LAKE WINNEBAGO, WI (WTAQ-WLUK) – The DNR is keeping close tabs on Lake Winnebago after round goby, an invasive species, were found in the lake. And they’re asking the public for help too as it tries to monitor the situation and keep the waterway healthy.
First detected in the Lake Winnebago system, specifically Little Lake Butte des Morts, in 2015, the presence of the round goby led to the closure of the Menasha Lock ten years ago. The idea was, by closing the lock it, would keep the round goby from spreading further into the system.
An invasive species, the round goby and has the potential to impact Lake Winnebago’s sport fish through competition for prey and by eating their eggs, from spreading further into the system.
A decade later, however, it happened and the round goby have found their way into Lake Winnebago.
“In June of this summer we had our first angler report, through our online reporting tool from this very pier here. This is the Bowen Street Fishing Pier in Oshkosh – which was our first verified goby, said Patrick Siwula, a DNR aquatic invasive species biologist.
At that time, the DNR activated its response which included additional monitoring and community outreach – as it was unable to detect the round goby near the pier.
But then, about two weeks ago, when another angler caught more round gobies out, of the same area of Lake Winnebago, the DNR fished another 10 out of the lake too.
“It is concerning,” said DNR fisheries biologist, Angelo Cozzola. He added, “It’s something we don’t want to see, we don’t want have invasive species in our system, having these unknown consequences that no one can really predict.”
The DNR says while the population of round goby has exploded in Little Lake Butte des Morts and they’ve become a nuisance to anglers who catch the bait stealers regularly, the most recent survey of the waterway, determined the effects of the round goby are undetectable.
Cozzola said, “We did not see any significant impacts to any of the main fish we look at, pan-fish species, game fish species. In that situation, in the assessments we have seen there haven’t been much.”
With the long-term effects of the round goby still unknown, the DNR continues to monitor the situation in Lake Winnebago. Once introduced into a waterway the round goby can’t be eradicated, so plans on how to handle what has been discovered in Lake Winnebago is still being studied and discussed.
According to Siwula, “If we could do a rotenone treatment in an enclosed area, if we’re only finding gobies in that area, that could be a possible mitigation to try and get them out of the system, but at the same time we don’t have a good handle on if they maybe present elsewhere yet.”
That’s why the DNR is asking anglers to help and to report any round goby sightings in Lake Winnebago, either by bringing them to local DNR service centers or using the online reporting tool.
Even with the round goby present in Lake Winnebago, the DNR says it has no plans to re-open the Menasha Lock or Neenah-Menasha dam, because it’s believed they are still the best barriers to continue to prevent the spread.
