Private pond owners should be wary of fish possibly succumbing to winterkill.
A prolonged winter and recent frigid weather are keeping ponds covered with snow and ice well into March, creating conditions for a winterkill, said Jeff Blaser, private waters specialist with the Nebraska Game and Parks Commission.
Winterkills typically occur in small, shallow ponds with abundant aquatic vegetation. Snow and ice covering a pond prevent the water from exchanging oxygen with the air. Excessive snow and thick ice allows very little sunlight penetration, so plants are not able to produce enough oxygen. If excessive snow cover persists, the plants die and subsequent decomposition, along with respiration by various aquatic organisms, can completely deplete the oxygen, resulting in a fish kill.
Blaser recommends pond owners take stock of their waters at ice-out. “Depending on the size of the pond, the presence of 40 or 50 dead fish would not indicate a large winterkill; however, thousands of dead fish of various species and sizes would be evidence of a major die-off event.”
Blaser suggests owners check for fish (visually and angling) following ice-out to help determine the status of the fish populations. The findings from these actions could indicate a pond is a candidate for restocking
Pond owners can contact Blaser at 402-471-5435 for management suggestions if they had a major fish kill.
Information provided by Nebraska Game and Parks Commission.