Hovering Energetics and Thermal Balance in Anna’s Hummingbirds (Calypte anna)

  title={Hovering Energetics and Thermal Balance in Anna’s Hummingbirds (Calypte anna)},
  author={Dennis J Evangelista and Mar{\'i}a Jos{\'e} Fern{\'a}ndez and Madalyn S. Berns and Aaron Hoover and Robert Dudley},
  journal={Physiological and Biochemical Zoology},
  pages={406 - 413}
We studied the energetics of hover‐feeding Anna’s hummingbirds, using three different simultaneous techniques: heat loss as estimated via thermal imaging, metabolic rate as measured at a feeder mask using flow‐through respirometry, and aerodynamic power estimated from wingbeat kinematic data. These three methods yielded comparable estimates of power output at ambient air temperatures ranging from 18° to 26°C, whereas heat imbalance at higher air temperatures (up to 34°C) suggested loss by… 
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