Janusz Stępniewski
Ornis Polonica 2012, 53: 233–248
https://doi.org/10.12657/ornis.2012.4.0
Abstract: The study of breeding biology of the Bearded Reedling Panurus biarmicus was carried out at the Łoniewskie Lake in Great Poland in 1987–2009. Nest were placed mostly in sedges Carex sp. (36%; N=131), Narrowleaf Cattail Typha angustifolia (35%; N=126) and reeds Phragmites communis (27%; N=97). Each nest had three-layer structure. Nests were built at the average height of 19.5 cm above the ground (SD=16.19; range 0–83 cm; N=211), and this value increased throughout the season. The earliest first-egg laying date was 17 March, peak of laying occurred in mid April (16% of clutches). Breeding season lasted for 104–152 days, on average 121 days. The average clutch size was 5,6 (SD=1.1; range 2–9 eggs; N=255), and most nests contained 6 (37%) or 5 eggs (29%). Clutch size declined over the season. Nest lossed constituted 45%, and were higher at the nestling (28%) than the egg stage (14%). The most important reasons for nest losses was predation (69% of nests) and adverse weather (12%). The average number of fledglings leaving a nest that had survived until hatching was 3.2 (SD=2.4; N=126).
