On the Age, Growth, Migration, Reproductive Potential and Feeding Habits of the Arctic Char (Salvelinus alpinus) of Frobisher Bay, Baffin Island

Abstract

The Arctic char (Salvelinus alpinus Linn.) was studied, in the summers of 1948, 1950 and 1951, about the mouth of the Sylvia Grinnell River, Frobisher Bay, Baffin Island.Otoliths are shown to be reliable age indicators and are used for age determination. Because of deficiencies in the sampling of the fish a calculated growth curve has been constructed. The calculated growth rate is obtained by showing the relationship between otolith width and fish length and expressing it in the equation: log (fish length) = −1.503 + 1.982 log (otolith width). The relationship between otolith ring diameter and fish age is demonstrated, and from these two relationships the lengths of fish at earlier ages are calculated.The char grow very slowly, and reach an age of more than 24 winters. They migrate to the sea in late June and return to fresh water from late July until September. The first movements to the sea probably occur during the fifth, sixth and seventh summers. Sexual maturity in the females is reached at a length of about 45 cm., and at an age of approximately 12 winters. Egg counts of maturing fish averaged 3,589. Only about 33 per cent of the females over 45 cm. were maturing. At least 30 food species were found in the stomachs.Additional growth, fecundity and food studies were made on small samples from George River, Herschel Island and Adlorilik.