New Hawaii Plant Pest: Coconut Rhinoceros Beetle

State agriculture officials are concerned about a new invasive pest discovered in Hawaii.

The coconut rhinoceros beetle is a major pest in India and the Philippines as well as Guam and other areas of the South Pacific.

So far, in Hawaii, the beetle has only been found at Joint Base Pearl Harbor-Hickam on Oahu.

The adult beetles bore into the petiole or base of the palm frond. HDOA photo.

The beetles damage palms by boring into the center of the crown where they injure young, growing tissue and feed on the sap. They also cause damage to the fronds by cutting through developing leaves as they bore into the crown.

The beetle mainly attacks coconut and oil palms, but may also attack other palm species, said officials with the state Department of Agriculture.

“The threat of the coconut rhinoceros beetle has been a growing concern in Hawaii since it turned up in Guam in 2007,” said Neil Reimer, administrator for HDOA’s Plant Industry Division. “We have initiated the strong, coordinated efforts among HDOA, USDA, UH and other partners that will be required to effectively manage this invasive pest.”

Damage resulting from the coconut rhinoceros beetle. HDOA photo.

Adult beetles are dark brown and measure up to 2½ inches in length. In their larvae form they are white in color with a brown head.

Natural enemies of the beetle include pigs, ants, ants and some beetles. They are also susceptible to a fungus and a virus, neither of which are found in Hawaii, however.

Suspected CRB on coconut and palm plants on all islands should be reported to HDOA’s PEST HOTLINE – 643-PEST (7378), which is toll-free for neighbor islands.

The beetle was first discovered at Hickam on Dec. 23, which was the same day that a population of little fire ants was discovered on hapuu tree ferns shipped from the Big Island to a Maui garden shop. The ants, which are a major pest on the Big Island where they have become established, have also been found on Oahu and Kauai.

The tiny red ants live both on the ground and in trees and can cause painful bites to humans, and cornea damage as well as blindness to cats and dogs.