LAUSR

The thermal acclimatory capacity of a particular species determines its tolerance to environmental changes and affects its survival under future changing climatic conditions. Acclimation effects on physiological traits have been determined in many fish and frog species, but rarely in newts or salamanders. In the present study, we evaluated the physiological acclimatory response of newts. A total of 48 juvenile Chinese fire⁃belly newts ( Cynops orientalis) were collected and acclimated to 15°C, 20°C, and 25°C, which represented the low, intermediate, and high environmental temperatures experienced by C. orientalis during their active period, respectively, over the course of 4 weeks. The locomotor (swimming) performances of individuals were measured at the same three test temperatures in a glass tank (150 cm × 10 cm × 15 cm) filled with water to a depth of 5 cm, and the critical thermal minimum (CTMin) and maximum (CTMax) were determined using a dynamic method. The thermal resistance range (TRR) was calculated as the difference between CTMax and CTMin, and acclimation response ratio (ARR) of CTMin and CTMax was obtained by dividing the tolerance change by the change in acclimation temperature. The results from repeated⁃measures ANOVA analyses revealed that newt swimming speeds were significantly affected by the acclimation and test temperatures. Despite no statistically significant difference, low and intermediate temperature⁃acclimated newts had relatively high mean swimming speeds at 15°C and 20°C, respectively,