Crews have initiated a search for breeding sites of the invasive coconut rhinoceros beetle (CRB) in the Kona area, where around 24 of these beetles have been identified since they were first detected in the region in March.
Until last year, Hawaiʻi Island had been free from CRB, but sightings in Waikōloa marked the beginning of their presence on the island. In March, multiple sightings south of Kona, especially near the Elison Onizuka Kona International Airport and the Hawaiʻi Ocean Science and Technology Park, sparked concerns about their spread.
Most recently, three adult beetles were discovered at Hawaiʻi Community College’s Pālamanui campus, with another individual found a few miles north at Kīholo Bay.
Local officials reported that, as of Tuesday, approximately 24 coconut rhinoceros beetles have been located in or around Kona. Unfortunately, the majority of these findings involve adult beetles, prompting crews to intensify their search for potential breeding sites to prevent further dissemination.
Franny Brewer, the program manager for the Big Island Invasive Species Committee, stated, “We think that this is all from one initial clutch, and in that case, these are all brothers and sisters that we’re finding, but they all came out of one area that’s maybe a couple feet across at most. So we’re trying to find where that is.”
Brewer was actively participating in the search at Kīholo Bay on Tuesday. She expressed concerns that if a breeding site is indeed present, the further spread of the beetles is not unexpected.
The pressing worry is that these beetles are mating, which could lead to a new generation emerging in four to five months. Brewer emphasized the urgency of addressing potential breeding environments composed of compost, mulch, and green waste, stating, “Now we’ve really gotta be on it with our breeding material…We have four to five months before the next generation starts to emerge, where we have a chance to get in there and find those babies and get rid of them before.”
Coconut rhinoceros beetle populations were first reported in Hawaiʻi back in 2013, yet their expansion beyond Oʻahu wasn’t registered until this year when they were found in Maui, Hawaiʻi Island, and Kauaʻi.
The CRB is notorious for burrowing into, feeding on, and potentially killing palm trees, which has led the City and County of Honolulu to undertake the removal of several palm trees on Oʻahu, where the beetle is now prevalent.
In response to the incursion of the beetle, various agencies, including the state Department of Agriculture, have been actively involved in managing the situation. Jonathan Ho, the manager of the Plant Quarantine Branch, mentioned, “The department has been treating, along with a bunch of landowners, as many trees as we can get our hands on. If there are any beetles that are emerging from mulch piles that we’re not aware of, they will succumb to the pesticide treatments.”
The Department of Agriculture is collaborating with the County of Hawaiʻi to advise businesses and the public against the movement of materials that could potentially harbor CRB, such as mulch and other decomposing plant material. This request is expected to be issued in the coming week, particularly aimed at those involved in delivering breeding material.
A similar voluntary request was made last December in response to the avian flu spread.
Simultaneously, the DOA is working on interim regulations that are part of a long-term strategy to curb the spread of CRB.
During a recent Board of Agriculture meeting, Ho reported the discovery of three CRB larvae in two shipping containers on Lānaʻi, which had contained plants. The containers were subsequently checked by inspectors and buried to eliminate any remaining beetles or larvae.
image source from：hawaiipublicradio
