| Impact ID | 8370 |
| Impact Type | Predation/Herbivory |
| Study Type | Observational |
| Study Location | Field |
| Impact Description | The fishhook waterflea's (Cercopagis pengoi) establishment in Lake Ontario in 1998 corresponded with the lowest alewife populations in twenty years. |
| Reference | 13069 |
| Cost | |
| Location | Hamlin Beach State Park, Lake Ontario, New York, USA |