Total lengths corresponding to the male and female ages were 15.0 in. and 17.4 in., respectively. The largest recorded size is 21 in. Approximately one third of all male kelp greenling are sexually mature at age 2, while half of all males are mature by age 3-4 at an average total length of 11.6 inches. Approximately one half to two thirds of all females kelp greenling are sexually mature at age 3-4 at an average total length of 11.6 inches. In California, the spawning season for kelp greenling occurs from September through December.
Females spawn their eggs subtidally on rocks.
Their egg nests have been observed at depths of 16 to 56 feet. An individual male kelp greenling may guard up to 11 egg masses simultaneously, although the average number is four. Hatching occurs from December through February in northern California. Larvae are approximately 0.3 to 0.4 in. Natural Mortality Estimates of natural mortality are not available.