Bass virus continues to spread

[Hamilton Reef]

FOR IMMEDIATE RELEASE, 24 MAY 04
CONTACTS: Gary Whelan, 517-373-6948, or
James Dexter, 517-373-3375

Bass virus continues to spread in Michigan waters

State fisheries officials today announced Largemouth Bass Virus continues to spread in southern Michigan lakes, and called upon anglers to help contain the disease and protect fish populations.

Largemouth Bass Virus is among more than 100 naturally-occurring viruses that affect fish. It is not known to infect humans, and infected fish are considered safe to eat. However, it is recommended that all fish should be thoroughly cooked as a precaution.

When LMBV was detected in the fall of 2000 in Lake George, on the Michigan-Indiana border, it was the first time the disease had ever been found in Michigan and was the furthest north LMBV had ever been found in the United States. The disease was first discovered in 1995, in South Carolina’s Santee-Cooper Reservoir, following a die-off of largemouth bass. Since then, it has been detected in wild fish from 17 states including Indiana, Illinois and
Michigan.

The Department of Natural Resources surveyed lakes in Southern Michigan for LMBV in 2002 and continued in 2003. Based on these and earlier data, the virus has been confirmed in 15 of 30 lakes examined. A list of surveyed lakes is available on the DNR web site, www.michigan.gov/dnr.

Michigan DNR Fisheries Division and Michigan State University researchers continue to investigate LMBV and will monitor lakes throughout Michigan this summer.

Michigan DNR Fish Production Manager Gary Whelan said LMBV appears to infect other fish species, including smallmouth bass, bluegill, and crappies, but has caused mortality only to largemouth bass. The disease typically kills large adult fish and die-offs impact approximately 10 percent of these fish in a given lake.

There are few outward signs that a fish has the virus. Mortality occurs when fish are most stressed. Potential stressors include very hot weather, high angling pressure, and possibly aquatic weed or other treatments during very hot periods. Any measures that can be taken to minimize stress on these fish will reduce the impact of the disease and mortality.

“The DNR cannot eradicate this virus or treat affected wild fish populations,” Whelan said. “However, as we continue investigating this disease, we appreciate receiving reports of unusual fish mortalities.”

The DNR called on anglers who target largemouth bass to voluntarily help reduce angling stress on bass populations during warm weather, and reminded anglers and boaters to take the following steps to help prevent the spread of the virus:

* Clean boats, trailers, other equipment thoroughly between fishing trips to keep from transporting LMBV, as well as other undesirable pathogens and organisms, from one water body to another with special care to clean fishing equipment when you are done fishing known locations of the virus.

* Do not move fish or fish parts from one body of water to another, and do not release live bait into any water body.

* Handle bass as gently as possible if you intend to release them and release them as quickly as possible.

* Refrain from hauling the fish for long periods in live wells if you intend to release them.

* Minimize targeting of largemouth bass during the period from mid-July to mid-August, especially during exceptionally hot weather conditions.

* Report dead or dying adult largemouth bass fish to Michigan Department of Natural Resources Fisheries Division offices.

* Volunteer to help agencies collect bass for LMBV monitoring.

* Educate other anglers about LMBV.

The Michigan DNR will continue to communicate new information learned about the disease in Michigan. For more information, visit: http://espn.go.com/outdoors/bassmaster/index.html.

[ESOX]

* Do not move fish or fish parts from one body of water to another, and do not release live bait into any water body.

* Handle bass as gently as possible if you intend to release them and release them as quickly as possible.

* Refrain from hauling the fish for long periods in live wells if you intend to release them.

* Minimize targeting of largemouth bass during the period from mid-July to mid-August, especially during exceptionally hot weather conditions.








Considering that tournaments do a lot of what the DNR says not to do in regards to this, perhaps they should suspend issuing permits for tournaments during July and August.

[djkimmel]

This whole issue came up when LMBV was first identified in Lake George. The MDNR was preparing to issue a press release saying just that until the BASS federation, national BASS and some very respected national bass fisheries biologists came out publicly and stated that the MDNR had absolutely no need to react that harshly; had no scientific basis for the action; and appeared (once again) to have some kind of issue with bass tournaments and tournament anglers that most other states don't have.

The MDNR backed down quickly and released a more realistic and accurate statement similar to this one that at least somewhat more closely matched what is known nationally about LMBV -

instead of putting a target on the back of anyone who happens to own a bass boat and fished anywhere in Michigan in July and August for any fish.

First of all, many of our waters do not reach the temperatures that are shown to increase the likelihood that the LMBV kills bass (85 F and above through most of the water).

Most infected bass never show any signs of illness and don't die.

LMBV does not make smallmouth bass sick. We can fish for smallmouth bass all we want without causing their demise due to LARGEMOUTH Bass Virus. Many tournaments are held concentrating on smallmouths since they have increased in many lakes and are especially prevelant in the Great Lakes.

We've only found LMBV in 15 lakes - out of 11,000 so it is ridiculous to stop tournaments in the name of not stressing largemouth bass in the 10,985 lakes that aren't known to have the virus, especially considering how few LMBV die-offs we've had in Michigan since it was first found.

Some of the lakes they surveyed did not have the virus and there have not been any significant die-offs in most of the lakes.

Tournaments release their bass back into the same body of water they are caught in in most cases, or at least lakes that are connected by navigable water - the recommendations are for not moving fish from one unconnected lake to another. AND we don't use live bait, so we won't be releasing any minnows into the water.

Tournaments rarely bring in a significant percentage of the adult bass population in their livewells from most lakes. Many tournaments have voluntarily chosen to lower team bass limits to below the state allowed creel limit too, further lowering the percentage of bass kept in livewells.

You will notice in earlier infected lakes that the virus level usually tapers off after the initial infection.

In all cases nationally, only one major die-off occured, when one did occur, on a lake - not all lakes suffer a die-off and you will also see that the percentage of bass that die-off is not a huge percentage of the adult population.

Most lakes have recovered quickly because of this, and because they suffer no further die-offs due to the virus.

The most important thing is to just try to keep the virus out of lakes it isn't in. With our highly mobile trailered boating public, that will be difficult, but can be minimized if all boaters (not just tournament boaters) follow the recommendations.

[ESOX]

We've only found LMBV in 15 lakes - out of 11,000 so


What I meant to say was they they shouldn allow tourneys on lakes with LMBV during July and August. Are there any tourneys scheduled in that time frame on infected lakes?


The most important thing is to just try to keep the virus out of lakes it isn't in. With our highly mobile trailered boating public, that will be difficult, but can be minimized if all boaters (not just tournament boaters) follow the recommendations.


Very true. Unfortunately, the incessant spread of the zebra mussel to inland lakes shows that there will always be people who don't folloe the reccomendations posted by the DNR.

Could the bounceback after a dieoff somehow be attributed to some fish being immune to LMBV, or developing antibodies to LMBV?

[Skeeter]

Just wanted to pass this on to you Bass fisherman that a product called Bio-zyme will kill the bacteria in your live well. This product was formulated by a bass fisherman a few years ago. Biozyme is a liquid, live bacteria live-well cleaner and maintenance product. Spray it in the live-well and rinse it out. Leaves a clean smell and kills bacteria. It is a unique blend of 7 live enzymes that will kill the bacteria in your wells. It also contains a deodorant that eliminates odors instantly leaving your live well with a clean smell. :fish: Skeeter

It is listed on my web page which is listed below. I am not a bass fisherman but it sure does the trick on the walleye smell. I sell a lot of it.

[djkimmel]

What I meant to say was they they shouldn allow tourneys on lakes with LMBV during July and August. Are there any tourneys scheduled in that time frame on infected lakes?

Some of those lakes are very popular. I'm sure there are tournaments. After a die off occurs, there's not much reason to not have tournaments anymore. I don't know of any states that have limited tournaments to try to prevent LMBV die offs. It's possible it has been done on some lakes. I just haven't heard that.


Could the bounceback after a dieoff somehow be attributed to some fish being immune to LMBV, or developing antibodies to LMBV?

What I have read is that researchers are not sure why some fish get sick and die and many don't. Anymore than they know why it kills some largemouth bass, but infects other types of fish without harming them. So far, one consistent factor has been that lakes have one die off and no more. They aren't really sure why that happens.

It's supposed that largemouths develop some kind of tolerance to the virus as a whole. I would think it is just as likely that only a small number of largemouths are susceptible enough to die. The rest aren't susceptible enough to die and their offspring are the same.

I think an interesting question to answer would be how did it get into Lake George from more southern lakes - they originally didn't think it would be able to infect northern lake largemouths? Hard to believe someone brought bass up from a much more southern lake and let them go. Hard to believe a virus stayed alive somehow in a boat traveling that far. No one seems to have any real good ideas other than that.

[deputy865]

just my opinion i jut hope they keep tourney i really was going to do alot this year mostly was going to find out about them from all you people here at MS.
if you dont mind me asking what does the virus look like or what do you look for.


any one notice black dots all over bluegills? there is a ton of them on some of the gills i caught can anyone help give me a better understanding on what theses "black dots" are? PM me with any info

[djkimmel]

if you dont mind me asking what does the virus look like or what do you look for.

The only way to be sure a fish has LMBV is to test it in a laboratory.

any one notice black dots all over bluegills? there is a ton of them on some of the gills i caught can anyone help give me a better understanding on what theses "black dots" are? PM me with any info

There are parasites that can cause what you describe on fish. Probably what it is. Won't hurt you if you cook the fish well.

[Skeeter]

Check out this URL for more info.

http://espn.go.com/outdoors/bassmaster/index.html