Invasive species present in the Indo-Pacific region cause significant economic and ecological damage to Department of Defense installations through rapid spread and aggressive feeding on palm trees. Infestations of invasive species threaten critical infrastructure and natural vegetation used for cover and concealment, degrading training environments and increasing maintenance costs.  

Despite the widespread use of pheromone-baited panel or barrel traps, the probability of detecting invasive species when present remains poorly quantified, limiting the effectiveness of current monitoring efforts. 

The objective of this project is to quantify and compare the effectiveness of trap and eDNA-based detection for Coconut Rhinoceros Beetle (CRB; Oryctesrhinoceros), a high profile and impactful pest, across different environmental contexts. This research will inform sampling effort requirements and support resource managers in developing efficient monitoring programs for early invasion detection. 

This work leverages data from extensive monitoring of CRB and extends ongoing efforts to assess the feasibility of eDNA detection. For the first objective, CRB occupancy and detection based on data from the Hawaii Coconut Rhinoceros Beetle Response will be estimated, which has operated an extensive trapping network since 2013. Recent extensions of occupancy models will be used that can incorporate multiple survey methods and account for spatial gradients in capture rates. For the second objective, eDNA will be collected from palm trees at sites with low CRB abundance and analyze samples to estimate the probability of detecting CRB. For the third objective, information on detection probabilities from traps and eDNA will be incorporated to design efficient and effective sampling methods for incipient populations. The project team will also assess confidence in absence based on data from military and port locations where CRB is not known to be present. 

Ongoing spread of CRB across the Indo-Pacific is a major concern, and rapid detection is critical for containment and treatment. The comparison of survey efficacy will enable managers to choose the tools most likely to yield a detection, while the analysis of how trap placement affects captures will help people situate traps within their focal areas. This work will thereby directly inform the design and implementation of programs in Hawaii and the Indo-Pacific Region. (Anticipated Project Completion - 2027)