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Individual study: Supplementary feeding increases nest attentiveness in female Bewick’s wrens Thryomanes bewickii and house wrens Troglodytes aedon, but not hatching success, at a prairie site in Kansas, USA

Published source details

Pearse A.T., Cavitt J.F. & Cully J.F. (2004) Effects of Food Supplementation on Female Nest Attentiveness and Incubation Mate Feeding in Two Sympatric Wren Species. The Wilson Bulletin, 116, 23-30


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Provide supplementary food for songbirds to increase reproductive success Bird Conservation

A randomised, replicated and controlled trial at a prairie site in Kansas, USA, in April-August 1997 (Pearse et al. 2004) found that female Bewick’s wrens Thyromanes bewickii and house wrens Troglodytes aedon from nest boxes provided with supplementary food spent longer incubating than females from control (unfed) nest boxes (Bewick’s wrens: average incubation bout of 52 min and 82% of time spent on the nest for seven fed females vs. 35 min and 70% for eight controls ; house wrens: averages of 30 min and 81% for nine fed females vs. 13 min and 71% for eight controls). There were no differences in date of clutch initiation, clutch size, the average length of time spent away from the nest or hatching success between treatments (Bewick’s wrens: average bout away from the nest of 10 min for seven fed females, hatching success of 78% vs. 13 min and 74% for eight controls; house wrens: average of 5 min and 96% for nine fed females vs. 5 min and 82% for eight controls). Supplementary food consisted of 15 g of mealworm Tenebrio molitor larvae supplied inside nest boxes every day during incubation, equivalent to almost twice a female wren’s daily energetic requirements.