MENDOTA HEIGHTS, Minn. (WCCO) — The Minnesota Department of Natural Resources says high temperatures may be contributing to fish kills in lakes around the state.
On the shoreline of Rogers Lake, Gary Clausen has found his favorite fishing hole. The Mendota Heights lake is stocked with blue gill, bass and even northern pike.
“The other day, I caught four bass and a northern,” said Clausen.
However, as one of the shallower lakes in the city, it was also the location of a recent fish kill.
“We’re getting a few more reports, yeah,” said Roland Sigurdson, a DNR MinnAqua Education Specialist.
With record setting heat this month, the DNR has seen several fish kills, mostly in the southern part of the state.
“There did seem to be a larger number all at once this year,” said Sigurdson.
High temperatures and little wind can heat water quickly, making it tough for sport fish like northern pike. But warmer water isn’t the only cause. The amount of algae on a lake can also play a huge role in a fish kill.
“At night, when the sun shuts off, the algae start using oxygen rather than make oxygen. The fish, for whatever reason, it doesn’t occur to them they should move,” said Sigurdson.
The impact can range from tens to thousands of fish, which was the case in two lakes near Albert Lea.
“Anytime the public sees dead fish, there’s concern,” said Sigurdson.
Sigurdson says it’s too early to tell if they will see more fish kills due to weather this year. The DNR will take a closer look at the data in the winter.
There are certain things homeowners can do to help prevent one cause of fish kills. Limit the amount of fertilizer on your lawn and clean up grass clippings, so it doesn’t make its way into area lakes.