Adult Interference with Postlarvae in Soft Sediments: The Pontoporeia-Macoma Example

摘要: In the Baltic Sea, presence of dense populations deposit-feeding amphipods Pontoporeia affinis and P. femorata has been hypothesized to inhibit recruitment bivalve Macoma balthica. Experimental tests with newly settled M. balthica in small, flow- through aquaria corroborated this hypothesis. Survival small spat decreased increasing density affinis. The increase mortality was strong enough potentially explain field observation that is generally absent or rare areas spp. Three hypotheses as mechanism for survival were tested. results inconsistent suffocation after burial starvation death, but hypothesis direct physical injury following contact afiinis adults. affinis, lower shallow than deep sediment; encounters between two species should be more frequent sediment. Adult found crush spat, presumably ingesting remains. are not, however, common an important food source afiinis. It suggested while interference larval by adults likely structuring factor marine soft bottom communities, it unlikely depress community biomass below carrying capacity, Peterson (1979). Virtually all communities contain brood protection, young which less susceptible Where such strong, protection become dominant, over large Sea.