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Impact of catastrophic flood on the species and size composition of the diet of kingfisher (Alcedo atthis)
Hadravová, Alena ; Čech, Martin (advisor) ; Porkert, Jiří (referee)
A B S T R A C T This study examines the impact of catastrophic flood on the species com- position and size of fish prey in the diet of kingfisher (Alcedo atthis) nest- ing in Prague's Botič stream in 2013. Floods in June 2013 affected mainly Bohemia and partly Moravia. The streams across the Vltava river basin, in part of the Elbe river basin and marginally in the Thaya river got swollen. The effect of the flood on the Botič stream was further ampli- fied by draining of water from the dam Hostivař. Hundred and forty year water caused considerable damage to property and it is likely that it also changed the character and size composition of biota, especially fish. This change should be reflected naturally in the diet of kingfisher, which nests and hunts here. The species composition and size of fish prey in the diet of kingfisher before and after the catastrophic flood was investigated from the mass of regurgitated pellets collected from nest tunnels and chambres. In the nesting sediment, 689 head diagnostic bones (pharyngeal bones - ossa pharyngea and preopercual bones - praeoperculare) were found before the flood on Botič stream in June 2013. These bones belonged to 10 fish species and 3 families (Cyprinidae, Percidae and Balitoridae). The average length of fish was 6,5 cm, average weight 2,6 g, and the index of...
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