A deadly fungus is spreading in a river in Montana which is nullifying the immune systems of the local trout and make them susceptible to other forms of illnesses as well. The experts are concerned as this could disrupt the population of the other fishes over the years to come, since the fungus is disrupting spawning season.
At this time of October each year, the brown trout in Hole River located near melrose in southwest montana can be seen digging into the riverbed with the their tails and making spawning nests called redds. However, the intense labor of making redds and the tremendous sparing matches which break out between males at the right so as to fertilize a bunch of eggs has been known to cause problems in the thin layer of slime which helps the fish to be protected from illnesses.
“The fungus is taking advantage of these fish when their ability to fight an infection like this is at its lowest point,” Fisheries Manager Travis Horton of the Montana Fish, Wildlife and Parks (FWP) department explained in a statement.
But he’s swift to add that even though this may call for attention, it is not a cause of concern just yet. “That’s because the fungus is naturally occurring in these spots, and has been frequently observed affecting parts of the river with denser populations of trout. You can even think of the fungus as a kind of population cap,” adds Horton
“The important thing to remember is this is a system of stress,” he added. “The fungus is natural and although the incidence is locally high, it isn’t a cause for alarm.”
However, the local biologists are having an eye on the fungus which is a fibrous grey freshwater mold that seems to be more prevalent during this time of the year. But Horton says that Big Hole is having a ‘perfect storm’ of growing conditions. Chris Clancy who is a Bitterroot based fisheries biologist assured the local fisherman that the fungus does not seem to be infecting any more trout than the usual number even though its population is growing.
“Occasionally, a fisherman will see a fish not acting well in some quiet water and notice that it’s covered in a growth that looks like cotton,” Clancy told the Ravalli Republic.
But, he adds, it’s nothing to lose sleep over.