Articles : Outbreak

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Outbreak:
Disease In Our Already Threatened Fisheries
By: Steven James Rusteberg

By now we have all seen the movie. A deadly virus has threatened to wipe out an entire population of people. It infects everyone in its path, sparing no one who has come in contact with it. The epidemic threatens the species as we know it. CAN THIS HAPPEN IN THE MUSKIE WORLD? The answer: It has and continues to!
Many fishermen are uninformed and/or under informed about two diseases that infect the Muskie population. Both are contagious, and continue to spread. This article is not written with intention to panic the entire Muskie fishing community, but in fact, to wake people up into the realization that our valued Muskie is threatened as a species.
All information acquired for this article was sparked by my interest in the fact that many of our researchers and biologists had no idea that two different Muskie communicable diseases do exist. Many that I talked with were confusing one with the other, or simply were not aware that more than one was in existence. Many of the symptoms of the diseases are similar. Thus, the confusion continued.
All the information in this article was provided through professional works, done by members of the scientific community. I don’t pretend to know all the answers, nor do I credit myself with a biology or zoology degree. My information was obtained by several phone calls to Larry Ramsell (Muskie historian, tracking study assistant, Musky Magazine Research Editor), Dick Day (Aquatic Biologist Ohio Division of Wildlife), and a man named Bob Marshall (Ohio Muskie Lake Correspondent). All forwarded me scientific information on the diseases, their outbreaks, and information relating to diagnosis.
The two diseases that I am referring to in this article are “Red Spot,” and Lymphosarcoma. Due to the fact that these infectious diseases are so much alike that even some biologists confuse the two, I would like to separate them in the article to reduce the amount of confusion. The first part of this article will discuss “Red Spot.” The second will continue with identification of Lymphosarcoma. Remember that I am not a scientist, and I interpreting scientific information for the lay man, thus any misinterpretation or misstatements are on my part, not my sources or the scientists.

“Red Spot Disease”
This disease has been the cause of several recent population die offs. You may remember that in the late seventies to early eighties a “Muskie epidemic” was beginning to emerge. Pymatuning Reservoir, on the Ohio/Pennsylvania boarder, was in trouble. A massive die off was in its early stages of epidemic. Literally hundreds of Muskie were found floating dead on the surface by the mid eighties. The scientific community was stunned! One of Muskie fishing greatest honey holes was dying. To date Pymatuning Reservoir has never recovered to its once plentiful population of Muskie. The disease was later coined to be “Red Spot.”
Occurrence
Red Spot Disease can occur in any body of water, due to its bacteria relation. All lakes, streams, and rivers contain Aeromonas (genera) bacteria. According to scientists, this bacteria are most common in water, that of which has heavy organic content. This fact did not alarm me because all bodies of water need organic matter to naturally clean itself (No big deal there). The next fact did alarm me. The way these bacteria multiply are the special situations that threaten our Muskie populations. High water temperature, low oxygen levels, crowded fish populations, and stress all will increase the possibility of mass reproduction of these bacteria, thus the disease is more likely to multiply and spread. Scientists also say that the accumulation of waste products can also be a factor. Peak susceptibility is in the month of June, July, and August.
Transmission
How does one Muskie infected with the Aeromonas bacteria give it to another? First it is important to point out that just because the Muskie carries the bacteria doesn’t mean he has the disease of “Red Spot.” I found this easier to understand when it was compared to a disease of my (human) generation. Just because a person is infected with the HIV virus, doesn’t mean the person has AIDS. He or she is a carrier. The same is true with the Aeromonas bacteria in an individual Muskie. That Muskie is a carrier not necessarily infected with “Red Spot Disease.” Also the presence of the bacteria doses not necessarily mean that mortality will occur.
The disease is passed from one Muskie to another, most commonly, during the reproductive period. In years that have moderately hot springs, the disease is passed on even more rapidly during the spawning period. Due to the increasingly warming temperatures in the shallows and unusual unseasonably hot weather the bacteria reproduces at an alarming rate. Also, because of the the loss of the spawning grounds, Muskie are forced to spawn closer together. They tend to cluster, increasing the stress of the spawn, thus, the massive spread of the disease. A whole spawning population of Muskie may be infected.

“RED SPOT”
IDENTIFICATION AND CHARACTERISTICS
1. Red circular skin irritation (bleeds to the touch)
2. “Popeye” fluid causing the eye to look as if it were swollen or popping out
3. Fins and joints inflamed
4. A deep healed round crater (a fish in the 1% that may have survived)

PREVENTION
One of the most common lake to lake spread of “Red Spot” is transmission of infected fish to new bodies of water. Hatcheries must be very careful that infected fish are not transplanted to other water. No transmissions through genus, or through genetics have proven to be a known cause of the spread. Therefore, hatcheries can milk and egg fish without a concern, but must make sure that hatchery condition such as low oxygen, high water temps, and contact with infected adults does not occur.
Scientists have experimented with several different drugs that have proved to be effective in fighting the disease. The problem is cost effectiveness of these drugs. Every infected fish must be injected. Time and money would be excessive. The solution seems futile.

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The second threat: LYMPHOSARCOMA
If you’re an avid Muskie hunter like me, many of you may have already heard of this disease. Larry Ramsell was talking of this disease back ten years ago when he did his study (Muskie sabbatical) with Dr. Le beau. Larry first remembers hearing of this disease at the Muskie Inc. Symposium in the seventies. Lymphosarcoma is different in many ways from “Red Spot.” Lymphosarcoma is a malignant blood cancer. It too is highly contagious, and fatal in most Muskie infected.
OCCURRENCE
Lymphosarcoma has been around since the ice ages, and according to scientists, played an important role in natural selection. This is not to down play the importance in the knowledge of this disease. To this author’s knowledge, Lymphosarcoma has not yet threatened to wipe an entire Muskie population (such as “Red Spot” has and continues to do). Do not take Lymphosarcoma lightly, however, it is still a communicable disease in the Muskie population.

TRANSMISSION
Lymphosarcoma is transmitted only by skin contact. According to scientific study, it affects the back third part of the fish most often. This disease is transmitted during the spawn through open wounds, sores, and scrapes. Do not confuse this with “Red Spot” characteristics that may or may not involve contact (fish to fish). High water temperatures help the enzyme in the blood reproduce quickly, thus, causing a tumor and eventually death. This disease seems to be more stress related in this authors study of these two diseases. This is a Muskie cancer of sorts. The back posterior of the fish is often infected causing the kidney to fail, and leukemia to kill. Sexually mature fish seemed to be the most infected, probably due to the spawning process.

LYMPHOSARCOMA
IDENTIFICATION AND CHARACTERISTICS

1. Red BUMP or swelling on back one third of fish
2. An open nodular tumor on fish
3. Tail and/or fins split
4. A divot in fishes posterior (1% that may have survived)

PREVENTION
Lymphosarcoma has been around for hundreds of years. This disease seems to be nothing new in a Muskie’s realm. Again transportation of brood stock, hatchery conditions, and the young must all be closely monitored by conservationists and biologists. Once a body of water is infected, there is no stopping the disease from spreading. Nature must take its course.

THE ANGLERS ANGLE:
After doing extensive research in order to write this article, there were many ethical questions in my mind. Do I release an infected fish (It will surely spread the disease to others)? I am not a scientist. I cannot kill a fish based on my belief it is infected. How can I be positive? Based on my catch and release only way of thinking I would have trouble killing any fish infected or not. I am forced to release a “suspected” fish until I am yet, further educated about the two diseases. This is a question that may weigh heavy on all of our shoulders if these two diseases continue to spread. Unless you are positive that a fish is infected (beyond a reasonable doubt), this is by no means a reason to terminate a fishes life. Criticism will likely follow the angler using this excuse to keep any fish (trophy or not).
The best thing an angler can due, is to report suspected infected fish to the Department of Natural Resources of that particular state or Provence. If the fish is kept, maybe even offer to donate the corps to the division of resources. If nothing else just to identify the disease, and report an illness. A detailed photo of an infected area on a released fish can also be helpful. For now this will be the solution to my ethical choice.

CONCLUSION
These diseases continue to affect the Muskie’s world. Education of the scientists, biologists, and anglers is the immediate solution to this outbreak. Clear Fork Reservoir in Ohio, and Chautauqua Lake in New York are currently the most threatened by disease. I hope this article has opened some thought to the possibility that Muskie fishing could be threatened in our immediate future on infected lakes. I also hope my interpretation of the data is accurate, and an understandable interpretation. I welcome input, and more education and interpretation into this article.