Metabolic Calculators: Birds (Interspecific)
Here are some metabolic calculators for birds, which predict metabolic rates on the basis of body mass. These are interspecific allometries, and are valid only for basal metabolic rates (the animal is post-absorptive, inactive and within its thermal neutral zone). Typical metabolic rates may be somewhat higher. Energy equivalents (Watts, Joules) assume an RQ of 0.83. Like all allometrically-based estimates of metabolic rates, the results are approximate, but should be close enough to real values to act as a reality check.
Flow rate suggestions are for typical flow-through respirometry and are also approximate. The highest usable flow rate is dependent on the quality of the O2 analyzer being used, which determines the lowest change in O2 concentration that can be reliably resolved. Examples of "superb" and "good" O2 analyzers can be found here and here, respectively. In general, a good flow rate to aim for is about 50% of the suggested maximum for the grade of analyzer you are using. The minimum flow rate corresponds to a 1.5% depletion of O2 in the excurrent air and should be exceeded by at least twofold if at all possible.
Note that all metabolic calculator JavaScript code on this page is (c) John Lighton 2008. All rights are reserved. You are welcome to link to this page without restrictions, but copying and re-posting of the code is strictly prohibited. Suggestions for additional taxa and citations are welcome.