The bloody red shrimp prefers habitats associated with hard structures or rocky bottoms and actively avoids direct sunlight. It has a unique swarming behavior unlikely to be confused with anything else in the Great Lakes. During daylight hours, it may be observed forming reddish swarms in the shadows of piers, boats, or breakwalls. Swarms disperse at night, but in clear calm waters, the bloody red shrimp may be detected at night by shining a bright light on the water—the shrimp will rapidly swim away from the light. It is unknown at this point whether zebra and quagga mussel beds in the Great Lakes will be suitable habitat for the shrimp. The species avoids soft bottoms and vegetation. In its native range, across Europe and in the Baltic Sea, the bloody red shrimp is found in water depths to 50 meters (166 feet). It seems to prefer slow moving waters, but has been found along rocky, wave-exposed shorelines. The shrimp is also reported to spend daylight hours hiding in rocky crevasses and boulder cavities, but has also been observed swarming in shadowed areas near the surface by day.
What you can do to prevent the spread of this invasive species
- Learn to identify bloody red shrimp
- Inspect and remove aquatic plants and animals from boat, motor, and trailer
- Drain lake or river water from livewell and bilge before leaving access
- Dispose of unwanted live bait in the trash
- Never dump live fish from one body of water into another
- Report sightings of bloody red shrimp to Tip of the Mitt Watershed Council at
(231) 347-1181 or by e-mail at firstname.lastname@example.org or to NOAA Great Lakes Environmental Research Laboratory Hemimysis Survey and Monitoring Network at www.glerl.noaa.gov/hemimysis .
While long-term impacts on the Great Lakes are not yet known, the bloody red shrimp is considered a high risk invader to inland lakes in the Great Lakes region.