(1) We designed a physical model that simulates the thermal and evaporative properties of live Western toads (Bufo boreas).
(2) In controlled tests, the model tracked the body temperature of live toads with an average error of 0.3±0.03 °C (test range=4–30 °C).
(3) It estimated the evaporative water loss of live toads with an average error of 0.35–0.65 g/h, or about 14% (test range=0.7–9 g/h).
(4) Data collected with this physical model should provide an effective way for biologists to better understand habitat selection in toads and other amphibians.