Cold Water Kills Tilapia

The fish shown in this picture are tilapia. These warm water fish, native to Africa, cannot tolerate cold water temperatures below 55 degrees. When lake temperatures fall below 55 degrees, then tilapia most often die.

This situation occurs during normal or cold winters and generally lasts a few weeks to a month. Tilapia are found in many Community Fishing Program lakes.

There is no public health risk. Cold water temperatures cause the immune system of tilapia to fail. Consequently, dying tilapia are commonly found covered with a cottony fungus that other, healthy fish can resist.

All other fish such as trout, bass, bluegill and catfish are not affected and are safe to keep and eat. These other fish are healthy and are fully capable of adjusting to seasonal changes in water temperatures.