BALI, Indonesia — “We didn’t have electricity in our village of Taro, near Ubud, until I was 12 years old,” says conservationist Wayan Wardika. To find their way through the rice fields at night, Wardika and his schoolfriends would capture fireflies and put them in jam jars, so they could use them as lanterns. “We [could] grab a handful of fireflies with our hands,” he says.

But when Wardika arrived home clutching his makeshift lantern, he would also receive a scolding from his grandparents. “I was told that the fireflies are considered to be the presence of our ancestors,” Wardika says. Another traditional Balinese belief is that when a person dies, the firefly guides the soul to the afterlife.

Work in the cruise ship industry took Wardika far from home. And each time he returned to Bali, he couldn’t help but notice that the fireflies were disappearing. In 2020, after Wardika had moved back to Bali, he decided to launch Indonesia’s only firefly conservation lab. With a love of fireflies, and following hours of self-guided research, he decided to help protect the lightning bugs for future generations.

Fireflies are beetles in the family Lampyridae that can emit light to ward off foes and attract mates. Sensitive to pollution and environmental changes, fireflies act as mini bioindicators, showing how healthy an environment is. Fireflies are also a natural pest control: The carnivorous larvae feed on snails, which are fond of young rice plants.

However, loss of habitat, the use of pesticides, and light pollution have all led to a dramatic drop in numbers. In 2024, the IUCN, the global wildlife conservation authority, announced that four species in Southeast Asia are now facing extinction.

Because they breed in soil or water, habitat loss and pesticides can affect firefly populations dramatically, but so can light pollution. “The more buildings there are, the more lights there are, and [this] affects their communication system,” Wardika says.

He self-funded the Bring Back The Light firefly laboratory, which he built underneath the palm trees planted on his family farm. One room is filled with floor-to-ceiling shelves of glass jars that contain firefly eggs or larvae, originating from fireflies found in the village.

Here, each jar turns into a mini torch at night, as the larvae glow in the dark when the light goes down. Another room contains identification equipment such as microscopes and charts of fireflies from Thailand and Australia, which Wardika’s team uses to try and identify the eight local species they’ve found. There are more than 400 species of fireflies in Southeast Asia, yet the team still hasn’t been able to match the eight as-yet-unidentified species it’s breeding in the lab.

There’s also accommodation on site for researchers and volunteers. The Bring Back The Light team may have started with just Wardika, but it now includes three biologists from the city of Yogyakarta who work full-time at the firefly laboratory. To help fund the lab, they hold daily firefly tours and sell organic produce grown on the farm. They also receive donations from individuals who want to support the project. The team has identified two general types of fireflies, which they call terrestrial and semiaquatic. The terrestrial larvae grow in the soil, while the semiaquatic breed on the water. The team collects the fireflies at night using jars, then transfers them to a large terrarium where they can mate.

After the terrestrial fireflies have laid their eggs in soil, the team moves the eggs to cotton pads for monitoring. The semiaquatic fireflies lay their eggs on the leaves of the aquatic plant kapu-kapu (Pistia stratiotes), so the team then moves the egg-covered leaves to individual petri dishes to protect them. They also take steps to make sure there’s no crossbreeding. “We give each larvae a code, so we know their history when they turn into an adult,” says biologist Margaretha Noviani.

The firefly lab has already bred 40 terrestrial fireflies, some of which have been released and others used to breed the second generation of fireflies in captivity. To help further the lab’s research, the team has connected with firefly scientists in Malaysia and Australia and is also working with universities in Indonesia on grant applications.

“I think that Bring Back The Light is a really good initiative,” says entomologist and conservationist Wan Faridah Akmal Jusoh, co-chair of the IUCN’s firefly specialist group. “We are actually in the process of understanding life cycle of fireflies, which is what’s lacking at the moment. So captive breeding is important in order for us to understand each life stage of different species.”

Identifying a firefly is hard work. “Everybody faces the same [challenge],” Jusoh says. “To help conserve the firefly they need to know more about the species they are dealing with.”

Jusoh says she is one of just two scientists working on firefly taxonomy in Southeast Asia and the Indo-Pacific. As customs and excise prevents the Bali team from sending the insects to Jusoh’s lab at Monash University Malaysia in Selangor, she says she plans to visit the island to help identify the ones it has found.

Going organic

Wardika says that while he recognizes the place of fireflies in the ecosystem, his parents, like some of the other older neighboring farmers, thought his decision to breed them was a crazy idea. “My parents said, ‘Why are you going to breed fireflies, when you can breed chickens? At least they make eggs.’”

Now, he says, his parents are fully behind the idea and take delight in welcoming the ecotourists to the farm to see the fireflies.

To help persuade his fellow farmers to ditch the pesticides, Wardika turned his whole farm into an organic demonstration plot. He not only grows plants that can earn farmers an income, but firefly-friendly foliage, such as coffee, durian and moringa, which the team noticed the terrestrial fireflies like to congregate around.

In 2023, Wardika took a course on regenerative farming in East Java province, going on to make organic fertilizer from compost, manure, fermented fruit and vegetable peelings, and a soil-friendly pesticide from tobacco. The Bring Back The Light program now distributes organic fertilizer and pesticide to the other farmers involved in the scheme.

Komang Petak owns the Fireflies Garden, a 2.5-hectare (6.2-acre) organic farm and cooking school in Taro. Not connected to the Bring Back The Light project, it also promotes the need to protect fireflies. After seeing their numbers drop in Bali, Petak started firefly tours during the COVID-19 pandemic to help raise awareness.

He decided to take his farm organic in 2017 as he wanted to provide his family with nutritious food. When he made the change, he also noticed a boost in firefly numbers on his land. “Maybe because of our actions [of] not using pesticides that’s why there are fireflies in our place,” Petak says.

He adds he doesn’t rely solely on the farm for an income, so he understands why going organic makes local farmers nervous. “Other farmers think it’s [a] good [idea], but none of them want to follow us [because] without pesticides pests are difficult to control,” he says.

At the moment, four other farms have joined the Bring Back The Light scheme and gone organic, but Wardika says he’s hopeful that the remaining 30 farms in the area will also join, particularly as many of the farmers are relatives.

His plan is to create a blueprint that will enable other locations in Southeast Asia to adopt the same scheme. “I have so many reasons to stop, this is not my field of expertise,” Wardika says. “But I always look for one reason to continue and I always find that reason. And that reason is always for the generation to come.”

Banner image: Conservationist Wayan Wardika in the farm. Image courtesy of Bring Back The Light.

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