EFFECT OF PARENTAL NUMBERS ON CHROMOSOME PATTERNS POUND IN ARTIFICIALLY PRODUCED ATLANTIC SALMON STOCKS

The number of wild Atlantic salmon Salmo salar that return to Spanish rivers has steadily decreased because of environmental degradation and overfishing. To alleviate this decline, juvenile salmon obtained from adults returning to Asturian rivers are used in a supplementation pro gram. Gametes from no more than 35 adults are used to create groups of juveniles that are released back into the wild. We examined the effec t of parental numbers on the chromosomal patterns found in juveniles p roduced by this protocol. When less than 20 parental fish were used, t he chromosomal patterns found in their offspring were significantly di fferent (P < 0.001) from those found in naturally produced fish. Conse quently, in supplementation endeavors, at least 20 parents should be u sed to create groups of juveniles.