Drones hunt down rare plants in Hawaii by going where people can’t

There’s something inherently creepy and annoying about drones buzzing over our heads — a frequent backyard irritation in cities like New York. But it turns out, a drone’s spying abilities can be useful: an uncrewed drone discovered a super-rare plant on a steep cliff on the Hawaiian island of Kauaʻi. The discovery wowed botanists — and shows how technology can help conservationists in their fight against extinction.

“We were really excited,” says Ben Nyberg, a GIS specialist and lead drone pilot at the National Tropical Botanical Garden, a nonprofit institution charted by US Congress in 1964. Nyberg was flying the drone that found the plants at NTBG’s 1,000-acre Limahuli preserve.

The 1,000-acre Limahuli preserve on the Hawaiian island of Kauaʻi. Photo by Alessandra Potenza / The Verge
“It’s amazing how much of a game changer this is for field botanists,” Merlin Edmonds, a conservationist at NTBG, said in a statement. Edmonds was training to be a drone pilot with Nyberg when the plants were spotted. “Discovering a population like this would usually take days of searching under life-threatening conditions, but this happened in 20 minutes.”

Drones are frequently used in conservation. In Africa, drones are deployed to catch poachers slaying endangered elephants and rhinos — especially at night, when they’re most active but harder to see. The same is happening in Nepal, where poachers target elephants, rhinos, and tigers. The vehicles are also used to study river dolphins in the Amazon, as well as orangutans in Indonesia.

In Hawaii, the focus is on preserving native species, especially plants. For instance, the plant discovered by drone is a critically endangered species called Laukahi that’s being wiped out by invasive goats that love munching on its leaves. The Laukahi plants have been pushed to steep cliffs that goats can’t get to — but humans can’t get there either. So until this discovery, people thought fewer than 25 individual Laukahi plants remained in the wild. The drone footage added about 10 more plants, Nyberg says.

NTBG acquired its first drone in February, and has been using it to scour remote areas where many native species are taking refuge. Hawaii’s plants are so vulnerable because they evolved in isolation for millions of years, so they lack the defense mechanisms to fend off invasive species — like weeds, rats, goats, and pigs — imported by people through the years. Several individuals of different endangered plants were discovered through the use of drones, says Kawika Winter, the director of Limahuli Garden and Preserve, but the Laukahi is the rarest.

The discovery was “very special” to Winter, because of the importance of Laukahi in the native Hawaiian culture. The plant has been used in traditional Hawaiian healing to disinfect wounds, as well as to treat boils and high blood pressure, he says. When Winter was learning Hawaiian herbal medicine, his teacher — a seventh-generation healer — told him about Laukahi, and the fact that the plant was extremely rare, Winter says. Finding new Laukahi plants gives Winter hopes that the species can be brought back to Hawaiian forests, and used to perpetuate native Hawaiian culture.

“When you get to plants that are this rare, they are barely clinging to existence in the forest and they’re no longer enriching humanity,” Winter says.

There’s also value for the ecosystem: forests are more resilient when there are more species living there, since each species plays a very crucial role to help other plants and animals thrive as well. “If there’s a hurricane, or forest fire, or some kind of catastrophe, the most biodiversity there is, the quicker that system can bounce back to a state of health,” Winter says. It’s similar to what happens to your wallet. “If you have a more diverse portfolio of investments, if there’s an economic collapse, you’re still gonna have money,” he says.

Botanists won’t be able to get to the Laukahi plants on the cliffs of Limahuli preserve. Winter hopes that, in the future, drones with arms could maybe collect some flowers — and precious seeds. Until then, NTBG’s drone will keep flying over cliffs, filling the air with annoying buzzing, but also performing an invaluable task.