Fish kill

Common card · No. 498039

The term fish kill, also known as fish die-off, refers to a localized mass die-off of fish populations in a body of water, which may also be associated with more generalized mortality of aquatic life. The most common cause is anoxia in the water, which in turn may be due to factors such as drought, harmful algal bloom, overpopulation, or a sustained increase in water temperature. Infectious diseases and parasites can also lead to fish kill. Toxicity is a real but far less common cause of fish kill, and is often associated with man-made water pollution. Fish kills are often the first visible signs of environmental stress and are usually investigated as a matter of urgency by environmental agencies to determine the cause of the kill. Many fish species have a relatively low tolerance of variations in environmental conditions and their death is often a potent indicator of problems in their environment that may be affecting other animals and plants and may have a direct impact on other uses...

Read on Wikipedia · Image United States Fish and Wildlife Service., Public domain