The eastern oyster Crassostrea virginica is an ecologically and economically important species that is vulnerable to oil pollution. We assessed sublethal effects of soluble fractions of crude oil alone (WAF) and crude oil in combination with Corexit 9500 dispersant (CEWAF) on oysters at three life history stages. Veliger swimming, pediveliger settlement, and adult clearance rates were quantified after 24 h exposures to the contaminants. Veliger swimming speeds were not significantly impacted by 24 h exposures to WAF or CEWAF. A larger proportion of veligers were inactive following WAF and CEWAF exposure as compared to the control, but the effect was greater for pediveligers, and pediveliger settlement in the highest concentration CEWAF treatment decreased by 50% compared to controls. Thus, pediveligers may be particularly vulnerable to oil exposure. In the adults, we found significant clearance rates reductions that persisted 33 days after acute exposure to CEWAF. Knowledge of sublethal effects of oil and dispersant at multiple life history stages aids understanding of how this important species will respond to an oil spill.

中文翻译：

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原油和化学分散剂对东部牡蛎（Crassostrea virginica）的多个生命历史阶段的亚致死作用

东部牡蛎Crassostrea virginica是在生态和经济上很重要的物种，容易受到石油污染。我们评估了原油的单独可溶性部分（WAF）和原油与Corexit 9500分散剂（CEWAF）组合在三个生命历史阶段对牡蛎的亚致死作用。在接触污染物24小时后，对Veliger游泳，swimming行定居和成年清除率进行了量化。Veliger游泳速度不受WAF或CEWAF暴露24小时的影响不大。与对照组相比，WAF和CEWAF暴露后大量的veligers失活，但对减持剂的影响更大，并且在最高浓度的CEWAF处理中，减持剂的沉降与对照组相比减少了50％。因此，减肥药可能特别容易受到油脂的侵害。在成年人中 我们发现，在急性暴露于CEWAF后33天内，清除率一直持续下降。了解油和分散剂在多个生命历史阶段的亚致死作用有助于了解这一重要物种将如何应对溢油。