Taipei, June 19 (CNA) The Taipei Zoo has launched a campaign to hunt down spot-legged tree frogs in the zoo environs to prevent the alien species from threatening the survival of the endemic white-lipped tree frog, a relative of the invasive species.
In a statement released Monday, the city zoo said a "spot-removing" task force has been formed in cooperation with Yang Yi-ju, a frog expert and associate professor at the National Dong Hwa University Graduate Institute of Marine Biodiversity and Evolutionary Biology.
The team is tasked with removing several hundred spot-legged tree frogs and their eggs within the zoo before the end of the year, zoo officials said.
According to the zoo, spot-legged tree frogs were first discovered in Taiwan in 2006, when a Taichung resident found clumps of spawn on water plants he had purchased. He originally thought they were from the white-lipped tree frog but later discovered them to be of a different species.
The frog spread fast, but was not identified as an invasive species until 2010, the zoo said.
Spot-legged tree frogs and Taiwan's endemic white-lipped tree frogs are similar to each other in terms of size, color and camouflage. One thing that differentiates them from one another is their croaks: the white-lipped tree frog's croak sounds like "ta ta ta" while that of the alien species sounds more like "ga ga ga," the zoo officials said.
In addition, the white-black spot patterns on the legs of the two species are also different, they noted.
The zoo said the population of spot-legged tree frogs in the zoo has increased since they were first discovered there in 2010.
The frog, which is found in southern China, the Indochinese peninsula and India, has excellent hiding skills and is an efficient breeder. It lays around 600 eggs at a time, almost double the number produced by its Taiwanese relative, the officials said, warning that the invader could drive the endemic species to extinction if it is left to build further colonies in Taiwan.
(By Elizabeth Hsu)