PROVIDENCE, R.I. (WPRI) — Sightings of dead fish in Providence rivers are not concerning, the R.I. Department of Environmental Management (DEM) Division of Marine Fisheries said Friday.
The DEM told 12 News they received several reports of dead fish in the Providence and Seekonk rivers and have confirmed they were “natural mortality events” of Atlantic menhaden.
DEM spokesperson Mike Healey said the phenomenon is known as “school-induced hypoxia”—which means the concentration of oxygen within a school of fish changes.
“The dissolved oxygen (DO) of these waters is typically high this time of year, and with hundreds of thousands of fish in a small, localized section of shallow water, they can deplete the DO in the immediate vicinity, which leads to some mortality,” Healey explained.
According to the DEM, the mortality rate is low and live fish were observed in the area.
Atlantic menhaden are known to be a sensitive species, Healey said.
“A high concentration of fish being chased into shallow waters by predators can often lead to stressed fish and localized DO depletion,” Healey added.