Chub

Names in dialect: squal, cavazin.

Chub are slender in shape, with a grey body and fins and white belly. They have a large head, silvery eyes and a wide mouth, with the upper jaw slightly longer than the lower one. Their fairly large scales have dark edges, which give them a criss-cross pattern; 41 – 48 scales can be counted along the lateral line. Chub in lakes can exceed 50 cm in length and 3 kg in body weight.
Chub are gregarious and are often found together with common barbel in watercourses in valley bottoms, downstream from reaches inhabited by Salmonids. Chubs tend to be greedy, feeding on water invertebrates, small fish, algae, winged insects, and the seeds and fruits of plants; amateur fishermen sometimes catch them with seasonal fruit, such as blackberries or cherries.
They spawn from May to July, moving in small schools to gravel substrates in shallow waters: each female lays 20 – 30,000 eggs. The fry hatch after a few weeks. They are known to form hybrids with dace and bleak.
Chub are one of the species most resistant to the degradation of water environments and indeed it is not rare to see shoals of chub around discharges from purification plants. The construction of hydroelectric barriers has encouraged this species to breed in areas where salmonids are found, both in the upper basins and in the courses downstream where the little water left in summer heats up and pollutants no longer find their primary means of dilution. Chub are not a good food fish and contain lots of bones.