Justyna Chachulska, Katarzyna Turzańska, Marta Borowiec
Ornis Polonica 2014, 55: 227–239
https://doi.org/10.12657/ornis.2014.4.0
Abstract: The paper summarizes knowledge about several aspects of breeding biology of the Whitethroat Sylvia communis, based on analysis of data from 408 nest cards collected between 1987 and 2013 in the Polish Nest Record Scheme. This species has not been studied in detail in Poland yet. Over half of the data were collected from Masovian, Lower Silesian and Silesian voivodeships. The nests were found most often in the agricultural landscape, on semi-open areas, densely overgrown by shrubs and herbaceous vegetation. They were usually placed low, in over half of cases between 0.2 and 0.6 m above the ground (range 0–4 m). The earliest broods were laid in the second half of April, while the latest in the second half of July, with the majority laid during the second half of May. Whitethroats laid 3–6, predominantly 5 or 6 eggs, and the mean clutch size was 5.1. The clutch size decreased with the progress of the breeding season. The breeding success was 51%. 21% of the nests containing eggs and 25% nests with the nestlings were destroyed. Predation was the main cause of the losses (over 50%).
Keywords: breeding biology, nest cards, Sylvia communis, Whitethroat
