Migration, growth and survival of wild and hatchery‐reared anadromous Arctic charr (Salvelinus alpinus) in Finnmark, Northern Norway

Abstract

Two groups of anadromous Arctic charr (Salvelinus alpinus) (size 200–350 mm) reared in heated water (6–12° C) under simulated natural photoperiod were individually tagged and released in spring 1988. The fish were released at two sites, in the estuary of the River Halselva and in the fjord, 2 km from the river mouth. Growth, timing of migration and survival of these hatchery‐reared fish was compared to that of wild anadromous charr of the same size over a 4‐year period. The hatchery‐reared charr had poorer growth than the wild fish during their first year in sea water. They also resided longer in the sea and had a slightly lower survival than wild fish. During the second year, hatchery‐reared charr displayed good growth, and after the third sea‐season the fish were ready for slaughter at a size of approximately 800g. The results suggest that the successful development of Arctic charr ranching will be dependent upon production and release strategies that lead to improved migratory and feeding behaviour of the fish during their first season at sea.