Stroke and glide of wing-propelled divers: deep diving seabirds adjust surge frequency to buoyancy change with depth.
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ABSTRACT:
SUBMITTER: Watanuki Y
PROVIDER: S-EPMC1691262 | biostudies-literature | 2003 Mar
REPOSITORIES: biostudies-literature
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Stroke and glide of wing-propelled divers: deep diving seabirds adjust surge frequency to buoyancy change with depth.
Watanuki Yutaka Y Niizuma Yasuaki Y Gabrielsen Geir Wing GW Sato Katsufumi K Naito Yasuhiko Y
Proceedings. Biological sciences 20030301 1514
In order to increase locomotor efficiency, breath-holding divers are expected to adjust their forward thrusts in relation to changes of buoyancy with depth. Wing propulsion during deep diving by Brünnich's guillemots (Uria lomvia) was measured in the wild by high-speed (32 Hz) sampling of surge (tail-to-head) and heave (ventral-to-dorsal) accelerations with bird-borne data loggers. At the start of descent, the birds produced frequent surges (3.2 Hz) during both the upstroke and the downstroke ag ...[more]
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