"Kenya Marine and Fisheries Research Institute conducted a study that revealed the fish died due to inadequate supply of oxygen when organic matter is decomposing in the lake," he said, adding that reports of fish dying in the lake started one month ago.
"During heavy rains, floods dump a lot of organic matter in the lake. When the organic matter decomposes, it uses oxygen which leads to competition for oxygen with fish," Okoth said.
The Director said the remedy for the problem is to avoid cutting vegetation along the lake shore.
"The vegetation prevents entry of too much organic matter into the lake. This is a natural phenomenon which can only be prevented by conserving vegetation along the shores of Lake Victoria," Okoth said.
Further, the dumping of waste into the lake also contributes to the death of fish.
Homa Bay County Beach Management Network Chairman Edward Oremo urged the government to conduct research that can rescue the ecosystem of Lake Victoria.
Oremo said more than 30 beaches in the county have been affected, adding that the water from the lake has turned green.
"In most beaches, the water has turned green, which has affected the fish survival. I appeal to the government to dispatch researchers who can discover a long-term solution to this problem," Oremo said.
At Kamolo beach, Patrick Odhiambo is one of the farmers counting losses estimated at Sh4million.
He was rearing fish in four cages where each cage had 5,000 fish.
Upon maturity, each fish is sold at Sh200. This means he was expecting about Sh1 million from each cage.
"The fish was almost mature and I was planning to begin harvesting this December. This is a serious loss that I have incurred," Odhiambo said.
The chairman of fishermen at Obaria Beach Management Unit, Dan Rege, said farmers with more than 20 cages were the most affected, revealing the fish had to be thrown away to avoid contamination.
Rege urged the government to come up with a solution that can prevent the deaths of the fish.
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"I appeal to the government to come up with a solution that can prevent these deaths," said Rege.
A similar incident occurred a few weeks ago in Lake Victoria near Ndhuru and Kananga beaches in Mbita and Homa Bay sub-counties.
Ndhuru Beach Management Unit Chairman John Ogweno said the death of fish has affected many cage fish farmers in the area.