KISUMU, Kenya, Sep 29 — Cage fishermen at Dunga Beach on Lake Victoria are counting heavy losses after thousands of dead fish were discovered floating in the waters on Monday morning, triggering alarm among residents.The mass deaths, which mainly affected cage fish farmers, saw fish estimated at about five months littered across the shoreline, with locals worried about possible contamination.While some fishermen suspect pollution or oxygen depletion in the lake, others fear the incident could point to a larger environmental problem.Developing story…