Is “Largemouth Bass Virus” Heading North?

Originally seen in Fish’n Canada’s Week in Review

A little-known fish disease might be in need of a name change after 14 Wisconsin smallmouth were confirmed to have “Largemouth Bass Virus”.

Largemouth Bass Virus, as the name would suggest, is the only known virus that is known to be lethal and, up until now, was thought to be exclusive to the species. This all changed when tests were carried out on 14 smallmouth bass caught in Green Bay, Wisconsin – confirming that the virus has now made its way into local smallmouth populations.

As seen in the photo above, the disease is recognizable by the large red sores it causes on the fish, often displaying a white patch of dead flesh in the centre. In addition to being hard to look at, the disease is also known to cause abnormal swimming, weakness, and swimbladder over-inflation – a combination that has led to large kills in Largemouth populations.

Fortunately, the disease has not proved fatal in the smallmouth that have been sampled but local conservation authorities will be keeping a close eye on the fish caught in this area for signs of further spread. In the meantime, authorities are asking anglers to strictly adhere to live well and fish transport regulations to avoid the disease spreading to other waterways.

Here in Canada, no cases of the disease have been reported, however, Ang and Pete did catch some Largemouth last weekend with some interesting markings.

“We thought it was due to Muskie or Pike or some other nasty predator,” said Pete, “but the wounds seem too round.”

Let us know what you think in the comments below!


This excerpt was taken from Fish’n Canada’s Week in Review, our weekly recap of all things relevant to the Canadian outdoorsman. For more stories like this, check out the full article below and tune back in every Friday to catch up on everything you missed!