A mathematical model of invasion and control of coconut rhinoceros beetle Oryctes rhinoceros (L.) in Guam.

The coconut rhinoceros beetle (CRB), is one of the most damaging pests to coconut palms causing severe economic harm. Its expansion from Asia to the Pacific in the early 20th century has been stopped by virus control. However, a new haplotype CRB-Guam has recently escaped this control and invaded Guam, other Pacific islands, and has even established itself in the Western Hemisphere. In this paper, we present a compartmental ODE model of CRB population and control. We carefully consider CRB life stages and its interplay with coconut palms as well as "the green waste", the organic matters used by CRB for breeding sites. We calibrate and validate the model based on data count of CRBs trapped in Guam between 2008 and 2014. We derive the basic reproduction number determining the CRB population growth without any control measures. We also identify control levels required to eliminate CRBs. We show that, in the absence of viable virus control, the sanitation, i.e., the removal of the green waste is the most efficient way to control the population. Our model predicts that the sanitation efforts need to roughly double from the current levels to eliminate CRB from Guam. Furthermore, we demonstrate that a rare event like Typhoon Dolphin that hit Guam in 2015 can lead to a quick rise of the CRB population.

First record of Doleschallia tongana (Lepidoptera: Nymphalidae) for Guam Island.

A single specimen of the butterfly, Doleshallia tongana Hopkins 1927, was collected on Guam Island on October 23, 2017 (13.430478°N, 144.800419°E). This is a new species record for Guam and Micronesia, indicating a geographical range expansion for D. tongana.

A new haplotype of the coconut rhinoceros beetle, Oryctes rhinoceros, has escaped biological control by Oryctes rhinoceros nudivirus and is invading Pacific Islands.

The coconut rhinoceros beetle (CRB; Oryctes rhinoceros) is a major pest of coconut and oil palm, but the discovery and release of Oryctes rhinoceros nudivirus (OrNV) in the 1960s and 70s suppressed the pest such that no new invasions of uninfested islands by CRB were reported for over 30years after implementation of the biocontrol programme. Surprisingly, a highly damaging outbreak was reported from Guam (2007), which could not be controlled by OrNV. Subsequently, new invasions have been reported from Port Moresby, Papua New Guinea (2009); O'ahu, Hawai'i (2013); and Honiara, Solomon Islands (2015). We have found that all of these outbreaks have been caused by a previously unrecognized haplotype, CRB-G, which appears to be tolerant to OrNV. PCR analysis shows that OrNV is generally present at high incidence in established populations of CRB, but is generally absent from the invasive CRB-G populations. CRB-G from Guam was not susceptible to OrNV infection by oral delivery, but injection of the virus did cause mortality. Further genetic analysis shows that CRB populations can be divided into a number of clades that coincide with the endemic and invasive history of the beetle. Analysis suggests that CRB-G originated in Asia, though the precise location remains to be discovered.

First record of Eggplant Mealybug, Coccidohystrixinsolita (Hemiptera: Pseudococcidae), on Guam: Potentially a major pest.

The eggplant mealybug, Coccidohystrixinsolita (Green) (Hemiptera: Pseudococcidae), is recorded from the island of Guam in the Mariana Islands for the first time. Factors indicating that this introduced mealybug has the potential to become a pest of economic importance for agriculture and horticulture on Guam are discussed.

Two new species of Selitrichodes (Hymenoptera: Eulophidae: Tetrastichinae) inducing galls on Casuarina (Casuarinaceae).

Two new species of gall-inducing wasps, Selitrichodes casuarinae Fisher & La Salle sp. n. and Selitrichodes utilis Fisher & La Salle sp. n., are described from Micronesia (Guam, Rota and Palau Islands) and Australia respectively. These species induce galls on Casuarina and can cause extensive damage to the trees. Their status as pest or beneficial species is discussed.

Application of game theory to the interface between militarization and environmental stewardship in the Mariana Islands.

We recently described threats to the terrestrial biological resources on the Mariana islands of Guam and Tinian resulting from the large-scale buildup of military operations. Attitudes that view these military buildup plans in a zero sum context whereby the positives of greater security and improved local economy can be attained only with corresponding negatives of environmental destruction are prevalent. We argue these attitudes oversimplify the complicated interactions between military operations and environmental damage. Here we discuss aspects of our case study that would benefit from application of game theory. Declines in ecosystem health are not unavoidable forms of collateral damage of peace-time military operations. We repeat, conservation of environmental resources is not ancillary to national security, it is integral.