Book excerpt: Growth, reproduction, food habits, and parasites of pile perch were investigated in Yaquina Bay, Oregon between April 1966 and July 1967. The research disclosed that pile perch live at least 10 years. Males and females of given ages are close to the same size up to age IV, after which females are increasingly larger than males. The diet varies between seasons and localities. Pile perch are carnivorous feeders, obtaining food from the bottom or protruding surfaces in the littoral zone. Principal foods are barnacles, mussels, the bay clams, crabs, mud shrimp and tube dwelling amphipod. None of the pile perch examined was heavily parasitized. Infestations of gill copepods vary seasonally.