Australian Longhorn Beetle
Here in the islands we are so vulnerable to the invasion of foreign species because of our heavy reliance on imported materials. There is a perfect but disturbing example hitting the Big Island’s cacao industry hard right now. An insect – the Australian Longhorn Beetle – poses such a threat to the future of the cacao industry on the Big Island right now, that there is actually a $20 reward for the first ten beetles caught and turned in (alive) to the Department of Agriculture.
The Australian Longhorn Beetle is not new to Hawaii. The beetle was first spotted almost ten years ago when someone turned one in from the Orchidland area of the Big Island. There were no more reports of these imported insects until 2013 when several more specimens were turned in to the Department of Agriculture. The Longhorns have found a way to thrive and multiply over the past several years because they are now established and a huge danger to the Cacao industry on Hawaii Island’s eastside.
Longhorn beetles like hardwood. For us in Hawaii, that means things like the cacao tree, the native Hawaiian lama tree, breadfruit trees, citrus trees, koa, ohia and others. Hardwood trees are not damaged by the adult longhorn beetles. Rather, it’s the larvae. The female lays her eggs in tree trunks. When the larvae emerge, they tunnel through the tree and continue to do so as long as they can. The tunneling process weakens the wood of the tree and incapacitates the tree’s ability to obtain needed water and nutrients to grow.
The longhorn beetle is generally a nocturnal insect, so they are challenging to find. In addition, the only known treatment for Australian Longhorn Beetle infestation is to cut down the trees. Longhorn beetle infestations have already been quite devastating in other parts of our country and around the globe. If you do find one of these insects – whether on Hawaii Island or any other island – please call the Hawaii Department of Agriculture at 808-974-4146. The agriculture department is hoping to use the insects to create a substance deterrent.