Country/territory: Namibia
IBA criteria met: A1, A3, A4i (1998)
For more information about IBA criteria, please click here
Area: 468,000 hectares (4,680.00 km2)
Site description (2001 baseline)
Located in the eastern Caprivi bulge, this wetland system lies on Namibia’s international border with Botswana, Zambia and Zimbabwe, and stretches from the Kwando river in the west, to the Zimbabwean border-post at Kazungula in the east. It is Namibia’s largest single permanent wetland and is fed by two of the country’s five perennial rivers. The area is divided into five geographically distinct zones: the Upper Kwando (137 km²), Lower Kwando and Linyanti Swamp (3,830 km²), the ephemeral Lake Liambezi (406 km²), the Chobe river and marsh (311 km²) and the Zambezi flood-plains (1,800 km²).
The area is topographically featureless and almost completely flat—a key determinant in the unusual hydrological regime. Under flood conditions, the Kwando is essentially linked to the Zambezi, with water flowing from the Kwando into the Linyanti Swamp, about 10% of which finally reaches Lake Liambezi. This water is, however, insufficient to keep the lake level from dropping. When full, Lake Liambezi has an outlet to the Chobe river, which subsequently joins the Zambezi at Kazungula. When the Zambezi is in flood, the flow is reversed and water is pushed up the Chobe to Liambezi. Lake Liambezi and the flood-plain zone are thus only intermittently inundated, while the Zambezi, Kwando, Linyanti Swamp and Chobe Marsh are permanent features. The abrupt change in the direction of the Kwando river as it merges into the Linyanti system is due to the extensive geological faulting present in the area. Floodwaters channel down the Kwando between June and August and then swing north-east along the Chobe fault into the Linyanti Swamp. It may take up to six months for water to percolate through the
Phragmites/
Cyperus dominated reed-swamp, as less than one third of the area is open water. By 1997 Lake Liambezi was a dry lakebed, completely overgrown and partly farmed; these long-term dry/wet periods appear to be cyclical.
The Chobe Marsh, into which the Linyanti Swamp and Lake Liambezi drain when full, is more usually inundated by water backing up along the Chobe from the Zambezi river. The Zambezi floods typically last 4–6 weeks in March–April, before subsiding back into side channels and the main Chobe/Zambezi channels. However, the lower-lying flood-plains remain inundated for longer periods, and support vast beds of papyrus and reed in a maze of small channels and islands. The climate of the region can be divided into two distinct seasons—a dry season between April and November, and a shorter wet season which stretches from the end of November to late March/early April. This is the wettest place in Namibia with rainfall averaging 740 mm per year, and sometimes exceeding 1,000 mm per year. The monthly average maximum temperature is about 30°C.
The area is surrounded by pristine riparian fringes, which are extremely rare in Namibia, as they have mostly been destroyed by human activity. The vegetation is dominated by trees of
Lonchocarpus,
Garcinia,
Syzygium and
Diospyros. The flood-plain consists of reedbeds, swamps, open flooded grasslands and papyrus. Two conspicuous species on the edge of the flood-plain are the wild date-palm
Phoenix and baobab
Adansonia.
Key biodiversity
See Box and Table 3 for key species. East Caprivi as a whole, and its wetlands in particular, holds one of the richest diversities of bird species anywhere in Namibia. The high diversity arises from a combination of wetland and tropical (passerine) species extending into this region. The most important features of this system are the swampy areas and flood-plains, which are important breeding habitat for wetland birds. These and other wetland species include Egretta vinaceigula, Grus carunculatus, Ardeola rufiventris, Ephippiorhynchus senegalensis, Microparra capensis, Vanellus albiceps, V. crassirostris, Glareola pratincola, Macronyx ameliae and Circus pygargus.
Non-bird biodiversity: Threatened mammals occurring here include Lycaon pictus (EN) and thousands of Loxodonta africana (EN).
Recommended citation
BirdLife International (2024) Important Bird Area factsheet: Eastern Caprivi wetlands (Namibia). Downloaded from
https://datazone.birdlife.org/site/factsheet/eastern-caprivi-wetlands-iba-namibia on 22/12/2024.
