Since I Retired, I've Started Gardening—for Iguanas
By Peter Harlow
In July 2024, a small party consisting of Joeli the ranger, two young men from his village, two volunteers, and me boated to uninhabited Monuriki Island in western Fiji. The purpose of the trip was to determine the survival of more than 700 tree seedlings and more than 10,000 seeds we had planted there in 2022 and 2023. We were very pleased to see that the forest looked lush, lots of shrubs and understory below, and a full canopy of trees above. But it wasn’t always like that.
A Precarious Situation
Fiji’s only Wildlife Ranger, Pita Biciloa, and I first landed here in 1998, to survey the abundance of Fijian Crested Iguanas (Brachylophus vitiensis). Pita was the ranger for the uninhabited island of Yadua Taba, about 150 km north of Monuriki, which was home to the Crested Iguana Sanctuary. After getting permission from the owners of the island, they dropped us by boat with our food, water, and tent, and promised to return in five days.
A quick walk in the forest behind the beach and Pita was angry and dismayed. “There are no iguanas here, there is nothing for them to eat!” he declared. It was true. The ‘”forest” looked more like a desert, just open sand, with no understory plants or ground vegetation. Goats had eaten almost everything and had even climbed into the few remaining edible tree species to eat their leaves. Most of the trees and seedlings were of one species, called Vao in Fijian; it is so toxic that even starving goats can’t eat it. Fijian iguanas, like goats, are 100% herbivorous, and Pita knew what plant species the iguanas could eat.
No Food, No Iguanas
In five days and nights of searching we found 13 crested iguanas. These were all found in the occasional “edible” tree species still surviving in the forest. Our population estimate for the entire island was less than 100 iguanas. “If they ever get rid of the goats, we should come back and plant some Cevua, Vesi Wai, Qiqilla and Wa Vulu,” Pita mused on our last night on the island, listing off the Fijian names for the iguana’s favorite food trees. These were now all extinct on Monuriki. None of these common native species had survived 40 years of forest burning and goat grazing.
In 2011 the goats were removed from Monuriki at the request of the island’s owners. Almost immediately the vegetation started to recover, but the extinct tree species, the iguana’s and the goat’s food favourites, were not there to recover. Of the 5 or 6 most important food species for the crested iguana only one species remained, and it was uncommon.
Gardening for Iguanas
So that’s how, in 2022 as a recently retired reptile biologist, I became a gardener, albeit on a remote and uninhabited island over 3,000 km from my home in Australia. The International Iguana Foundation funded our project to reintroduce these important iguana food tree species at two sites on Monuriki. Sixteen km from Monuriki is Castaway Island, a pristine, forested island with a tourist resort that has the best native dry forest remaining in western Fiji. It is from there we collect our seedlings and ripe fruit of Cevua, Vesi Wai, and Qiqilla.
We have tried a variety of techniques, from growing seedlings in pots for a year then directly transplanting them with their roots carefully wrapped in cloth, to sowing thousands of ripe fruit directly in the ground. The herbivorous iguanas eat the leaves and flowers, but they especially like the small, fleshy fruit. The iguanas not only pass the fruit seeds through their gut unharmed, but, importantly, they will also spread the seeds around the island.
Rebuilding Forest
Our July trip this year confirmed that the best way to directly transplant seedling Cevua and Qiqilla was to wrap their roots in cloth, while for Vesi Wai, seedlings grown from seed in pots for the first year did best. Next year, 2025, will be our fourth year of this project, and already some of our first Vesi Wai seedlings are over four meters in height, while our Cevua and Qiqilla seedlings are thick and bushy, but slow growing. It will be a few more years before our “new” trees fruit and start to spread across the entire island, with the help of hungry iguanas dispersing the seeds.
A big thank you to our long-term supporter The International Iguana Foundation, and our wonderful local partners the Mamanuca Environment Society, Castaway Island Resort, the Mataqali Vunaivi and the Fijian Ministry of Forestry.
