Within-year nest reuse in open-nesting, solitary breeding passerines

Sammendrag

During fieldwork at Lake Sic (46°57’N, 23°54’E), Romania, in the summer of 2003, we observed a strange incident of nest reuse in the Great Reed Warbler Acrocephalus arundinaceus. After first laying a complete clutch of five eggs and then ejecting an experimentally added parasite egg together with two of its own eggs, a new clutch was initiated in the same nest. In Tana (70°16’N, 28°19’E), Norway, in June 2003, we observed a similar incident in the Brambling Fringilla montifringilla. In a nest that was completely depredated when 3-4 eggs had been laid, a new clutch was initiated 8-9 days later. This is as far as we know the first time nest reuse has been documented in Great Reed Warblers and Bramblings.