The Okavango Wetland Bird Project conducts an annual survey which aims to record the distribution, abundance and breeding activity of all wetland birds along a 288km mokoro(dug-out canoe)-based transect of the Okavango Delta. The project will run over a period of 9 years. A hydroelectric weir in the Caprivi Strip, 16 dam refurbishments in the Angolan catchment, mining developments, and agricultural schemes along the Okavango River are being planned.
We urgently need to establish the potential impacts of these developments to the functioning of this wilderness area, more specifically the breeding of wetland birds in the region. We are doing this expedition each year to create a benchmark for the activity of wetland birds during these annual floods in inaccessible areas. In 2010, we embarked on the first of nine expeditions across the Okavango Delta, which coincided with the largest flood in recorded history. Our first survey coincided with the end of this flood and established the first benchmark for the reaction of healthy wetland bird populations to the flood regime of the Okavango Delta.
Over the period of 9 years, we will cover all three months of the annual flood three times. In 2010 the survey was conducted in September. Then in 2011we conducted the survey in August. In 2012 we completed the transect in July. This year, 2013 is the 4th year of 9, we are repeating September and are excited to compare results between significantly different annual floods.
During expeditions, we photograph, describe and map all changes in habitat type for correlation with the activity of all wetland birds that we encounter. Expedition members also take detailed notes on water quality, frog diversity, and the distribution of crocodiles and hippos. The 14-20 days taken to traverse the Okavango Delta on a mokoro are grueling (both mentally and physically), and we hope that our commitment every year to undertake these expeditions makes a strong statement about the value of this wetland wilderness.
Aims: The primary aim of the Okavango Wetland Birds Project (OWBP) is to record and map the distribution, abundance and breeding activity of wetland birds in areas that are inaccessible without a mokoro to establish a benchmark for their interactions with the annual flood. We intend to demonstrate the importance of the Okavango Delta as a keystone breeding ground for numerous wetland bird species in southern Africa, and draw attention to the lobby for designation as a UNESCO World Heritage Site.
Justification: The Okavango Delta is Africa’s third largest inland delta, after the Sudd swamps in southern Sudan and Niger Delta in west Africa, on the African continent, and the Okavango River is, as yet, free of significant impoundments (e.g. dams and weirs) all the way up to the Cuito and Cubango sub-catchments in the Angolan highlands. This is largely due to civil war and unrest in the catchment and the reluctance of the Botswana government to unnecessarily disturb this sensitive wetland ecosystem. There is no doubt that the Okavango Delta is one of Africa’s most valuable natural wonders, which is visible from space and represents the largest unfenced, uninhabited wilderness areas on the continent.
Potential Threats: In recent years, however, several development strategies have been put forward for the Kavango Basin, which spans Namibia, Angola and Botswana. These proposals have put forward the refurbishment of 16 dams in the Angolan catchment that were destroyed during the 25-year civil war, a hydroelectric weir at Popa Falls on the Okavango River in the Caprivi Strip (Namibia), and the inauguration of an irrigation scheme to support can sugar farming in the “panhandle” of the Okavango Delta. All of these developments threaten the flow of water and sediment into the Okavango Delta, thus threatening the functioning of this wetland ecosystem. If sufficient water and sediment do not enter the Okavango Delta each year, we won’t see channels switching direction or new floodplains establishing themselves. Both these functions support the diversity of habitat types that are characteristic of the Okavango and support the stunning biodiversity found in the system.
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