The default life history schema for Salmo salar L. (myopically known in English as Atlantic salmon) is anadromous, with spawning occurring in freshwater rivers. The juveniles grow for one to eight years in their natal surroundings (Metcalfe and Thorpe 1990; Klemetsen et al. 2003), then physiologically transform from parr into smolt and emigrate to the sea, where they to grow for one to fi ve more years before returning to their spawning sites to spawn, sometimes repeatedly (Thorstad et al. 2011). However, there are aberrations from this life cycle, referred to as sedentary, non-anadromous or landlocked, meaning effectively that such populations are isolated from the sea and never contact marine ecosystems; this means that they do not experience saline waters, a marine diet or marine parasites. The word anadromous itself refers only to migration, but has for a long time carried a marine/freshwater connotation.