Floods in June 2013 affected significant portions of the Czech Republic (total damages amounted ~600 millions of euro). This study examines the impact of catastrophic flood on the species composition and size of fish prey in the diet of the common kingfisher (Alcedo atthis), a fish-eating bird, nesting and hunting on Botič stream (Prague, Czech Republic) in 2013. Hundred and forty years water (flow 74.5 m³ s⁻¹) caused considerable damage to property and it is likely that the character and size composition of biota, especially fish, changed. This should be reflected naturally in the diet of resident kingfishers. The diet of kingfishers before and after the flood were investigated from the mass of regurgitated pellets, which were collected from the nest tunnel and chamber immediately after the successful breeding period before and after the flood event. Before the flood (normal situation; flow 0.4–1.5 m³ s⁻¹), the average length of fish caught was 6.5 cm L_T (total length), average weight 2.6 g, and the index of food diversity was 1.58. After the flood, the average length of fish caught was 7.5 cm L_T, weight 4.1 g, and the index of the food diversity was 1.36. It was evident that after the flood kingfishers were forced to hunt significantly larger prey. Six fish species (Gobio gobio, Squalius cephalus, Perca fluviatilis, Scardinius erythrophthalmus, Rutilus rutilus, Pseudorasbora parva) which were hunted both before and after the flood composed 96.5 and 99.8% of the catch (by numbers). Surprisingly, the impact of floods may not always be reflected in the species composition of the diet of fish-eating birds, it mostly depends on the presence of fish broadly occurring in the stream, natural stability of the fish stock and on the composition of the fish assemblage in the upstream catchment area.

2013年6月的洪灾影响了捷克共和国的大部分地区（总损失约6亿欧元）。这项研究调查了2013年常见洪水，捕食鸟的普通翠鸟（Alcedo atthis）的饮食对大洪水的影响，该洪水对普通翠鸟（Alcedo atthis）的种类组成和捕食规模的影响。一百四十年的水（流量74.5 m ³  s ^-1）对财产造成了相当大的损害，很可能会改变生物区系的特征和大小组成，尤其是鱼类。这应该在常驻翠鸟的饮食中自然反映出来。通过在水灾前后成功繁殖期后立即从巢穴和巢室收集的反潮颗粒的数量来研究洪灾前后翠鸟的饮食。在洪灾之前（正常情况；流量为0.4–1.5 m ³  s ^-1），捕获的鱼的平均长度为6.5 cm L _T（总长度），平均重量为2.6 g，食物多样性指数为1.58。洪水后，平均捕获的鱼长为7.5 cm L _T，重量为4.1克，食物多样性指数为1.36。显然，洪水过后，翠鸟被迫捕猎更大的猎物。6种鱼类（Gobio gobio，Squalius cephalus，Perca fluviatilis，Scardinius erythrophthalmus，Rutilus rut​​ilus，Pseudorasbora parva）在洪水前后被捕的数量占渔获量的96.5和99.8％（按数字）。令人惊讶的是，洪水的影响可能并不总是反映在以鱼为食的鸟类饮食的物种组成中，它主要取决于广泛存在于河流中的鱼的存在，鱼群的自然稳定性以及鱼群的组成。上游集水区的鱼类聚集。