Lake Tanganyika 'threatened'
Lake Tanganyika, one of the African Great Lakes, has been declared "Threatened Lake of 2017" by a German NGO working with local African partners to improve its sustainability. DW examines the scale of the threat.
Global Nature Fund, an NGO based in southern Germany, has nominated Lake Tanganyika in central Africa as "Threatened Lake of the Year" and together with local partners is calling for sustainable measures to preserve it. Lake Tanganyika is shared between Democratic Republic of Congo, Tanzania, Zambia and Burundi.
Pollution - one threat among many
Pollution, overexploitation and sedimentation are a threat to the diverse species that inhabit this vast African lake. Industrial and domestic waste from cities and villages along the shoreline is discharged untreated into the water. Ferries and even the fishermen themselves, who use oil for generators and night fishing lights, also pollute the lake.
Almost a fifth of the world's freshwater
Lake Tanganyika is 1,470 metres (4823 feet) deep, making it the second deepest lake in the world. It is also the second largest freshwater lake by volume containing almost 17 pecent of the planet's unfrozen fresh water resources. Millions depend on the lake for their livelihood.
Population growth increases burden
Population growth in Burundi, Democratic Republic of the Congo, Tanzania and Zambia is adding to the strain on the Lake Tanganyika's resources. One million people living in the Tanganyika basin depend on the fishing inidustry. They include around 100,000 fishermen. The bigger the population, the more mouths there are to feed.
Famed for biodiversity
Lake Tanganyika contains more than 1,500 plant and animal species, of which 40 percent can't be found anywhere else on the planet. Giant groupers, freshwater jelly fish and spiny eels and the Nile crocodile are just a few examples of the lake's biodiversity.
Overfishing and fewer fish
Lake Tanganyika's natural resources are being overexploited. The lake is being overfished and this has led to a dramatic reduction in the size of catches. Between 1995 and 2011, the number of fishermen increased fourfold, while the total fish stock decreased by a quarter during the same period. The individual fisherman's annual catch went down by 81 percent.
Addressing environmental challenges
Pius Yanda, Professor in Physical Geography, and Director General for Climate Change at the University of Dar Es Salaam says discussion about how to address the challenges likely to threaten the lake's ecological integrity is important. "If people are actively participating in the process of addressing environmental challenges around the lake then that would be for the best".
Climate change and overfishing
In 2016, researchers from the University of Arizona found that fish were becoming more scarce in Lake Tanganyika not just because of overfishing but because of climate change as well. The lake has been warming since the 1800s leading to a decline in algae on which fish feed. But overfishing must still share some of the blame depleted fish stocks, the researchers said.