Instructions
Examine the salmon's mouth. In the male, the tip of the mouth will be hooked upwards from the lower jaw. This is called a kype. Only males will have a kype, which is used to fight with other males for spawning rights as well as in certain courtship rituals.
Look for a hump on the salmon's back. In certain species, most notably the pinks and the sockeye, the male salmon will develop a distinctive and pronounced hump on his back.
Examine the salmon for any bright coloration. In some species of salmon, such as the sockeye, the male salmon exhibits a distinctive red coloration that is much brighter than that in the female. Bright colorful spots on the side of any species of salmon denote a male. As in most animal species, bright coloration of any kind usually denotes a male.
Look at the size of the head. The female salmon will have what appears to be a "normal" sized head, whereas the male salmon will have a head that appears slightly too large for its body, and it's head will be longer with more of a pointed jaw.
How to Identify a Male Salmon From a Female Salmon
Discerning a male from a female salmon can be difficult depending on the species of salmon you're looking at and the time of year-during winter months it is almost impossible to tell them apart--but in the late summer months, there are distinctive characteristics that set the male salmon apart from the female.