Hundreds of dead bass have been collected from La Crosse-area river waters, days after a major fishing tournament was held in the region, a state official said.
Nearly all of the 582 bass were marked with a clipped tail fin, evidence they were caught and released during a bass-fishing tournament from July 12-15, said David Hobbs of the state Department of Natural Resources.
This is the second year that higher-than-normal fish deaths were reported in the area following the Wal-Mart FLW Stren Series Bass Fishing Tournament, which attracted 400 anglers.
Last year, most of the dead fish tested positive for largemouth bass virus, which can cause death when the fish is stressed.
The majority of the fish Hobbs collected this year were largemouth, and he said the stress of being caught, held in a livewell and released might be a factor in their deaths.
As part of an ongoing study, the DNR clipped the tail fins of the more than 2,000 bass caught and released during the four-day tournament. The research, conducted by the DNR and fishery biology researchers at the University of Wisconsin-Stevens Point, focuses on mortality rates in bass-fishing tournaments.
The study is in response to a 2003 Wisconsin law calling for an investigation of the economic, sociological and biological impacts of catch-and-release programs in bass tournaments. Results are expected in early August.
Veteran tournament angler Ed Stellner, 53, of Onalaska, said anglers are concerned but they question the DNR study.
“If we are killing the fish, we definitely want to know why,” he said. “However, I also should point out that there’s a bass-fishing tournament in La Crosse every weekend, and when’s the last time you saw this many dead? After last year’s tournament (which was the first year of the study).”
Perhaps the way the DNR conducted the study was a factor, Stellner said.
The agency put about 100 fish a day in 8-by-8-foot holding pens on the Black River. An equal number of tournament-caught fish and fish culled from the wild using electroshocking were kept for a side-by-side comparison.
The pens didn’t have proper current flow, which could have raised water temperatures and limited oxygen levels, Stellner said. Also, the fish were held for up to five days, another possible source of stress, he said.
Hobbs confirmed Stellner’s account of the holding pens but said the electroshocked fish weren’t among those he collected because they did not have a clipped fin.
Hobbs collected the fish from Pettibone Beach to Airport Beach.
Tournament official Dave Washburn of FLW Outdoors, based in Benton, Ky., said Monday that “clearly we’re all concerned” about the fish deaths.
But “we have a lot to learn about how to conduct the study,” he said.