Fisherfolks living around lake Victoria are now living in fear that their economic backbone which is fishing could wipe out and be left with no livelihoods following massive fish deaths reported on Lake Victoria recently.
According to the fisheries experts, most of these dead fish are not linked to poisoning as alleged by a section of the population.
Speaking to Radio lake Victoria radio an environmental expert working with Osienala(Friends of Lake Victoria) Dr. Godfrey Ogonda attributed this phenomenon to the ever toxic effluent being discharged into lake Victoria making it unhabitable for marine life, Dr. Ogonda adds that the situation could get worse if the lake Basin countries do not put in place urgent interventions faster. He pointed out the lake backflow which he noted could be as a result of climate change and a high level of siltation in the lake would be more damaging if not mitigated soon. Dr. Ogonda reiterated that as OSIENALA (Friends of Lake Victoria), they’ve been carrying out environmental conservation interventions which need to be scaled up on the Tanzanian and Ugandan side of the lake if any long-term solution is to be found.
For the past two consecutive weeks, residents and fishermen have reported an unusual phenomenon of dead fish floating on water or being washed ashore.
Residents and fisheries along Lake Victoria told Radio lake Victoria 92.1FM last week that the most endangered species are Nile Perch and Tilapia.
“The water changes according to the temperature and algae [level]. The fish dies and floats on top of the water. But this time, the volume of fish dying is too much,” said 38-year-old Monica Awiti.
Our journalists during a visit witnessed a number of residents along the beaches on side of the lake harvesting the decaying fish and either deep-frying or drying them in the sun before the sale.
“We do not know what is happening. We have taken samples to the laboratory … to analyze and find out what is happening (to the fish in the lake). It could be a natural occurrence, but we also suspect poisoning,” says one of the specialists.
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The impact of the consumption of such fish on human life also remains unknown.
The rising mid-morning sun cast stretched shadows of returning fishermen. The group of fishermen had spent Monday night on the waters but were not as lucky. After retrieving loads of nets, they counted only seven Nile Perch. A kilogram of Nile Perch is at Kshs 300. One of the seven fish was visibly rotten but because it was big, the fishermen sold it at a discounted rate.
At another landing site, about one kilometer away, a middle-aged man, was salting, drying, and smoking dead fish. He hung some on his shack house made of polythene and tarpaulins.
Another woman fanned the wood fire to smoke fish placed on rusty iron sheets above the logs.
“If you are not buying [fish], then leave us alone,” a resident said as he straddled to join colleagues at a drinking joint in a nearby banana garden.
Mr. Fred Onyango, 54, who has been a fisherman for four decades, said the trend of fish dying in the lake is “seasonal”.
“When the hot season begins, many (fish) die. This is not the first time it is happening,” he said.
Ms. Anosiyata said: “This time even the young fish (fry) are dying. We are wondering what is causing it.”
Whereas the government reported an increase in fish stock since the Uganda People’s Defence Forces began the clampdown on illegal fishing, alongside growing cage fish farming, Bank of Uganda statistics released in September 2020 showed Uganda’s exports had declined by more than 5,000 tonnes. This resulted in Shs124b fish export revenue shortfall.
“I do not think the issue is with the temperatures because the survival rate of the fish in the water cannot be related to the temperature in the water,” Mr. George William Omony, a senior meteorologist at the Uganda National Meteorological Authority, said.
He added that fish did not die in masses when Uganda registered the highest temperatures of 38 degrees Celsius in 2019 on Lake Victoria.
Lake Victoria is a freshwater body shared by Uganda, Kenya, and Tanzania.
In Kenya’s Homa Bay County at the shores of the lake, the Beach Management Unit chairperson, Mr. Edward Oremo, confirmed on Wednesday last week that they had received reports from fishermen that they had seen some dead fish on the lake.
He added that some of the affected areas were in Kiwa and Nyandiwa beaches in Suba Sub-county, Homa Bay County. He could not confirm whether more are still dying.
Communities living in and around the shores of Lake Victoria have recently been concerned by the growing number of dead fish, especially Nile Perch, being washed ashore.
The dead fish are not only an eyesore but also emit an offensive odor as the decomposition occurs. However, preliminary investigations have ruled out the possibility of poison as the cause of the deaths of the fish.
The occurrence has been attributed to a drop in oxygen levels. Nile perch is a species of fish known to be sensitive to low oxygen levels- (below 2mgl).
As a result of the recent flooding and rising water levels, large masses of weeds were submerged and sunk into the lake bed. These weeds use up oxygen as they rot from within the lake hence a drop in the oxygen levels.
Also, the recent strong winds around the Lake Victoria basin have heightened lake overturn; a phenomenon that causes water from the bottom of the lake that is low in oxygen, to come up and mix with upper layers, where fish live; leading to a reduction in oxygen, hence the death of fish. This is not the first time large scale fish deaths are occurring on Lake Victoria; Fishing communities have always referred to this situation as “Kaliro” and it occurs periodically.
Communities living around the lake are advised to bury the dead fish to contain the pungent smell; as further research and studies are undertaken by all stakeholders including, NEMA, MAAIF, Communities, developers.