On penguin porpoising

Speeds above which porpoising becomes energetically more economical than swimming are calculated from a hydro-mechanical model for Humboldt (Spheniscus humboldti) and emperor (Aptenodytes forsteri) penguins. Predicted minimum porpoising speeds for S. humboldti are significantly less than observed va...

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Bibliographic Details
Published in:Canadian Journal of Zoology
Main Authors: Blake, R. W., Smith, M. D.
Format: Article in Journal/Newspaper
Language:English
Published: Canadian Science Publishing 1988
Subjects:
Online Access:http://dx.doi.org/10.1139/z88-310
http://www.nrcresearchpress.com/doi/pdf/10.1139/z88-310
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Summary:Speeds above which porpoising becomes energetically more economical than swimming are calculated from a hydro-mechanical model for Humboldt (Spheniscus humboldti) and emperor (Aptenodytes forsteri) penguins. Predicted minimum porpoising speeds for S. humboldti are significantly less than observed values. At low porpoising speeds time in air is low and may not be sufficient to permit efficient breathing. It is suggested that ventilatory requirements may set a practicable lower bound on porpoising speed. Other possible constraints on the lower limits to porpoising speed include the requirement of raising the centre of mass high enough for the animal to completely clear the surface and the influence of sea conditions.