Mammals arousing from hibernation display pronounced regional heterothermy where the thoracic and head regions warm faster than the abdominal and hind-limb regions. We used laser Doppler flowmetry to measure peripheral hind-foot blood flow during hibernation and arousal and gamma imaging of technetium labeled albumin to measure whole blood volume distribution in hamsters arousing from hibernation. It was discovered that the hibernating hamster responds to physical but not sound or hypercapnic stimulation with rapid, 73% reduction of hind foot blood flow (HFBF). HFBF vasoconstriction was maintained from the onset of arousal until late in arousal when rectal temperature is rapidly increased. Alpha-adrenergic blockade early in arousal increased HFBF by 700% suggesting that vasoconstriction was mediated by activation of sympathetic tone. Gamma imaging revealed that by the early phase of arousal from hibernation, the blood volume of the body below the liver is greatly reduced while that of the thorax and head is much greater than in anesthetized hamsters. As arousal progresses and cardiac activity increases and regional heterothermy develops, this regional blood volume distribution is largely maintained however blood volume slowly decreases in the thoracic region and slowly increases in shoulder/head regions. The rapid increase in rectal temperature characteristic of mid-to-late arousal phases is probably mediated, in part, by reduction of adrenergic tone on abdominal and hind limb vasculature. Warm blood then moves into the hind-body, produces an increase in temperature, blood flow and blood volume in the hind-body and compensatory reductions of blood volume in the neck, head and thoracic regions.