Geologically speaking, the Hawaiian islands are relatively new. They were formed by volcanic eruptions only 70 million years ago, compared to the 200 million years it has been since the formation of North America when Pangea drifted apart. But, over the millennia, Hawaii has been a unique landmass that has been continually changing while remaining an untouched tropical paradise. Volcanic activity constantly changes the Hawaiian landscape, while conservation efforts to preserve the natural wonders of the islands have been mostly successful.
One such example can be found in the Kalalau Valley in the Nā Pali Coast State Park on the northwest side of the island of Kaua’i. Kalalau is known as a biodiverse hotspot as explained by Kaua’i’s National Tropical Botanical Garden (NTBG) research biologist Kenneth R. Wood. “When examining floristic diversity throughout the Hawaiian Islands, no other valley compares to Kalalau in the number of its unique species,” he said. “Kalalau Valley also contains the highest number of threatened plant species, with 51 that are currently federally listed as endangered.” However, as the valley is surrounded by cliffs reaching up to 2,000ft high, it is highly inaccessible. No motor vehicles can enter the valley, the only way to legally enter is by hiking or kayak.
For NTBG scientists, this makes it very difficult to conduct research missions. For years NTBG has relied on costly and time consuming helicopters to locate species of interest. Then, a hiking trek can sometimes be planned to scout an area, repelling down a cliff when possible. A few years ago, NTBG was able to purchase some new equipment to assist in their missions that has proven very successful, drones. Ben Nyberg, a drone specialist with NTBG, has been amazed at how much data he can collect with a drone. Data that has led to the rediscovery of a plant species that had been suspected extinct.
With a combination of intuition from years of experience and flying the drone in a grid pattern along cliff faces, Ben records GPS locations of interest for further drone examination. Using this method, he spotted something peculiar in January 2019, 500-600ft below a cliff ridgeline. The plant he found with the drone was a Hibiscadelphus woodii, endemic to Kaua’i, first discovered in 1991, last seen in 2011, recorded as extinct in 2016. Scientists had tried to produce the plant in a lab setting but failed.
So when Ben located that first plant with his drone, followed by two more later on, he and his colleagues were beyond excited. At the time the plant had yet to flower, so spotting it had been even more difficult. But with Ben’s expertise and the drone’s agility and HD camera, a once extinct plant now has a chance of reemergence. The team had been hoping to get up close to the plants for examination and to collect samples. Unfortunately, the plants were in far too dangerous a location to consider repelling to reach them.
Thankfully, Ben’s drone can collect far more data than just visual confirmation of Hibiscadelphus woodii’s existence. Sensors on a drone can measure atmospheric data such as temperatures, salinity, and wind conditions. This information will give the team at NTBG an idea of the ideal conditions for the plant’s survival. To further research, the team from NTBG began looking into a drone with greater capabilities. The goal is to have a drone that could collect soil samples and even delicately collect plant cuttings. “I think there’s really unlimited possibilities,” Ben said. “There’s so many different ways that this technology can be used in so many different fields.”