02366nas a2200229   4500008004100000050008800041245015300129210006900282250001000351260005000361300001100411520148300422653004101905653001101946653001301957653001601970653001401986653001102000653001002011100002502021856009002046       1977                        eng d  aOSU Libraries: Internet Resources LD4330 1978 .R35, Guin Ratti, Digital Open Access00aReproduction and Growth of the Pacific Basket-Cockle, <i>Clinocardium nuttallii </i>Conrad, from Intertidal and Subtidal Environments of Netarts Bay0 aReproduction and Growth of the Pacific BasketCockle iClinocardiu  aM. S.  aCorvallis, Or.bOregon State Universityc1977  a116 p.3 aAge structure and growth of shells of the Pacific basket-cockle, Clinocardium nuttallii in Netarts Bay, Oregon, were investigated with special emphasis on the differences between subtidal and intertidal populations. The cockle was chosen for study because its growth is highly sensitive to physical factors in the environment. Evidence is presented which suggests that stresses of the physical environment and biological factors result in oldest individuals being in the subtidal, and that growth of shells is correlated with the amount of tidal submergence. A short-term tagging study was done at two sites and most of yearly growth occurred in the Spring months. Collections were made from July, 1975, through September, 1976, from six sites to study synchronism of gonadal development and fecundity of populations by histological examination of gonads. Synchronism of gonadal development to the ripe stage occurs among intertidal and subtidal populations in the same area, while populations from different areas of the bay do not reach the ripe condition at the same time. There is evidence of protandric spawning behavior, and the hermaphroditic nature of C. nuttallii is compared to that of the Family Tridacnidae. The fecundity of the subtidal populations, in terms of percentages of the populations producing ripe gonads, was greater than fecundity of the intertidal populations. The subtidal environment is suggested to serve as 'refugia' for adult breeding populations.10aCockle clam = Clinocardium nuttallii10agrowth10ahabitats10aNetarts Bay10ashellfish10atheses10atides1 aRatti, Frank Douglas  uhttps://ir.library.oregonstate.edu/concern/graduate_thesis_or_dissertations/ng451m556