Researchers have raised alarm over the decline of the health of soda lakes within East Africa as water levels continue to rise.
In a report published in the Current Biology journal this month, researchers from King’s College London and the National Museums of Kenya studied all of the key flamingo-feeding lakes in Ethiopia, Kenya, and Tanzania over two decades and revealed how rising water levels are reducing the birds’ main food source.
The study utilised satellite earth observation for the first time, which revealed how the declining water quality in Kenya and Tanzania’s soda lakes is putting the lesser flamingo at risk of being flushed out of its historic feeding grounds.
“Lesser Flamingos in East Africa are increasingly vulnerable, particularly with increased rainfall predicted for the region under climate change. Without improved lake monitoring and catchment management practices, the highly specialised species found in soda lake ecosystems, including lesser flamingos - could be lost,” lead author Aidan Byrne said.
The report analysed the production of lesser flamingo food within soda East Africa and the results revealed tremendous declines in food production over the 23 years of study and linked this to increases in the surface areas of the lakes over the same period.
The decline in the production, the researchers say, is attributed to the rising water levels within the soda lakes where lesser flamingos thrive in abundance.
Soda lakes in East Africa hold more than three-quarters of the world’s lesser flamingos which feed on the food present in the productive soda lakes of East Africa.
Through the study, researchers were able to see changing food availability across the whole network of lakes, including significant declines in recent years, and how bird numbers decreased as lake surface area increased.
They also identified the lakes the birds might move to in the future.
“Our results highlight the increasing vulnerability of lesser flamingos and other soda lake biodiversity in East Africa, particularly with increased rainfall predicted under climate change,” the report reveals.
The research found rising water levels across the region’s soda lakes were diluting their normally salty and alkaline nature, leading to a decline in food in the lakes. The largest losses in lesser flamingo food occurred in the equatorial Kenyan lakes which are also important tourist lakes including lakes Bogoria, Nakuru, and Elementeita.
Lake Nakuru is one of the most important flamingo-feeding lakes in East Africa, historically supporting over one million birds at a time. The lake increased its surface area by 91 per cent from 2009 to 2022.
