Sockeye salmon are blue tinged with silver in color while living in the ocean. When they return to spawning grounds, their bodies become red and their heads turn green. Sockeye can be anywhere from in length and weigh from . Two distinguishing features are their long, serrated gill rakers that range from 30 to 40 in number, and their lack of a spot on their tail or back. Sockeye salmon range as far south as the Columbia River in the eastern Pacific (although individuals have been spotted as far south as the 10 Mile River on the Mendocino Coast of California) and
Kokanee salmon of landlocked sockeye has occurred more than once with different kokanee populations, showing genetic differences between populations. Most evidence points to events that land-locked the lake-type sockeye (which spawns in streams and lakes, rather than tributaries like the sea-type sockeye, but is still anadromous and spends most of its adult life out at sea), which evolved into the non-anadromous form. Genetic evidence from kokanee in the Fraser River drainage and Columbia River drainage shows that ancestors of the kokanee came from the lake-type sockeye. The data also suggests that the kokanee may have evolved back into a lake-type anadromous form