Elton Creek is a Class 1 trout stream between Antigo and White Lake in Langlade County.
This week the Wisconsin DNR announced it found a parasite called Myxobolus cerebralis in wild trout in that stream. It’s not been found in wild fish in the state previously.
The DNR started testing for it after the parasite was found in a nearby fish farm.
“The Department of Agriculture, Trade and Consumer Protection notified the Department of a positive test for myxobolus during a routine fish health certificate testing of rainbow trout on a private fish farm. That led the department to work with DATCP staff and implement a wild fish testing program as a precaution following this notification,” said DNR Fish Culture Section Leader David Giehtbrock.
In some cases, the parasite can lead to whirling disease. Giehtbrock says the disease does what it says, makes the fish whirl or spin in circles.
“Other things that happen is it causes spinal or skeletal deformities. It also causes a black tail,” said Giehtbrock. “These are all things that are, you know, observable by someone. Then, it also causes fish to just drop out of the population, they die. We noticed population changes based on the fact that the fish are no longer there.”
There are other things that can cause whirling disease in fish.
While the DNR has found a parasite that can cause whirling disease in Elton Creek, they did not find signs of the illness among trout in the stream. The DNR is implementing a surveillance program to determine if any additional trout populations have been affected.
The parasite does not post a health risk to humans. It’s not been known to affect animals like otter or mink that may eat an infected fish.
Giehtbrock says it also seems to be limited to trout and salmon, with rainbow and brook trout being the most susceptible.
“We have areas in the country that haven't really noticed, or seen clinical signs, or signs that there's a serious problem with whirling disease present in the environment. Then in the West, a lot of fisheries have been seriously affected by the parasite in the past,” said Giehtbrock. “It kind of remains to be seen how bad this could be or what will happen exactly to Wisconsin trout populations now that we know it's out on the environment.”
Now that it’s in a wild fish population, there’s no getting it out, but there are things anglers can do to help slow its spread.
That includes thoroughly cleaning all gear after fishing, including waders, nets, and float tubes as well as boats and trailers. Make sure you’re not transferring water, mud, or fish between water bodies.
Anglers are encouraged to report any signs of the whirling disease to the DNR.
