Welcome to the Invasive Informant, KISC works across Kaua’i to prevent, control, or eliminate the most threatening invasive plant and animal species in order to preserve Kauaʻi’s native biodiversity and minimize adverse ecological, agricultural, economical, and cultural impacts.
In late May, 2 Coconut Rhinoceros Beetles (CRB) were recently trapped on Kaua’i near the Līhuʻe Airport and around the Līhuʻe Transfer Station. KISC found both during routine monitoring of CRB traps placed for early detection around ports of entry as part of the Mamalu Poepoe program. This is the first detection of CRB on Kaua’i.
CRB is an invasive pest originally native to Southeast Asia. It attacks coconut palms by boring into the crowns or tops of the tree where it damages growing tissue. The damage can significantly reduce coconut production and, even, kill the tree. If its preferred food sources are unavailable, the beetle can shift to feed on other palms and tropical crops.
CRB are quite large, measuring one-and-a-half to two inches in length. Their bodies are shiny dark brown or black and as their name implies, coconut rhinoceros beetles have horns on their heads. The CRB larva, or grub, also quite large, is light colored and can grow up to four inches.
Until now, Coconut Rhinoceros Beetles were only known to occur on ʻOahu. Since the first Kaua’i detection in May, rapid response teams from the University of Hawaiʻi – CRB Response Team, KISC, HDOA, and other partners have been surveying for possible breeding sites and suspect CRB palm damage island-wide. Additional monitoring traps have also been placed at high-risk sites across the island. 2 small CRB breeding sites have been confirmed. Early detection and rapid management response are essential to safeguard Kaua’i from long-term CRB impacts.
There are numerous ways CRB may have found its way to Kaua’i, including hitchhiking on cargo or baggage, or in compost, mulch, or green waste.
Regular visual inspections of coconut trees are recommended. Watch for large v-shaped cuts in the crown of your palm trees or look for large bore holes at the base of palm fronds.
Early detection of infestations increases the chance of eradicating this pest on Kaua’i. Please regularly check your coconut, royal, and fan palms for CRB damage; and all compost bins and green waste for CRB larvae. If you spot a CRB or suspect a coconut palm tree is being attacked by a coconut rhinoceros beetle, you can report it at the state’s toll-free Pest Hotline at 808-643-PEST or 7378. You can also find more information on our CRB Pest page.
The Invasive Informant is brought to you by the Kaua’i Invasive Species Committee, a project of the Pacific Cooperative Studies Unit at University of Hawaiʻi Mānoa.