Here's why:
* Habitat: Otters typically prefer clean, freshwater rivers and lakes with abundant fish and vegetation. The Tiber River, flowing through Rome, is heavily urbanized and polluted, making it unsuitable for otters.
* Species: European otters, the species most likely to be found in Europe, have historically been absent from areas with high human population density. While they are making a comeback in some areas, the Tiber River is not a likely habitat.
There have been no confirmed sightings of otters in the Tiber River.