APPLETON, Wis. (AP) -- Boaters traveling from Green Bay to Lake Winnebago are facing obstacles because of an invasive fish called the round goby.
Wisconsin Public Radio reports that most of the 16 locks that run between De Pere and Appleton on the Fox River are open, but two of them will remain closed this season.
The Rapide Croche lock hasn't reopened since it was closed to block a different invasive species found in 1988.
The Wisconsin Department of Natural Resources ordered the Menasha lock closed in 2015, when the goby was found in Little Lake Buttes Des Morts. The lake feeds into the Fox River flowing into Lake Michigan.
The fish originates in Eurasia and is thought to have come to the United States in the ballast water of large ships as early as 1990.