Three countries — Angola, Botswana and Namibia — share the precious freshwater resources of the Cubango-Okavango River Basin, an oasis in the heart of the Kalahari Desert. The basin floods seasonally, swelling to twice its size and sustaining communities and wildlife across this arid region. As many ecosystems around the world struggle to maintain, or restore, their biodiversity, the Okavango Delta stands out not only as an ecological haven, but for its sheer scope — 1.2 million hectares (3 mill