The contribution of supplementary sea water to the mineral balance of Atlantic salmon alevins

Ole J. Torrissen and Karl D. Shearer

Fisk. Dir. Skr. Ser. Ernæring Vol. 5 No 2, 1992


The contributions of Ca, K, Mn, Na, P, and Zn were monitored in eggs and larva of Atlantic salmon (Salmo salar) incubated in buffered freshwater and buffered freshwater to which 2% seawater was added. Ca concentrations were significantly higher in the larva reared in the seawater supplemented water, but did not differ in the incubating eggs. The levels of the other elements did not differ in the eggs or larvae. Mortalities in the larva reared in freshwater increased after hatching but remained low in the seawater-added group. The results suggest that the low Ca concentration present in the acid waters of western Norway may be responsible for increased mortality and retarded development in Atlantic salmon fry.