The only salmon in the Salmonidae family that occurs in the Atlantic Ocean and its tributaries, the Atlantic salmon has been coveted for its excellent ﬂesh since recorded history.
IdentificationCompared to the size of its body, a mature Atlantic salmon has a small head. Its body is long and slim, and in adults the caudal or tail ﬁn is nearly square. Individuals that return to spawn prematurely (called grilse) are mostly males and have slightly forked tails. At sea, the Atlantic salmon is dark blue on top of its head and back; its sides are a shiny silver, and the belly is white.
The ﬁns are dark, and there are numerous black marks in the shape of an X or a Y on its head and along its body above the lateral line. When the ﬁsh enters freshwater to spawn, it gradually loses its metallic shine and becomes dull brown or yellowish.