Amphibian populations are declining worldwide at alarming rates. Among the large variety of contributing stressors, chemical pollutants like pesticides have been identified as a major factor for this decline. Besides direct effects on aquatic and terrestrial amphibian stages, sublethal effects like impairments in reproduction can affect a population. Therefore, we investigated the reproductive capacity of common toads (Bufo bufo) in the pesticide-intensive viticultural landscape of Palatinate in Southwest Germany along a pesticide gradient. In a semi-field study, we captured reproductively active common toad pairs of five breeding ponds with different pesticide contamination level and kept them in a net cage until spawning. Toads from more contaminated ponds showed an increased fecundity (more eggs) but decreased fertilization rates (fewer hatching tadpoles) as well as lower survival rates and reduced size in Gosner stage 25, suggesting that the higher exposed populations suffer from long-term reproductive impairments. In combination with acute toxicity effects, the detected sublethal effects, which are mostly not addressed in the ecological risk assessment of pesticides, pose a serious threat on amphibian populations in agricultural landscapes.

全球两栖动物数量正在以惊人的速度下降。在众多造成压力的因素中，杀虫剂等化学污染物已被确定为造成这种下降的主要因素。除了对水生和陆生两栖动物阶段的直接影响外，生殖损伤等亚致死效应也会影响种群。因此，我们沿着农药梯度调查了德国西南部普法尔茨农药密集型葡萄栽培景观中常见蟾蜍（ Bufo bufo ）的繁殖能力。在一项半田间研究中，我们在五个不同农药污染水平的养殖池中捕获了繁殖活跃的普通蟾蜍对，并将它们放在网笼中直至产卵。受污染程度较高的池塘中的蟾蜍在 Gosner 25 阶段表现出繁殖力增加（更多卵）但受精率下降（孵化蝌蚪更少）以及较低的存活率和较小的体型，这表明较高程度的暴露种群遭受长期生殖损害。与急性毒性效应相结合，检测到的亚致死效应对农业景观中的两栖动物种群构成严重威胁，而这些效应在农药的生态风险评估中大多没有得到解决。