Battle to beat coconut rhinoceros beetle: UH Hilo researchers conduct aerial survey in Kona
The goal of the survey was to search for mulch and green waste piles so the Big Island Invasive Species Committee can better target their ground surveys for CRB grubs and beetles.
By Susan Enright/UH Hilo Stories.
Researchers from the University of Hawaiʻi at Hilo conducted an aerial survey aboard a helicopter in Kona last week, using high powered cameras and global positioning systems in search of likely habitats and signs of the invasive and destructive coconut rhinoceros beetle.
The researchers from UH Hilo’s Spatial Data Analysis and Visualization (SDAV) Laboratory are working collaboratively on the survey project with the Big Island Invasive Species Committee (BIISC), a nonprofit of the UH Pacific Cooperative Studies Unit based in Hilo.
For the survey, the helicopter was piloted by David Okita from Volcano Helicopters. BIISC was represented by Dustin Swan. From the SDAV lab were Andrew Meyer, a research assistant, and Olivia Jarvis, a geospatial research associate.
“The goal of this survey was to fly over residential areas to search for mulch and green waste piles so BIISC can better target their ground surveys for CRB grubs and beetles,” says Jarvis, a UH Hilo alumna with a bachelor of science in environmental science and a master of science in tropical conservation biology and environmental science. The team also hoped to catch any damage to coconut trees, a sign of CRB.
The Spatial Data Analysis and Visualization laboratory at UH Hilo applies geospatial tools to environmental problems of local significance such as the invasive beetle. The lab uses a suite of geospatial technologies such as small unmanned aerial system (sUAS) platforms, LiDAR, and hyperspectral imaging, to support ongoing research and educational projects. This includes the use of helicopters to capture thousands of high resolution images per flight later woven into a digital mosaic filled with visual data for researchers to analyze.
Flight day
The aerial survey in Kona was done on October 14 between 8:30 and 10:00 a.m. On flight day, Ryan Perroy, founder and director of the SDAV lab, joined Jarvis and Meyer to set up the camera on the underside of the helicopter.
Meyer, also an alum of UH Hilo with a bachelor’s degree in environmental science (2024), specializes in geographic information systems.
“My main contribution on the day was to help set up SDAV’s helicopter imaging rig, which allows us to securely mount visual cameras for helicopter based mapping operations,” says Meyer. “I was also providing our skillful pilot, David Okita, a flight guide to ensure we effectively map the area of interest.”
The researchers flew over about 4,000 acres at 500 feet above ground level in a “lawn mower” pattern.
“Once the cameras were live, we took off just before 9:00 a.m. on the 14th, and ferried to the start of our imaging area,” says Meyer. “From here, we followed a specific flight plan at the necessary altitude, speed, and spacing between lines to systematically map the area identified by BIISC as a priority.”
During the flight, Meyer directed pilot Okita with the flight lines; both Meyer and Swan from BIISC observed the ground to take note of mulch piles and palm damage they could see from the air and recording a global positioning system or GPS point to look at later in the imagery.
The flight path included residential neighborhoods and neighboring infrastructure, as CRB has been detected in and around the area.
“Thankfully, David Okita’s ability to fly steady and straight for all these flight lines helps make our imagery more useful for geospatial mapping,” says Meyer.
Both Jarvis and Meyer note that the imagery is being used for the purpose of identifying potential CRB activity only, and it will not be shared or distributed publicly — unless no identifiable characteristics are present — to protect residents’ privacy.
Back to the lab
When the flight was finished, the imagery was brought to the Hilo lab, where research assistant Tori Valdez, geospatial data assistant Andrew Tabaque, and Jarvis split up the 6,000 images taken to analyze the data.
“After the imagery is collected, we offload this data and use post-processing software to essentially stitch these photos together, which creates a 2D imagery layer, often referred to as an orthomosaic,” says Meyer. “This orthomosaic is geospatially referenced, and this helps us pinpoint areas of interest in the imagery itself. In this case, Olivia, Tori, and Andrew are looking for damaged coconut trees, mulch piles, or other suspect signs of CRB.”
“We scanned the images for potential mulch pile and palm damage suspect areas,” says Jarvis. “Tori is finishing the map this week to share with BIISC so they can start their ground survey work.”
Meyer says “the hope is that performing aerial imaging of these areas can be quicker than searching on the ground, whilst also being an effective alternative.”
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Story by Susan Enright, public information specialist for the Office of the Chancellor and editor of UH Hilo Stories. She received her bachelor of arts in English and certificate in women’s studies from UH Hilo.
