2 invasive coconut rhinoceros beetles found on Kauaʻi in traps near green waste station
Two coconut rhinoceros beetles have been found on Kaua‘i, in traps near a green waste transfer station close to the Līhu‘e Airport.
These are the first detections of the beetles (Oryctes rhinoceros) outside of O‘ahu.
On May 31, a survey crew from the Kaua‘i Invasive Species Committee found a live beetle in one of the traps near the green waste transfer station. On June 2, survey crews found a dead beetle in another trap nearby.
The coconut rhinoceros beetle is a serious pest of palm trees, primarily coconut palms, because the adult beetles bore into the crowns of the palms to feed on the tree’s sap. New, unopened fronds are damaged in this way and when fully opened, may break and fall unexpectedly.

If the beetle kills or damages the growing point of the palm, the tree may die. Secondary fungal or bacterial pathogens may also attack the wounds caused by the beetle, thereby killing the tree as well.
Tree mortality after a beetle attack has been reported to be anywhere from 10 to 50%. Dead trees then become a safety hazard as they may fall unexpectedly after the trunk rots, potentially resulting in bodily injury or property damage.
It is a major pest of palms in India, the Philippines, Palau, Fiji, Wallis, Nukunono, American and Western Samoa and Guam. It is still not known how the beetles arrived in Hawai‘i.
The Hawai‘i Department of Agriculture has been systematically dealing with the issue since the coconut rhinoceros beetle was first detected on O‘ahu in 2013. It now will expand the use of its incident management system to include Kaua‘i, with staffing from the Kauaʻi Invasive Species Committee. And, four members of the beetle response team on O‘ahu will be deployed to Kaua‘i this week to help.
“When [the coconut rhinoceros beetle] was first detected on O‘ahu about 10 years ago, early eradication efforts were hampered by the lack of funding and lack of information about the pest,” said Sharon Hurd, chairperson of the Hawai‘i Board of Agriculture. “We want to make sure this does not happen on Kaua‘i and we appreciate the assistance of partner agencies and all the research that has gone into CRB eradication and control.”
The response plan for Kaua‘i includes:
- Conducting visual surveys within a one-mile buffer zone of the first detections
- Deployment of additional traps at 25 priority sites, including the use of cameras and ultraviolet traps
- Possible fumigation of green waste at the transfer station
- Possible deployment of beetle-detector dogs after initial surveys by the response team
- Review of the possible pathways of introduction of the beetle to uninfested areas
It also has led to the indefinite closure of green waste disposal at the Līhuʻe refuse transfer station.
Partner agencies in the response also include the Hawai‘i Invasive Species Council, the Department of Land and Natural Resources, the U.S. Department of Agriculture and the Hawai‘i Department of Transportation.
The University of Hawai‘i also has also been an important collaborator in the beetle program, leading the effort to develop new traps and using drone technology to apply insecticides.
“Much has been learned over the past years about the CRB life cycle, detection, management, containment and treatment protocols,” said Helmuth Rogg, administrator of the state Plant Industry Division. “With these new detections on Kaua‘i, we are focusing a rapid response toward eradication.”
Surveillance for the beetles has been ongoing on all neighbor islands, including Kaua‘i, where pheromone traps have been used for more than five years in strategic locations at Nāwiliwili Harbor and Līhu‘e Airport. The traps are used for early detection of beetle infestations. More than 3,000 beetle traps have been deployed around O‘ahu to track infestation areas.
Green waste provides an optimal breeding environment for the beetle and residents on all islands are urged to check their compost bins and green waste for beetle larvae. In an effort to stop the spread of the beetle to neighbor islands, the state Department of Agriculture issued an interim rule in July, 2022, restricting the movement of beetle host material within the island of O‘ahu and from O‘ahu to neighbor islands.
Beetle host material includes entire trees, green waste, compost, mulch, trimmings, fruit and vegetative scraps and decaying stumps of palm and palm-related plants.
The USDA currently provides the state Department of Agriculture with about $2 million per year for beetle response efforts and about $350,000 per year for canine support. Additional moneys were appropriated this legislative session pending Gov. Josh Green’s approval.
The beetles were first detected in Hawai‘i in Dec. 2013 at Joint Base Pearl Harbor-Hickam and have since been detected in West O‘ahu, from Māʻili to Pearl City and north to Kunia. Infestations have also been detected on the North Shore from Mokulē‘ia to Kahuku and in Waimānalo. There had been no detections of the beetles on islands other than O‘ahu, until now.
Tissue samples of the beetles found on Kaua‘i are being sent to the University of Hawai‘i for molecular identification analysis to try and trace the origin.
Reports of possible beetle infestation may be sent to the beetle response team at 808-679-5244 or email info@crbhawaii.org or the state’s toll-free Pest Hotline at 808-643-PEST (7378).
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