08-16-2007, 06:10 PM
Iowa Fish Kill Appears Natural
A small fish kill in the North River near Stuart, Iowa, appears to have occurred due to natural causes, according to state fisheries biologists.
A citizen reported the fish kill to the Department of Natural Resources, and biologists found about 50 dead chubs, sunfish, minnows and bullheads. The kill was contained in a one-mile stretch of stream located south of Stuart and Menlo in Adair County.
DNR staff found mats of algae and brown water in the stream, indicating an algae die-off. When algae die in large numbers, water can turn brown and oxygen levels can fall. Low oxygen levels can be toxic to fish and other aquatic life.
High water temperatures and low water flows are already stressing fish in many parts of the state, making them more vulnerable when oxygen levels drop.
A small fish kill in the North River near Stuart, Iowa, appears to have occurred due to natural causes, according to state fisheries biologists.
A citizen reported the fish kill to the Department of Natural Resources, and biologists found about 50 dead chubs, sunfish, minnows and bullheads. The kill was contained in a one-mile stretch of stream located south of Stuart and Menlo in Adair County.
DNR staff found mats of algae and brown water in the stream, indicating an algae die-off. When algae die in large numbers, water can turn brown and oxygen levels can fall. Low oxygen levels can be toxic to fish and other aquatic life.
High water temperatures and low water flows are already stressing fish in many parts of the state, making them more vulnerable when oxygen levels drop.