Ursidae

Typical thermographic images of adult Malayan sun bears taken shortly after rest and in a postabsorptive state at (A) TA = 23 °C, (B) TA = 28 °C, and (C) TA = 29 °C.
Thermoregulation in Malayan sun bears is not fully understood. Therefore, in this study the effect of meteorological variables on both behavioural and autonomic thermoregulatory mechanisms in sun bears was examined in order to identify temperature thresholds for the activation of various thermoregulatory mechanisms. Infrared thermography was used to non‒invasively determine body surface temperature (TS) distribution in relation to ambient temperature (TA) and to determine the thermoneutral zone (TNZ) of sun bears.