Wesołowski T., Czuchra M. 2000. Ekologia rozrodu raniuszka Aegithalos caudatus - analiza polskich kart gniazdowych. (Breeding ecology of the Long-tailed Tit Aegithalos caudatus - an analysis of Polish nest cards). Notatki Ornitologiczne 41: 103-113.

Nest cards collected by the Polish Nest Record Scheme (N=197), mainly in 1981-1990, in S and SW Poland were analysed.The majority of nests were found in woodlands, about 1/3 of them in wet (riverine and alder) woods. They were built in at least 30 different plant species, over half of them in deciduous trees and shrubs, 34% in conifers, and 13% in creepers. The nests were placed next to the main tree trunk (mostly in deciduous species), in forks of branches or among twigs (mostly in conifers). They were situated 0.1-35 m above the ground, much higher in the primaeval forest of the Białowieża National Park (mean - 24 m) than elsewhere in Poland, where 2/3 of nests were at the height of 2 m or lower. Eleven cases of nest building in March (once even in mid-February) were recorded. The earliest clutches were commenced on March 28, the peak of clutch initiation occurred in the first half of April, the latest clutches were laid in the second half of May. Timing of breeding varied significantly among years. Clutches most frequently contained 8-12, on average 10 eggs. Clutch size declined over a season.The total nest loss rate amounted to 75%. Clutches were more frequently destroyed than broods (73 vs 35%). Early nests (initiated before mid-April), and nests in conifers were slightly, though not significantly, more successful. Partial nest loss amounted to less than one egg on average. At least 74% of nest loss was due to predation. At five nests participation of additional birds (helpers) in feeding young was recorded.