The presence of predators constrains larval development process by influencing critical developmental windows in the endangered Chinhai spiny newt

Abstract

Predators significantly impact the development process and subsequently influence the metamorphic decisions of amphibian larvae. Larvae often exhibit induced growth and metamorphic plasticity in response to the presence of predators. However, growth and development rates are not always perfectly correlated, growth responses can vary throughout ontogeny. It is crucial to consider the stage‐specific growth responses induced by predators. Here, we employ a critical windows experimental design and examine development‐related growth and metamorphic responses to predators in the endangered Chinhai spiny newt (Echinotriton chinhaiensis). Our findings reveal that predators constrain the development process of spiny newt larvae and also impact survival to metamorphosis. Inducible plasticity predominantly exhibits in the early and middle stages of larval development. Our results also suggest that diverse developmental plasticity has been adopted by larvae in response to predators. The presence of predators during early stage induces larvae to exhibit a same size at metamorphosis but a prolonged time to metamorphosis, while predators present during middle stage induce larvae to exhibit a large size at metamorphosis but a same time to metamorphosis. The presence of predators at the late developmental stage does not induce any plasticity in larval growth and metamorphosis. Moreover, these results also suggest that several stages of larval development are likely critical developmental windows for spiny newt larvae. This study not only provides basic biological information on predator‐induced developmental plasticity of the endangered Chinhai spiny newt but also likely provides biological insights for the implementation of in situ conservation and preservation efforts for endangered species.