| Impact ID | 8583 |
| Impact Type | Competition |
| Study Type | Observational |
| Study Location | Field |
| Impact Description | Throughout much of its distribution in North America, Schmidtea polychroa feeds primarily on oligochaetes. However, in Toronto Harbour, Ontario, Schmidtea polychroa and Dugesia tigrina are found to coexist; the latter is found at lower densities at each locality, suggesting potential intra-specific competition between the triclads. |
| Reference | 16804 |
| Cost | |
| Location | Lake Ontario, Toronto Harbour, Canada |