Pond Boss
Posted By: heybud Dying Bass Story - 07/24/06 08:40 PM
LA CROSSE, Wis. - 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.

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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.

___

On the Net:

Wisconsin Department of Natural Resources: http://dnr.wi.gov/
Posted By: Theo Gallus Re: Dying Bass Story - 07/24/06 08:59 PM
Sometimes I think Bass Tournaments are as good for bass as football is for pigs.
Posted By: burgermeister Re: Dying Bass Story - 07/24/06 09:23 PM
Amen, brother!
Posted By: Cecil Baird1 Re: Dying Bass Story - 07/24/06 10:09 PM
I used to live on a lake where there were bass tournaments. You could always count on seeing some dead bass a couple days after the tournament. Many anglers think if the fish swims away right after release it's fine. I know better.
Posted By: Dave Davidson1 Re: Dying Bass Story - 07/24/06 11:26 PM
Yeah, but did you notice that some were held for up to 5 days?
Posted By: bobad Re: Dying Bass Story - 07/25/06 12:30 PM
LMB virus? Isn't it best that susceptible fish are removed from the lake anyway?
Posted By: Dave Willis Re: Dying Bass Story - 07/25/06 01:20 PM
Here are a couple of the latest on LMB virus. It seems like ages since I've actually posted something like this before Ewest could get to it! \:\)

Journal of Aquatic Animal Health 17:304–314, 2005

Effects of Factors Related to Water Quality and Population Density on the Sensitivity of Juvenile Largemouth Bass to Mortality Induced by Viral Infection

KATE R. INENDINO AND EMILY C. GRANT
Department of Natural Resources and Environmental Sciences,
University of Illinois, Champaign, Illinois 61820, USA
DAVID P. PHILIPP
Center for Aquatic Ecology, Illinois Natural History Survey,
and Program in Ecology and Evolutionary Biology, University of Illinois,
Champaign, Illinois 61820, USA
TONY L. GOLDBERG*
Department of Veterinary Pathobiology, College of Veterinary Medicine,
and Program in Ecology and Evolutionary Biology, University of Illinois,
Champaign, Illinois 61820, USA

Abstract.—Environmental stressors can predispose fish to mortality from infectious disease. This
study examined the effects of two factors, water quality and physical crowding, on the responses
of fish to viral infection. Juvenile largemouth bass Micropterus salmoides were experimentally
inoculated with largemouth bass virus (LMBV), an emerging pathogen in the family Iridoviridae.
In separate experiments, fish were exposed to various concentrations of nitrate (0, 40, 200, and 400 mg/L) and were housed at either high or low population densities. Survival time, viral load (quantity of virus in tissues), and body condition were measured as outcomes. Nitrate, as well as other water quality parameters such as ammonia, nitrite, and pH, affected mortality rates and viral loads in complex ways. Paradoxically, increased nitrate concentrations were associated with reduced mortality rates in juveniles exposed to LMBV. In general, rapid fluctuations in the concentrations of dissolved toxins had greater impact on sensitivity to viral infection than did persistently high levels of these toxins. Fish housed at high density experienced increased mortality rates,
elevated viral loads, and reduced body condition compared with fish held at low density. These
results demonstrate that both physiochemical and social environmental stressors can affect the
survival and condition of largemouth bass infected with LMBV.

Journal of Aquatic Animal Health 17:315–322, 2005

Effects of Practices Related to Catch-and-Release Angling on Mortality and Viral Transmission in Juvenile Largemouth Bass Infected with Largemouth Bass Virus

EMILY C. GRANT AND KATE R. INENDINO
Department of Natural Resources and Environmental Sciences, University of Illinois, Champaign, Illinois 61820, USA
WILLIAM J. LOVE
Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Illinois, Urbana, Illinois 61802, USA
DAVID P. PHILIPP
Center for Aquatic Ecology, Illinois Natural History Survey,
and Program in Ecology and Evolutionary Biology,
University of Illinois, Champaign, Illinois 61820, USA
TONY L. GOLDBERG*
Department of Veterinary Pathobiology, College of Veterinary Medicine,
and Program in Ecology and Evolutionary Biology,
University of Illinois, Urbana, Illinois 61802, USA

Abstract.—Largemouth bass virus (LMBV; family Iridoviridae) has recently emerged as a causative
agent in fish kills of largemouth bass Micropterus salmoides. Little is known about how the virus is transmitted or what factors predispose fish to mortality subsequent to infection. Concern has nevertheless arisen that activities related to recreational angling may affect transmission dynamics and may alter the susceptibility of infected fish to clinical disease. This study examined the separate effects of two angling-related factors on the susceptibility of juvenile largemouth bass
to mortality from LMBV infection and on the transmission of LMBV from infected to uninfected
fish. The first factor was hook-and-line angling. Infected fish that underwent a simulated angling treatment did not experience higher mortality or have higher viral loads in their tissues than those that were not angled. The second factor was direct contact between infected and uninfected fish, as would occur in live wells and holding tanks. The LMBV was transmitted from infected to uninfected fish through water, even when direct contact was prevented. Transmission of LMBV between infected and uninfected fish separated by a fenestrated barrier was nearly as efficient as LMBV transmission between infected and uninfected fish that were allowed direct contact. These
results imply that angling itself may have only minimal effects on the survival of largemouth bass infected with LMBV but that angling-related practices that place infected and uninfected fish
together in a limited water volume may facilitate viral transmission. Partitioning or cooling of live wells and holding tanks, as well as limiting their use, could reduce LMBV-associated mortality and viral transmission.
Posted By: ewest Re: Dying Bass Story - 07/25/06 02:32 PM
Thanks Dave I am always glad to share the load ( I can't come close to doing half of what needs to be done) but am glad to help where I can. \:\) The AFS Black Bass Symp. has several articles on this very topic (Bass Tour. morts) but they don't deal with LMBV. Uhgg this event sounds like a "Perfect Storm" situation. \:\(
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