September 10, 2024

Janessa Angela Alerre 

11th Grade

George Washington High School 

In the past 3,500 years, CHamorus have taken advantage of the coconut – locally known as the niyok – and found a variety of ways to use it. For instance, coconut meat can be grated and used in kelaguen, a dish made with shrimp or chicken, and grated with coconut and lemon. It can create a sweet treat that’s popular among young children, coconut candy. However, people aren’t the only ones enjoying the niyok, as an invasive species has come to share it with us.

On September 11, 2007, an invasive species, the coconut rhinoceros beetle, was discovered in Guam.  The beetle’s population then skyrocketed, as prior to the invasion, coconut trees were the second most common tree on the island. So, how has this tiny creature affected the environment?

The coconut rhinoceros beetle has four life stages which are the egg, grub, pupa, and adult. Fortunately, only the adult stage can cause significant damage. Grubs get their nutritional needs from decaying vegetation. However, adult beetles will fly to the tree, pierce the top layers of the crowns by using their horn and forelegs, and drink the sap. Although they do not feed on the leaves, they dig holes through them as they make their way to the white tissue at the interior of the crown. Also, the palms of the tree can be killed if many coconut rhinoceros beetles attack at the same time—which is what Guam is currently experiencing. Although they attack and damage coconut palms, they can also feed on other crops such as bananas, sugarcane, sisal, pineapples, papayas, taro, and date palms. 

There have been a plethora of attempts to prevent the coconut rhinoceros beetle from spreading since its arrival. For example, in 2012, the Plantwise Knowledge Bank reported on a new control method, which was utilizing Metarhizium fungus. Unfortunately, the coconut rhinoceros beetles in Guam were susceptible to this. Furthermore, general sanitation practices were implemented to reduce breeding sites and limit population growth. But, these were proven ineffective, as it’s nearly impossible on a 210 square mile island with dense jungles, and military bases. Moreover, trained dogs were used to determine the species' breeding sites. Yet, it was costly and difficult to reach areas beyond the dog’s capability. Additionally, the U.S. Department of Agriculture’s Animal and Plant Health Inspection has funded $1.7 million to go to Hawaii and Guam, in hopes of combating the spread. Still, the eradication of the coconut rhinoceros beetle seems unlikely. So, the best option is to repress the population and manage it.