In central and southern Taiwan, green iguanas have become such a problem that officials are offering rewards for locals to kill them. In our Sunday special report, we put the spotlight on a non-native species that was first introduced as an exotic pet, and has since become a nuisance with a cash bounty over its head.

This town where adzuki beans are grown is Pingtung County’s Wandan Township. We are joined by National Pingtung University of Science and Technology researcher, associate professor Chen Tien-hsi, who has brought us here to look in the irrigation channels.

Chen tells us to keep our eyes sharp and to be light on our feet.

Seemingly agitated by our footsteps, we notice iguanas that appear to be alert to our presence. In a flash, one of them disappears through a hole in a stone wall. With the others still appearing agitated, Chen slows down his pace, and approaches quietly. Moments later only one iguana is remaining on the wall, and it looks ready to run off.

After it is caught, the last remaining iguana stares sharply at its surroundings. It looks ready to attack, as if simply waiting for the right opportunity.

Chen Tien-hsi
National Pingtung University of Science and Technology
Mostly when there is a change in the temperature – especially in the winter, early in the morning, before the sun comes up – they will wait for the temperature to warm up before they will come out.

When their nest has been disturbed, iguanas will be on high alert. We decide to move on, and continue our hunt elsewhere.

Chen Tien-hsi
National Pingtung University of Science and Technology
Its belly is bulging. Inside it’s filled with eggs – they will be laid soon. In the south, roughly from the end of February until the end of April or start of May is the spawning season. The larger the iguana, the more eggs it will lay. The smaller ones will lay about twenty-odd eggs, and the larger ones will lay 70 to 80 eggs.

Our adversary all morning has been this creature, the green iguana – a species native to South America.

Chen Tien-hsi
National Pingtung University of Science and Technology
The green iguana is indigenous to area from southern Mexico, all the way down to Argentina and northern Brazil. Basically, it belongs to the tropics. It is a tropical animal. How did it end up in Taiwan? Well, in the international pet market, it is one of the most widely sold reptiles. There are millions of them sold annually.

In 2001, Taiwan began allowing the import of the green iguana, which led to a surge in their popularity among Taiwanese pet owners. The delicate appearance of baby iguanas captures hearts. However, in adulthood, they can grow as large as 2 meters.

Cheng Yung-yu
Pingtung County Department of Agriculture
They continuously grow until they become adults. When their bodies are fully developed, sometimes pet owners feel they aren’t cute anymore, or they just don’t like them anymore. They may end up just releasing them into the wild.

Green iguanas primarily live in the plains, where they don’t have any natural predators. When they get released in the wild, they breed very quickly. Their numbers multiply at lightning speed.

Cheng Yung-yu
Pingtung County Department of Agriculture
Much of central and southern Taiwan is open country, most of it farmland. Since there are so many crops, there is plenty of food for the iguanas. Add to this the fact that these animals are out in the wild with no natural predators. They end up breeding very quickly.

In the countryside, there’s now a large feral population of green iguanas. Pingtung, Kaohsiung and Chiayi are where most of them are found, and some can be spotted in Hualien and Taitung. They have been a disaster for farmers.

Iguanas are herbivores, and they mostly eat vegetables and fruit. They feast on farmers’ fields as if digging into a buffet.

Lin Mei-man
Farmer
Take a look at the peanuts. As you can see, this side here hasn’t been eaten by them. When they show up, they come out of the irrigation channel over there. When they climb out of the channel they start to eat, but when people show up they get scared off. So that side there was eaten by them and I replanted it. The difference between where they fed and where they didn’t feed is right there.

A green iguana will survey the terrain to look for food, and will then gorge itself once it finds what it’s looking for. At their wits’ end, farmers have no option but to seek assistance from the county government, hoping that someone with expertise can remove the iguanas from the land.

They’ve scattered now. Normally what we do in this situation is, we keep searching for them. When animals scatter, they won’t always come out of hiding. That’s the biggest challen