Masu Salmon Identification Guide

Key identification features

• Streamlined body, silvery in the sea-run form and olive-brown with dark oval parr marks in the freshwater-resident yamame form
• Small black spots scattered along the back and dorsal fin
• Retains dark, oval parr-like markings along the lateral line even as an adult, unlike most Pacific salmon
• Relatively small size compared to other Pacific salmon species
• Moderately forked tail and a small adipose fin

Common look-alikes

• Cherry salmon: the same species; cherry salmon typically refers to the sea-run adults that turn reddish-pink at spawning, while masu salmon is used more broadly for the species, including the smaller, non-migratory yamame form
• Rainbow trout or steelhead: shows a pink lateral band and heavier, denser black spotting rather than persistent oval parr marks
• Chum salmon: much larger, developing faint purple bars at spawning but lacking retained parr marks

Where you'll see one

Masu salmon occur in coastal rivers and streams of Japan, Korea, and the Russian Far East, with some populations migrating to sea and returning to spawn while others, the yamame, remain resident in cool headwater streams their entire lives.