By Mike Kruzman / news@whmi.com


As lakes and ponds around Livingston County thaw in the warmer weather, state environmental officials are reminding and cautioning residents about what could be a startling sight.

The Michigan Department of Natural Resources advises that after ice and snow cover melts away for the season, that it is more likely for people to discover dead fish or other aquatic animals like turtles, frogs, toads, or crayfish.

DNR Fisheries Division research manager Gary Whelan said this is known as “winterkill” and may be common in shallow lakes, ponds, streams and canals. Shallow lakes with excess aquatic vegetation and soft bottoms are more prone to the problem, particularly when a deep snowpack reduces sunlight for the plants. Whelan said winterkill begins with distressed fish gasping for air at holes in the ice and often ends with large numbers of dead fish that bloat as the water warms. This could take up to a month to show. Some fish and other deceased aquatic animals may appear fuzzy because of a secondary infection by fungus, the fungus was not the cause of death. Whelan said the fish actually die from suffocation caused by a lack of dissolved oxygen under the ice.

These kills, though, are localized and typically do not affect the overall health of the fish population or fishing quality.

For more information on fish kills in Michigan, visit www.Michigan.gov/Fishing. Report fish kills at www.Michigan.gov/EyesInTheField to help the DNR manage the state’s aquatic resources.