AN ABSTRACT OF THE THESIS OF Amanda C. Amstutz for the degree of Honors Baccalaureate of Science in Zoology presented on June 2, 2009. Title: Effects of Hypoxia on Survival and Growth of Barnacle Larvae Off the Oregon Coast. Abstract approved: ___________

In recent years off the United States Oregon coast severe hypoxic events have resulted in areas of mass vertebrate and invertebrate species mortality known as dead zones. Creation of dead zones and alteration of community species composition in response to inner shelf hypoxic conditions have been observed annually from 2002 to 2007. Near shore hypoxic events have already begun to redefine ecosystems off the Oregon Coast and other areas in the California Current Large Marine Ecosystem (CCLME). Barnacle species are of great importance in these communities. As a part of the life history of the barnacle, successful growth and survival of larval stages is essential to the success of sessile adults. We carried out experiments at Oregon State University's Hatfield Marine Science Center to determine the rate of nauplii (larvae) mortality in the barnacle species Balanus glandula at increasingly severe levels of hypoxia. We also investigated the effects of exposure to hypoxic conditions on B. glandula larval development. We found no difference in nauplii survival or development between exposure to normoxic (5.5 mg/L dissolved oxygen) and microxic (0.5 mg/L dissolved oxygen) conditions for 24 hours. Key Words: Balanus glandula, hypoxia, dead zones, larval developmen