Heat and drought are blamed for killing 20,000 fish on a Missouri lake.
But softening that blow was the fact that nearly all of the fish that died were invasive Asian carp, the Missouri Department of Conservation told KQTV.
Heat and drought cause low dissolved oxygen levels, which caused fish to die at Lake Contrary, a St. Joseph, Mo., lake about an hour north of Kansas City.
“The lake’s been experiencing warmer waters and temperatures and depressed oxygen for the last several weeks,” MDC Northwest Regional Fisheries supervisor Scott Ryan told the station.
Warm, fertile water sometimes promotes excessive growth of tiny aquatic plants known as algae. That's fine as long as the sun shines and the tiny plants are using sunlight to put oxygen in the water. But cloudy weather turns algae from oxygen producers into oxygen consumers, so a couple of overcast days can have disastrous results for fish.