Shortly after World War II, and before 1952, the brown tree snake was accidentally transported from its native range in the South Pacific to Guam, probably as a stowaway in ship cargo or by crawling into the landing gear of Guam-bound aircraft. As a result of abundant prey resources on Guam and the absence of natural predators apart from the native Mariana monitor and feral pigs, brown tree snake populations reached unprecedented numbers. Snakes caused the extirpation of most of the native forest vertebrate species; thousands of power outages affecting private, commercial, and military activities; widespread loss of people's pets; and considerable emotional trauma to residents and visitors alike when snakes invaded human habitats with the potential for envenomation of small children. Since Guam is a major transportation hub in the Pacific, numerous opportunities exist for the brown tree snakes on Guam to be introduced accidentally to other Pacific islands as passive stowaways in ship and air traffic from Guam. To minimize this threat, trained dogs are used to search, locate, and remove brown tree snakes before outbound military and commercial cargo and transportation vessels leave the island. Numerous sightings of this species have been reported on other islands including Wake Island, Tinian, Rota, Okinawa, Diego Garcia, Hawaii, and even Texas in the continental United States. Hawaii is especially at heavy risk from the snake, as direct military flights between Guam and Hawaii are allowed and brown tree snakes are regularly intercepted at landing areas. A successful introduction could pose an immense threat to the already highly threatened endemic birds of the islands. An incipient population was thought to be established on Saipan after sightings around the port; however, after 20 years without a sighting it appears that Saipan's biosecurity inspections have worked and the island is free of them. Acetaminophen has been used to help eradicate the snake on Guam.
