Abstract:
Ana1ysis of January to March samples of gaper clam larvae from Yaquina Bay, Oregon have established four hypotheses for further testing: 1) gaper clams have an approximately lunar cycle of spawning intensity with maximum production of larvae at the periods of greatest tidal amplitude, 2) the time required for development from 'straight-hinge' to 'umbo' stage is two to three weeks; 3) younger larvae are about evenly distributed through the lower estuary, except that they are less common over the tidal flats of the south shore; and 4) gaper clam larvae are found throughout the water column but are consistently most abundant in near surface depths.
