Fish kills occurring in Nebraska

Recent hot temperatures, followed by several cloudy days, have contributed to the occurrence of fish kills in Nebraska.

The Nebraska Game and Parks Commission recently investigated fish kills at Omaha’s Benson Park Pond and Pioneer Trails Lake near Aurora

Summer fish kills, a natural phenomenon of fish dying off in large numbers during the summer months, often are caused by low dissolved oxygen levels in the water.

One major contributor to these events is a stretch of cloudy days following a stretch of warm sunny weather.

“Under normal conditions, aquatic plants and algae produce oxygen through photosynthesis using sunlight; however, when sunlight is blocked by clouds, oxygen production can drop quickly,” said Aaron Blank, a fisheries biologist for the Nebraska Game and Parks Commission. “Algal blooms can further complicate things as algae can die off much quicker than rooted aquatic vegetation and once they die their decomposition consumes oxygen.”

Fish kills are more prevalent in smaller bodies of water because of their limited volume and the potential for rapid oxygen depletion. Small, shallow ponds with abundant vegetation are particularly susceptible to summer fish kills.

Anglers who observe dead or dying fish should call their nearest Game and Parks office. Find a list of offices at OutdoorNebraska.gov/about/our-locations/.