Common inshore, in tide pools or shallow rocky areas, from the intertidal zone to 24 m depth. May remain out of water under rocks or seaweed (Ref. 31184). Feeds mainly on crustaceans and algae. Breathes air (Ref. 31184) and can remain out of water for 15-35 hours if kept moist (Ref. 51276). At somewhere between 5 and 8 cm TL, they shift their diets and feed absolutely on algae, preferring reds and greens (Ref. 43439). Predation by early juvenile fishes on water-column planktors was greatest following initial intertidal settlement and habitat establishment (Ref. 41810). Greater dependence on substrate-oriented and/or benthic prey was exhibited as the fish grew in size (Ref. 41810).
- Martin, K.L.M. and C.R. Bridges 1999 Respiration in water and air. p. 54-78. In M.H. Horn, K.L.M. Martin and M.A. Chotkowski (eds.) Intertidal fishes. Life in two worlds. Academic Press. 399 p. (Ref. 31184) http://www.fishbase.org/references/FBRefSummary.php?id=31184&speccode=6031
I have caught many adults of this species, over a period of at least forty years, while "poke-poling", using mussels for bait. They were caught in Marin County, CA and were as large as approx. 25 inches. That said, I have never found anything in their guts other than algae. I have often wondered if they would be a good candidate for aquaculture because of their diet of algae.