Response of the Atlantic Salmon (Salmo salar L.) Population of the Keret River to the Invasion of Parasite Gyrodactylus salaris Malmberg

摘要

Since 1992, most juvenile Atlantic saknon Salmo salar from the Keret River (White Sea basin) have been infected with the dangerous parasite G. salaris almost every year. Decreasing the population size, G. salaris affected the salmongene pool. Wild juveniles from the Keret, in contrast to juveniles from other rivers, were found to have a higher fluctuating asymmetry of scull bones in comparison with cultivated juveniles. Hybrids between the Atlantic salmon and brown trout (S. trutta) were found in theriver. On the basis of analysis of the patterns of allozyme marker distribution, one may conclude that there were rapids where only one pair of Atlantic salmon spawned in some years. At the same time, we have found an increase in frequency of one haplotype of mitochondrial DNA. The response likely has an adaptive character