Although contemporary trends indicative of evolutionary change have been detected in the life-history traits of exploited populations, it is not known to what extent fishing influences the evolution of alternative life-history  tactics in migratory species such as salmonids. Here, we build a model to predict the evolution of anadromy and  residency in an exploited population of brook charr, "Salvelinus fontinalis". Our model allows for both phenotypic  plasticity and genetic change in the age and size at migration  by including migration reaction norms. Using this  migration reaction norm, resulting in a decrease in average  probabilities of migration with increasing harvest rate. Moreover, we show that differences in natural mortalities in freshwater greatly influence the magnitude and rate of  evolutionary change. The fishing-induced changes in migration predicted by our model alter population abundances  and reproductive output and should be accounted for in the sustainable management of salmonids.