Mysterious Fish Die-Off Reported at Missouri’s Mark Twain Lake

There are few things quite as unsettling as going out for a day at the lake and encountering a huge amount of dead fish in the water. That's exactly what's just happened at Mark Twain Lake and Missouri officials are trying to figure out why.

This new report from the Missouri Department of Conservation says they have been made aware of a massive fish die-off of walleye at Ray Behrens, Spalding, and Dam portions of Mark Twain Lake. After an investigation, here's what they say they've found:

"In this particular instance, the lake has experienced extreme stratification due to consistently warm weather over the past several weeks. Oxygen is only present 13-feet deep, and the water has reached 82 degrees Fahrenheit. Walleye thrive at temperatures between 55 and 70 degrees Fahrenheit and prefer water up to 30-feet deep at this time of year. "

The conclusion is that the walleye in these areas of Mark Twain Lake are having to make a choice between two very poor options - water that's too hot or water that lacks oxygen. This is the long way of saying that the recent fish kill at Mark Twain Lake was not due to some toxic chemical being introduced into the ecosystem, but a side effect of the ongoing heat wave which is driving water temperatures up.

At the end of the day, this is a natural and not uncommon part of the circle of life at Mark Twain Lake. It's not a sight you want to see, but it's also no reason to think that something sinister is happening in our Missouri lakes.