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The Seekoeivlei Ramsar Wetland (27^o 27' to 27^o 41' S; 29^o 34' to 29^o 37' E) is situated in the north-eastern corner of the Free State , in the Memel District. The nearest town is Memel (500 metres SSW) and the wetland stretches from there northwards up to the Mpumalanga border (20 km). The width varies from 200 m to 1 000 m.

The Seekoeivlei Wetland comprises different types of wetlands, namely Seasonal and Intermittent Freshwater Lakes ; Riverine floodplain, including River Flats and seasonally flooded grassland; Seasonal and Intermittent Freshwater marshes and Pools and Peatlands.

This wetland consists of a floodplain drained by the Klip River . The floodplain has numerous small oxbow lakes (ca. 220) which are seasonally flooded. This is a wetland of particular importance as it is the largest one on the southern African Highveld. It performs an outstanding ecological role in that it supports large numbers of local and migratory water birds. Although the wetland does not have a very high plant diversity, it harbours a rich species diversity of waterfowl and other birds associated with water.

Unfortunately, canals dug by farmers drain the wetland. The first canal was dug in 1890 in order to drain parts of the farms Seekoeivlei, Schoon Gesight and Seekoeivleipoort. The marsh bears the Afrikaans name for hippopotamus (Hippopatamus amphibius) (Afrikaans name is seekoei), the last of which was shot in 1894.

This is a wetland of particular importance as it is the largest one on the southern African Highveld. The Seekoeivlei wetland plays a vital role in regulating flow and in maintaining the highest water quality standards of the upper Vaal River , which is the major water source of the highly industrialized and densely populated Gauteng Province . It performs an important ecological role in that it supports large numbers of locally resident as well as migratory waterbirds. Although the wetland does not have a very high plant diversity, it harbours a rich species diversity of waterfowl and other birds associated with water.

This area is used for farming. In areas where the soil is arable, maize and wheat are cultivated. Cattle and sheep are grazed on the typical short dense grassland.

Catchment and downstream areas belong to private landowners.

Consumptive utilization includes cattle grazing and mowing for hay. Non-consumptive utilization includes bird watching and photography.

The vegetation of the area can be classified into (Ref. 3):

Grasslands

The high altitude plateau of the catchment is flat to slightly undulating, and is characterised by Afromontane grasslands. It is dominated by the grasses Themeda triandra and Tristachya leucothrix in the drier bottomland and floodplains.  Themeda triandra-Eragrostis curvula dominated grassland occurs. The herbaceous layer forms a relatively dense cover, often over utilized by livestock. This terrain is particularly vulnerable to the overgrazing and trampling effect of livestock.

Woodland and thicket

These communities are mostly encountered in the catchment on the slopes with a moderate to high relief and along streams.   Woodland and thicket communities represent a Rhus pyroides - Leucosidea sericea low thicket/woodland. This broadly defined vegetation is further divided into woodlands and thickets of moist and dry slopes and is characterized by the tree Leucosidea sericea.

Hygrophilous communities

These communities are restricted to stream banks and streambeds in the wetland. The vegetation can broadly be described as an Eragrostis plana-Agrostis lachnantha wetland community. The major communities in the wetland are classified as follows:

• Fuirena pubescens-Mariscus congestus;

• Berkheya pinnatifida-Eragrostis plana;

• Hyparrhenia hirta-Agrostis lachnantha;

• Eragrostis curvula-Cyperus fastigiatus;

• Senecio inaquidens-Cynodon transvaalensis;

• Diplachna fusca-Cynodon transvaalensis; and

• Schoenoplectus sp.-Cynodon transvaalensis.

The species composition does however vary between the different wetland habitats and by 1996 further study in this regard was needed.

Birds:  Seekoeivlei is a breeding site for the whiskered terns (Chlidonias hybridus), Crowned and Blue cranes (Balearica regulorum and Anthropoides paradisea) and the endangered wattled crane (Bugeranus carunculatus). Waterfowl such as the Spurwinged goose (Plectropterus gambensis), Egyptian goose (Alopochen aegyptiaccus) and Yellowbilled duck (Anas undulata) are also common in the area (Ref. 2).

* Not yet recorded in the reserve, but have been reported from this region, or from similar habitat in the adjacent Volksrust District , Mpumalanga Province.

Mammals:  

As a result of long private ownership of the whole wetland and catchment area, wild animals were driven away by farming practices, or hunted to local extinction, such as the hippopotamus was. Some mammals, such as small antelope, honey badgers (Mellivora capensis) and serval (Felis serval), are sporadically sighted or trapped. Smaller mammals, such as mongooses, rodents and hares, still occur in undisturbed areas

The Seekoeivlei wetlands are situated 1 680 m to 1 700 m above mean sea level.

The wetland is of natural origin and is underlain by sediments of the lower Beaufort and upper Ecca Groups of the Karoo Sequence. Dolerite dykes and sills cut through the sediments. The area is generally flat to slightly undulating, becoming more rugged in the mountainous catchment area south-east of the floodplain and the site.

The soils vary from deep (>500 mm) vertic Rensburg and Arcadia forms to exposed rocky and gravel deposits in the stream beds.  In the marshy areas the soils are seasonally waterlogged.  Peat occurs in some areas and consists of loosely compacted, half decayed plant materials, which consist of up to 97% water.

The catchment area, which is on the southern side of the Memel-Newcastle road, covers a total area of 380 km². The annual rainfall varies from 875 mm/annum to approximately 1 200 mm/annum in the mountainous areas of the catchment. The catchment produces an average annual flow of 46 000 000 m³ of water.

The outflow from the wetland is currently increased by the drainage canals.

Flooding of the wetland only takes place after substantial rains. During drought conditions, the only water available in the entire wetland occurs in the standing pools (2 m deep) in the Klip River, directly north of Memel as well as at a weir to the south of the town.  Two weirs were built upstream from Memel, in the Klip River to supply water to the town and also act as sediment traps.

Precipitation:  The wetland is situated in the summer rainfall zone with a mean annual rainfall of 720 mm (Frankfort/Standerton area).  In the catchment area the annual rainfall can be as high as 1 200 mm/annum.  Precipitation is mostly in the form of thunderstorms between November and March.  Mid-summer droughts occur towards the end of December to the middle of January.  The annual rainfall varies from 875 mm/annum to approximately 1 200 mm/annum in the mountainous areas of the catchment.

Frost occurs commonly during winter and snow has been recorded on several occasions.

Temperature:  The maximum mean monthly temperatures for Frankfort and Standerton are 28.3°C and 27.3°C respectively.  The minimum mean monthly temperatures for these two stations are -3.7°C and -2.1°C respectively.

The most obvious and immediate threats to the site include the following:

• Uncontrolled burning of the vegetation which results from fires spreading into the reserve from adjacent grasslands.

• Inappropriate management practices.

• Invasion of exotic plants such as the black wattle (Acacia mearnsii) which was introduced into the area for the production of tannin. This species is used in the hide industry in KwaZulu-Natal . Another exotic invasive plant species is the Scottish thistle (Cirsium vulgare) which was probably introduced as a garden plant, or accidentally, during the previous century.

In the catchment area inappropriate farming practices, such as increasing use of fertilizer, as well as increasing erosion caused by overgrazing and trampling by cattle, will have a severe impact on the water quality in the wetland and as such pose threats to the wetland. Siltation will become a problem in the future      (Ref. 1).