Round Goby (Apollonia melanostomus)
The round goby (Apollonia melanostomus) poses a serious threat to North American aquatic ecosystems, with potential impacts on sport and commercial fishing. Since its discovery in the St. Clair River in 1990, this bottom-dwelling fish has rapidly spread to many areas of the Great Lakes. Once established, populations typically increase quickly. The round goby can displace native fish, eat their eggs and young, take over optimal habitat, spawn multiple times a season, and survive in poor quality water -- giving them a competitive advantage.
Anglers, commercial fishermen, and fishery professionals should know how to identify the round goby. Often, anglers are the first to discover round gobies because these aggressive fish are commonly caught by hook and line. Your help to report new sightings and to prevent their spread is vital.
Identify Round Goby
- No other native fish in the Great Lakes has the single pelvic fin
- Young are solid slate gray
- Usually 3-6 inches (7-15 cm) long, may be up to 10 inches (25 cm)
What You Can Do
- Learn to identify the ruffe.
- Inspect and remove aquatic plants, animals, and mud from boat, motor, and trailer.
- Drain water from boat, livewell, and bilge before leaving any water access.
- Dispose of unwanted live bait and worms in the trash.
- Never dump live fish from one body of water into another.
- If you catch a round goby outside the St. Louis River, kill it, freeze it, and call the Minnesota Sea Grant Program in Duluth, (218) 726-8712, or the Minnesota Department of Natural Resources in St. Paul, 1-888-MINNDNR or (651) 259-5100, or a local DNR fishery office.
Do not throw it back alive!
Know the Rules!
Round goby specimens are needed to confirm sightings, but many Great Lakes jurisdictions have different rules regarding possession and transport. Always contact your local resource management agency for instructions. Never transport a live round goby.