- Round goby are small (usually less than 7 in. [17.8 cm]), mottled gray and brown fish with a prominent black spot at the rear of the first dorsal fin. All gobies have their pectoral fins fused to a single suction-cup-like disc. They have frog-like, raised eyes
- Habitat and Habits
- Native to the Ponto-Caspian region of Eastern Europe. Round goby occupy the nearshore, preferring rock, cobble or riprap. Lacking a swim bladder, they are bottom-dwelling, perching on rocks and other surfaces with fused pelvic fins. They tolerate a wide range of conditions, including low oxygen and high pollution.
- Ecological Threat
- Round goby were introduced to the Great Lakes via ballast water, first discovered in 1990 near Detroit and reported in all five Great Lakes by 1995. Round goby also can spawn multiple times per season. Round goby are aggressive predators of fish eggs, such as those of native smallmouth bass, and contribute to the decline of many valuable sport fish populations. They are aggressive competitors with small, native fish and other bottom-dwellers. Round goby are highly territorial for food, shelter and optimal spawning sites. Often, anglers are the first to discover round goby because these aggressive fish are commonly caught by hook and line and are a serious nuisance to anglers using live bait. They can be spread by bait bucket transfers and further ballast releases. Do not use gobies as bait!
- Fact Sheet - Ontarios Invading Species Awareness Program