More Information Dead and dying fish are an ugly sight.
Truth is, most species of fish are relatively short-lived and have a high rate of mortality.
Fortunately, the deaths are usually spread-out over the year and are rarely observed or become a problem except when concentrated as a fish kill. Only a fraction of the dead fish are ever observed because many decompose on the bottom or are eaten by scavengers such as turtles and crayfish. Most of the time, fish kills are due to natural causes over which we have no control, such as weather. Only occasionally is death directly related to pollution or improper use of herbicides or other chemicals. Winterkill Winterkill is the most common type of fish kill.