Settlement Preference and the Timing of Settlement of the Olympia Oyster, Ostrea lurida, in Coos Bay, Oregon

• Main Author: Sawyer, Kristina M., 1985-
• Format: Thesis
• Language: English
• Published: University of Oregon 2011
• Subjects: Ecology; Conservation; Zoology; Biological sciences; Coos Bay (Or.); Olympia oyster; Ostrea lurida; Settlement; Substratum; Pacific; Crassostrea gigas; Pacific oyster
• Online Access: http://hdl.handle.net/1794/11988

xiii, 86 p. : ill. (some col.) In the Pacific Northwest, populations of the Olympia oyster, Ostrea lurida, were once decimated by overharvesting and natural disasters. Their full recovery may now be limited by availability of hard substrata for larval settlement. I studied the timing of settlement and larval preferences for commonly available substrata, including conspecifics and the shells of Pacific oysters, Crassostrea gigas, which are often provided in restoration efforts. Settlement occurred from August-December with a peak in October. I found no significant settlement differences between live and dead oysters or between shells of Olympia or Pacific oysters. There was significantly higher settlement on bottoms of horizontal substrata than on tops. In the laboratory, larvae showed no clear preferences among various hard substrata. This lack of settlement preference has positive implications for restoration projects, since Pacific oyster shell is much easier to obtain and seems to be no less beneficial than the shells of conspecifics. Committee in charge: Dr. Craig M. Young, Chairperson; Dr. Richard B. Emlet, Member; Dr. Steven S. Rumrill, Member