Feeding of underyearling walleye surfperch,Hyperprosopon argenteum,in a Northern California Bay

A study of the feeding of underyearling walleye surfperch (Hyperprosopon argenteum) was based on fish collected in seven areas of Humboldt Bay, California, during September and October 1969. Crustaceans were found in all stomachs containing food, but the type of major food consumed varied with distance from the entrance channel. Amphipods were universally consumed, with cypris stages more important in areas with high tidal exchange, and terrestrial moth flies (Psychoda spp.) and harpacticoid copepods more important in backwater areas. Collections indicate daylight feeding and probably limited diurnal movements of underyearling walleye surfperch, a different pattern of feeding behavior than walleye surfperch of inshore waters of southern California.