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Fact Sheet
Scientific Name (Echinogammarus ischnus)
Classification and Permitting Level 1 - Prohibited Aquatic Nuisance Species
Species Description Scud are small, invasive crustaceans called amphipods that can get up to about 0.4 inches in length. Scud can move across solid surfaces and are active swimmers, even against currents.
Preferred Habitat They are typically found in shallow water with hard substrates.
Reason for ANS Designation This species can displace native species of amphipods, which are an important food source for some invertebrates and fish. While overall impacts are relatively minor, there are no known control methods for this species.
Place of Origin Scud are native to Eurasia around the Black and Caspian seas. They were first reported in the United States in the mid 1990s. They are primarily moved with water movements.
Stopping the Spread When taking equipment out of a lake or stream, remove all plants and mud and drain all water prior to leaving. Allow the equipment to dry completely, rinse with 140°F water for 10 seconds of contact, or disinfect using an approved method such as a .02% bleach solution for 10 minutes of contact time or freezing for 72 hours.
Additional Information USGS Fact Sheet