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USGS · 70004050

Common Grackle breeding on bottomland forest restoration sites

Daniel J. Twedt
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Abstract

Two of 36 forest restoration sites in the Mississippi Alluvial Valley surveyed from 2000-2002 harbored Quiscalus quiscula (Common Grackle). Occupied sites were in less-forested landscapes and had sparser understory vegetation due to flooding. Probability of daily nest survival (0.9077) of 169 Common Grackle nests was influenced by nest-placement, temporal, and landscape effects. Age of nest markedly affected nest survival, which increased from <0.89 during egg laying (age < 6 days) to >0.92 when nestlings were present (age > 18 days). Extrapolating daily nest survival to a 31 -day nest period resulted in 5% nest success, far less then previously estimated for this species in more northern latitudes and likely less than required to sustain populations on these sites.

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BibTeXRIS

Daniel J. Twedt. 2011. Common Grackle breeding on bottomland forest restoration sites. https://doi.org/10.1656/058.010.0101

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