Demographic rates of two southeastern populations of Painted Bunting, 2007–2015

Liani M. Yirka; Jaime A. Collazo; Brian J. O’Shea; J.A. Gerwin; James A. Rotenberg; David T. Cobb

doi:10.1650/condor-17-74.1

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Demographic rates of two southeastern populations of Painted Bunting, 2007–2015

Liani M. Yirka·Jaime A. Collazo·Brian J. O’Shea·J.A. Gerwin·James A. Rotenberg·David T. Cobb

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Abstract

Painted Buntings ( Passerina ciris ) have been declining in the southeastern United States since the 1970s. A recent demographic assessment highlighted the importance of estimating demographic parameters, which have received little attention to date. The dearth of information is troublesome because attempts to reverse declining trends require a better understanding of the relationship between habitat quality and age- and sex-specific survival and recruitment rates. We used capture–mark–recapture data collected from 2007 to 2015 on Bald Head Island (BHI) and at Hammocks Beach State Park (HBSP) in North Carolina, USA, to estimate local age- and sex-specific annual survival rates and local population size and recruitment rates using programs MARK and LOLASURVIV. Juveniles had lower local survival rates than adults (HBSP: 0.28 ± 0.14 vs. 0.67 ± 0.06; BHI: 0.28 ± 0.04 vs. 0.57 ± 0.02). Local annual survival rates for males on BHI (0.50 ± 0.03) were lower than those for females (0.57 ± 0.02). Age-specific differences were consistent with known differential age-dependent survival skills, and sex-specific differences were consistent with the potential influence of sexual dichromism. Conservative estimates of population size on BHI averaged 101 juveniles and 263 adults annually. Annual in situ reproductive recruitment averaged 28 individuals plus an additional 120 new immigrants, indicating successful reproduction and connectivity with neighboring coastal populations. Local adult survival estimates from our 2 North Carolinian study populations were similar to high-end estimates from across the eastern and western range of the species (∼0.60). Finite observed population growth rate estimates between the BHI population (λ = 1.10) and a South Carolinian population (λ = 0.87) underscore the potential role of differential habitat quality and the importance of information from multiple sites, including nonbreeding grounds, for proper inferences about the status of the species. Reported vital rates provide a stronger foundation on which to base habitat quality as assessed with demographic parameters and to guide Painted Bunting conservation regionally.

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Source-reported bounding extent: 33.792843773631844° to 34.95574425733423° latitude; -78.5577392578125° to -76.17919921875° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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Liani M. Yirka, Jaime A. Collazo, Brian J. O’Shea, J.A. Gerwin, James A. Rotenberg, David T. Cobb. 2018. Demographic rates of two southeastern populations of Painted Bunting, 2007–2015. https://doi.org/10.1650/condor-17-74.1

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