Copepod swimming behavior is governed by chemical and hydro-mechanical cues. The environment of copepods, however, is frequently impacted by anthropogenic activities, in particular increased levels of suspended sediment due to coastal development. To better understand the effects of sediments on copepod behavior, we used video recordings to document free-swimming in Acartia tonsa under five sediment regimes, both with and without food. Results of the video analysis indicate that as sediment concentration increased, jumping increased and swimming paths became more convoluted. In the presence of prey, swimming trajectories became circular, as opposed to without prey, where paths were more erratic and slower. There was a reverse trend at higher sediment concentrations (120 and 200 mg l⁻¹) for net velocity, turning rate and “spread of participation” index, which could indicate a behavioral threshold. Overall, greater motility with increasing sediment concentration suggests that the copepods were trying to transport themselves out of the sediment-affected area. In the absence of food, the energy cost of this behavior may affect the fitness of Acartia tonsa and, consequently, its predators.

中文翻译：

---

悬浮沉积物对类an足类pe足类动物游泳行为的影响

pe足类的游泳行为受化学和水力机械提示的支配。但是，of足类动物的环境经常受到人为活动的影响，特别是由于沿海开发而导致悬浮泥沙含量增加。为了更好地了解沉积物对co足类行为的影响，我们使用了录像记录了有食和无食的五种沉积物条件下A螨的自由游动。视频分析的结果表明，随着沉积物浓度的增加，跳跃增加，泳道变得更复杂。在存在猎物的情况下，游泳轨迹变成圆形，而不是没有猎物，后者的路径更不稳定且更慢。较高的沉积物浓度（120和200 mg l ^-1）的净速度，转身率和“参与程度”指数，这可能表示行为阈值。总体而言，随着沉积物浓度的增加，运动性增强，表明pe足类试图将自身运出受沉积物影响区域。在没有食物的情况下，这种行为的能源成本可能会影响tons菜的适应性，进而影响其天敌。