4.3.2 Springs/Eyes

4.3.2.1 Dolomite Springs

4.3.2.2 Warm-Water Springs

4.4 Rivers

4.4.1 Perennial Rivers in the Province

4.4.1.1 Orange River

4.4.1.2 Vaal River

4.4.2 Ephemerial Rivers

5 Fish checklist of the Northern Cape Province

6 Conservation status

7 Summary

8 Recommendations

9 Glossary

10 References

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1. Introduction

Freshwater ecosystems are aquatic systems which include lakes and ponds, rivers and

streams, reservoirs, wetlands and groundwater. Freshwater ecosystems are inhabited by

numerous organisms such as fish, amphibians, aquatic plants, water birds and invertebrates.

Rivers form an important part of our ecosystem by having the force to shape our landscape.

They are dynamic systems which have evolved over a very long time in response to South

Africa’s extremely variable climate. They continue to be shaped by events occurring at

different scales in time and space. There are two major factors influencing rivers and

streams namely, flow and catchment: • Flow – the flow pattern affect the physical form and

the ecology of a waterway and is very much driven by climate. Flow variability is a key

determinant of river shape and functioning of the biota which live in rivers. • Catchment – the

slope, geology, soil, vegetation and land use practices have some effect on the rivercondition, either through influencing streamflows, water quality, channel features, energy

supply or riparian and floodplain vegetation.

The indicators of wetland and river health can be divided into three main categories:

biological, chemical and physical indicators. Biological indicators are numerous and are

probably the most commonly measured parameters for determining the overall ecosystem

health. Possible indicators include algae, vegetation, microbial assemblages, macro-

invertebrates, fish, amphibians and bird communities. Chemical indicators of wetland and

river health include water and soil chemistry, parameters such as nutrient concentrations,

dissolved oxygen and pH. Physical indicators include measurement of water depth,

hydrology and seasonality (Wray et al. 2006). The River Health Programme in South Africa

uses biological indicators to provide quantitative and qualitative information to evaluate river

health. In making decisions on protecting and maintaining the health of rivers and their

ecological integrity, communities and government collectively need to balance the economic,

social and environmental values associated with rivers as outlined in the National

Environmental Management Act 107 of 1998. However, it is helpful to have identified what ahealthy river is to assist communities with these decisions. A healthy river is defined as a

river which retains the major ecological features and functioning of that river, and be able to

sustain these characteristics into the future.

The Northern Cape Province is predominantly semi-arid and the largest province in South

Africa. Due to low rainfall and high evaporation in the province, the freshwater, which is a

global scarce resource, is highly limited. Freshwater is not readily available in the Northern

Cape Province and there is a demand for this scarce resource due to the rapid increase of

population growth, urbanization, industrialization and agriculture. Rapid population growth in



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the province together with an increase in upstream users, leads to a greater demand on and

increased pollution of the water resources in the province. Water quality in the province is

strongly influenced by the usage and management practices in the upper and middle

catchments. Although two of the largest rivers (Orange-Vaal River System) in the country

are running through the Northern Cape Province, there is a great demand for water fromupstream users. In fact, the reality is that there is no surplus water currently available in

these two rivers. Although mining, industries and agriculture play a pivotal role in the

economy of the province, they also place a demand on the availability of water and cause

the reduction in aquatic and terrestrial biodiversity.

In the Northern Cape Province the freshwater ecosystem is compromised due to poor

management and political influences. Freshwater ecosystem provides social, economic and

political benefits and makes human life both possible and worth living e.g. wetlands and

trees trap carbon dioxide that contributes to climate change. Wetlands also play a pivotal

role by filtering pollutants and reducing water floods. Rivers support life to fish which is a source

of protein to poor communities. Failure to address these problems will have long-term social

and economic costs, as well as potentially irreversible effects on biodiversity and the

availability of healthy water. This report provides a review of some of the freshwater

ecosystems in the province.

The report will concentrate on river systems to a lesser extent, wetlands and standing water,

while only mentioning that groundwater also forms part of our freshwater systems without

elaborating on it. Similarly, associated invertebrates and aquatic plants will not be discussed

in detail. The aim of this report is to give the reader a general overview of freshwater

systems in the province, highlighting some aspects that members of the public can easily

observe and relate to, rather to present a comprehensive scientific inventorying of all

elements of our provincial freshwater systems.

2. Background

2.1 Climate

The Northern Cape Province is predominantly a semi arid area with low rainfall. Climate

plays a vital role in determining the availability of water resources, the nature of the natural

landscape and vegetation types. There is variation in seasonal and daily temperatures

throughout the province. During winter, the southern areas of the province, such as

Sutherland, are extremely cold, occasionally with temperatures below -10ºC. In areas like

Upington, summers are harsh, dry and hot with temperatures usually between 30°C and



8

40°C, sometimes exceeding 40°C. Eastern parts of the province receive summer rainfall

events associated with isolated thunderstorms. However the western parts, namely the

Succulent Karoo areas receive winter rainfall. According to Palmer & Hoffman (1997) and

Bradstock (2005) the annual rainfall varies considerably throughout the province with rainfall

ranging from 50mm in the west to 400mm in the east (Figure 1). Evaporation rate is veryhigh during the hot seasons, which significantly reduce the water volume in the rivers.

Potential evaporation can be as high as 3 000 mm per year, which is several times more

than the annual rainfall (DWAF 2004a).

Figure 1: Mean annual precipitation (South African Weather Service)

2.2 Geology and Soil

The rivers in the province meander through various geological structures which give rise to a

variety of soil types, with deep alluvial soils occurring along the Orange River. The province

is dominated by the Karoo Basin and consists mostly of sedimentary rocks and some

dolerite intrusions. The south and south-eastern part of the province is underlined by shale

and mudstone. The south-west of the province consists of quartzite, siltstone, sandstone and

granite whilst the west coast is dominated by the Namaqualand formations. This area is hilly

to mountainous and consists of granites and other metamorphic rocks. The central areas are



9

generally flat with interspersed salt pans. Kimberlite intrusions punctuate the Karoo rocks,

giving the province its most precious natural resource, namely diamonds. The eastern part of

the province comprises of sandstone and subordinate dark shale, quartzite and andesitic

lava, whilst the western part comprises mainly of granite, quartzite, limestone, shale with

subordinate mudstone and sandstone, quartzite, andesitic lava and dolomite (Figure 2). Thenorthern part of the province is dominated by sandstones and tillite whilst the Kuruman

region is dominated by dolomite.

Figure 2: Geology of the Northern Cape. (Map by Bheki Kunene, Department of Land Affairs Affairs in Kimberley, 2009 based on information from AFRICON).

3. Threats to freshwater in the province

3.1 Industries and Mining

Human activities such as industrialisation, domestic and agricultural practices expose the

rivers of Northern Cape to various pollutants. The upper reaches of the Vaal River is

characterised by a large number of mining activities such as coal and semi- precious

minerals to precious minerals. In the Lower Vaal Water Management Area, the alluvial

diamond minings are rife and some operate illegally. The diggings have resulted in severe



degradation of the riparian vegetation. They have removed large quantities of topsoil and

physically destroyed the floodplain. Currently the riparian zone of the following areas are

severely degraded and looks like a desert: Schmidtsdrift (Figure A&B), Barkly West (Figure C),

Delportshoop (Figure D), Winsorton (Figure E), Gong-Gong (Figure F), Douglas and Vaalbos

Nature Reserve. After prospecting the diamond diggers don’t rehabilitate the area. The areas inDelportshoop, Gong-Gong, Windsorton and Vaalbos are not at all rehabilitated and thus pose

a threat to the safety of livestock and humans. Some sections of the river are diverted to allow

diamond in Windsorton area. During rainy seasons the silts are washed into the waterway and

cover the spawning sites of the fish (Figure 3A to F). The release of pollutants into the rivers

alter the pH of the water which increases the toxicity of the metals that severely affect fish,

frogs and macro-invertebrates. Recent studies on water quality of the Vaal River showed

high levels of pollutants especially metals and total dissolved salts mostly attributed to mining,

agricultural activities and geochemical formations.

A B

C

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D



Figure 3 A-F:

F

3.2 Agriculture and sewage pollution

The Jukskei/Crocodile river systems which are tributaries of the middle Vaal River contribute

to eutrophication because of the raw sewage and treated waste effluent it receives from the

Gauteng area. The return flows from agricultural activities along the banks of the Lower

Orange-Vaal River contribute to high levels of nutrients which cause algal blooms and alien

plant growth and result in depletion of oxygen. Consequently these may potentially impact

negatively on the aquatic flora and fauna. The Lower Orange-Vaal River 1 has relatively high

salinity concentrations due to irrigation return flows (agricultural activities) (Figure 4 A) and

the geological formations.

More raw sewage (nutrients) are added to the Lower Vaal River in the Warrenton area due

to poor Municipal infrastructure and maintenance of sewage treatment works, poor planning,

budgeting and management which has been continuing for years (Figure 4B&C). These

contaminants cumulate and impact in the Lower Orange River. If this kind of sewage

pollution continues the river water quality will be detrimental to indigenous fish and the water

will be unsuitable for human and animal consumption. Untreated sewage can pose a major

ecological disaster and a serious health hazard to fish, birds and humans. Sewage

contamination in the freshwater ecosystems is dangerous and can cause illnesses like

cholera, typhoid and bilharzia (Craun et al. 1998). People and livestock can be affected if

they drink this kind of water or by eating vegetables that were watered with sewage water.

Faecal pollution affects all kinds of flora and fauna which can result in the loss of

biodiversity.B

Mining activities in the Lower Vaal River; A. & B. Alluvial mining in Schmidtsdrift; C. Illegal

mining in Barkly West; D. Delportshoop; E. DWA official checking for water use licence

in Windsorton; F. Illegal mining in Gong-Gong.

There are lots of algae in the Lower Vaal River from Warrenton to its confluence with the

Orange River in Douglas (Figure 4D) which is as a result of cumulative impacts from the

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E



upstream, agricultural practices and sewage water in the Warrenton area (Figures 4B&C). In

order to address this problem the provincial and national government should intervene with

the municipalities who fail to comply with the National Water Act 36 of 1998. However, co-

operative governance is also needed between government organisations and non-

government organisations to address these kinds of problems.

1 According to Department of Water Affairs’ Catchment Management Areas the Lower Vaal River stretches

from Bloemhof Dam to Douglas, while the Lower Orange is from Orange-Vaal confluence to Orange RiverMouth. Lower Orange-Vaal River refers to the collective of the two aforementioned river stretches.

Figure 4 A-D: A. Irrigation return flows in the Orange River; B. & C. Sewage flowing in the Vaal River

in Warrenton; D. Algal blooms in Barkley West in the Lower Vaal River.

A B

C D

3.3 Canalisation and abstraction

These drainage techniques are prevalent throughout the Orange-Vaal River system and

result in water flow modification. Stream canalisation and water abstraction, both legal and

illegal, compromise the water quality; reduce river volume, flow and leads to the loss of

riparian vegetation (Figure 5A&B). Riparian vegetation plays a role in increasing biodiversity

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and also provides habitat for fish and macro-invertebrates. It functions as a buffer to aquatic

systems thereby reducing the negative effects from pollutants. It controls stream-bank

erosion and subsequent sedimentation, degradation of water clarity and quality, and

contributes to controlling pathogens and eutrophication (Walker 1993). Riparian vegetation

also traps carbon dioxide from the atmosphere.

Figure 5 A-B: A. Water abstraction in Lower Orange River; B. Illegal water abstraction in the Lowerin the Lower Vaal River.

3.4 Invasive species in the Northern Cape Province

The Orange-Vaal River system is colonized to various extents by faunal and floral alien

species. The Common carp (Cyprinus carpio) and mosquitofish (Gambusia affinis) are two

examples of alien fish found in Lower Orange-Vaal River system, while the red water fern

(Azolla filiculoides) (Figure 6A), spiked water milfoil (Myriophyllum spicatum) ( Figure B ) and

water hyacinth (Eichhornia crassipes) (Figure 6C) are examples of invasive aquatic plant

species. These alien plants are widely distributed in the Lower Vaal River. They are also

found submerged in a waterbody covering the waterway and furthermore preventing sunlight

to penetrate, which results in oxygen reduction which can lead to massive fish kills. The

AB

it can spread further downstream. The spiked wa

whole of the Lower Vaal River and is further spreading in the Lower Orange River.

presence of water hyacinth in Warrenton, Warrenvale and Windsorton is a major concern as

ter milfoil has aggressively colonized the

Severe infestation of other invasive alien plants include for e.g. sweet prickly pear (Opuntia

ficus-indica), caster oil plant (Ricinus communis), eucalyptus (Eucalyptus spp.), wild tobacco

(Nicotiana glauca), Sponge-fruit saltbush ( Atriplex lindleyi), old-man saltbush ( Atriplex

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Figure 6 A-C: A. Red water fern (Azolla filiculoides) in the Vaal River Windsorton B. Spiked water

milfoil (Myriophyllum spicatum) in the Lower Vaal River, Barkly-West; C. Waterhyacinth (Eichhornia crassipes) in the Lower Vaal River in Warrenvale.

B C

nummularia), pink tamarisk (Tamarix ramosissima), giant reed (Arundo donax) and honey

mesquite (Prosopis glandulosa var. torreyana/velutina) are aggressive invaders of riparian

zones and are widely distributed along the rivers in the province. The alien plants are

opportunists which use more water resources than our indigenous plants. According to

DEAT (2004) mesquite may consume 200 million m3

water per year reducing the amount ofgroundwater available to farmers and rural communities.

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A



3.5 Climate change

Climate change is the natural cycle (if not accelerated by human activities) through which the

earth and its atmosphere accommodate change in the amount of energy received from the

sun. The climate goes through warm and cold periods, taking hundreds of years to complete

one cycle. Changes in temperature also influence the rainfall but the biosphere is able to

adapt to a changing climate if these changes occur over centuries. Unfortunately, human

intervention is currently causing the climate to change too fast. The global climate system is

driven by energy from the sun. Several gases in the atmosphere act to trap the energy from

the sun, thus warming the earth (Water Wheel 2008). These gases are called greenhouse

gases and the process is the greenhouse effect. Without this there would be no life on earth.

Human activities over the last 200 years, particularly the burning of fossil fuels (oil, coal,

natural gas) and the clearing of forests, have increased the concentration of greenhousegases in the atmosphere. This is likely to lead to more solar radiation being trapped, which in

turn will lead to the earth’s surface warming up – the enhanced greenhouse effect.

The impact of climate change on biodiversity is difficult to assess since it depends largely on

the rate of change and the compounding effects of other pressures such as habitat loss and

fragmentation (Poff et al. 2002). While most scientists agree that the climate is changing, it is

not yet possible to distinguish human-induced change from natural climatic variations (Njau

2007). According to Poff et al. (2002) the increases in water temperatures as a result of

climate change will alter rainfall patterns, fundamental ecological processes and the

geographic distribution of aquatic species. Such impacts may be ameliorated if species

attempt to adapt by migrating to suitable habitat. However, human alteration of potential

migratory corridors may limit the ability of species to relocate, increasing the likelihood of

species extinction and loss of biodiversity. As the global climate warms, the preferred

climatic conditions for a species will shift to higher altitudes and latitudes (Poff et al. 2002).

The survival will depend on its ability to relocate quickly enough and the availability of

alternative habitats. Species most at risk are those with small population sizes and ranges

that have slow growth rates with poor dispersal and recruitment abilities. Therefore alien

species can possibly out-compete indigenous species for food and habitat (Dukes and

Mooney 1999). With the current status of the Orange-Vaal River system, alien species are

predicted to dominate the system.

According to Houghton et al. (2001) the average global surface temperatures are projected

to increase by 1.5 to 5.8ºC by 2100, this projected change in climate will place additional

pressure on already-stressed freshwater ecosystems. Climate change contributes to

evaporation of water in the rivers which causes the high concentrations of the total dissolved

15



salts. In the Northern Cape Province, freshwater is salty during the hot seasons but

minimally improves after rain. Furthermore rising temperatures can extend the habitats of

mosquitoes that carry the malaria parasite in the warm areas, because mosquitoes tend to

breed faster as temperatures get higher, thus shifting the boundaries of latitude and altitude

for malaria transmission (Dhiman et al. 2008). Planting trees can help to curb the problem ofclimate change as they trap carbon dioxide for photosynthesis.

4. Wetlands in the Northern Cape

4.1 Definition of Wetlands

A wetland as defined by the National Water Act (Act No. 36 of 1998), refers to land which is

transitional between terrestrial and aquatic systems where the water table is usually at or

near the surface, or the land is periodically covered with shallow water, and which under

normal circumstances supports or would support vegetation typically adapted to life in water

saturated soil. Although, most pans show distinct zonation of vegetation at any one time,

these zones and the plant species that occupy them, vary in response to fluctuating water

levels.

The zones often relate to the topography of the pan which in turn defines the extent of open

water, the depth of the water, and the steepness of transition and boundary gradients. Theseall influence what plant species may be more commonly associated with for example, the

floor, as opposed to the margins and areas upslope. Even within zones there may be a

patch of plant communities or stands of vegetation that also varies with time. The dynamic

nature of most of the pans also allows the colonisation of areas by opportunistic plant

species such as annual grasses and certain sedges which results in a considerable degree

of variability in plant species composition and richness between pans. Types of wetlands

include sponges, bogs, vleis, swamps, marshes, dams, springs and pans amongst others.

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4.2 Ecological role of Wetlands

In the past, wetlands were considered wasteland, and many were drained or filled in so that

they could be farmed or built upon. Recently the values of wetlands have been recognized

and efforts have been made by the Department of Water and Environmental Affairs (DWEA)

and the South African National Biodiversity Institute (SANBI) to protect these ecosystems.

Despite the current legislation which encompasses the protection of wetlands they are still

disappearing in the Northern Cape under the pressure from agricultural activities.



17

and sediment from runoff water before they reach an open body of water. They also facilitate

education and research, serving as valuable recreational areas for activities such as hunting,

fishing and bird watching (Palmer et al . 2002).

4.3 Standing Waters

4.3.1 Perennial and non-perennial pans

Northern Cape Province has the highest abundance of pans in South Africa, mostly

dominated by non-perennial pans that only have water after rain (Figure 7). The pans in the

vicinity of Victoria West and De Aar are extremely important for the threatened and endemic

Blue Crane. In the Kalahari region around Rietfontein there are good endorheic pans which

are of archeological importance. There are several salt pans to the west and northwest of

Brandvlei inter alia Rietfontein Pan, Commissioner's Salt Pan, Dwagga Salt Pan, Bitterputs

se Pan, Konnes se Pan. The central Karoo in the Brandvlei area is generally flat with

abundant interspersed salt pans (Figure 7) associated with the fossil rivers. When filled with

water, these pans are important to waterbirds.

area include Brandvlei, Flaminkv

fauna in Grootvloer Pan. Heuningvlei is a

Verneukpan is the largest perennial pan in the Nama Karoo and in all of South Africa with a

length of 33.5 km long and 11 km width (Lloyd and Le Roux 1985). Other major pans in this

lei, Vanwyksvlei and Grootvloer pan (Figure 7). According

to Lloyd and Le Roux (1985) the perennial Grootvloer pan plays an important role in fish

migrations, allowing the free interchange of indigenous fish between the Sak and Orange

Rivers. Hamer and Rayner (1996) recorded an exceptionally high diversity of crustacean’s

natural saltpan found in Kuruman. It supports a

wide variety of birds. The pan is under threat from overgrazing. The two pans in the

northwest of Upington namely: Groot Witpan and Witpan are mined for salts. South of the

latter mentioned pans are two smaller pans which were mined in the past, Klein Witpan and

Lankpan. A pan which was also mined in the past is Soutpan, which lies 3,5km southwest of

There are lots of functions and ecosystem services that wetlands provide, amongst others

they slow down the flow of water and trap pollutants, limiting flooding and cleaning water.

Wetlands are areas rich in biodiversity, the plants are in abundance because of the nutrients

in the soil. These plants provide shelter and food for animals. There are varieties of plants

and animals that are Red Data Listed (RDL) species that depend on wetlands, and withoutthe habitat that wetlands provide, they would not be able to survive. According to

NWWATER (2008) wetlands lessen global warming by locking up huge amounts of carbon

(C) in peat rather than allowing carbon dioxide (CO2) to be released in the atmosphere.

Wetlands improve water quality serving as excellent water filters to remove nutrients, wastes



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Askham. The flamingoes are found in, amongst other pans, the Soutpan and Groot Witpan

south of Danielskuil during high rainfall years. The Kathu Pan located near Danielskull is of

major archaeological site recognized world wide for its stones. It is drained by the Gamagara

River a tributary of the Kuruman River. The Ganspan near Jan Kempdorp consist of two

permanently inundated pans. These pans are filled with water coming from the irrigationscheme of Vaalharts. The pans support large bird populations as well as populations of the

smallmouth yellowfish (Labeobarbus aeneus) and the largemouth yellowfish (Labeobarbus

kimberleyensis). The pans are also an angling spot during the summer season.

The Platfontein Pan systems are located to the southwest of Kimberley. These pans support

populations of flamingos and other waterbirds during periods of water availability. Volstruis

Pan is located on Rooipoort west of Kimberley in the property of the De Beers Consolidated

Mines. It support habitat for mammals. Benfontein Pan also known as AlexandersfonteinPan is located in the De Beers property southeast of Kimberley support habitat for mammal

and birds. The Kamfers Dam is found in the town of Kimberley. It is an endorheic pan of

ecological importance in Kimberley. It is permanent, shallow, saline and provides suitable

habitat for the Greater and Lesser Flamingos and Waterfowls. The dam’s water quality is

poor due to the sewage effluent and other pollutants entering via the stormwater (Van

Niekerk 2000). Currently the water volume of the pan is high due to sewage effluent from

Homevale sewage works. There are no fish species appearing in the pan due to high salinity

and pH. The toxic metals are very low but need further long-term monitoring. There are high

concentrations of major cations and nutrients in the pan. The pan is fairly researched in

terms of water quality, algae and invertebrates. Currently toxic cyanobacteria which are a

health hazard do not appear in the pan. This needs serious attention as it can eliminate all

the birds in the pan if there is an outbreak.

Pans are also prevalent along the Namaqualand coastline, e.g.Visagiespan and

Rietfonteinpan south of Alexander Bay. Near Port Nolloth, Aerodrome Pan is found. The site

is important for the breeding of Damara Tern, South Africa’s rarest coastal breeding species.This bird is endemic to the west coast of South Africa and Namibia and ranks amongst the

world’s smallest terns. In the Kamiesberg Mountains of Namaqualand various ephemeral

wetlands are found. These wetlands contain high levels of plant and invertebrate endemism.

The wetlands are threatened by grazing, alien invasive khakibos (Inula graveolens) and

cultivation (Swarts et al. 2009).

The Orange River Mouth (ORM) is one of the important wetlands in South Africa. It was

declared a Ramsar Site in 1991, but removed to be placed on Montreax Record2 in 1995

due to the collapse of salt marshes. The site is a unique ecosystem within the bioregion and



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together with the surrounding pans they supply habitat to fishes, resident birds and local

migrant waterbirds. It is highly degraded by adjacent alluvial mining activities and the

changes in the water flow of the Orange-Vaal River system. The Orange-Vaal River is

experiencing increasing demand for water from upstream users, and with the proposed two

2

It is a record of Ramsar sites where changes in ecological character have occurred, are occurring or to occur.

dams in the system (one in the upperstream and one in Vioolsdrift) could essentially improve

the amount of water reaching the Orange River Mouth that will lead to further growth of salt

marshes. The wetland is currently under rehabilitation.

4.3.2 Springs/ Eyes

4.3.2.1 Dolomitic Springs

Dolomitic eyes are waterbodies fed by groundwater originating from fractures in the

underlying dolomite. The water from these dolomitic features is typically alkaline (pH 7.5-9.3)

having picked up magnesium and calcium carbonates through solution from the main

dolomite. The Northern Cape Province has a perennial and seasonal number of these

unique natural features most of which are classified as springs ranging from small trickles to

the perennial Eye of Kuruman. Some springs are seasonal; larger ones have big catchments

areas and are not affected by one year’s rainfall and some have dried up permanently and

are visible during heavy rainfall or major floods (Van Dyk 2009 Pers. Comm).

In Campbell there are few springs. In the Karoo region one spring is located in Griquatownand is protected by the Municipality. One spring is also found in De Aar. Along the Kuruman

River are more springs of different sizes and endurance. Another spring in the Ga-Mopedi

creates a pond in winter that sustains waterfowl. The eyes along the river do not usually

provide sustained flow of water for any distance; most times the riverbed is a series of ponds

and marshes, which disappear shortly downstream, varying by season. The following areas

in Kuruman region have flowing springs: Batlharos, Bothetheletsa spring at Bothetheletsa

Nature Reserve, Bothitong, Bushy Park, Dithakong, Ditshipeng, Manyeding at Manyeding

Reserve, Maruping, Mtswetsaneng, Tsineng, Kuruman first eye and second eye, GrootKoning is located in the south and southeastern part of Kuruman at Konong Reserve, and

Tsinineng spring at the lower Kuruman (Figure 7) (Sebuseng 2009 Pers.Comm). The

Kuruman Eye is the biggest natural fountain/spring in the Southern Hemisphere. It is

supplied by water that flows through a system of interconnected solution channels in the

dolomite, which is dammed up by a diabase dyke and forced to the surface. It provides over

20million litres of crystal-clear water everyday (Norman and Whitfield 2006). Though there

are likely



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4.3.2.2 Warm-Water Spring

A Warm-water spring is a spring with water temperature substantially higher than the air

temperature of the surrounding region. Most of the warm-water springs result from the

interaction of groundwater with magma or with solid but still-hot igneous rocks. Some,

however, are not related to volcanic activity. In such cases, deep circulation of water is

thought to carry the water to the lower parts of the Earth's crust, where the temperature of

the rocks is high. The Riemvasmaak thermal spring is the only known hot spring in the

Northern Cape Province and its water is associated with healing power. It is the only natural

source of warm water away from the course of the Orange River. It is estimated to yield

approximately 1800 litres per hour (von Backstrom 1962) and its temperature ranges

between 30-50 degree Celsius.

has never been a thorough survey of all springs in the province, some of the flowing springs

have historical water quality data since the 1950’s till today.

Figure 7: Wetlands distribution in the Northern Cape Province. (Map by Bheki Kunene, 2009 basedbased on information from AFRICON).



4.4 Rivers4.4.1 Perennial Rivers in the Province

4.4.1.1 Orange River

The Orange River which originates from the Maluti Mountains in Lesotho is the largest and

longest river in South Africa (SA). The river in Lesotho is known as the Senqu River. It flows

westward for 2 300 km to the Richtersveld area where it flows into the Atlantic Ocean

and it is the major water resource of the Northern Cape Province. During flood events the

Orange River flows directly into the Atlantic Ocean and sometimes has its access to the sea

blocked by sand-bars during lower rainfall events (DWAF 2004b). It is thus not a true estuary

and is called a river mouth. The tributaries of the Lower Orange River are the Brak, Seekoei,

Ongers and Hartebeest Rivers from the south in the Lower Orange River and the Fish and

Molopo Rivers from the Namibian side and (Figure 8). The Fish River is the largest

21

contributor to the Orange River downstream of the Orange / Vaal confluence. Although

occasional runoff occurs in the upper reaches of the Molopo River, no record exists of flow

having reached the the Orange River. Previous recordings of flow in the lower reaches of the

Molopo and / or Kuruman Rivers were in 1933 and again in the 1974/5 and 1975/76 seasons

(DWAF 2004a).

The Orange River is highly regulated by more than 29 dams (including weirs), with major

dams such as the Katse Dam (highest dam in Africa at 185m high) in Lesotho, the Gariep

Dam (88m high) in the Free State Province and the Vanderkloof Dam in the Northern Cape

having been built for irrigation, flood controlling and electricity generation (Earle et al. 2005).

These dams have been constructed to impound the surface-water runoff during rainfall, in

order to store it for later use or release downstream during the dry season for ecological

needs and irrigation purposes. The development of these dams resulted in flow regime

changes, facilitating blackfly breeding to such an extent that it negatively influenced stock

farming practices e.g. These blackflies feed on the blood of livestock, often causing

inflammatory and allergic reactions that result in stock losses.

The Gariep Dam is the largest dam in SA with a storage capacity of 5 600 million cubic

metres and the Vanderkloof Dam is the second largest in SA with a storage capacity of 3

200 million cubic metres which produce hydro-electricity (Water Wheel 2006). Amongst all

the SA Dams the Vanderkloof is the highest with a total height of 108 metres. The total

demand for water in the Lower Orange River system is 2230 million m³/a. The biggest user

of water in the Lower Orange River is agriculture {(970 million m³/a (43%)}, followed by

evaporation losses with {(620 million m³/a (28%)}, environmental demand {(290 million m³/a

(13%)}, {(Operational losses of 270 million m³/a (12%)} and lastly the urban demands of 80

million m³/a (4%) (Bapela 2009).



22

The Gariep and Vanderkloof hydro-electricity stations have considerably changed the flow

characteristics in the Lower Orange River. The Vanderkloof Dam is currently the last main

storage structure on the Orange River and controls the flow regime of water along the

1 400 km stretch of river between the dam and the mouth at Alexander Bay on the Atlantic

Ocean. The natural flow regime of the Orange River varies according to years, seasons andoccasional heavy floods as well as intermittent droughts. The naturally low winter flows are

further influenced by the management (release or not) of water from dams in response to

electricity generation. There is also high water evaporation and high demand of water

downstream due to irrigation purposes. These trends are experienced in spring, especially in

October and November. The reduction in water volume poses a serious threat to the integrity

of the river mouth wetland. Engineers and ecologists say that if a dam is built in the Lower

Orange River in Vioolsdrift it could improve the flow management of the lower part of the

river and ensure that sufficient amounts of water are released into the system at all times,

which would maintain the integrity of the Orange River Mouth ecosystem.

According to the survey done by Department of Water and Environmental Affairs in 2008

and 2009, the aquatic macro-invertebrates diversity indicated that the water quality of the

Lower Orange River is in a good state and there is deterioration at some sites. This can be

related to the agricultural activities and the cumulative impacts from upperstream. The

chemical analysis showed the high levels of salts throughout the system which is attributed

to extensive agricultural activities and geological formations. There are high levels of copper,

cadmium, lead, zinc and aluminium in Keimoes, Kakamas and Pella in the Orange River

which needs further investigation.

In the lower reaches of the Orange River, the toxic algae Cylindrospermopsis raciborskii was

first detected during the summer of 2000 and again in 2003 and 2005 respectively (Janse

Van Vuuren and Kriel 2008). C. raciborskii is a problem-causing cyanobacterium capable of

releasing potent toxins and has become increasingly prevalent in the lower reaches of the

Orange River. The blooms of C.

raciborskii lead to several problems including taste andodours, as well as making water treatment difficult and fish kills (Janse Van Vuuren and Kriel

2008). The Baccillariophyceae, Chlorophyceae and Cyanophyceae were found to be the

most abundant algae classes in both the Vaal and Orange Rivers (De Beer 2008).

Table 1 indicates the algae that have been recorded in different seasons in the Lower

Orange-Vaal River system by Chutter (1968), De Beer (2008), Palmer (1997) & Janse Van

Vuuren and Kriel (2008).

In terms of habitat integrity, the lower sections of the Orange River are impacted mostly by

growing infestations of mesquite (Prosopis spp), river red gum (Eucalyptus camaldulensis),



23

giant reed (Arundo donax) and wild tobacco (Nicotiana glauca). The alien invasive shrubs

caster oil plant (Ricinus communis) is also observed in the riparian vegetation. These woody

shrubs species are commonly found in riparian areas, and are responsible for significant

river yield losses, as well as land degradation.

Table 1: Planktonic algae recorded in the Lower Orange - Vaal River System.

Class Genus & species

Cyanophyceae Anabaenacircinalis(filament)

Aphanocapsaspp. (colony)

Cylindrospermopsis raciborskii

Merismopediaminima (colony)

Merismopediaspp (colony)

Microcystisaeruginosa(colony)

Mi.aeruginosa(loose cells)

Oscillatoria spp.Filament

Bacillariophyceae Asterionellaspp. Cyclotella spp.(10-20um) Centric diatoms-small (<8um) Cocconeis spp.

Cymbrella spp. Diatoma spp. Gyrosigma spp Melosira(=Aulacoseiragranulate (f)

Navicula spp.(pennate)

Nitzschia spp.gracilis (150um)

Navicula spp.(pennate)

Pennatediatoms (other)

Pinnularia spp. Stephanodiscushantzschi

Surirella ovalis Synedra spp.

Chlorophyceae Actinastrumhantzchi (sta-colony.)

Ankistrodesmusspp (needle.30um)

Carteria fornicate(4flagellums)

Chlamydomonasspp (15-20um)

Chorella spp.(3-6um)

Chlorococcumspp (12-18um)

Chlamydomonasspp (15-20um)

Chorella spp.(3-6um)

Cladophoraglomerata

Chodatella spp. Closterium spp Coealastrummicroporum (col)

Cosmariumspp.

Crucigeniatetrapedia (4x4)

Eudorina spp.(colony)

Golekinia spp.(round withspikes)

Mesotaeniumspp

Micractinium sp(col.round.spikes)

Monoraphidiumarcuatum (bigsickle)

Mo.circinale(short fat sickle)

Mo. Contortum(S-sickle) Oocystis sp(colony) O.solitatia (loosecel.rugby ball) Pandorinamorum (colony)

Pediastrumspp (colony)

Pteromonas spp(with sheath)

Scenedesmus spp.(colony)

Schroederiaspp. (needle)

Sphaerocystisspp. (colony)

Staurastrum spp. Tetrastrum spp.(4 cells with spikes)

Tetrastrumregulare (4-corners)

Cryptophyceae Cryptomonasspp.

Dinophyceae Ceratium spp Peridinium spp.

Euglenophyceae Euglena spp Lepocincis spp.

(pear)

Phacus spp. Strombomonas

spp.Trachelomonas



24

confluence with the Orange River near Douglas in the Northern Cape. The Vaal River is

highly regulated through canals and dams. It flows west into the Grootdraai Dam in the

Mpumalanga Province. Grootdraai dam has a total storage capacity of 350 million cubic

metres, a surface area of 39 square kilometres and an average depth of 27 metres. In the

Gauteng Province, it is regulated through the Vaal Dam (Vaal-Barrage Dam). The Vaal Dam

is the fourth largest dam in SA with a catchment area covering 38 505 square kilometres and

a capacity to hold 2575 million cubic metres of water and an average depth of 22,5m. In the

North West Province, it is controlled through the Bloemhof Dam. This dam has a surface

area of 233 square kilometres, an average depth of 18 metres and a total storage capacity of

1.26 billion cubic metres and the longest crest with a length of 4270m.

The majority of the tributaries from the Vaal Dam and downstream are in a critical state of

ecological decline impacted by sewage, industries, urbanization agriculture (DWAF 2006).

Some of the ephemeral tributaries of the Lower Vaal River in the province include the Harts

and Riet Rivers (Figure 8) with water quality of unacceptable standard. The invertebrate

fauna indicate that the ecological state of the Lower Vaal River is in a fair state and is

dominated by Simuliidae, Hydropsychidae, Baetidae, Chironomidae and Oligochaeta

respectively. The poor water quality of the Harts River emanates from the return flows from

the Vaal-Harts irrigation scheme and the irrigation downstream of the Spitskop Dam. These

contribute to the poor water quality in the Lower Vaal River. Poor water quality heightens

water treatment costs for domestic and commercial use, compromises the integrity of

aquatic ecosystems and adversely impacts upon biodiversity The riparian vegetation and

the habitat integrity of the Lower Vaal River are highly modified. The alien Prosopis

glandulosa var. torreyana/velutina and Eucalyptus camaldulensis are found along the river

escarpment near Breyten in the Mpumalanga Province, and then flows southwest to its

banks of Lower Vaal River from Windsorton to Douglas. There is a problem with algae in the

whole of the Lower Vaal River. A long stretch of the river is affected by thick growths of

algae which cover rocks and structures in and around the waters edge.

4.4.2 Ephemeral Rivers

Except for the perennial Orange-Vaal River system, most of the rivers in the province are

dry; some have pools and run only after rains. According to Sekwele (2007) the fish species

occurring in these tributaries are the same as those in the mainstream rivers depending on

the reach at which they join the main rivers (Table 2). In the south-western part of the

4.4.1.2 Vaal River

The Vaal River is the principal perennial tributary to the Orange River within the system, with

a number of small significant tributaries along its length. It originates from the Drakensberg



25

and only a small portion of the north-eastern section falls within the Northern Cape Province (DWAF

2005). The Sak River is the longest ephemeral river in the most isolated northern and western

Figure 8: Rivers of the Northern Cape Province. (Map by Bheki Kunene from Dept of Land Affairs in

Kimberley, 2009).

parts of the semi-arid Karoo region of the province. Its source lies in the higher reaches of

the Nuweveld Mountains, which falls within the Karoo National Park, north of the town of

Beaufort West. It flows into the vast panlands of Brandvlei. During rainy seasons, it flows into theHartbees River which originates from the Van Wyksvlei area. The river is utilized for agricultural

purposes and its banks are encroached by mesquite (Prosopis glandulosa var. torreyana/velutina).

5. Fish checklist of the Northern Cape Province

A total of 51 fish species belonging to 22 families have been recorded in the estuarine and

freshwater. (Benade 1983; Cambray 1984; DENC unpublished data 2002 - 2009; Ecosun 2005;

Harrison 2005; Naesje et al. 2007; Skelton 2001; Seaman and Van As 1998; Whitfield 1998).Table 2 shows the fish species, status and distribution.

province the ephemeral Oorlogskloof River is found. It’s present ecological state is good with

pristine riparian vegetation. The Olifants/Doring River is located in the Western Cape Province



26

Table 2: List of fish species recorded in freshwater and estuarine water in the Northern Cape.

Scientific NameName

Conservation Status / IUCN 2008

Distribution

Anabantidae Sandelia capensis Cape kurper Translocated /Data deficient ODS

Anguillidae Anguilla mossambica Longfin eel Indigenous /Not evaluated LV, LO, ORE

Atherinidae Atherina breviceps Cape silverside Peripheral /Least concern LO, ORE

Austroglanidae

Austroglanis gilli Clanwilliamrock catfish

Indigenous /Vulnerable ODS

Austroglanissclateri

Rock catfish Indigenous, Endemic/Leastconcern

LV, LO, ORE

Carangidae Lichia amia Leervis/Garrick Indigenous /Not evaluated ORE

Centrarchidae Lepomis macrochirus

Bluegill sunfish Alien/Not evaluated Micropterus

dolomieu

Smallmouth

bass

Alien/Not evaluated KR, ODS

Micropterussalmoides

Largemouthbass

Alien/Not evaluated

Micropterus

punctulatusSpotted bass Alien/Not evaluated ODS

Cichlidae Oreochromismossambicus

Mozambiquetilapia

Translocated /Nearthreatened

RR, LO, LV,ODS, ORE

Pseudocrenilabrus

philanderSouthernMouthbrooder

Indigenous /Least concer

Tilapia sparmanni Banded tilapia Indigenous /Least concern

KR, LV, LO,ODS, ORE

Clariidae Clarias gariepinus Sharptoothcatfish

Indigenous /Least concern RR, HR, KR,LV, LO, ODS,

Clinidae Clinus spatulatus Estuary klipfish Peripheral /Endangered

ORE

Clupeidae

Gilchristellaaestuaria

Estuarineround herring

Indigenous /Least concern ORE

Sardinops sagax Sardine Peripheral /Not evaluated ORE

Cyprinidae Barbus anoplus Chubbyhead

barb

Indigenous /Least concern

OR, ODS, SK,SR, BR

Barbus calidus Clanwilliamredfin

Indigenous /Endemic,Vulnerable

ODS

Barbus hospes Namaqua barb Indigenous, Endemic /Leastconcern

LO, ORE

Barbus paludinosus Straightfin barb Indigenous /Least concern

Barbus serra Clanwilliam sawfin Indigenous /Endangered

SK, SR, ORE

Family Common

Threespot barb Indigenous /Not evaluatedBarbus trimaculatus

Labeobarbus Clanwilliam

Yellowfish

Endemic /Vulnerable

ODScapensis

RR, HR, OR,

RR, HR, LV,LO, ORE

RR, LV, LO,

RR, LO, LV, ORE

RR, HR, LV,LO, ORE,

KR, OR,

KR, OK, ODS

KR, ODS, SK

KR, OR, ODS



27

Labeo seeberi Clanwilliamsandfish

Indigenous, Endemic/Critically Endangered

KR, OR, ODS

Labeo umbratus Indigenous, Endemic /Least

concern

RR, LV, LO, SK,SR, BR, ORE

Labeobarbusaeneus

Vaal Orangesmallmouthyellowfish

Indigenous, Endemic /Leastconcern

RR, HR, LV,LO, SK, SR,

Labeobarbus kimberleyensis

Vaal Orangelargemouth Yellowfish

Indigenous, Endemic /Nearthreatened

RR, HR, LV,LO, SK, SR,

Cyprinus carpio Alien /VulnerableLO, OK, SK, ORE

Mesobola brevianalis Indigenous /Least concern LO, ORE

Ctenopharyngodonidella

Alien /Not evaluated LV

Galaxiidae Galaxias zebratus Indigenous /Data Deficient ODSGobiidae Caffrogobius

nudicepsPeripheral /Not evaluated ORE

Caffrogobius caffer Peripheral /Not evaluated ORE

Caffrogobius salthana Commafin goby Peripheral /Not evaluated ORE

Mugilidae Liza richardsonii Southernmullet

Peripheral /Not evaluated LO, ORE

Mugil cephalus Peripheral /Not evaluated ORE

Myxis capensis Freshwater mullet Endemic /Least concern LO, ORE

Poeciliidae Gambusia affinis Alien /Not evaluated

Pomatomidae Pomatomus salthana Peripheral /Not evaluated ORERajidae Raja spp. Skates

Salmonidae Oncorhynchus mykiss Alien /Not evaluated ODS

Sciaenidae Argyrosomusinodorus

Peripheral /Not evaluated ORE

Argyrosomushololepidotus

Peripheral /Endangered

Argyrosomuscoronus

Peripheral /Endangered

Argyrosomus japonicus

Peripheral /Not evaluated

Sparidae

Diplodus cervinus

hottentotus

Zebra

seabream


Lithognathus

lithognathus

White

steenbras

Peripheral /Lower risk,

conservation dependent

ORE

Syngnathidae Syngnathustemminckii

Longsnoutpipefish


Triglidae Chelidonichthyscapensis


ORE-

ORE

Cape gurnard

Labeo capensis Orange Rivermudfish

Endemic /Least concernOK, SK, ORE

KEY: Distribution in the catchments of: LV = Lower Vaal River, LO = Lower Orange River, ORE = OrangeRiver Estuary, OR = Oorlogskloof River, ODS = Olifants-Doring Rivers system, SK = Seekoei River,SR= Sak River, BR = Brak River, KR = Koebee River, RR = Riet River, HR = Harts River.

ORE

OREDusky cob

Kob

Kob

Mild meagre

Rainbow trout

Elf (Blue fish)

Mosquitofish

Flathead mullet

Banded goby

Cape galaxia

Grass carp

River sardine

Carp

Moggel

Barehead goby

RR, HR, LV, LO,

BR, ORE

ORE

RR, HR, LV,

RR,HR, LV, LO

ORE

ORE

LO, ORE



28

6. Conservation Status

The distribution of the fish populations in the Lower Orange-Vaal River system is good in

terms of the fish response assessment index and is dominated by cyprinids. Labeo capensis,

Labeobarbus aeneus, Labeobarbus kimberleyensis and Labeo umbratus are yellowfish species

in the Orange-Vaal River system. Pseudocrenilabrus philander, Tilapia sparmanni and Labeo

capensis are more abundant in the Orange-Vaal River system than Labeobarbus aeneus (Figure 9A)

The distribution of Austroglanis sclateri and L. kimberleyensis in the Orange-Vaal River system

is determined by the availability of suitable habitats and pollution conditions respectively.

A. sclateri was previously recorded as a rare species but the current ICUN evaluation lists it as

a species of least concern. The conservation status of L. kimberleyensis is currently vulnerable.

This species serves as a good indicator of water quality in the province and if the water quality

is poor they also decline in numbers (YWG 2008). Just below the Augrabies waterfalls (a

natural barrier to the movement of fish) there is a high diversity of fish species where Barbus

hospes is confined. B. hospes is endemic to the Lower Orange River below the Augrabies

Falls to Orange River Mouth. The critically endangeredLabeo seeberi , endangered Barbus serra

and vulnerable Labeobarbus capensis are found in the Oorlogskloof River, Koebee River and

north-eastern part of the Olifants/Doring system which falls within the borders of the Northern

Cape (Table 1). The Koebee River, however, has alien fish species like Lepomis macrochirus,

Micropterus dolomieu and Micropterus salmoides (Table 2). A total of 51 fish species from

22 families have been recorded within the waters of Northern Cape. The Orange River

Mouth is inhabited by a total of 35 fish species from 17 families. Out of 35 fish species, 20

are peripheral to the mouth whilst 15 are freshwater fish from the Orange River.

The abundance, diversity and distribution of species of native and alien fish provide

indicators of general environmental quality (Kennard 2005). Flow regimes, modification of

vegetation, increased sediment loads, alteration of bed and banks (including desnagging)

and reduced water quality adversely affects fish populations. Furthermore artificial barriers

negatively affect fish movement, fish health, populations and distribution.

No fish species are known to have become extinct in the waters of the Northern Cape but

with increasing habitat degradation and/or interaction with introduced and alien fish species,

illegal fishing, climate change and water pollution there might be extinctions in the near

future. A survey undertaken by the Department of Water and Environmental Affairs in winter

2008 manifested that the fish in Lower Vaal River was moderately modified with a lower than

expected species richness (C category according to FRAI model) whilst in the Lower Orange

was found to be in a good state (category B according to FRAI model). An additional alien



29

fish species Mosquito fish (Gambusia affinis) was recorded in abundance the in Lower Orange

River near Good House (Unpublished data). The mosquito fish occurs throughout the Lower

Vaal River. The majority of fish species sampled in the Lower Vaal River were infested with

digenean cysts and this can be attributed to poor water quality and the presence of final

(birds) and intermediate hosts (snails and fish).

7. Summary

The Northern Cape is a semi-arid to arid province with its freshwater sources primarily, being

impacted by human activities such as mining, agricultural return flows and urbanisation.

Climate change which is occurring at a slow rate is likely to put pressure on ecosystems

through habitat loss and fragmentation. As global warming increases, species such as

yellowfish which have small populations and slow growth rates are likely to be at high risk.

Global warming and human activities allow invasive weeds and alien species to exploit our

natural resources. The two major rivers run in the province and their fish populations are

dominated by cyprinids. The province has the highest abundance of pans, mostly dominated

by non perennial pans. Poor management of wetlands can also lead to the disappearance of

some of the invertebrates, birds, frogs and plant species.

Figure 9 A-D: A.Vaal-Orange Smallmouth Yellowfish (Labeobarbus aeneus) B. Fish monitoring in the

A B

C D

Lower Vaal River; C. Fish monitoring in the Oorlogskloof River; D. Invertebrates identi-fication in the Harts River.



30

8. Recommendations

Recommendations Responsible Organisation

Develop a better understanding of Northern Capeaquatic ecosystems and the threats to their existence.

Department of Water andEnvironmental Affairs,

Department of MineralResources, Department of Agriculture and Fisheries, LocalFarmers

Strengthen and enforce legal compliance. Department of Water andEnvironmental Affairs,Department of MineralResources, Department of Agriculture and Fisheries

Combat invasive alien species Department of Water and

Environmental Affairs,Department of Agriculture andFisheries, South African NationalBiodiversity Institute

Continue educating communities about sustainable use. Department of Water andEnvironmental Affairs,Department of Agriculture andFisheries, South African NationalBiodiversity Institute,Department of Education

9. Glossary or terminology

Alien: originating outside of its natural known distribution.

Biodiversity: number and variety of living organisms; includes genetic diversity, species

diversity, and ecological diversity.

Biota: the living organisms of a region or system.

Catchment: all the land from the mountain/source to the seashore, drained by a single river and

its tributaries.

Climate: the average, or typical, weather conditions observed over a long period of time for a

given area.

Distribution: the geographic occurrence or range of an organism.

Ecosystem: complex of a community of organisms and its environment functioning as an

ecological unit.

Ephemeral: flow that is periodic.

Endemic: belonging exclusively or confined to a particular place.

Eutrophication: excess nutrient concentration in the water.



31

Fauna: collective term for the animals living in a particular area or period.

Floodplain: area that is flooded periodically by the lateral overflow of rivers.

Flora: plants considered as a group, especially the plants of a particular country, region, or time.

Geology: the scientific study of the earth, including its composition, structure, and physical and

chemical aspects.

Global Warming: the rise in temperature of the earth's atmosphere.

Indigenous: originating and living or occurring naturally in an area or environment.

Pan: a basin or depression in the earth, often containing mud or water.

Peripheral fish: are marine species which are found living in freshwater.

Pollutant: a harmful material that makes an environment less fit for the organisms to occupy it.

Population: group of organisms belonging to the same species which occupy a given area.

Riparian: pertaining to a river bank.

Spring: ground water that flows naturally out of the ground.

Translocated: a species naturally found within Southern Africa but which has been brought

either intentionally or unintentionally by man into catchments in which it was not naturally

distributed

Water quality: the physical, chemical and biological characteristics of water in relationship to a

set of standards.

Wetland: an area where the soil is temporarily or permanently waterlogged.



32

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