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Providing evidence to improve practice

Individual study: Effects of removal of old nesting material on nest box occupancy and breeding success of prothonotary warblers Protonotaria citrea at Presquile National Wildlife Refuge, Virginia, USA

Published source details

Blem C.R., Blem L.B. & Berlinghoff L.S. (1999) Old nests in prothonotary warbler nest boxes: effects on reproductive performance. Journal of Field Ornithology, 70, 95-100


This study is summarised as evidence for the intervention(s) shown on the right. The icon shows which synopsis it is relevant to.

Clean nest boxes to increase occupancy or reproductive success Bird Conservation

A replicated, controlled study in a tidal swamp in Virginia, USA (Blem et al. 1999), found that prothonotary warblers Protonotaria citrea showed no preference for cleaned nest boxes compared to control boxes with old nests in (32-38% of 164 cleaned boxes vs. 26-41% of 136 controls). The presence of an old nest did not affect laying date, clutch size, nestling mortality or brood parasitism by brown-headed cowbirds Molothrus ater (first eggs laid on 4th May, average of 5.1 eggs/clutch and 4% parasitism for both cleaned and control boxes; 14% egg and nestling loss for cleaned boxes vs. 10% for controls). Overall, warblers built 207 nests in 300 nest boxes provided.