Round Goby
Neogobius melanostomus

• Length: 4 to 10 inches (250 mm)
• Coloring: grey with blotches of black and brown over their bodies, dorsal fin may be tinged with green, the front dorsal fin has a distinctive large black spot
• Common Names: Round goby, goby
• Found in Lakes: Michigan, Huron, Erie, and Superior

Although gobies belong to a family of fish with a worldwide distribution in both salt and fresh water, they had not been found in the Great Lakes prior to 1990. The round goby first turned up in Lake Superior's Duluth/Superior harbor area in 1995. Presumably, the fish arrived in ballast water discharged by trans-oceanic ships.

 

It can be difficult to distinguish between round gobies and sculpins, but the goby's fused pelvic fin is the best way to tell them apart.

round goby	sculpin

 

Also native to the Black and Caspian seas region, its cousin, the tubenose goby, appeared for the first time in the St. Clair River in 1990; however, this species--which is endangered in its native habitat--has remained uncommon in the Great Lakes.

Gobies also are capable of rapid population growth. They spawn repeatedly during the summer months, and each time, a female can produce up to 5,000 eggs. The males die after spawning.

In Europe, the diet of round gobies consists primarily of bivalves (clams and mussels) and large invertebrates, but they also eat fish eggs, small fish and insect larvae. In the United States, studies have revealed that the diet of round gobies includes insect larvae and zebra mussels.

Local laws vary regarding the possession of round gobies. Take a look at your state or province regulations, and contact your local authorities if you need more information.