The first sighting of a round goby in the United States was in
the St. Clair River in 1990. They most likely arrived through the ballast water of
freighter vessels. The round goby found its way into Lake Erie and Lake Michigan by
1993. In only a year, these populations became established. By 1995, round gobies were
found in Lake Superior and other parts of Lake Erie and Lake Michigan. Due to the
disjunctive populations found in the early years, it is likely that these populations
represented different introductions. One population in Lake Michigan was found 12
miles east of the Grand Calumet River. This river is connected to the Mississippi River
meaning that there is the potential for the gobies to spread into America’s largest
watershed.
Round gobies likely hitchhiked in the ballast water from ships
coming from the Black and Caspian Seas. Once in the Great Lakes, they were able to
establish a dense population very rapidly. Just as with their initial introduction pathway,
round gobies could be picked up in ballast water from the Great Lakes and taken to other
locations in the United States. Most at risk is the Mississippi River due to the Chicago
Sanitary and Ship Canal that links the Great Lakes vessels with the Illinois River
(Mississippi River drainage).
Round gobies have already spread to one Indiana inland lake, Wolf Lake. There is a
waterway connection between Lake Michigan and Wolf Lake that allowed the gobies to
swim into the inland lake. The round goby can also swim into the Mississippi River
drainage through the Chicago Sanitary and Ship Canal. An electric dispersal barrier has
been installed in the canal to prevent fish migration between the two watersheds. At this
time, no gobies have made their way into the Mississippi basin.
Anglers and aquarium hobbyists are also a possible mode of dispersing this species to
other bodies of water. However, it is illegal to possess a live round goby in Indiana. If a
goby is caught, it must be killed immediately and not returned alive.
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