Patterns of respiration in diving penguins: Is the last gasp an inspired tactic?
Date
2003
Authors
Wilson R.P.
Simeone A.
Luna-Jorquera G.
Steinfurth A.
Jackson S.
Fahlman A.
Journal Title
Journal ISSN
Volume Title
Publisher
Abstract
Humboldt penguins Spheniscus humboldti in captivity and free-living Magellanic penguins S. magellanicus were fitted with loggers to determine beak angles during breathing. The Humboldt penguins were also fitted with masks for determining rates of air flow during breathing. During periods of higher gas exchange requirement, Humboldt penguins opened their beaks during inspiration, where tidal volume was linearly correlated with both change in beak angle and maximum beak angle, closed them slightly during the final stages of inspiration and finally closed them during expiration. Substantial differences were apparent between individuals. Contrary to the condition proposed for most birds, our data suggest that expiration is passive during periods of high respiratory tidal volumes, and that the increased resistance of the respiratory pathway serves to slow air flow so as to maximize gas exchange in the lungs. During foraging, Magellanic penguins at the surface between dives showed similar breathing patterns but maximum beak angles were much higher and breath cycle time shorter, as would be expected for animals attempting to maximize gas exchange. Both maximum beak angle per breath and breath frequency changed systematically over the surface pause; both were initially high, then decreased to a low before rising again to a maximum just before diving. Based on known changes in tidal volume with beak angle derived from Humboldt penguins, a simple model is proposed to examine rates of gas exchange over the surface pause. This indicates that the observed patterns do not maximize the rate of transfer of oxygen over the whole of the surface pause but are rather concerned with an initial rapid accumulation of oxygen in the tissues followed by effective carbon dioxide release.
Description
Keywords
animal, article, biological model, bird, breathing mechanics, diving, lung gas exchange, physiology, respiratory function, tidal volume, Animals, Birds, Diving, Models, Biological, Pulmonary Gas Exchange, Respiratory Mechanics, Respiratory Physiology, Tidal Volume, Animalia, Aves, Spheniscidae, Spheniscus, Spheniscus humboldti, Spheniscus magellanicus
Citation
Journal of Experimental Biology
206
10
206
10