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All of us, are called upon to promote the conservation of the Okavango River Delta together with its river channels, floodplains, lagoons and all the living organisms that it sustains. The Okavango Delta is undoubtedly the most important wetland in southern Africa.
The Okavango Delta is one of the largest wetlands with the annually flooded area varying from 5,000 to 12, 000 square kilometers and highly variable channel morphology, flow regimes, and ecosystems. Channels within the delta have been classified into upper or primary channels, distributary channels and outlet channels. The delta can also be classified in terms of flow regime and habitat; permanent swamps, seasonal swamps, occasionally flooded areas, and drylands.
The Okavango River enters Botswana from Namibia as a single meandering channel at Mohembo and flows from a north-west to south-east direction. This upper part of the delta is commonly referred to as the Panhandle and it consists of a 10-15 km wide and 150 km long valley. It is critical to note that fault lines determine the flow of water in the Okavango Delta, these lines of faults are: Gumare, Kunyere and Thamalakane Faults.
Where the Okavango River crosses the Gumare fault, it splits into four channels: the Selinda or Mogwegana, flowing north-east into the Linyanti river, the Ngoqa/Mwanachira (east), the Jao/Boro (south-east) and, in the west, the Thaoge. That is, the Okavango River in the Panhandle splits into the western distributary known as the Thaoge River, the river flows to the eastern part as Nqoga River, which eventually becomes Maunachira and Khwai Rivers. Jao River originates from Nqoga River and subsequently separates to form the Boro and Xudum Rivers while Maunachira splits to form Mboroga, Gomoti and Santantadibe Rivers (south east).
The flow patterns of the delta are highly dynamic, due to the build-up of silt in river channels. The main flow is in the Ngoqa–Mwanachira–Mogogelo system. When flows are high, water from the delta reaches the Thamalakane river, which flows through Maun and then into the Boteti River, and the Nhabe and Kunyere rivers, which flow south-west into Lake Ngami. Flow of the Okavango River is therefore partitioned within the delta.
Of the three main distributaries, the Thaoge River in the west terminates in a series of lagoons and extensive floodplains near its upper end. The Boro upstream flows through lagoons and floodplains and is a single more or less confined channel in the downstream discharging into Thamalakane River. The Khwai River in the east has wide permanent flood plains in its middle reaches and discharges to less defined floodplains in the downstream.
The Okavango River and its delta’s mosaic of open water, wetlands and grasslands are home to innumerable species. Some of the species that have been identified include 5 000 insects, 3 000 plants, 540 birds, 164 mammals, 157 reptiles, 80 fish and a countless micro-organism.
As a result of its rich natural resource base, the Okavango River and Delta supports thousands of people who directly or indirectly depend on these natural resources for their socio-economic livelihoods. The rich Okavango ecosystem and its natural resource diversity has partly contributed to the development of human settlements that live along the Okavango River Delta. In addition, the relatively pristine Okavango River Delta has become a destination area for international nature-based tourism which contributes significantly to the economy of Ngamiland District and Botswana as a whole. It is from this background that all of us are called to promote the conservation of the Okavango Delta.