Demographic Consequences of Precocious Maturation of Atlantic Salmon (<i>Salmo salar</i>)

Abstract

Detailed records of outgoing smolts of Atlantic salmon (Salmo salar) and estimates of the parr population that produced them were used to study the demographic conequences of male precocious sexual maturation in southwest Newfoundland. Approximately 80% of males matured precociously in the stream. Annual survival probability of a male that reproduces precociously is reduced by a median 44%. Precocious maturation delays smolting; the probability of smolting in the second year for a male precocious parr is approximately 13% of that of a female. The economic loss due to precocious maturation is large; 60% of the adult male salmon production is lost due to precocious maturation.