Of Dead Fish and an Algae Blanket Choking Lake Victoria
As the summer winds down, much of western Lake Victoria stinks. Green algae float on the surface, emitting a pungent smell, akin to smell from rotting fish.
The scum is not just unpleasant. It is dangerous as evidenced by a sudden upsurge of dead fish floating in Africa’s largest freshwater lake.
Harmful algae blooms are a health hazard in all East Africa countries that host the lake.
The lake is among the fresh water lakes in the world, and exceeded in size only by Lake Superior in North America and therefore due to its freshness, it is uniquely vulnerable to algae blooms.
The French Development Agency (AFD) for more than 10 years has awarded 440 million euros (sh56 billion) grant for Monitoring and Sustainable Management of Surface Freshwater Sources in Africa (WaSAf) researchers to study the health dangers, changes in the lake food web, and socioeconomic challenges that arise when these algal blooms produce toxins.
WaSAf is an international research program whose aim is to protect continental surface water systems used for drinking water production in Africa, operates in three countries namely Senegal, Côte d’Ivoire, and Uganda. The programme is co-financed by the French Facility for Global Environment (FFEM).
Mark Olokotum, a researcher at National Fisheries Resources Research Institute, Makerere University, Uganda, observes that like most other water bodies suffering from blooms, the lake is overloaded with nutrients, forming the perfect breeding ground for a bacteria known to poison pets, contaminate drinking water and create oxygen-deprived “dead zones” ushering death aquatic life.
As the blooms spread rapidly, thanks to global warming, the situation is worsening and pose a threat to tourism as well as recreational activities. The blue-green “algae” suffocating the lake is also hurting lives and fish.
According to the Center for Disease Control and Prevention (CDC), exposure to cyanotoxins can causes sore throats, headaches and exhaustion to severe symptoms such as vomiting, pneumonia and liver damage.
Most experts say reducing the quantity of toxic fluids released by farms is the only way to stop the blooms in a lake as large as Lake Victoria.
For more than 10 years, AFD has been supporting several water supply and sanitation projects in the main cities of the Lake shores: Kampala in Uganda, Kisumu in Kenya, Musoma, Bukoba and Mwanza in Tanzania. These projects include infrastructure building as well as technical assistance to Ministries and water utilities.
Present in the East Africa region for more than 20 years, AFD works with cities bordering Lake Victoria to improve access to clean Water and Sanitation for the populations.
Jean-François Humbert, a researcher at WasAF team believes that the project will diagnose how ecosystem changes and human behavioral responses translate into health and economic impacts. He said. “The health, nutritional and socioeconomic insight we gain will be relevant to many modern food systems facing environmental change.”
At present, tracking toxicity requires regular water sampling, something researchers at WaSaf are working on. Their data helps explain how blooms change seasonally, but less is understood about how toxicity fluctuates each day.
“We are aware that we miss lot of dynamics on a day-to-day basis. What we’re trying to do is, by incorporating citizen scientists, collect more data that will allow us to see some of these fine-scale trends in toxin concentrations, which will hopefully allow us to develop the toxin forecast model,” he remarked.
