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Adaptive airspeed adjustment and compensation for wind drift in the common swift : differences between day and night

Hedenström, Anders LU and Åkesson, Susanne LU (2017) In Animal Behaviour 127. p.117-123
Abstract

Migratory birds are known to be capable of adjusting their heading direction to compensate for wind drift and their airspeed adaptively with respect to head and tail winds. High-flying nocturnally migrating common swifts, Apus apus, have been shown to compensate for wind drift, but they failed to adjust airspeed as expected (increase in head wind and decrease in tail wind in relation to neutral wind). We report on new measurements of diurnally migrating common swifts at a coastal site in the Baltic, where the birds did adjust airspeed adaptively during spring and autumn migration. During autumn migration, they compensated for lateral wind drift by adjusting heading direction similarly to high-altitude migrants in autumn. We also... (More)

Migratory birds are known to be capable of adjusting their heading direction to compensate for wind drift and their airspeed adaptively with respect to head and tail winds. High-flying nocturnally migrating common swifts, Apus apus, have been shown to compensate for wind drift, but they failed to adjust airspeed as expected (increase in head wind and decrease in tail wind in relation to neutral wind). We report on new measurements of diurnally migrating common swifts at a coastal site in the Baltic, where the birds did adjust airspeed adaptively during spring and autumn migration. During autumn migration, they compensated for lateral wind drift by adjusting heading direction similarly to high-altitude migrants in autumn. We also recorded flight speed and wind compensation during a summer weather-related exodus, when the birds behaved similarly to those during autumn migration, although they showed a small degree of wind drift. Why birds failed to adjust airspeed adaptively at high altitude is discussed, and we argue there is a threshold in the sensory system to detect small changes in optic flow based on visual landmarks.

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Please use this url to cite or link to this publication:
author
organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
airspeed, Apus apus, migration, optic flow, visual constraint, weather movement, wind compensation
in
Animal Behaviour
volume
127
pages
7 pages
publisher
Elsevier Ltd
external identifiers
  • scopus:85017001684
  • wos:000402702900014
ISSN
0003-3472
DOI
10.1016/j.anbehav.2017.03.010
language
English
LU publication?
yes
id
d42825b7-2982-4eed-b88d-7ab4aadb7255
date added to LUP
2017-04-26 11:34:56
date last changed
2018-01-07 12:00:52
@article{d42825b7-2982-4eed-b88d-7ab4aadb7255,
  abstract     = {<p>Migratory birds are known to be capable of adjusting their heading direction to compensate for wind drift and their airspeed adaptively with respect to head and tail winds. High-flying nocturnally migrating common swifts, Apus apus, have been shown to compensate for wind drift, but they failed to adjust airspeed as expected (increase in head wind and decrease in tail wind in relation to neutral wind). We report on new measurements of diurnally migrating common swifts at a coastal site in the Baltic, where the birds did adjust airspeed adaptively during spring and autumn migration. During autumn migration, they compensated for lateral wind drift by adjusting heading direction similarly to high-altitude migrants in autumn. We also recorded flight speed and wind compensation during a summer weather-related exodus, when the birds behaved similarly to those during autumn migration, although they showed a small degree of wind drift. Why birds failed to adjust airspeed adaptively at high altitude is discussed, and we argue there is a threshold in the sensory system to detect small changes in optic flow based on visual landmarks.</p>},
  author       = {Hedenström, Anders and Åkesson, Susanne},
  issn         = {0003-3472},
  keyword      = {airspeed,Apus apus,migration,optic flow,visual constraint,weather movement,wind compensation},
  language     = {eng},
  month        = {05},
  pages        = {117--123},
  publisher    = {Elsevier Ltd},
  series       = {Animal Behaviour},
  title        = {Adaptive airspeed adjustment and compensation for wind drift in the common swift : differences between day and night},
  url          = {http://dx.doi.org/10.1016/j.anbehav.2017.03.010},
  volume       = {127},
  year         = {2017},
}