Document Type

Master's Thesis

Degree Name

Master of Science (M.S.)


Moss Landing Marine Laboratories


The aims of this study were to quantify the kinematics of two feeding behaviors exhibited by G. nigricans. A scraping behavior was elicited by allowing G. nigricans to scrape from a block of brine shrimp gelatin and a picking behavior was elicited by allowing G. nigricans to feed on Ulva spp. During feeding events it became apparent that G. nigricans does not use, or has lost, the ability to suction feed. When feeding on non-attached diet items they approached their prey with their gape wide open until the prey was in their mouth, likely to reduce the bow wave created in the water. The lack of suction during feeding and the presence of the IMJ has led to the conclusion that G. nigricans is a specialized scraper. Further comparisons were made with species in the same family. These comparisons suggested that the opaleye is a specialized scraper.


Thesis (M.S.) Division of Science and Environmental Policy. Moss Landing Marine Laboratories