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


This study is summarised as evidence for the following.

Action Category

Clean nest boxes to increase occupancy or reproductive success

Action Link
Bird Conservation
  1. Clean nest boxes to increase occupancy or reproductive success

    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.


Output references

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