To understand and to predict demographic rates of a population, one needs to understand how individual life-histories, their evolution, and assumptions made about those can influence population dynamics. Here, I present a simulation model that incorporates ecological and evolutionary dynamics of fish life-histories. The model is parameterized for Atlantic cod and applied to two case studies: 1) To investigate the role of the survival cost of reproduction on the demography and adaptation of life-histories, and 2) To investigate the effects of fisheries-induced evolution on extinction risk and recovery ability of a population. The simulations suggest that the survival cost of reproduction is a substantial component of natural selection, and omitting it leads to underestimation of the age and size at maturity and overestimation of spawning stock biomass. In contrast, the effects of fisheries-induced evolution on population growth rate remain minor, suggesting that fisheries-induced evolution might not affect the extinction risk and recovery rate of an exploited population, as previously hypothesized.
Anna Kuparinen
Ecological Genetics Research Unit
Department of Biosciences, University of Helsinki