MADISON, Wis. – The Wisconsin Natural Resources Board (NRB) recently approved an emergency Wisconsin Department of Natural Resources (DNR) rule regarding the capture and take of the invasive round goby in the Winnebago System.

A round goby from Lake Winnebago was first reported by an angler and confirmed by Oshkosh DNR staff on June 2, 2025, and additional gobies have been caught and reported by anglers since this initial capture. 

The new emergency rule will allow anglers in the Winnebago System waters to keep in their possession any harvested round gobies provided that the fish are eviscerated, decapitated or had their gills removed. Since a round goby population has not been established in these waters, angler harvest and reporting of all gobies taken will serve as a critical tool for tracking the presence of round gobies in the Winnebago System. The rule will be in effect June 19 – Nov. 16, 2026.

The DNR asks anglers to be on the lookout for any round gobies in the Winnebago System and to report their catch. There are also several annual monitoring surveys on Lake Winnebago, as well as additional projects that allow for further detection of round gobies in the Winnebago System.

Round gobies are an aggressive invasive fish that reproduces quickly and can survive in poor water quality, leading to the displacement of native fish populations.

They have been present in the Great Lakes since the early 1990s, including associated tributaries (such as the Lower Fox River) up to the first impassable dam or barrier.

Round gobies were discovered in Little Lake Butte des Morts along the Lower Fox River above the impassible barrier at Rapide Croche in 2015. In response, the Fox River Navigational System Authority (FRNSA) closed the Menash Lock located between Lake Winnebago and Little Lake Butted des Morts to prevent the round goby from entering Lake Winnebago and the upper watershed.

Targeted monitoring and public outreach/reporting programs are ongoing, with no confirmed reports of round gobies upstream of the Menasha and Neenah dams until the angler report on June 2, 2025. The DNR continues to consider the Menasha dam, Neenah dam and the closed Menasha lock essential barriers to preventing the spread of round goby to Lake Winnebago.

What To Do If You Catch A Round Goby On The Winnebago System:

Anglers that capture a suspected round goby in Winnebago System waters should decapitate or eviscerate the fish or remove the gills and report it to the DNR. The best way to report the goby is to use the DNR’s Online Goby Reporting Tool, which includes an illustration of a round goby and will prompt the angler to include a photo to facilitate ID verification. DNR staff will then contact the angler.

Alternatively, anglers may also bring suspected goby specimens to the DNR’s Oshkosh office to facilitate ID verification by freezing or putting the deceased specimen on ice in a plastic bag. The office is open 8:30 a.m. – 4 p.m., Monday through Friday

Any round gobies captured downstream of the Neenah or Menasha dams or in Little Lake Butte des Morts do not need to be reported, as it is not a part of the Winnebago System and these areas are known to have a verified and established population of round goby.  Gobies captured in Green Bay or Lake Michigan also do not need to be reported.

Help Prevent The Spread

Prevention remains the best way to help protect Wisconsin’s waters as round gobies are nearly impossible to eradicate once they have been established. However, steps can be taken to limit the spread. Under chapter NR 40, Wis. Admin. Code, round goby are a restricted species in Wisconsin, meaning they cannot be transported (unless they have been decapitated, eviscerated or had their gills removed), transferred or introduced. A deceased goby can be legally transported to a DNR office for identification.

Anglers are reminded to never use round gobies as bait, release fish from one lake into another or throw unwanted bait into the water.