Lethal Heat Exchange—Short-Term Thermoregulation in Two Triturus Species During Abrupt Changes in Living Media (Water vs. Air)

As adults, some newts exhibit a multiphasic lifestyle, switching between aquatic and terrestrial habitats. Under laboratory conditions, we provided an experiment to expose newts, which were in their aquatic phase, to air as a surrounding medium. We studied how the body temperature changed when the ambient temperature increased. The thirteen specimens used in the study belonged to two species from the genus Triturus sp.—T. ivanbureschi and T. dobrogicus. For temperature measurements, we used a precise thermometer with a beaded thermocouple and an IR thermal camera. We started the experiment at 17 °C and increased the air temperature by approximately 1 °C every 10 min. The newts were exposed to the air until the first signs of physical exhaustion appeared. An increase of 1 °C in ambient temperature led to an average increase of 0.87 °C in the body temperature of the newts across the four experimental days. The measured body temperature showed a consistent increase during all experimental sessions, but it did not equalize with the environmental temperature. The body temperature in all specimens remained lower by an average of 2.24 (±0.02) °C.