Adult Coconut Rhinoceros beetles caught in traps set out in Waikōloa

Three invasive Coconut Rhinoceros beetles were captured on the Big Island in traps near a landfill and in Waikōloa.

The first adult beetle collected last week was caught in a camera trap at the Hawaiian Earth Recycling facility near the West Hawai‘i Sanitary Landfill. Over the weekend, two more beetles, a male and a female, were collected from a trap hosted by the Waikōloa Dry Forest Initiative.

To supplement Hawai’i State Department of Agriculture workforce in West Hawai‘i, staff from the Plant Quarantine Branch (PQB) from O‘ahu flew over today to assist in confirming the location of the CRB detections and to conduct additional surveys. 

“Unfortunately, detections of live adult beetles are an indication that CRB are breeding in the Waikoloa area,” said Sharon Hurd, chairperson of the Hawai‘i Board of Agriculture. “We ask that residents pay special attention to mulch and green waste that serve as optimum breeding conditions and report any suspected CRB or suspected CRB damage in palm trees. We need everyone’s eyes.”

Prior to the recent detections in Waikoloa, HDOA PPC and the CRB Response Team had already scheduled extensive surveying and treatment activities for the beginning of May. Plans are being developed to try new methods of treatment for palm trees. Additional detection traps will be deployed, including a new generation of smart traps.

HDO’s Pesticides Branch applied for and received a crisis emergency exemption from the U.S. Environmental Protection Agency to treat palms with the pesticide, cypermetherin, which is effective in killing CRB. The EPA authorized its use on Maui, Kaua‘i and Hawai‘i Counties.

On Hawai‘i Island, PQB inspectors have been on heightened alert for any mulch or compost material arriving on the island. Such materials transported from O‘ahu to neighbor islands are required to be heat treated or fumigated prior to shipping to kill any CRB.

Coconut Rhinoceros beetle (Oryctes rhinoceros) is a highly destructive pest native to Southeast Asia. The adult beetles feed on the growing spear of palm trees using their large horns and spiny legs to dig into the crown, causing significant and potentially fatal damage to the tree.

The beetles were first detected in 2013 on O‘ahu. The insects were identified on the Big Island in October 2023 when several larvae were collected from a private property in Waikōloa Village but no adult beetles were found at that time.

Since that detection, the nonprofit Big Island Invasive Species Committee has worked with partners from the U.S. Department of Agriculture, the Hawai’i State Department of Agriculture and the University of Hawai’i to deploy an extensive network of pheromone detection traps near the original site and in high-risk areas throughout the island.

Nearly 150 traps have been installed and additional trap deployments are ongoing.

Palm surveys of Waikōloa Village were completed by the nonprofit in February and March. No palm damage was observed, but officials say it can take several months for a damaged palm frond to unfurl and show signs of infestation.

Surveys of the new detection sites by HDOA and BIISC staff are planned in the coming days and will include support from CRB detector dog Manu and his handler, Dr. Michelle Reynolds of Hawai‘i Detection Dogs.

Coconut rhinoceros beetles will feed on many other palm species – including threatened native Hawaiian loulu. They have also been documented attacking other agriculturally and culturally important species including hala, sugarcane, banana, and taro.

The nonprofit says residents in the area around Waikōloa and Pu’uanahulu should be especially vigilant about inspecting any mulch or debris piles in their own yards, particularly those with palm waste.

All residents are advised not to move green waste out of the area. Visually inspect all mulch and soil products for larvae (grubs). Because other beetle larvae on island look similar to the invasive insect, take video and photos of the grubs from various angles.

Images can be submitted to BIISC via email at biisc@hawaii.edu, through the BIISC pages on Facebook or Instagram, or at 643Pest.org.