The Diana Bend Conservation Area is seeing a fish die-off this fall after a summer of the Missouri River flooding. The Missouri River has expanded into its flood plains throughout the state. Now as the river recedes this fall, fish are left behind cut off from the river.
“It serves as pretty great habitat for spawning and everything for fish reproduction,” Rebecca O’Hearn, a resource scientist at the Missouri Department of Conservation, said. “However whenever the flood waters recede and everything goes back into the river, some of the fish don’t go along with the water back into the river and remain up in the flood plain.”
“They’re just kind of stranded there in the flood plain with very little water that just continues to evaporate and warm up,” O’Hearn says. “They start to consume all of the oxygen in the water that’s left in the flood plain and eventually they will suffocate.”
The majority of the fish in the Diana Bend area are Asian Carp, an invasive species of fish. These typically non-native fish reproduce rapidly, pushing out other species. This can lead to a less diverse population in the river. These invasive species are the most likely to be caught in flood plains, as they are the most eager to find ideal places to spawn.
There are no other reported incidents of fish die-offs in the state at this time, but this occurrence at the Diana Bend Conservation Area is a natural part of the rise and fall of the river, O’Hearn says.