Page 7 - Round Goby Flipbook

Zebra mussels are a major component of the round

gobies’ diet in their native range of central Eurasia with

some reports finding that a single goby can eat 78 zebra mussels per day. However, the use of

biocontrol techniques (using one species to reduce/eradicate another species) can often times

result in unintended consequences, and it is generally not a good idea to use this technique.

Also, there are often both positive and negative impacts associated with invasive species.

While gobies would most likely eat zebra mussels, it is not known if their impact would result in

a large decline in zebra mussels or if a decline would

even be detectable (a mature female zebra mussel may

release up to one million eggs per year). In the Great

Lakes, round gobies can potentially spread deadly

botulism through the food chain, which is acquired when

gobies eat infected zebra mussels and then ducks eat

the gobies. The gobies will also aggressively defend

their spawning habitat that native fish also need to

reproduce. As a result, a lot of small native fish may

not be able to find a place to reproduce if gobies

were to establish in large numbers. Shoreline

fishing may also be negatively impacted by Round gobies are known

round gobies. Anglers in Chicago and to be present in all the Great Lakes,

Milwaukee are catching many round as well as in attached tributaries up until

gobies from shore as this fish the first impassable dam. They have also been
reproduces quickly, is very detected in portions of the Illinois River and where
aggressive, and attacks lures. the Illinois and Mississippi rivers converge. However,
The DNR wouldn’t consider according to the U.S. Geological Survey, round gobies
have not been found in the Mississippi River. The Prairie
stocking round gobies in Lake du Sac dam along the Wisconsin River is one physical
obstacle that the round goby (or other invasive fish
Winnebago (or any other WI

waterbody) due to the immense

complexity and potentially species) is unable to pass, and serves as a barrier to

negative impacts that can occur. upstream movement. There are eight identified locations

It is easy to add an animal to an where there are potential connections between the

aquatic ecosystem but nearly Great Lakes basin and the Mississippi River basin.

impossible to remove it. The U.S. Army Corps of Engineers assessed these

locations and it was concluded that there is

a low risk of aquatic invasive species

movement between the two

basins.

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