REPRODUCTION AND SURVIVAL OF THE PILEWORMNEREIS SUCCINEAIN HIGHER SALTON SEA SALINITIES

Abstract

The polychaete annelid N. (Neanthes) succinea is the major benthic detritivore in the Salton Sea an inland salt lake in southeastern California [USA], and is critical in the sport fishery trophic chain. In view of the increasing salinity of the Salton Sea, laboratory experiments were conducted to determine critical upper salinity limits for reproduction and survival of pileworms. Atokous (immature) pileworms survive for extended periods in Salton Sea at 65.permill. salinity but there is reduced survival at 70.permill., and only short term survival at 80.permill.. Heteronereid production is depressed by salinities > 50.permill.. Reproduction of N. succinea is successful at salinities as high as 45.permill., and probably as high as 50.permill.. Fertilization and early cleavage stages are less tolerant of elevated salinities than are later development stages such as trochophores.