Experts say May and June are hatching periods, the most appropriate time to catch larvae and juveniles.
Taiwan has announced it will cull up to 120,000 green iguanas with local governments asking the public to help identify iguana nests, recommending fishing spears as the most humane means of killing the animals.
Taiwan’s Forestry and Nature Conservation Agency said that about 200,000 of the reptiles are believed to be in the island’s southern and central areas, which are heavily dependent on farming.
Specially recruited hunting teams killed about 70,000 iguanas last year, with bounties of up to $15 each.
“A lot of people bought them as cute little pets, not realising how big and long-lived they would become, so they set them free in the wild, where they’ve really taken to the Taiwanese environment,” said Lee Chi-ya of the agricultural department in the southern county of Pingtung.
“That’s allowed them to reproduce at a considerable rate, necessitating us to cull them and restore the balance of nature.”
Green iguanas have no natural predators in Taiwan and have moved into areas that can be difficult to access, mostly forests and the edges of towns.
Males can grow to two metres (6.6 feet) long, weigh 5kg (11 pounds) and live up to 20 years, while females can lay up to 80 eggs at a time.
Mainly native to Central America and the Caribbean, they are not aggressive despite possessing sharp tails and jaws and razor-like teeth. The reptiles subsist on a diet of mostly fruit, leaves and plants, with the occasional small animal thrown in.
Though popular as pets, they are difficult to keep healthy in captivity and many die within a year.
Taiwan News website quoted Tainan Agriculture Bureau official Chu Chien-ming as saying that May and June are the hatching periods of green iguanas, making it the most appropriate time to catch larvae and juveniles to prevent their spread and reproduction.