Contrasts in Energy Status and Marine Foraging Strategies of White-Winged Scoters (Melanitta fusca) and Surf Scoters (M. Perspicillata)
White-winged Scoters (Melanitta fusca) and Surf Scoters (M. perspicillata) are often assumed to rely on similar marine resources. To evaluate the accuracy of this assumption, we contrast seasonal distributions, foraging effort, and indicators of energy status (body mass and composition, plasma metab...
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ftbioone:10.1525/auk.2011.10088 2024-05-12T08:06:52+00:00 Contrasts in Energy Status and Marine Foraging Strategies of White-Winged Scoters (Melanitta fusca) and Surf Scoters (M. Perspicillata) Eric M. Anderson James R. Lovvorn Eric M. Anderson James R. Lovvorn world 2011-04-01 text/HTML https://doi.org/10.1525/auk.2011.10088 en eng American Ornithological Society doi:10.1525/auk.2011.10088 All rights reserved. https://doi.org/10.1525/auk.2011.10088 Text 2011 ftbioone https://doi.org/10.1525/auk.2011.10088 2024-04-16T02:13:14Z White-winged Scoters (Melanitta fusca) and Surf Scoters (M. perspicillata) are often assumed to rely on similar marine resources. To evaluate the accuracy of this assumption, we contrast seasonal distributions, foraging effort, and indicators of energy status (body mass and composition, plasma metabolites) in three major foraging sites in Puget Sound, Washington, for these rapidly declining sea duck congeners. For Surf Scoters, distributions and energy status indicated that a mussel-dominated site was relatively important in early winter, but that importance shifted during late winter and spring to seagrass sites that provided either herring spawn or epifaunal invertebrates. As winter progressed, movements among foraging sites and increased foraging effort by Surf Scoters were accompanied by greater variability in their energy status compared with White-winged Scoters; body mass declined over winter by >9% in about one-third of past studies for Surf Scoters, well above the range of losses observed in White-winged Scoters. For White-winged Scoters, lower variability in energy status, foraging effort, and distributions throughout winter suggests that they are better able to regulate energy balance regardless of changing foraging conditions. Greater resistance to seasonal environmental changes in White-winged Scoters may be related to their >50% larger body size, which confers lower mass-specific energy costs and access to a wider size range of bivalve prey. Perhaps because of their greater sensitivity to winter foraging conditions, Surf Scoters appear to rely on a broader range of foraging sites than White-winged Scoters. Text Melanitta fusca BioOne Online Journals The Auk 128 2 248 257 |
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BioOne Online Journals |
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ftbioone |
language |
English |
description |
White-winged Scoters (Melanitta fusca) and Surf Scoters (M. perspicillata) are often assumed to rely on similar marine resources. To evaluate the accuracy of this assumption, we contrast seasonal distributions, foraging effort, and indicators of energy status (body mass and composition, plasma metabolites) in three major foraging sites in Puget Sound, Washington, for these rapidly declining sea duck congeners. For Surf Scoters, distributions and energy status indicated that a mussel-dominated site was relatively important in early winter, but that importance shifted during late winter and spring to seagrass sites that provided either herring spawn or epifaunal invertebrates. As winter progressed, movements among foraging sites and increased foraging effort by Surf Scoters were accompanied by greater variability in their energy status compared with White-winged Scoters; body mass declined over winter by >9% in about one-third of past studies for Surf Scoters, well above the range of losses observed in White-winged Scoters. For White-winged Scoters, lower variability in energy status, foraging effort, and distributions throughout winter suggests that they are better able to regulate energy balance regardless of changing foraging conditions. Greater resistance to seasonal environmental changes in White-winged Scoters may be related to their >50% larger body size, which confers lower mass-specific energy costs and access to a wider size range of bivalve prey. Perhaps because of their greater sensitivity to winter foraging conditions, Surf Scoters appear to rely on a broader range of foraging sites than White-winged Scoters. |
author2 |
Eric M. Anderson James R. Lovvorn |
format |
Text |
author |
Eric M. Anderson James R. Lovvorn |
spellingShingle |
Eric M. Anderson James R. Lovvorn Contrasts in Energy Status and Marine Foraging Strategies of White-Winged Scoters (Melanitta fusca) and Surf Scoters (M. Perspicillata) |
author_facet |
Eric M. Anderson James R. Lovvorn |
author_sort |
Eric M. Anderson |
title |
Contrasts in Energy Status and Marine Foraging Strategies of White-Winged Scoters (Melanitta fusca) and Surf Scoters (M. Perspicillata) |
title_short |
Contrasts in Energy Status and Marine Foraging Strategies of White-Winged Scoters (Melanitta fusca) and Surf Scoters (M. Perspicillata) |
title_full |
Contrasts in Energy Status and Marine Foraging Strategies of White-Winged Scoters (Melanitta fusca) and Surf Scoters (M. Perspicillata) |
title_fullStr |
Contrasts in Energy Status and Marine Foraging Strategies of White-Winged Scoters (Melanitta fusca) and Surf Scoters (M. Perspicillata) |
title_full_unstemmed |
Contrasts in Energy Status and Marine Foraging Strategies of White-Winged Scoters (Melanitta fusca) and Surf Scoters (M. Perspicillata) |
title_sort |
contrasts in energy status and marine foraging strategies of white-winged scoters (melanitta fusca) and surf scoters (m. perspicillata) |
publisher |
American Ornithological Society |
publishDate |
2011 |
url |
https://doi.org/10.1525/auk.2011.10088 |
op_coverage |
world |
genre |
Melanitta fusca |
genre_facet |
Melanitta fusca |
op_source |
https://doi.org/10.1525/auk.2011.10088 |
op_relation |
doi:10.1525/auk.2011.10088 |
op_rights |
All rights reserved. |
op_doi |
https://doi.org/10.1525/auk.2011.10088 |
container_title |
The Auk |
container_volume |
128 |
container_issue |
2 |
container_start_page |
248 |
op_container_end_page |
257 |
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1798849390894383104 |