Last weekend, boaters and beachgoers stumbled upon a grisly scene at Lake McConaughy. The carcasses of around 1,000 fish had washed up onto the reservoir’s shores.
Around 99% of the dead fish were white bass. More than that, they were all adult white bass, mostly between 15.5 and 17 inches.
As to what killed them, biologists haven’t got a clue.
“There’s nothing conclusive at all,” Fisheries biologist Darrol Eichner of the Nebraska Game and Parks Commission said.
The fish carcasses were found mostly on the west side of the lake. Eichner said the areas around the Cedar View and Lakeview campsites were especially hard-hit.
Already, Eichner and his team have conducted studies to rule out potential causes. Pollution was ruled out as a cause.
“There are more sensitive species ... that would succumb to a pollutant before white bass,” he said.
No evidence of point source pollution coming from a pipe or other container have been found.
Tests to measure algae content and oxygen levels show that these, too, are not the cause of the event. Both were recorded at normal levels. Eichner said the die-off might be related to the weather or the wind, but more evidence is needed to know for sure.
“There are periodic mass die-offs in Lake McConaughy,” he said.
Many of them are similarly unexplainable.
“The difference is ... social media. News of this one spread like a virus.”
Eichner said there was no reason for the public to be concerned. The lake is still safe for swimmers, anglers and anyone else who isn’t a white bass. If other species aren’t being impacted, humans shouldn’t be either.
Biologists are still trying to get to the bottom of the mystery, but to do so they need to catch fish first.
“Labs require tissue to be from living fish to check for diseases and viruses,” Eichner said.
Some white bass were collected on Wednesday and sent to the University of Nebraska-Kearney laboratory to check for parasites.
So far, none have been found.
“These were healthy fish,” Eichner said.