Winter diet of Bobolink, a long-distance migratory grassland bird, inferred from feather isotopes

The condor

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关键词: Bobolink;    diet;    Dolichonyx oryzivorus;    mixing model;    Oryza sativa;    prealternate molt;    rice;    stable carbon isotope;    wintering ecology;   

DOI  :  10.1650/CONDOR-16-162.1

学科分类：动物科学

来源: Central Ornithology Publication Office

【 摘 要 】

ABSTRACT Effective conservation of migratory bird populations depends on advancements in our understanding of processes throughout the life cycle. Fundamental information about wintering ecology (e.g., habitat use and diet composition) remains limited, which limits assessment of threats to populations during winter. Bobolink (Dolichonyx oryzivorus) is a year-round grassland obligate and Nearctic-Neotropical migrant that undergoes 2 complete molts each year, including a complete prealternate molt on the South American wintering grounds. This unusual winter molt provides a rare opportunity to examine, using stable isotope analysis, the timing and contribution of foraging resources in the Bobolink diet prior to northbound migration from disparate breeding populations. We compared winter diet composition among 3 breeding populations of Bobolinks and during 3 stages of winter molt using stable carbon isotope ratios. We used mixing models to compare the ratio of carbon-12 to carbon-13 isotope (δ13C value) in fe...

【 授权许可】

CC BY