THE INFLUENCE OF REARING CONDITIONS ON THE SIBLING ODOR PREFERENCE OF JUVENILE ARCTIC CHARR, SALVELINUS-ALPINUS L

Individuals of two full sibling families of Arctic charr were reared from the egg stage, either together with siblings, or in isolation. When tested in a fluviarium, the fish reared with siblings preferred water scented by unknown siblings to water scented by non-siblings. The fish reared in isolation were indifferent when given a choice between water scented by siblings and water scented by non-siblings but preferred water scented by siblings to unscented tap water. When 15 months old, previously isolated individuals were reared with siblings for 50-62 days. These fish were, however, still indifferent when given a choice between water scented by sibling and water scented by non-siblings. These results strongly suggest that social experience sometime during the first 15 months is essential for the development of sibling preference in Arctic charr. © 1992 The Association for the Study of Animal Behaviour.