Wherever you go these days there is only one thing that people are talking about and that is the torrid temperatures and the lack of precipitation. Another thing that people should realize is that the hot weather and little or no rain are affecting most things in the outdoors and nature. Lawns, plants, gardens, trees, bushes, and most growing vegetation is either dying or under severe stress. One thing that most people don’t think about is the thousands of fish that are dying in Wisconsin, Minnesota, and the Dakota’s with water temperatures in the 90’s and a blazing sun pounding lakes and rivers throughout the Midwest. Combine these temperatures with a lack of oxygen and you have a setting for dying fish especially in lakes that are less than 10 feet deep. In lakes that have good depth, fish can flee the hot water for cooler water in the deeper depths. I’ve had DNR from numerous states say that they haven’t seen so much heat and lack of water since the 1930’s and the “Dust Bowl Days.”
The past two weeks, I’ve talked with DNR personnel and fisherman throughout the Upper Midwest checking on the fishing, water conditions, and the number of fish kills. Temperatures have cracked the 100 degree mark in many locations in Wisconsin, Minnesota, North Dakota, and South Dakota. There have been fish kills in the shallow waters of the Upper Lakes in the Lake Winnebago system with northern pike taking a real beating! The James River in southeast North Dakota and northeast South Dakota has been hit hard by the weather. Locally, there was a northern pike fish kill on Lake Wisconsin about a week ago with many “nice” dead and floating pike on the lake.
Northern pike are especially vulnerable to this hot weather because they are a fish better suited for cooler water and they are dying on waters where they don’t have any deeper water to escape to and cool themselves in. Kurt Welke, the DNR Fisheries Manager for Dane County, said that these fish kills are “normal” occurrences during summer’s hot weather and the happening are part of nature’s continuing cycle. This is not the first time that we have had fish kills, but it may turn out to be one of the worst. One of the worst summer’s in recent decades was in 1988 and we have had lesser kills since then. But, the many fish species are part of nature and the good and bad seem to work things out in the long run. We all know that this is a difficult time, but I pray that we will return to normal weather and all of nature that has been stressed will live and flourish again.
Jack Lauer, the Minnesota Regional Fisheries Manager for New Ulm, Minnesota said that fish kills are “normal’ during hotter summers and that we’ll have more with hot weather predicted for the next few weeks. The lakes that will be affected are those with depths less than 8-10 feet. Lauer said that warmer water holds less oxygen. Lauer also said that high algae levels common in summer also deplete oxygen levels and so does competition from hardier carp and bullheads. It’s lucky that enough fish survive these die-offs to restock and replenish the affected lakes.
In Wisconsin, DNR Biologist, Ryan Koenig’s, said that they started seeing larger northern pike dying in shallow lakes and the Lacrosse River Marsh last week when water temperatures hit the upper 80’s and lower 90’s. Biologists have seen carp, perch, bluegill, largemouth bass, pike, and gizzard shad in the die-off. Some of the dead fish could be attributed to the blue-green algae, but most are from the high water temperatures. The worst part of the die-off is that many of the fish were large northern pike from 20 to 40 inches and even bigger. Some of these pike were at least 15 years old.
The fish kill on the James River in the Dakota’s killed thousands of pike which is another sad sight to see. The pike population was at a record high with ideal spawning conditions recently and now this kill is a disaster.
Wisconsin has also seen its share of dying fish with five recent kills reported to the DNR. Scott Stewart, the DNR Fisheries Supervisor in southern Wisconsin, said the same as other states have said. The long period of hot weather and lack of precipitation has created low water and oxygen levels in many waters. According to Stewart, as water levels go up, the water cannot hold the oxygen that the fish need. The five fish kills reported are on the Rock River in Dodge County, upstream from the Horicon Dam, near Hutisford and Lake Sinissippi, Beckman Mill Pond in Green County, on the Yahara River below Lake Kegonsa in Dane County, and on Lake Wisconsin.
These fish kills are a natural occurrence with hot weather and lack of oxygen which much of the country has been experiencing. There also have been fish kills in Delaware and Kentucky too, so this is a national crisis.
If you see a number of dead or dying fish call the DNR at 1-800- 847-9367. The sooner that the DNR hears of a fish kill the better!