Ruggiero Kaue Leopoldo Ferraz, da Silva Pinto Thandy Júnio, Gomes Diego Ferreira, Dias Mariana Amaral, Montagner Cassiana Carolina, Rocha Odete, Moreira Raquel Aparecida
NEEA/SHS and PPG-SEA, São Carlos School of Engineering, University of São Paulo, Av. Trabalhador São Carlense, 400, São Carlos, 13560-970, Brazil.
Analytical Chemistry Department, Institute of Chemistry, University of Campinas, Campinas, São Paulo, Brazil.
Arch Environ Contam Toxicol. 2024 Feb;86(2):112-124. doi: 10.1007/s00244-024-01052-2. Epub 2024 Jan 24.
Predation presents specific behavioral characteristics for each species, and the interaction between prey and predator influences the structuring of the food web. Concerning insects, predation can be affected in different ways, such as exposure to chemical stressors, e.g., pesticides. Therefore, analyses were carried out of the effects of exposure to insecticide fipronil and the herbicide 2,4-D on predation, parameters of food selectivity, and the swimming behavior of two neotropical predatory aquatic insects of the families Belostomatidae (giant water bugs) and larvae of Libellulidae (dragonfly). These predatory insects were exposed for 24 h to a commercial formulation of the chlorophenoxy herbicide, 2,4-D at nominal concentrations of 200, 300, 700, and 1400 μg L, and to a commercial formulation of the phenylpyrazole insecticide, fipronil at nominal concentrations of 10, 70, 140, and 250 µg L. In a control treatment, the insects were placed in clean, unspiked water. At the end of the exposure, the maximum swimming speed of the predators was evaluated. Afterward, the predators were placed in clean water in a shared environment for 24 h with several prey species, including the cladoceran Ceriodaphnia silvestrii, larvae of the insect Chironomus sancticaroli, the amphipod Hyalella meinerti, the ostracod Strandesia trispinosa, and the oligochaete Allonais inaequalis for 24 h. After this period, the consumed prey was counted. The results reveal that predators from both families changed prey consumption compared with organisms from the control treatment, marked by a decrease after exposure to fipronil and an increase in consumption caused by 2,4-D. In addition, there were changes in the food preferences of both predators, especially when exposed to the insecticide. Exposure to fipronil decreased the swimming speed of Belostomatidae individuals, possibly due to its neurotoxic effect. Exposure to the insecticide and the herbicide altered prey intake by predators, which could negatively influence the complex prey-predator relationship and the functioning of aquatic ecosystems in contaminated areas.
捕食行为对每个物种都呈现出特定的行为特征，猎物与捕食者之间的相互作用会影响食物网的结构。对于昆虫而言，捕食行为可能会受到不同方式的影响，例如接触化学应激源，如杀虫剂。因此，本研究分析了接触杀虫剂氟虫腈和除草剂2,4-滴对两种新热带地区捕食性水生昆虫（负子蝽科（巨型水蝽）和蜻蛉科幼虫（蜻蜓））的捕食行为、食物选择性参数以及游泳行为的影响。这些捕食性昆虫在24小时内分别暴露于氯苯氧基除草剂2,4-滴的商业制剂中，其标称浓度分别为200、300、700和1400微克/升，以及苯基吡唑类杀虫剂氟虫腈的商业制剂中，其标称浓度分别为10、70、140和250微克/升。在对照处理中，将昆虫置于清洁、未添加药剂的水中。暴露结束后，评估捕食者的最大游泳速度。之后，将捕食者置于一个共享环境的清洁水中24小时，水中有几种猎物，包括枝角类的西尔维斯特裸腹溞、昆虫圣卡洛斯摇蚊的幼虫、双甲目动物梅氏透明钩虾、介形纲动物三刺斯特兰德介以及寡毛纲动物不等阿洛纳蚓，持续24小时。在此期间过后，统计被消耗的猎物数量。结果表明，与对照处理中的生物相比，两个科的捕食者的猎物消耗量均发生了变化，其特征是接触氟虫腈后消耗量减少，而2,4-滴导致消耗量增加。此外，两种捕食者的食物偏好也发生了变化，尤其是在接触杀虫剂时。接触氟虫腈会降低负子蝽科个体的游泳速度，这可能是由于其神经毒性作用。接触杀虫剂和除草剂会改变捕食者的猎物摄入量，这可能会对受污染地区复杂的猎物-捕食者关系以及水生生态系统的功能产生负面影响。
