Effects of simulating warming and heat waves on behaviour and survival after reproductive in Rana dybowskii

Abstract

Background Climate change will likely increase the spatial and temporal variability of thermal conditions, particularly the severity and frequency of heat waves. The key factor in forecasting which species will be vulnerable to this threat to biodiversity will be their behavioural responses to climate change. However, few studies have examined how the rate of heat waves and warming affect frog behaviour and survival. This study examined how different rates of constant temperature (5°C, humidity 65 and 85) and temperature increases (approach (A)-naturalistic temperature increase; approach (B)-simulated heat waves from 5°C to 15, 19, or 23°C; and approach (C)-simulated warming from 5°C to 23°C at 0.8, 1.3, or 1.8°C/d) affected frog survival and post reproductive fasting. Result Under (A), Rana dybowskii fasted for 42 days (d), and the survival rate was 27.78 ± 5.09%. In the 15°C group under (B), frog survival decreased to 16.67 ± 5.77%, and feeding began after only 11.00 ± 1.09 d; however, in the other (B) groups, 100% of the frogs died before feeding. Under (C), survival reached 50.00 ± 5.77%, 55.56 ± 1.92% and 41.11 ± 5.09% at temperature rate increases of 0.8, 1.3 and 1.8°C/d, respectively, with significant differences between all pairs of groups. Furthermore, in the 0.8, 1.3 and 1.8°C/d groups, frogs began feeding at 16.87 ± 2.42, 15.46 ± 2.31, and 13.73 ± 1.88 d, respectively, with significant differences between all pairs of groups. In the 5°C (humidity 65.38%) group, the survivorship rate was 81.11 1.57%, while in the 5°C (humidity 85.90%) group, it was 83.33 2.72%. Approaches (A), (B), and (C) differed in survival and postbreeding fasting duration. Conclusions The survival of frogs under simulated heat wave conditions was significantly lower, while fasting time was significantly reduced. Frogs under simulated warming conditions had a higher survival rate and spent less time.