Global Warming Causing Declines of Fisheries in Lake Tanganyika
The people in the small fishing village along the shore of Lake Tanganyika rely heavily on the small sardines from the lake for their own food and also probably sell them dried in a nearby market. Credit: Andrew S. Cohen/ University of Arizona
The decrease in fishery productivity in Lake Tanganyika since the 1950s is a consequence of global warming rather than just overfishing,according to a new report. The lake was becoming warmer at the same time in the 1800s that the abundance of fish began declining and the lake’s algae started decreasing. Large-scale commercial fishing did not begin on Lake Tanganyika until the 1950s.
The decrease in fishery productivity in Lake Tanganyika since the 1950s is a consequence of global warming rather than just overfishing, according to a new report from an international team led by a University of Arizona geoscientist.
The lake was becoming warmer at the same time in the 1800s the abundance of fish began declining, the team found. The lake’s algae — fish food — also started decreasing at that time.
The new finding helps illuminate why the lake’s fisheries are foundering, said study leader Andrew S. Cohen, a UA Distinguished Professor of Geosciences.
“Some people say the problem for the Lake Tanganyika fishery is ‘too many fishing boats,’ but our work shows the decline in fish has been going on since the 19th century,” Cohen said. “We can see this decline in the numbers of fossil fish going down in parallel with the rise in water temperature.”