To have a large number of observations for comparison, the data from both 2008 and 2009 at the first assignment level were compiled for comparison with the modelled distribution for 1 year. In addition, our results indicate that interannual variations in the direction (and strength) of the surface currents alter post-smolt migration routes. a rheotactic behavioural response, in accord with the results from recaptured tagged fish and the published literature (Shelton et al., 1997; Booker et al., 2008). This helps them move from the coastal areas near their spawning grounds to rich feeding areas, and … The following experiments were conducted: (a) post-smolt migration from west of Ireland in 2008; (b) post-smolt migration from west of Ireland in 2002; (c) post-smolt migration from west of Ireland in 2002 including temperature/salinity influenced swimming behaviour; and (d) post-smolt migration from southwest Norway in 2008. It was assumed that hatchery-reared fish would undertake the same migration and would have the same swimming speed as wild fish. They spend their first winter at sea south of Greenland and their second growing season at sea off the coast of West Greenland and sometimes East Greenland. The potential for salmon to adapt to changes depends on the magnitude, rate, and duration of the change (Ottersen et al., 2004). An exponential line was fitted to these data (L = 7.34 e0.0059t, r2 = 0.969, p < 0.001; Figure 3). Some Atlantic salmon spend a single winter at sea before returning to spawn in freshwater. This value is close to the constant value (20 cm s−1) used by Booker et al. The swimming component has two elements: direction and speed. Atlantic salmon returns: 2020 turned out to be a remarkably good year in most Atlantic salmon rivers, but not all.The Penobscot in Maine had 1,601 return. comm.). Origin and migration of wild and escaped farmed Atlantic salmon, Oceanic migration in homing Atlantic salmon, The marine phase of the Atlantic salmon (, Dispersal of the radionuclide caesium-137 (, Spatial and temporal distribution of post-smolts of Atlantic salmon (, Migration and distribution of Atlantic salmon post-smolts in the North Sea and North-East Atlantic. For example, U.S. salmon leave Maine rivers in the spring and reach the seas off Newfoundland and Labrador, Canada, by mid-summer. Atlantic salmon are migratory species. Ocean current fields were simulated with the three-dimensional numerical Regional Ocean Modelling System (ROMS; www.myroms.org; Haidvogel et al., 2008). Individual migration routes for six tagged Atlantic salmon (tag IDs are given above panels). Unlike Pacific salmon, Atlantic salmon can spawn multiple times in their life. Atlantic salmon (Figure 1) has an elongate body that is somewhat compressed laterally; the greatest depth is at the dorsal fin origin and it becomes deeper with age. Once they have reached their breeding grounds, the females dig depressions, known as 'redds', in the gravel; the eggs and sperm are released simultaneously into the water. Additionally, the particle-tracking model has a built-in behavioural module that was modified for individual post-smolt growth and active swimming behaviour. Some have been known to eat salmon eggs. The simulated distributions of the southern and northern stock groups also indicate that the different stocks overlap both spatially and temporally, although they enter the sea at different locations and times of the year. 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