Lake Tanganyika fisheries declining from global warming

Typography

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 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.

However, large-scale commercial fishing did not begin on Lake Tanganyika until the 1950s.

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."

Continue reading at EurekAlert!

Image: Lake Tanganyika coastline Mahale Mountains, Tanzania via Andrew Cohen, University of Arizona at Tucson; National Science Foundation