Artificial ponds can be ecological traps for amphibians: A case study from Chuxiong Prefecture, Yunnan, China

Agricultural activities have been one of the main factors that threaten the survival of wild animals. Artificial ponds constructed in many rural areas may either provide suitable habitats or act as ecological traps for local amphibians due to their dependence on water. Since the late 1990s, many artificial ponds (>230,000) were built in Chuxiong Prefecture, Yunnan, southwest China. It remains unclear to what extent those artificial ponds affect local amphibian populations. To evaluate different factors that could have an impact on the survival of am-phibians in the ponds, particularly on those ground-dwelling species that lack strong climbing capabilities, we conducted field surveys, including using a mark-and-recapture approach, and performing laboratory experi-ments. A total of ten species of amphibians were recorded from 97 artificial ponds. Laboratory result based on the most abundant frog species-Nidirana pleuraden (Ranidae), an agile ground dweller-indicated that they failed to escape when water level to pond surface (WLPS) is at 20 cm or greater. We identified that only <20 % of the surveyed pond maintained the water level safe for N. pleuraden and that up to 70 % of ponds posed high risk, regardless of seasonality (i.e., dry season vs. rainy season). Placing floating objects as simple as a Styrofoam plate or aquatic plants in the ponds can significantly extend survival time of trapped amphibians. More frequent pond -refills also reduce mortality. Our findings can benefit conservation effort in agricultural areas, where amphibians are closely associated with artificial ponds.