Description of the Brown Tree Snake

Description

• Juvenile brown tree snakes (Boiga irregularis) are 15 inches long, and adults may reach 10 feet in length. They are brown, olive green or yellow in color, with reddish bands. Brown tree snakes have a large head and vertical pupils in the eyes. The snake is also rear-fanged, with a mildly toxic venom.

Habitat

• The brown tree snake inhabits the eastern part of Indonesia, Australia, New Guinea, the Solomon Islands and other islands of the South Pacific. It is reported that they were accidentally introduced into Guam on cargo ships after World War II. They are arboreal and are generally found in trees or shrubs.

Habits

• The brown tree snake is nocturnal, coming out of the trees to hunt. It is also an aggressive species, and will strike readily if provoked. They kill their prey by envenomation and constriction, chewing their prey to permit the venom from their rear fangs to penetrate the skin.

Food

• Prey of the brown tree snake includes birds, lizards, eggs, rodents and other small mammals. They are found near cities and towns because rats and mice usually found there high numbers.

Environmental Damage

• The brown tree snake is responsible for significant damage after it was introduced onto the island of Guam. Because it had few natural enemies there, it proliferated, and is responsible for the extinction of half of the lizard species on the island, nine out of 12 bird species found there, and some species of native bats.

Control

• All cargo leaving Guam is inspected for brown tree snake stowaways, using specially trained dogs. Cargo coming into Hawaii is inspected as well. Cleanup efforts are under way to limit the congregation of rats and mice in the cities, and trapping efforts have been successful as well. It is unlikely that the brown tree snake will be completely eradicated in Guam, but these efforts should keep the population in check.