Swimming behaviour was investigated in adult egg-carrying northern shrimp (Pandalus borealis) exposed to dilute concentrations of the pesticides Alpha Max® (active ingredient deltamethrin) and Salmosan® (active ingredient azamethiphos) used to control parasitic copepods in salmon aquaculture. These treatments are applied topically within fish nets or well boats. Following a short treatment period, the pesticides are directly discharged to sea, exposing non-target organisms such as P. borealis to diluted concentrations of these chemicals. Locomotor activity was measured continuously in individual shrimp over several days within which they were exposed to treatments of diluted AlphaMax® or Salmosan®. Dilutions were based on modelling and dispersion studies from the literature and were considered environmentally realistic for greater than 1 km from point of discharge. 24 h continuous flow treatments were delivered within a 3.5-day monitoring period to observe the timeline of events following the release of treatment water, addressing questions of temporal responses in locomotor activity, recognising key time points of significant events and assessing the survival capacity of the shrimp. Exposure of shrimp to 1 ng l⁻¹ deltamethrin triggered an immediate increase in swimming activity which reduced in intensity over the following 22 h leaving all shrimp either moribund or dead. A further exposure trial exposing shrimp to 0.2 ng l⁻¹ deltamethrin (nominal) showed an increase in activity at the start of exposure that continued throughout the 24 h delivery, returning to previous levels by the end of the 3.5-day monitoring period. All these shrimps survived for at least four weeks after exposure, putting the threshold concentration of deltamethrin leading to immobility or death in adult P. borealis within this study at greater than 0.2 ng l⁻¹ (nominal) and less than 1 ng l ^− 1 (measured). Exposure of P. borealis to azamethiphos at 30 ng l⁻¹ induced several periods of significantly increased activity within the first 10 h of exposure and an extended period of reduced activity during post exposure, though no morbidity was observed with this treatment. No significant increase in activity or morbidity was observed in shrimp during a water vehicle control assessment. Shrimps exposed to a combination of 30 ng l⁻¹ azamethiphos and 1 ng l⁻¹ deltamethrin broadly followed the response pattern shown by shrimp exposed to 1 ng l⁻¹ deltamethrin alone. Pesticide residues were not detected in post exposure tissue analyses for either chemical. The potential ecological significance of increased swimming activity at the start of pesticide exposures is discussed.

在暴露于稀释浓度的杀虫剂 Alpha Max®（活性成分溴氰菊酯）和 Salmosan®（活性成分氮杂甲硫磷）用于控制鲑鱼养殖中的寄生桡足类动物的成年携带卵的北方虾（Pandalus borealis）的游泳行为进行了研究。这些处理在渔网或井船内局部应用。经过短暂的处理后，农药直接排入海中，暴露了非目标生物，如P.borealis稀释这些化学品的浓度。在将虾暴露于稀释的 AlphaMax® 或 Salmosan® 处理的几天内，连续测量个体虾的运动活动。稀释是基于文献中的建模和扩散研究，并且被认为是距排放点 1 公里以上的环境现实。在 3.5 天的监测期内提供 24 小时连续流处理，以观察处理水释放后事件的时间线，解决运动活动的时间响应问题，识别重大事件的关键时间点并评估处理水的存活能力虾。虾暴露于 1 ng l ⁻¹溴氰菊酯引发游泳活动的立即增加，在接下来的 22 小时内强度降低，使所有虾要么垂死要么死亡。将虾暴露于 0.2 ng l ^-1溴氰菊酯（标称值）的进一步暴露试验显示，暴露开始时活性增加，并在整个 24 小时交付期间持续，在 3.5 天监测期结束时恢复到以前的水平。所有这些虾在暴露后至少存活了 4 周，将本研究中导致成年北极虾不动或死亡的溴氰菊酯阈值浓度设置为大于 0.2 ng l ^-1（标称值）和小于 1 ng l  ^{-  1}（测量）。的接触30 ng l ^-1对氮杂甲硫磷的北方疟原虫在暴露的前 10 小时内诱导了几个时期活性显着增加和暴露后活性降低的延长时期，尽管这种处理没有观察到发病率。在水载体控制评估期间，没有观察到虾的活性或发病率显着增加。暴露于 30 ng l ^-1氮杂甲硫磷和 1 ng l ^-1溴氰菊酯组合的虾大致遵循暴露于 1 ng l ^{-1 的}虾所显示的反应模式单独使用溴氰菊酯。两种化学品的暴露后组织分析均未检测到农药残留。讨论了在农药暴露开始时增加游泳活动的潜在生态意义。