Oogenesis and protandry in the purple-hinge rock scallop, Hinnites giganteus, in upper Puget Sound, Washington, U.S.A.

The annual reproductive cycle of female purple-hinge scallops, Hinnites giganteus, from upper Puget Sound, Washington, U.S.A., was investigated. Gametogenesis occurred in January, vitellogenesis in February, and spawning in June. Spawning was incomplete and development continued until September, but a second spawning did not occur. Based upon wet weight tissues indices, it is proposed that nutrients are stored in the adductor muscle but are transferred to the gonad during the active reproductive season. Phagocytic transfer of nutrients from atretic oocytes probably contributes to gametogenesis. Examination of paraffin sections during February revealed the presence of oocytes in male gonads. Furthermore, female whole body wet weight was significantly greater than male whole body wet weight, and females were more abundant than males. It is suggested that this results from consecutive sexuality, i.e., protandry.