Breeding Destinations and Spring Migration Patterns of Swainson's Thrush (Catharus ustulatus) at a Costa Rican Stopover Site
Stable-isotope analysis of feathers has become a useful tool for examining migration patterns and annual connectivity of migratory songbird populations. We used this approach, combined with molecular sex-identification, to examine expected breeding destinations and migration ecology of Swainson'...
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American Ornithological Society
2008
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Online Access: | https://doi.org/10.1525/auk.2008.125.1.95 |
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ftbioone:10.1525/auk.2008.125.1.95 2024-05-12T08:12:27+00:00 Breeding Destinations and Spring Migration Patterns of Swainson's Thrush (Catharus ustulatus) at a Costa Rican Stopover Site Scott Wilson Keith A. Hobson Douglas M. Collister Amy G. Wilson Scott Wilson Keith A. Hobson Douglas M. Collister Amy G. Wilson world 2008-01-01 text/HTML https://doi.org/10.1525/auk.2008.125.1.95 en eng American Ornithological Society doi:10.1525/auk.2008.125.1.95 All rights reserved. https://doi.org/10.1525/auk.2008.125.1.95 Text 2008 ftbioone https://doi.org/10.1525/auk.2008.125.1.95 2024-04-16T02:13:14Z Stable-isotope analysis of feathers has become a useful tool for examining migration patterns and annual connectivity of migratory songbird populations. We used this approach, combined with molecular sex-identification, to examine expected breeding destinations and migration ecology of Swainson's Thrush (Catharus ustulatus) at a spring stopover site on the Osa Peninsula of Costa Rica. The number of individuals passing through the site increased in late March and peaked in mid-April before declining toward late April. Plumage and expected feather-deuterium (δDf) values for North America indicated that most individuals had probably bred or fledged in west-central regions of the boreal forest and western mountains, rather than farther north in the Yukon and Alaska or in eastern regions of Canada and the United States. Average δDf values differed little between males and females, indicating similar breeding destinations, though females tended to show greater variability. The δDf values of second-year and after-second-year birds differed only slightly, which suggests that most adults molted near the breeding grounds. Timing of migration through the site was not related to breeding latitude as inferred from feather δD. We also found little relation between the energetic reserves carried by individuals and their expected breeding destination, possibly because the reserves carried at this stage have little relation to the total reserves needed by northern breeders for the final stage of migration.Destinos de Cría y Patrones de Migración de Primavera de Catharus ustulatus en un Sitio de Escala en Costa Rica Text Alaska Yukon BioOne Online Journals Canada Yukon The Auk 125 1 95 104 |
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Open Polar |
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BioOne Online Journals |
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ftbioone |
language |
English |
description |
Stable-isotope analysis of feathers has become a useful tool for examining migration patterns and annual connectivity of migratory songbird populations. We used this approach, combined with molecular sex-identification, to examine expected breeding destinations and migration ecology of Swainson's Thrush (Catharus ustulatus) at a spring stopover site on the Osa Peninsula of Costa Rica. The number of individuals passing through the site increased in late March and peaked in mid-April before declining toward late April. Plumage and expected feather-deuterium (δDf) values for North America indicated that most individuals had probably bred or fledged in west-central regions of the boreal forest and western mountains, rather than farther north in the Yukon and Alaska or in eastern regions of Canada and the United States. Average δDf values differed little between males and females, indicating similar breeding destinations, though females tended to show greater variability. The δDf values of second-year and after-second-year birds differed only slightly, which suggests that most adults molted near the breeding grounds. Timing of migration through the site was not related to breeding latitude as inferred from feather δD. We also found little relation between the energetic reserves carried by individuals and their expected breeding destination, possibly because the reserves carried at this stage have little relation to the total reserves needed by northern breeders for the final stage of migration.Destinos de Cría y Patrones de Migración de Primavera de Catharus ustulatus en un Sitio de Escala en Costa Rica |
author2 |
Scott Wilson Keith A. Hobson Douglas M. Collister Amy G. Wilson |
format |
Text |
author |
Scott Wilson Keith A. Hobson Douglas M. Collister Amy G. Wilson |
spellingShingle |
Scott Wilson Keith A. Hobson Douglas M. Collister Amy G. Wilson Breeding Destinations and Spring Migration Patterns of Swainson's Thrush (Catharus ustulatus) at a Costa Rican Stopover Site |
author_facet |
Scott Wilson Keith A. Hobson Douglas M. Collister Amy G. Wilson |
author_sort |
Scott Wilson |
title |
Breeding Destinations and Spring Migration Patterns of Swainson's Thrush (Catharus ustulatus) at a Costa Rican Stopover Site |
title_short |
Breeding Destinations and Spring Migration Patterns of Swainson's Thrush (Catharus ustulatus) at a Costa Rican Stopover Site |
title_full |
Breeding Destinations and Spring Migration Patterns of Swainson's Thrush (Catharus ustulatus) at a Costa Rican Stopover Site |
title_fullStr |
Breeding Destinations and Spring Migration Patterns of Swainson's Thrush (Catharus ustulatus) at a Costa Rican Stopover Site |
title_full_unstemmed |
Breeding Destinations and Spring Migration Patterns of Swainson's Thrush (Catharus ustulatus) at a Costa Rican Stopover Site |
title_sort |
breeding destinations and spring migration patterns of swainson's thrush (catharus ustulatus) at a costa rican stopover site |
publisher |
American Ornithological Society |
publishDate |
2008 |
url |
https://doi.org/10.1525/auk.2008.125.1.95 |
op_coverage |
world |
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Canada Yukon |
geographic_facet |
Canada Yukon |
genre |
Alaska Yukon |
genre_facet |
Alaska Yukon |
op_source |
https://doi.org/10.1525/auk.2008.125.1.95 |
op_relation |
doi:10.1525/auk.2008.125.1.95 |
op_rights |
All rights reserved. |
op_doi |
https://doi.org/10.1525/auk.2008.125.1.95 |
container_title |
The Auk |
container_volume |
125 |
container_issue |
1 |
container_start_page |
95 |
op_container_end_page |
104 |
_version_ |
1798834804274233344 |