Light stimulates swimming behavior of larval eastern oysters Crassostrea virginica in turbulent flow
Light stimulates swimming behavior of larval eastern oysters Crassostrea virginica in turbulent flow
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光刺激东部牡蛎幼体在湍流中的游泳行为
DOI：
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发表时间：
2017
期刊：
影响因子：
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通讯作者：
L. Mullineaux
中科院分区：
文献类型：
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作者：
J. Wheeler;Elaine Luo;K. Helfrich;E. Anderson;V. Starczak;L. Mullineaux
：东部牡蛎 Crassostrea virginica 的浮游幼虫能够调节其在水中的垂直位置，但负责这种调节的环境因素，特别是在湍流环境中，仍不清楚。我们量化了网格搅拌湍流池中晚期牡蛎幼虫的游泳反应，以确定在类似于自然沿海环境的一系列水动力条件下，光如何影响幼虫的游泳行为。我们使用粒子图像测速和幼虫跟踪将幼虫游泳与局部流动隔离，并量化 3 个行为指标：垂直游泳方向、幼虫潜水比例和螺旋游泳比例。我们在明亮和黑暗的情况下比较了从静水 (ε = 0 cm 2 s -3 ) 到河口状条件 (ε = 0.4 cm 2 s -3 ) 的湍流水平的这些指标。在所有湍流水平下，光对向上游泳的幼虫的比例没有影响，但引起螺旋游泳和潜水行为的比例明显增加。我们进一步研究了光和湍流对螺旋轨迹特定特征的影响，发现这些环境因素会引起螺旋游动幼虫垂直和水平速度的变化，从而改变螺旋几何形状。这些行为在光下的普遍性增加可能发挥了生态作用：光下潜水的增加（与湍流相结合）是提高定居成功率的潜在机制，而光下螺旋游动的变化可能起到反捕食的作用。总之，这些行为提供了对幼虫对多个同时发生的环境线索的潜在复杂反应的深入了解。
: Planktonic larvae of the eastern oyster Crassostrea virginica are able to regulate their vertical position in the water, but the environmental cues responsible for this regulation, par-ticularly in turbulent settings, remain unclear. We quantified swimming responses of late-stage oyster larvae in a grid-stirred turbulence tank to determine how light affects the swimming behavior of larvae over a range of hydrodynamic conditions similar to their natural coastal environ-ments. We used particle image velocimetry and larval tracking to isolate larval swimming from local flow and to quantify 3 behavioral metrics: vertical swimming direction, proportion of larvae diving, and proportion of larvae swimming helically. We compared these metrics across turbulence levels ranging from still water ( ε = 0 cm 2 s −3 ) to estuarine-like conditions ( ε = 0.4 cm 2 s −3 ) in light and dark. At all turbulence levels, light had no effect on the proportion of upward swimming larvae, but elicited detectable increases in the proportion of helical swimming and diving behaviors. We further examined the effect of light and turbulence on specific characteristics of helical trajectories, and found that these environmental cues induce changes to both vertical and horizontal velocities of helically swimming larvae, changing the helix geometry. The increased prevalence of these behaviors in light likely plays an ecological role: increased diving in light (in conjunction with turbulence) is a potential mechanism to enhance settlement success, while changes to helical swimming in light may serve an anti-predatory function. Together, these behaviors pro-vide insight into potentially complex larval responses to multiple simultaneous environmental cues.