Facts About the Brown Tree Snake

By Lisa Miller; Updated April 24, 2017
Brown tree snakes are upsetting the natural balance in Guam.

Brown tree snakes are rear-fanged arboreal (tree-dwelling) snakes. These secretive nocturnal snakes can be found in a wide variety of habitats and are known for their adaptability.

Geography

The native range of brown tree snakes includes Indonesia, the Solomon Islands, northern coastal regions of Australia and New Guinea. After World War II the snake was also introduced to the island of Guam.

Identification

Brown tree snakes can be identified by their slender bodies and their light brown coloration. Occasionally the snake may appear olive-colored or have black speckling along its body. These snakes usually range between 3 and 6 feet in length, but may grow larger.

Diet

Small mammals, lizards, birds and eggs make up the brown tree snake's native diet. The snakes in Guam have also been known to eat bats and small domesticated animals.

Significance

Due to abundant food sources and few natural predators, brown tree snakes have become a detrimental invasive species in Guam. Many of the island's native vertebrate species have famously become extinct due to the number of snakes on the island.

Fun Fact

Dogs trained to detect the presence of brown tree snakes are used in cargo ships and airplanes to ensure that the snakes do not spread to other island nations with climates similar to Guam.