Title
Small energy benefits of in-wake flying in long-duration migratory flights
Language
English
Description (en)
During long-distance migrations, some bird species make use of in-wake flying, which should allow them to profit from the upwash produced by another bird. While indirect evidence supports energy saving as the primary benefit of in-wake flying, measurements are still missing. We equipped migrating northern bald ibises (Geronticus eremita) with high-precision global navigation satellite system data loggers to track their position in the flock. We estimated birds' energy expenditure through different proxies, namely dynamic body acceleration (DBA), heart rate and effective wingbeat frequency. During active flapping flight, DBA estimates dropped off when in-wake compared with when not-in-wake. In addition, effective wingbeat frequency decreased, suggesting an increased use of intermittent gliding flight during in-wake periods. Heart rate varied greatly among individuals, with a clear decrease during gliding-corroborating its energy-saving function. Furthermore, we found consistent proof for decreased heart rate during in-wake flying, by up to 4.2%. Hence, we have shown that flying in the wake of another individual reduces birds' DBA, heart rate and effective wingbeat frequency, which could reflect reduced energy requirement.
Keywords (en)
Animals; Flight; Animal Migration; Energy Metabolism; Birds; Heart Rate; Wings; Acceleration
DOI
10.1098/rspb.2024.1173
Author of the digital object
Elisa  Perinot  (University of Veterinary Medicine Vienna / Waldrappteam)
Bernhard  Voelkl  (Waldrappteam / University of Bern)
Leonida  Fusani  (University of Veterinary Medicine Vienna / University of Vienna)
Thomas  Ruf  (University of Veterinary Medicine Vienna)
Alexei  Vyssotski  (ETH Zurich)
Marco Salvatore  Nobile  (Ca' Foscari University of Venice / University of Milano-Bicocca)
Ortal Mizrahy  Rewald  (University of Veterinary Medicine Vienna / Waldrappteam)
Johannes  Fritz  (University of Vienna / Waldrappteam)
Format
application/pdf
Size
1.0 MB
Licence Selected
CC BY 4.0 International
Type of publication
Article
Name of Publication (en)
Proceedings of the Royal Society B - Biological Science
Pages or Volume
10
Volume
291
Number
2030
Publisher
The Royal Society
Publication Date
2024
Content
Details
Object type
PDFDocument
Format
application/pdf
Created
29.10.2024 09:15:21
This object is in collection
Metadata
University of Veterinary Medicine Vienna (Vetmeduni Vienna) | Veterinärplatz 1 | A-1210 Vienna | Austria | T +43 1 25077-0