![]() Protection of Atlantic salmonįind out about the Atlantic salmon as a protected species of fish. It’s one of the reasons why Scottish populations are so important from a biodiversity perspective. ![]() Salmon may, of course, enter Scotland’s rivers at any time of the year – which is not the case for Atlantic salmon observed elsewhere. ![]() Salmon that return to Scottish rivers from January to June are called ‘spring salmon’. They’re larger than grilse as they’ve spent more time feeding in marine environments (usually off Greenland). ‘Multi-sea-winter salmon’ – or simply ‘salmon’ – are those fish that remain at sea for two to three years before returning to Scotland. ‘Grilse’ are those fish that spend only one year at sea (usually around the Faroe Islands and southern Norwegian Sea) before coming back to Scottish rivers. These fish remain in the ocean from just over a year to three or four years. Some of these fish feed in the Norwegian Sea and the waters off southwest Greenland. Some research has shown that post-smolts move in schools when heading to deep-sea feeding areas. Little is known about the migration pathways of post-smolts or returning adults. See this mighty fish propel itself, like a dart, up and over the fast-flowing waters of some of our finest rivers in Scotland. These ‘post-smolts’ begin to leave rivers for the sea in late spring, with most fish gone by June.Įach year Atlantic salmon make incredible journeys back from the ocean to return to their breeding grounds. The young fish, now called ‘smolts’, continue to change in appearance, becoming silver. On reaching about 12cm in length, the parr undergo a physiological transformation that lets them survive at sea. The parr will live in the river for two to three years depending on water temperature and food availability. Once the fish have developed markings on their sides, they’re known as ‘parr’. Now about 3cm in length, the fish are known as ‘fry’. The alevins remain in the redd for a few weeks and emerge from the gravel in April or May, having absorbed the yolk sac. The young fish, which still have a yolk sac attached, are called ‘alevins’. How long it takes for eggs to hatch (the incubation time) depends on water temperature. The female then covers the fertilised eggs with gravel. As a female releases her eggs, an adult male (or mature juvenile) immediately fertilises them. ![]() Those that survive may spawn again.įemale fish lay their eggs in gravel depressions known as ‘redds’. About 90 to 95% of all Atlantic salmon die after spawning has taken place. Spawning usually occurs from November to December, but may extend from October to late February in some areas, particularly larger rivers. This means that many ‘populations’ of Atlantic salmon may exist within the same river. They occur in the rivers of the countries that border both sides of the North Atlantic Ocean, and the Baltic Sea.Īs an anadromous species, Atlantic salmon live in freshwater as juveniles but migrate to sea as adults before returning up river to spawn.Ītlantic salmon return to their native river, and even the same stretch of the river from which they were born, with amazing accuracy. Atlantic salmon ( Salmo salar) are found in the temperate and arctic regions of the northern hemisphere. ![]()
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