Young fish have four dark vertical bands on their sides which gradually fade into dusky blotches as they increase in size. Their heads are large and spined, the dorsal fins are deeply notched, and there is an unusually wide space between the eye and the upper jaw. These three characteristics help to distinguish cowcod from other reddish colored rockfish. Cowcod are found over rocky bottoms, particularly where there are sharp, steep drop-offs. The diet of the cowcod includes mainly fishes, octopus, and squid.
Juvenile cowcod eat small shrimp and crabs.
Like all members of the genus Sebastes, the cowcod gives birth to live young. These are less than 0.5 inches in length and are produced in great numbers. Live squid and oversized metal, lead and rubber jigs are often effective baits for this species. Live or salted anchovies or frozen squid are also considered good baits for the cowcod. Sometimes cowcod are caught while attacking smaller rock fish which have already been hooked and are being brought to the surface.