Control of the brown tree snake (Boiga irregularis) on Guam is a priority for the Department of Defense. Interdiction and control efforts to date have been significant and with the massive ongoing realignment of military personnel and infrastructure across the Pacific, including a significant build-up on Guam, concerns are heightened even more about the potential to spread the brown tree snake to other Pacific Islands. Indeed, the 2009 National Defense Authorization Act directs the Secretary of Defense to establish a program to control and eradicate the brown tree snake population from military facilities in Guam and to ensure that military activities, including the transport of civilian and military personnel and equipment to and from Guam, do not contribute to the spread of these snakes.

Brown tree snake management encompasses a number of objectives that include interdiction, control, and eradication of incipient populations. Various control approaches and tools have been developed or are under development. For example, ESTCP is funding a demonstration project that is intended to evaluate the aerial application of acetaminophen-treated baits for the control of brown tree snakes. Success here would not only reduce control costs but also make interdiction more effective.

SERDP researchers are investigating new approaches to enable control of extant brown tree snake populations in proximity to military facilities and transport operations with relative cost-efficiency and effectiveness but minimal impacts to non-target organisms. SERDP efforts are developing an artificial bait to replace dead mice for field application via the aerial control technique, developing a bait based on gecko skin extracts for use with juvenile brown tree snakes, and investigating the use of parasites as a control measure for brown tree snakes.

Ultimately, brown tree snake control can’t be thought of in isolation. Control itself may result in unintended consequences that lead to new invasive species problems. In addition, the past impacts of the brown tree snake have resulted in ecological legacies whose long-term impacts are poorly understood. The loss of native bird species on Guam also resulted in the loss of potential pollinators for the native trees. Future research will be needed to understand the new dynamics of species interactions on Guam and what this means to the long-term ability of Guam’s ecosystems to maintain their ecological function and provide desired ecosystem services.