The Green Bamboo Pit Viper, Trimeresurus stejnegeri, Discriminates Chemical Stimuli Among Anuran Species

Abstract

The green bamboo pit viper, Trimeresurus stejnegeri, is a sit-and-wait predator that forages mainly on frogs in Taiwan. We predicted that T. stejnegeri is able to identify prey at the species level to locate appropriate ambushing sites. We conducted a chemical preference test among frog species and compared its result with the natural diet of T. stejnegeri. The test suggested that T. stejnegeri can discriminate prey species even within the same family. The three highest tongue flick ambush scores (TFAM) were obtained in Odorrana swinhoana, Polypedates braueri, and Zhangixalus moltrechti, which corresponded to the dominant prey items found in stomach contents. Some frog species, however, did not show coincidence between TFAM and the snake's natural diet. Abundance, active period, and defensive mechanisms of frogs are potential factors affecting the realized diet of T. stejnegeri in the field. We also propose that ambushing behavior exhibited during the chemical preference test should be considered an important indicator of interest in potential prey for sit-and-wait species of snakes.