Seymour, John Patrick2022-07-062022-07-061987-06https://hdl.handle.net/1794/2723274 pagesThis was the first diet study on the shiner surfperch and the staghorn sculpin in the Umpqua River Estuary, Oregon. Gammarid amphipods, teleosts, and ghost shrimp were the most important food items of the staghorn sculpin whereas barnacle cypris larvae, cancer crab megalops, and copepods were the main components of the shiner surfperch diet. Only large staghorn sculpins ate teleosts, whereas only the smaller ones ate isopods. This study supports literature reporting a change in sculpin diet with size. Staghorn sculpins ate larger prey if they were larger. Monophagous foraging by the shiner surfperch was found with cancer crab megalops and crab zoea. Adequate sample sizes for future studies were determined.enCreative Commons BY-NC-ND 4.0-USMarine BiologyShiner SurfperchCymatogaster aggregata GibbonsStaghorn SculpinLeptocottus armatus GirardThesis / Dissertation