In the alpine environment fish have adapted to the torrential regime of the watercourses. In the Park territory, fish include two important salmonids: the Brown Trout (Salmo trutta), which lives in all the aquatic habitats of the Park, from springs to brooks and small lateral streams, to the large valley watercourses and artificial basins, and the Marble Trout (Salmo trutta marmoratus). Usually, the Brown Trout is the dominating species in minor watercourses, while its presence is reduced in larger streams, where the Marble Trout dominates, like the stream Cordevole and the lower stretch of the stream Mis. In the Park, the Bullhead (Cottus gobio) is also present: it is an indigenous species very sensitive to environmental changes and pollution, and is nowadays in slow but continuous recovery. More discontinuous is the presence of other species, like the Brook Trout, the Minnow, the Rainbow Trout, the Bleak, and the Chub.