A study on the use of ecological fences for protection against Polypedates megacephalus

Abstract

Polypedates megacephalus is a species of frog originating in Southeast Asia and India. In recent years they have entered Taiwan and proliferated as a result of the illegal introduction of economic plants. Due to their enormous reproductive capacity, the species is encroaching on the living spaces of other amphibians, destroying the native ecological balance and posing a threat to the survival of native species. This study investigated the effects of blocking the exotic species P. megacephalus using an ecological fence and presented the fence height and angle adjusting mechanism as a reference for users. In July 2012, this study collected specimens of P. megacephalus in Taiwan Township of Changhua County. The specimens’ body weight, body length, jumping length and jumping height were measured, and then fence height and angle tests were conducted. The experimental results indicated that compared with the male frogs, the female frogs were two to three centimeters longer in body length, three times heavier in body weight and could jump 17cm higher. The average jump height for P. megacephalus at 40cm from the fence was 27±12cm. In the test for setting the fence angle against crossing over, it was found that the frogs could not cling at an angle 65°. Therefore, based on these data, it was possible to determine the height and angle of the ecological fence needed to keep out P. megacephalus. This study provided useful suggestions for the future control of P. megacephalus using ecological preservers.