Growth‐rate and smolting‐rate of progeny of male Atlantic salmon parr, Salmo salar L.

In experiments conducted in two successive years, the progeny of male Atlantic salmon parr (Salmo salar L.) were found to grow in length at the same rate as the progeny of sea‐run males. The proportions of these populations which smolted at one year old did not differ in the first experiment, but were significantly higher among progeny of parr (33%) than among progeny of sea run‐adults (21%) in the second year. Survivals throughout the experiments were high, at 89 and 91% respectively in the two years. A possible inhibitory relationship between smolting and sexual reproduction in the same year is discussed.