| Specimen ID | 116416 |
| Group | Mollusks-Bivalves |
| Genus | Dreissena |
| Species | polymorpha |
| Common Name | zebra mussel |
| State | IL |
| County | Cook |
| Locality | Lake Michigan, 12th Street Beach, Chicago,IL |
| Mapping Accuracy | Accurate |
| HUC8 Name | Lake Michigan |
| HUC8 Number | 04190000 |
| HUC10 Name | Lake Michigan |
| HUC10 Number | 0419000002 |
| HUC12 Name | Lake Michigan |
| HUC12 Number | 041900000200 |
| Map | |
| Collection Day | 20 |
| Collection Month | 9 |
| Collection Year | 1991 |
| Year Accuracy | Actual |
| Potential Pathway | shipping |
| Status | established |
| Comments | Extremely good visibility. Higher pop. density on rock than on steel. Light surface density, high density in crannies. Site subject to continual wave action. |
| Record Type | Literature |
| Verifier | The Aquasphere Project, Dolton, IL |
| Freshwater/Marine | Freshwater |
| Number Collected | 38 |
| Size | 11.7 - 19.6 mm , Avg.= 16.0 mm |
