- By looking at the color: Typically, female salmon are a deeper and duller orange-red when in their spawning habitat whereas the color of the male salmon appears paler.
- By observing the jaws: During spawning when both males and females have strong and enlarged jaws, male salmon develop the kypes - elongations of both lower and upper jaws. Typically, larger salmon will have a more significant increase of the upper jaw which becomes hooked over the tip of the nose. Female salmon might develop slight kypes in some cases, they are small and both jaws grow evenly during spawning time making it look blunter or more round
- By the shape of the body: Female salmon tend to have a deeper and rounder body compared to males which have generally slimmer bodies.