Coconut Rhinoceros Beetle Control: Latest Methods in Hawaiʻi
For the most current detailed list of chemical and biocontrol control methods, visit: Biocontrol and Chemicals for CRB Control
The Coconut Rhinoceros Beetle (CRB) continues to pose a significant threat to niu (coconut palms), endemic loulu palms, hala (Pandanus tectorius), banana, and many other palm trees and other important plants across Hawaiʻi, with established populations on Oʻahu and Kauaʻi. As we enter the second decade of dealing with this pest, multiple control options have been assessed and are being employed to manage this invasive pest.
Chemical Control Methods:
Currently, several pesticide options show promise in CRB management. Pyrethrins and pyrethroids, including cypermethrin and lambda cyhalothrin, remain effective for canopy spray applications, with synthetic versions providing up to three months of protection. Neonicotinoids like imidacloprid and dinotefuran have proven successful when applied through injection methods. A newer finding shows that basil oil, applied at three-week intervals, acts as an effective repellent in field trials.
Oryctes rhinoceros nudivirus (OrNV) By Bernhard Zelazny – CC BY-SA 4.0
Biocontrol Developments:
The state is actively pursuing biological control options as long-term solutions. The Oryctes rhinoceros nudivirus (OrNV) is currently undergoing the permitting process for importation to Hawaiʻi. While several fungal options – including Metarhizium anisopliae, Metarhizium majus, and Beauveria bassiana – have shown effectiveness, they are not yet registered with federal and State regulatory agencies for use in Hawaiʻi. Local research continues on these promising biocontrol agents.
CRB Control Starts with You – Individual Action Matters:
In areas where CRB has been detected, community participation is crucial. While wild and domesticated predators like chickens and pigs may opportunistically feed on CRB and could be used as a tool in the management toolbox, their overall impact is limited. The most effective approach combines proper green waste management with targeted chemical applications when necessary, supported by ongoing biocontrol research efforts.
The path forward in CRB control relies on integrating multiple management strategies while new tools are developed and approved. Residents in affected areas are encouraged to stay informed about the latest control methods and participate in community-based management efforts to protect Hawaiʻi’s valuable palm resources and agricultural security.