Round goby (Neogobius melanostomus) is a highly invasive bottom-dwelling fish from the freshwater region of Europe's Black and Caspian Seas. They have voracious appetites which allows them to displace and outcompete native species.
Description
Round gobies are brownish-gray in color with dark brown or black splotches. During spawning and nest guarding season(April-September), males have black bodies with yellowish spots and median fins with a yellowish-white outer edge. Gobies and related species are most easily identified by their characteristic puffy cheeks, like those of a chipmunk. Their eyes are large and raised like those of a frog. When fully grown their size ranges from 4-10 inches in length. Round gobies can be distinguished from other species by the presence of a prominent black spot at the base of their first dorsal fins. They have a single, fused pelvic fin. The pelvic fin is the most important characteristic to distinguish them from sculpins, a native lookalike which has two separate pelvic fins.
Distribution and Habitat
Round goby are typically found in freshwater but can tolerate mildly saline waters. They are now present in all the Great Lakes. Their populations have spread by swimming from the Great Lakes through the Erie Canal and Mohawk River to the Hudson River. They are not yet found in Lake Champlain. They also continue to spread to inland lakes.
Impacts
- Round goby negatively impact the environment, fish and wildlife populations, and the economy.
- Because they are aggressive, reproduce quickly, and have voracious appetites, they outcompete and reduce native fish populations, which in turn negatively impacts the fishing and tourism industries.
- They are a link between the invasive, disease-carrying mussels that they feed on and the native wildlife that feed on the goby, significantly increasing the mercury content of sportsfish, as well as the instances of botulism outbreaks among native fish and diving birds.
- They act as a vector for viral hemorrhagic septicemia (VHS), a serious, fatal fish disease affecting many native species.
Management
The best method for managing round goby is preventing its spread from one body of water to the next. Other management options can be successful depending on the size and location of the infestation. Options include physical activities like using traps, dams, canal locks, electrical barriers, and earthen barriers to deter movement, as well as application of the chemical rotenone.
Management methods should be evaluated on a case by case basis for each infestation. For help with selecting the best management for your situation, contact your local Partnership for Regional Invasive Species Management (PRISM).
Spread
Round goby was introduced into the Great Lakes through ballast water on ships from the Black Sea in the early 1990s. They can spread by being transported and dumped from bait buckets and water-containing compartments of boats as well as by swimming through both natural and manmade waterbodies such as rivers and canals.
How You Can Help
- Clean, drain, and dry your watercraft and equipment thoroughly before visiting other waterbodies.
- Inspect and remove debris and mud from boats, trailers, and equipment.
- Dispose of all debris and bait in trash cans or at disposal stations.
- Drain all water-holding compartments including live wells, bait wells, and bilge areas. If possible, visit a decontamination station and disinfect compartments with hot water (140°F) for at least 30 seconds.
- Dry boats, trailers, and all equipment before use in another water body. A minimum of 5-7 days of drying time in dry, warm conditions is recommended.
- Do not dump aquarium contents in any waterbodies, drainage ditches, or sewers.
- Use certified bait that is non-invasive and disease free.
- Learn how to identify round goby and report any encounters.
- If you think you have found round goby:
- DO NOT RELEASE IT
- Take several photos of it from different angles, including the underside, and freeze it, then throw it in the trash after ID has been confirmed.
- Email the photos, noting where it was caught (coordinates preferred), to [email protected], OR
- Submit a report through iMapInvasives, OR
- Contact your local Partnership for Regional Invasive Species Management (PRISM).
- DO NOT RELEASE IT
