The influence of wetlands, decaying organic matter, and stirring by wildlife on the dissolved oxygen concentration in eutrophicated water holes in the Seronera River, Serengeti National Park, Tanzania

The dissolved oxygen concentration (DO) was sampled during a diurnal cycle in three water holes heavily used by wildlife and with distinctive biological features along the Seronera River. The DO fluctuated widely (by up to 11.5 mg l−1) as a function of time, mechanical stirring and aeration by animals, and the presence of fringing wetlands. The DO cycle was successfully modeled (within 0.3 mg l−1) by assuming that the four dominant processes were photosynthesis and respiration by algae near the surface, trapping by wetlands, decomposition of dead organic matter on the bottom, and stirring/aeration by hippos. The rate of DO decline from the decay of dead organic matter was equal to the rate of DO removal by algal respiration at night

Papyrus wetlands a lunar-modulated refuge for aquatic fauna

A field study was undertaken of the use of papyrus (Cyperus papyrus) wetlands fringing Rubondo Island, Lake Victoria, Tanzania, as a refuge from predators by freshwater shrimps (Caridina nilotica) and tilapia (Oreochromis niloticus) larvae. During the full moon nights, fish larvae took refuge more than 5 m in the papyrus and did not venture out into the lake, while they ventured into fringing lake waters during moonless nights. The freshwater shrimps and lake flies (Chaoborus sp.) did not migrate with the moon. This fauna took refuge in the papyrus wetlands even though the dissolved oxygen concentration was as low as 0.4 ppm (<5% of saturation)

The Serengeti will die if Kenya dams the Mara River

[Extract] The Serengeti ecosystem hosts the annual wildlife migration of up to 2 million animals (mainly wildebeests, zebras and other species of the plains). It is a World Heritage site, important to the Tanzania tourism industry, and an ecosystem living laboratory. It comprises the Serengeti National Park, the Masai Mara National Reserve in Kenya, and several Conservation, Game, and Wildlife Management areas. The Serengeti has one perennial river, the Mara, which is the only source of water for migrating wildlife in a drought year. The Mara River is formed by the confluence of the Amala and Nyangores Rivers, which drain the Mau forest in the Kenyan highlands; it is a transboundary river shared between Kenya upstream and Tanzania downstream

Ecohydrology-based planning as a solution to address an emerging water crisis in the Serengeti ecosystem and Lake Victoria

[Extract] The Serengeti ecosystem is often taken to be the 25000 km2 animal migration area (Figure 1a). This includes the 14,763 km2 Serengeti National Park (SNP), the Masai Mara Reserve in Kenya, and a number of game controlled areas that form a buffer zones, principally the Maswa, Ngorongoro, Loliondo, Ikorongo, Grumeti, and the Speke Gulf Game Controlled Area (SGGCA) that, although tiny (95 km2), is potentially important because, if human encroachment was removed, it would provide access for wildlife to the permanent waters of Lake Victoria (Figure I b). However this definition of the ecosystem ignores the hydrology. The Serengeti ecosystem has only one perennial river, the Mara River. The Mara River, together with a few scattered springs in the northern region of the SNP, is the only source of water for migrating wildlife in the dry season in a drought year. Thus the source of Mara River water in the dry season, namely the Mau forest in Kenya's highlands, is also part of the Serengeti ecosystem even if the migrating animals do not migrate to that area (Gereta et al., 2002 and 2009)

Are Tanzanian National Parks affected by the water crisis? Findings and ecohydrology solutions

Availability of water for wildlife in some of the National Parks in Tanzania has been hampered by several factors including the effect of climate change and anthropogenic factors due to the fact that most of the water catchments are outside the national parks. In order to ensure the survival of the National Parks, TANAPA, which is a Parastatal Organization mandated to manage the National Parks, has taken proactive initiatives and actions to tackle the water crisis in its National Parks, principally the Serengeti, Tarangire, Ruaha, Katavi, Rubondo, Saadani, Arusha and Kilimanjaro National Parks. These initiatives and actions have followed the ecohydrology guidelines for water management and they varied from Park to Park according to the local conditions. There are limits to what TANAPA can achieve by itself to save its National Parks from the water crisis, because TANAPA has no control on activities outside the Parks. For those water issues TANAPA has communicated its findings and recommendations to the government and stakeholders, and the resolution, or otherwise, of these issues requires state governance as well as in some cases cooperation between the East African countries

Restoring the perennial Great Ruaha River using ecohydrology, engineering and governance methods in Tanzania

The Great Ruaha River (GRR) in Tanzania was perennial before 1993. Its source, the Usangu wetlands, was also perennial. Since then, the GRR has started drying out during the dry season, with a trend towards earlier and longer periods of drying. This drying process degrades the surrounding ecosystems along the entire length of the GRR, including the Ruaha National Park (RNP) and impacts human livelihoods throughout its course; it also impairs the economy of Tanzania through reduced hydropower generation at the Mtera and Kidatu power plants. The Usangu wetlands dried up in 2000, 2002 and 2005 during the dry season and its areal extent has been shrinking. Intensive livestock grazing and both dry and wet season irrigated agriculture in the Usangu wetlands, were the main reasons for this water crisis. In 2006, the Government of Tanzania moved to address the crisis by removing livestock from the Usangu wetlands, attempting to regulate water use in the GRR catchment and expanding the RNP to include the Usangu wetlands