Johnson K B, Brink L A
Biol Bull. 1998 Jun;194(3):297-303. doi: 10.2307/1543099.
Polychaete larvae from several families are thought to be natural predators upon planktonic bivalve larvae. However, little direct evidence of interactions between these predators and prey is available. We conducted predator-prey experiments on laboratory roller tables for five putative predatory polychaete larvae, representing four families (metatroch-less larvae of the Polynoidae and metatrochophore larvae of the Spionidae, the Magelonidae, and the Phyllodocidae). D-hinge veliger larvae of the oyster Crassostrea gigas were offered as prey. Predation was monitored over a range of prey densities and in the presence and absence of background plankton. "Background plankton" are any naturally occurring plankton assemblages found in whole, unfiltered seawater at ambient concentrations. For all polychaete larvae examined, when natural C. gigas densities and background plankton were used, no predation was observed. Magelonids and phyllodocids did not consume any C. gigas larvae, regardless of conditions. Polynoid and spionid trochophores consumed C. gigas veligers at both the "natural" and unnaturally high prey densities in filtered seawater. The addition of background plankton eliminated the predation at all natural prey densities and significantly reduced the predation observed at high prey densities.
几个科的多毛类幼虫被认为是浮游双壳类幼虫的天然捕食者。然而，关于这些捕食者与猎物之间相互作用的直接证据却很少。我们在实验室的旋转台上对五种假定的捕食性多毛类幼虫进行了捕食者 - 猎物实验，它们代表了四个科（多鳞虫科无后纤毛幼虫以及沙蚕科、长手沙蚕科和叶须虫科的后纤毛幼虫）。以牡蛎巨蛎的D形铰合面幼虫作为猎物。在一系列猎物密度条件下，以及有和没有背景浮游生物的情况下监测捕食情况。“背景浮游生物”是指在未经过滤的天然海水中以环境浓度存在的任何自然浮游生物组合。对于所有检测的多毛类幼虫，当使用天然的巨蛎密度和背景浮游生物时，未观察到捕食现象。无论条件如何，长手沙蚕科和叶须虫科的幼虫都不捕食任何巨蛎幼虫。多鳞虫科和沙蚕科的担轮幼虫在过滤海水中，无论是“天然”猎物密度还是人为提高的猎物密度下，都会捕食巨蛎的面盘幼虫。添加背景浮游生物消除了在所有天然猎物密度下的捕食现象，并显著降低了在高猎物密度下观察到的捕食情况。
