Torpor in an Andean Hummingbird: Its Ecological Significance

@article{Carpenter1974TorporIA,
  title={Torpor in an Andean Hummingbird: Its Ecological Significance},
  author={F. Lynn Carpenter},
  journal={Science},
  year={1974},
  volume={183},
  pages={545 - 547}
}
  • F. Carpenter
  • Published 8 February 1974
  • Environmental Science
  • Science
Field studies on an Andean hummingbird showed that nocturnal torpor occurs more frequently and lasts longer in the winter. Energy depletion does not seem to cause this yearly torpor cycle, and a photoperiodically controlled rhythm that enables the birds to automatically conserve energy in early evening for possible metabolic expenditures required later in the winter night is suggested. 

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Comparison of whether patterns of torpor of several mammals and birds differ between the laboratory and field suggests that laboratory studies are likely to underestimate use and depth oftorpor in the wild and thus may underestimate its impact on energy expenditure and survival.

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References

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The West Indian hummingbird, Eulampis jugularis, maintained its body temperature in torpor at 18� to 20�C over an ambient temperature range of 2.5� to 18�C. At ambient below 18�C oxygen consumption

Environmental influence of regulated body temperature in torpid hummingbirds.

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  • Environmental Science
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  • 1972

Hypothermia of Broad-Tailed Hummingbirds during Incubation in Nature with Ecological Correlations

The first continuous recordings of natural hypothermia, and the only evidences of hypothermia during incubation, were obtained from temperature sensors embedded in synthetic hummingbird eggs placed

Temperature Relationships and Nesting of the Calliope Hummingbird

This is a consequence of the inverse relationship of surface/volume ratio to body mass (Mo.67/M1.? = M-0.33) and of thermal conductance to body mass (M-0.5; Herreid and Kessel 1967; Lasiewski et al.

Use of Caves by Hummingbirds and Other Species at High Altitudes in Peru

Most hummingbirds live in the tropics. Those living in cold climates are faced with the problem of supporting their exceedingly high rate of metabolism over long periods of darkness and bad weather.

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TLDR
The measured time course of body temperature and oxygen consumption during entry into torpor compare favorably with theoretical curves calculated under conditions of minimum heat production and maximum heat loss, and further investigations of the effects of body size on heatproduction and loss are suggested.

Similar to those used for the monkey by

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  • 1972

Pearson for guidance in this project: The Museum of Vertebrate Zoology and a Chapman grant from the American Museum of Natural History provided funding, equipment, and space