60 leaves, 7 leaves of plates : ill. ; 28 cm Thesis (M.A.)--University of Oregon, 1943 Bibliography: leaves [51]-53

xi, 134 leaves : ill. ; 28 cm Notes Typescript Thesis (M.A.)--University of Oregon Includes vita and abstract Bibliography: leaves 130-134 Another copy on microfilm is located in Archives

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

xiv, 158 p. / Print copies of this title are available through the UO Libraries under the call number: SCIENCE QL444.M34 D38 2006; OIMB QL444.M34 D38 2006 / The Australasian burrowing isopod (Sphaeroma quoianum) was discovered in Coos Bay, Oregon in 1995. After approximately ten years, S. quoianum has become a common member of the intertidal community and appears to be accelerating shoreline erosion. Surveys, density measurements, and a field experiment were conducted to determine the intertidal distribution, density, and substratum preference of this bioeroder within Coos Bay. Results were compared to two Australian embayments (Port Phillip Bay and the Tamar Estuary) to examine how the ecology of S. quoianum differs. In all bays examined, isopod presence was dependent upon salinity and densities varied between substrata (marsh bank, wood, and friable rock). Densities in marsh banks and friable rock were significantly higher within Coos Bay than the Australian embayments surveyed. In experimental trials, S. quoianum greatly preferred wood to other substrata. The wide distribution and high densities S. quoianum attains have clear environmental and economic implications.