Ambient Temperature and the Daily Energetics of Two Species of Hummingbirds, Calypte anna and Selasphorus rufus

  title={Ambient Temperature and the Daily Energetics of Two Species of Hummingbirds, Calypte anna and Selasphorus rufus},
  author={Carol A. Beuchat and Susan Budd Chaplin and Martin L. Morton},
  journal={Physiological Zoology},
  pages={280 - 295}
Anna (Calypte anna) and rufous (Selasphorus rufus) hummingbirds exhibited regular diurnal changes in body mass, locomotor activity (flight time and frequency), and feeding activity (frequency and consumption) at ambient temperatures (Ta) from 38 to −1 C. Body mass of both species increased gradually throughout the day and amounted to increases of as much as 16.4% in C. anna (7 C) and 10.8% in S. rufus (22 C). These changes in body mass were related to marked decreases in flight expenditure in… 
Seasonal Changes in Body Mass and Use of Torpor in a Migratory Hummingbird
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Short‐term energy regulation in nectar‐feeding birds: the response of Whitebellied Sunbirds (Nectarinia talatala) to a midday fast
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Torpor in three species of Brazilian hummingbirds under semi-natural conditions
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Energetics of hummingbird foraging at low ambient temperature
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Diurnal Variation in Mass, Metabolic Rate, and Respiratory Quotient in Anna's and Costa's Hummingbirds
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Changes in nectar concentration: how quickly do whitebellied sunbirds (Cinnyris talatala) adjust feeding patterns and food intake?
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When Do Hummingbirds Use Torpor in Nature?
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  • Environmental Science
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  • 1994
Body masses of broad-tailed hummingbirds were used to evaluate the "routine" and "emergency-only" hypothesis of torpor in hummingbirds, and Estimated energy equivalents of daily cycles of storage and depletion did not support the routine hypothesis.
Seasonal and diurnal variations in the energetics and foraging activities of the brown honey eater, Lichmera indistincta
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This investigation was supported, in part, by grant G-9238 from the National Science Foundation to Dr. W. R. Dawson, and by funds from the Graduate Student Research Fund, Horace H. Rackham School of Graduate Studies, University of Michigan.
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Time Budget and Foraging Site Preference of the Cinnamon Hummingbird in Costa Rica
The time budget and pattern of inflorescence utilization by the Cinnamon Hummingbird (Amazilia n&a) at a tropical flowering plant during the dry season in Costa Rica is described.
Time and Energy Budgets of Territorial Hummingbirds
From laboratory data of flying and resting metabolism and field data on time budgets of territorial male Eulampis jugularis hummingbirds we were able to estimate caloric energy budgets associated
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Time, Energy, and Territoriality of the Anna Hummingbird (Calypte anna)
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The Migrations of Allen's and Other Hummingbirds
tually migrates southward in numbers in late spring; further, its route soon veers away, geographically and ecologically, from the northward return route used chiefly in winter. Allen's Hummingbird
Temporal patterning of feeding by hummingbirds
Energetics of Hovering Flight in Hummingbirds and in Drosophila
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