Impacts of temperature on growth, development and survival of larval Bufo (Pseudepidalea) viridis (Amphibia: Anura): implications of climate change

摘要

The changing global climate poses a new threat to amphibian populations since amphibian growth and development are strongly influenced by temperature. In general, low temperature reduces their physiological processes, decreasing development and growthrates. However, metamorphs of some amphibian species may be larger than their conspecifics grown at high temperatures. The increased temperature can reduce the metamorphic size in some species, whereas in other species, high temperatures accelerate growth with no changes in body size at metamorphosis. In orderto testthe influence of watertemperatureon larval growth, development and survival of the green toad Bufo viridis, 200 eggs were raised separately at two different water temperatures (18 and 21 °C) for the period of 16 weeks. The results show that the larvae reared at high temperature reached metamorphosis significantly faster (86.58 ± 13.47 days) than those reared at low temperature (105.4 ± 7.83 days). However, the larvae reared at high temperature showed a significant increase in survival rate (64% ± 34.22) compared to the larvae reared at low temperature (23.57% ± 4.18). The growth rate of the larvae reared at higher temperature was higher than that of the larvae reared at low temperature but this difference was not significant. In contrast, the average size at metamorphosis (SVL) at low temperature was significantly larger (19.05 ±1.12 mm) compared with that of the individuals that metamorphosed at the relatively higher temperature (16.11 ±1.54 mm).