We measured the effect of wind speed on the metabolic rate of six adul
t sage grouse (Centrocercus urophasianus) with indirect respiration ca
lorimetry at ambient temperatures above, near, and below the lower cri
tical temperature. There was a significant effect (P < 0.05) of temper
ature on metabolic rate at all wind speeds, and a significant effect (
P < 0.05) of wind speed on metabolic rate for temperatures less than o
r equal to 0 degrees C. Wind speed had a more pronounced effect on met
abolism at temperatures below the lower critical temperature for sage
grouse. Metabolic rates measured at wind speeds of greater than or equ
al to 1.5 m/s were significantly higher than those measured at wind sp
eeds < 1.5 m/s. Multiple regression analysis of wind speed (u; m/s) an
d temperature (T-a; degrees C) on metabolism (MR; mL O-2 . g(-1). h(-1
)) yielded the equation MR = 0.0837 (u) - 0.0248 (T-a) + 0.5444. The p
redicted cost of thermoregulation at conditions of -5 degrees C and u
= 1.5 mis was about 1.5 x standard metabolic rate; half the increase w
as due to wind. Measurements of wind speed in sagebrush (Artemisia spp
.) stands indicate that such habitat effectively reduces wind speed to
< 1.5 m/s. Microhabitat value should be recognized in the management
of sagebrush stands.