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Exploring overlap of feather molting and migration in Tundra Swans using δ2H analysis

Nathan Wolf·T. Scott Smeltz·Jeffrey Welker·Matthew Rogers·Craig R. Ely
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Abstract

Determining the processes that shape the relative timing of energetically-costly events in the annual cycle of migrating birds is important to our understanding of avian phenology and ecology. We paired satellite tracking and hydrogen stable isotope analysis (δ 2 H) to examine the relative timing of two such events – migration and feather molting – in tundra swans from four breeding areas in Alaska, USA. Our results show a trend of increasing intra-individual variability in breast feather δ 2 H values with increasing migration distance, suggesting the overlap of breast feather molting and migration. However, when individual samples were pooled by breeding area, the δ 2 H values of breast and head feathers showed no trend with migration distance, presumably resulting from high levels of inter-individual variability in δ 2 H values within each breeding area. We explore potential reasons for this variability, propose potential mechanisms influencing feather δ 2 H values of tundra swans, and recommend further research into methods for exploring the temporal configuration of events in the annual cycle of migrating birds.

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90° N90° S · 180° W ← longitude → 180° E
Source-reported bounding extent: 50.98609893339354° to 71.45515260247822° latitude; -178.9453125° to -129.97169494628906° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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BibTeXRIS

Nathan Wolf, T. Scott Smeltz, Jeffrey Welker, Matthew Rogers, Craig R. Ely. 2020. Exploring overlap of feather molting and migration in Tundra Swans using δ2H analysis. https://doi.org/10.1515/ami-2020-0102

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