Migration of the sandworm Nereis virens during winter nights

摘要: There have been many previous reports of the sandworm Nereis virens Sars swimming in water column. This behavior usually has attributed to reproductive processes. Sandworms were found surface waters at night on ebb tides during nights January, February and March a Maine (USA) estuary. None specimens examined contained gametes or possessed other characteristic spawning pre-spawning modifications. Several age classes found, with worms measuring 9 38 cm length, weighing 0.5 19.8 g, having 82 187 segments. The greatest numbers observed near-average evenings which low occurred few hours after sunset but prior moonrise. Up 83 per minute seaward through 20 m transect, while none landward any stage tide. It is concluded that sandworms winter unrelated reproduction it an inherent pattern.