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BiologyGregarious. Adults occur in fairly shallow water with fast current, often beside the swirls created by piles of bridges or rocks (Ref. 30578). They inhabit moderate to fast-flowing large to medium sized rivers with rock or gravel bottom. Larvae occur below surface and feeding larvae inhabit along shores. Early juveniles live on the bottom in very shallow shoreline habitats. When growing, they move from the shore for faster-flowing waters. Juveniles overwinter in backwaters or in cavities along shores. During winter, adults form dense swarms in lower parts of rivers. Larvae and early juveniles prey on small invertebrates while larger juveniles and adults feed on benthic diatoms and detritus. Adults migrate upstream some tens of km to spawning sites which are often located in tributaries. Spawning occurs in fast flowing water on shallow gravel beds (Ref. 556, 59043). Its flesh is good but bony (Ref. 30578). Locally threatened by damming, destruction of spawning sites and pollution. In drainages where they are introduced, they outcompete and eliminate Parachondrostoma toxostoma in Rhône and Protochondrostoma genei in Soca (Ref. 59043).