Steel Anna E, Baird Sarah E, Cocherell Dennis E, Young Thomas M, Connon Richard E, Fangue Nann A
Department of Wildlife, Fish, and Conservation Biology, University of California, Davis, One Shields Ave, Davis, CA, 95616 USA.
Department of Civil and Environmental Engineering, University of California, Davis, One Shields Ave, Davis, CA, 95616 USA.
Conserv Physiol. 2025 Jul 30;13(1):coaf055. doi: 10.1093/conphys/coaf055. eCollection 2025.
The presence of chemical contaminants in freshwater systems poses a threat to many aquatic organisms, and understanding the extent and nature of this threat can facilitate conservation management actions. Sturgeon are considered threatened worldwide and they differ in many important ways from other fishes. Two sturgeon species, green sturgeon () and white sturgeon (), are found in California and utilize anthropogenically impacted freshwater habitats of the Central Valley. This study evaluated the behavioural effects in endogenously feeding larvae (3-7 days post hatch) of both sturgeon species following an acute exposure (96 hours) to the pyrethroid pesticide bifenthrin at aqueous concentrations ranging from 10 to 2000 ng/l, with selected levels based on previous environmental monitoring. Sturgeon had high survival at all concentrations tested (~95%), yet at higher concentrations (>1000 ng/l) they displayed altered behavioural patterns, including reduced activity, increased meander of the movement path and reduced thigmotaxis. While these higher concentrations of bifenthrin have been observed within water samples from the sturgeon habitats of California, they appear uncommon. The present study suggests that sturgeon larvae are not highly sensitive to acute aqueous exposure under environmentally relevant concentrations of bifenthrin (1-10 ng/l), yet these aqueous concentrations do have behavioural effects that may be of concern for the conservation of these declining species. Additionally, impacts to these species may also occur through exposure to sediment-bound bifenthrin or dietary bioaccumulation, and more work needs to be done to understand the implications of these exposure routes.
淡水系统中化学污染物的存在对许多水生生物构成威胁，了解这种威胁的程度和性质有助于采取保护管理行动。鲟鱼在全球范围内被视为受威胁物种，它们在许多重要方面与其他鱼类不同。两种鲟鱼，绿鲟（）和白鲟（），分布于加利福尼亚州，并利用中央谷地受人为影响的淡水栖息地。本研究评估了两种鲟鱼内源性摄食幼虫（孵化后3 - 7天）在急性暴露（96小时）于拟除虫菊酯类农药联苯菊酯（浓度范围为10至2000纳克/升，选定水平基于先前的环境监测）后的行为影响。在所有测试浓度下鲟鱼的存活率都很高（约95%），然而在较高浓度（>1000纳克/升）时，它们表现出行为模式改变，包括活动减少、运动路径曲折度增加和趋触性降低。虽然在加利福尼亚州鲟鱼栖息地的水样中已观察到这些较高浓度的联苯菊酯，但它们似乎并不常见。本研究表明，在与环境相关的联苯菊酯浓度（1 - 10纳克/升）下，鲟鱼幼虫对急性水体暴露不太敏感，但这些水体浓度确实会产生行为影响，这可能关乎这些数量正在减少的物种的保护。此外，通过接触与沉积物结合的联苯菊酯或饮食生物累积也可能对这些物种产生影响，需要开展更多工作来了解这些暴露途径的影响。
