The Individual Based Salmon Ecogenetic Model IBSEM has previously been used to elucidate population-level phenotypic and demographic consequences of gene-flow from domesticated Atlantic salmon in wild populations in both Canada and Norway .
Here, we present new and novel features of the model including the ability to output individual-fish phenotype (as opposed to population averages only) and individual-fish admixture . The latter feature is computed using an ancestry-tag within the model itself (thus reflecting individuals % of farm ancestry ) and admixture as estimated by sets of molecular genetic markers under differing degrees of selection.
The model was re-tuned to mimic the Atlantic salmon population in the river Etne in Norway where extensive empirical data are gathered on the effects of domestication-introgression. The model was run on a time-scale (25-50 years introgression 25-50 years “recovery”) and with levels of gene-flow (via 0-25% escapees on the spawning grounds) that reproduces the introgression scenario observed in the river Etne.
The results of this work are very interesting and have significant implications for setting management limits for biological tolerance levels. N ot least, this work also has important implications on how we interpret admixture estimates from empirical studies in the wild using molecular genetic markers - especially during the “recovery” phase.
All will be revealed in August ☺