La reproduction des poissons de nos rivières

This video film gets a general view of the main aspects of the reproduction biology of freshwater fishes living in Belgian Rivers. Attention is drawn on to three species : the grayling Thymallus thymallus ; the barbel Barbus barbus and the bream Abramis brama. Other fish species are also brielly considered : roach, carp and perch. The spawning sites are presented, followed by a detailed description of the sexual behaviour. As a general rule, each male grayling spawns with one female. In some cases, sneaking males can take part in the spawning act too. As far as barbels and breams are concerned, groups of males spawn with one female in the first case whereas reproduction resorts to the arena system in the latter. The interest of conservation and restoration of the spawning sites are presented through two exemples : management of a salmonid River and use of artificial spawning grounds.