Fish kills are mostly acts of nature, says Missouri Conservation fisheries specialist

Missourinet – There have been a few notable fish kills in Missouri this year. But they’re not unusual, according to Andrew Branson with the state Department of Conservation. He said that many fish kills are caused by nature or weather conditions:

“Thermal stress during breeding as water is warming up and fish are getting active, they’re starting to spawn coming out of winter. That can be a stressful time for fish and that can also kill some fish.

“As heavy rains are falling and that rain’s hitting the ground and it’s flowing across the ground into the body of water, into the lake or pond, as that rainwater travels across the ground it’s actually losing oxygen to the ground. So, by the time that water comes dumping into the lake or pond, quite often that water is low on oxygen.”

Branson says the main cause of fish kills is oxygen deprivation in the water, but Algae blooms – rapid growth of bacteria in water — can also cause fish kills.

One recent fishkill that was caused by pollution happened last month at a creek in the southwest Missouri’s Lamar, when wastewater flowed out of a manhole cover into the creek.