Coconut Rhinoceros Beetle (Oryctes rhinoceros)
The coconut rhinoceros beetle (CRB) is a large scarab beetle that is native to Southeast Asia. It was accidentally introduced from Sri Lanka to Samoa in 1909 and is now distributed throughout the South Pacific. In its native range, the coconut rhinoceros beetle can be attacked by a variety of predators at all life stages and is also susceptible to a fungus and a virus that keep the populations in check. CRB is a one of the most damaging pest of coconut palms, and could pose a threat to other species including Hawaii’s only native and endangered palm, the Loulu (genus Pritchardia).
- Adult coconut rhinoceros beetles are about 30-60mm long (about 2 inches) solid, black beetles.
- Both male and female CRB have a horn on their head, though the male’s horn is more than twice as long as the female’s.
- Eggs are laid and develop inside rotting coconut logs, mulch or compost piles.
- Eggs hatch into C-shaped, larval grubs that can grow to be 60-105mm (2.3-4.1 inches) long.
- Grubs feed on decaying wood and organic material for about 4-6 months before pupating.
- After a pupation phase of about 2 weeks, adults emerge.
- Adult CRB are active at night and live between 4-9 months.
Oriental flower beetles have been in Hawai’i since 2002 and are widespread. The oriental flower beetle is the largest beetle on O’ahu and is often mistaken for the Coconut Rhinoceros Beetle, however there are some distinct difference that can help you identify between the two beetles. PHOTO COMPARISON
- Oriental flower beetle do not have an upturned “horn” like CRB.
- Oriental flower beetles are about one inch long (about half the size of CRB).
- Oriental flower beetles have mottled white patches, while CRB are solid black.
- Larval stages look very similar, but oriental flower beetle grubs wiggle on their back, while CRB grubs wiggle on their side.
- Adult CRB bore into the crowns of coconut palms to eat developing leaves.
- CRB damaged palm fronds have distinct geometric notching, appearing to have been cut by scissors.
- The damage to palms and their fronds can outright kill the tree or leave it susceptible to disease.
- Grubs can be spread through green waste transfer.
- Adults can spread through flight, hitchhiking and in high wind events.
- Threatens the endemic and endangered fan palms, Loulu.
- CRB also pose threats to all oil palms, pandanus trees, and banana trees.
- First detected on O’ahu in December 2013, the breeding site is limited to a four mile radius around Joint Base Pearl Harbor Hickam (JBPHH) and eradication efforts were started immediately upon detection of CRB.
- Hanging panel traps have been set across the island of O’ahu to monitor for CRB.
- Bi-weekly updates about the coconut rhinoceros beetle eradication process are available from the Hawai’i Invasive Species Council.
- OISC’s management goal for coconut rhinoceros beetle is to collaborate with the island-wide detection and eradication efforts led by the USDA and HDOA.
- If you see CRB beetles or suspect CRB damage, call coconut rhinoceros beetle response at (808) 679-5244 or email firstname.lastname@example.org.
Pest Alerts and Publications:
- CRB Brochure
- Best Management Practices
- Coconut Rhinoceros Beetle vs Oriental Flower Beetle
- CRB Wanted Poster
- HISC; Coconut Rhinoceros Beetle Response Updates
- CRB Map (Dec 2013-Mar 2018)
For more information, see:
- United States Department of Agriculture; Animal and Plant Health Inspection Service
- Hawaii Department of Agriculture; Plant Industry Division