Storm causes rare fish kills due to hail

News from the region
Kansas City
Published Date

Kansas City Mo - Extreme hail from recent thunderstorms in the Kansas City area killed fish and Canada geese at a Northland lake, a conservation biologist says.

Suddenly chilled water temperatures caused the fish kill and falling hailstones probably killed the geese.

“I’ve never seen this happen before, and I’ve been at this for 24 years,” said Jake Allman, a fisheries biologist for the Missouri Department of Conservation (MDC).

The hail fell when microburst thunderstorms rolled across the metro area on Sept. 18, downing power lines and trees. Hail stones more than five inches in diameter were reported in some places, according to the National Weather Service in Pleasant Hill. The hail accumulated deep enough in places to prompt snow plows to clear streets, a meteorologist said.

Hail fell so thick in one Kansas City, North, neighborhood that it caused a sudden water temperature change that killed catfish, bass, bluegill and carp in a park lake at the city’s Lakewood Greenway, Allman said. The hail may have also caused problems for fish elsewhere.

A man from the Smithville area called Allman on Tuesday (Sept. 21) to inquire what might have killed frogs and his oriental Koi fish, which he kept in a backyard pond with about a five-foot depth. That area was struck by one of the storms, which also twisted a boat dock at Smithville Lake into wreckage. Allman suspects hail might have caused a sudden chill in the water that can kill fish, and the frogs might have been killed by falling hail.

Then on Thursday (Sept. 23), Allman investigated a fish kill in a popular fishing pond at the Lakewood Greenway off North Norton Ave., south of Northeast Vivion Road. He found several fish floating dead in the pond.

An area resident told Allman he had seen hail up to six inches deep in yards, and he had seen dead Canada geese at the pond after the storm. The geese, removed by a park crew before Allman arrived, may have been killed by the hail.

Fish cannot survive sudden changes in water temperature, he said, nor can they survive low oxygen levels in water. The hail falling into the pond and chilled runoff either dropped the water temperature enough to trigger the fish kill. Another possibility is that the hail and cold storm water runoff caused the pond water to suddenly “turn over,” bringing water with little or no oxygen to the pond’s upper reaches and killing fish.

The Lakewood Greenway pond is stocked with channel catfish regularly as part of the MDC's urban fishing program. Allman said more channel catfish would be stocked in the pond soon to replace those killed by the hail storm.

No other fish kills had been reported to conservation offices as of late Friday.