EFFECT OF WINTER TEMPERATURE ON WILD TURKEY METABOLISM

We used indirect calorimetry to measure the effects of air temperature (T-a), age class, and body mass on metabolic rates of 9 adult and 7 j uvenile female eastern wild turkeys (Meleagris gallopavo silvestris) d uring winter. Previous studies produced disparate results on this impo rtant aspect of winter ecology of wild turkeys. Standard metabolic rat es (SMRs) of adult and juvenile hens were not different (P = 0.122) an d averaged 28.69 mL O-2.min(-1).bird(-1). Wild turkey metabolism incre ased with decreasing T-a (P < 0.001) below the lower critical temperat ure (T-lc) of 10.9 degrees C. Metabolic rates were not related to body mass (P = 0.571), and age-specific metabolic rates were not distingui shable (P = 0.998). We estimated that a hock of 20 hens would need to find 400 g/day of additional food to meet thermoregulatory demands for each 10 degrees C drop in T-a below 10.9 degrees C.