Most gobies are marine although some species enter freshwater and a few permanently reside in freshwater. The distinguishing characteristic of gobies is that their pelvic fins are fused into a sucking disc, allowing them to hold position in turbulent or high-velocity water, such as surge zones or torrential streams. They also lack a lateral line. Recently two species of Eurasian gobies were introduced into the Great Lakes and at least one of these species, the round goby, has gained access to New York waters. It is abundant in both Lakes Erie and Ontario and has become increasingly more common in the state's streams and lakes during the last decade. It is a bottom-dwelling fish and is successful in a variety of habitats.
Round Goby lives in streams, large lakes and canals with rocky bottoms and it has been in NY since only the late 1990s. It will likely be moving farther east in the Erie Canal and Mohawk River in the years ahead.