What is the brown treesnake?

The brown treesnake is native to parts of Indonesia, the Solomon Islands, New Guinea, and Australia. The snake was first sighted on the island of Guam in the 1950s, probably after stowing away on cargo ships coming from New Guinea.

The snakes feed on lizards, birds, small mammals, and eggs. Since the treesnake has no natural predators or other controls on Guam, it multiplied rapidly and has virtually wiped out Guam’s native forest birds. The snakes also crawl on electrical lines and cause expensive power outages and electrical damage.

Brown treesnakes are mildly venomous. While the snakes are not considered dangerous to an adult human and no known deaths have occurred, young children can have reactions to tree snake bites.

While many techniques have been discussed to eliminate the brown treesnake in Guam, there is no known way to remove them entirely.  The best management strategy is to keep them from becoming established at new locations while continuing to do research on tools such as improved traps, fumigants, toxicants, and attractants; and on control options such as parasites and viruses.

Related Content

Filter Total Items: 7

Are there invasive reptiles other than Burmese pythons in the United States that people should be concerned about?

Free-ranging snakes representing dozens of species from around the world are discovered in the United States in any given year, usually as a result of escapees or illegal releases, but most of these have not established reproductive populations.

Florida is a major transportation hub and has a climate that’s suitable

...Read Full Answer

How have invasive pythons impacted Florida ecosystems?

Non-native Burmese pythons have established a breeding population in South Florida and are one of the most concerning invasive species in Everglades National Park. Pythons compete with native wildlife for food, which includes mammals, birds, and other reptiles. Severe mammal declines in Everglades National Park have been

...Read Full Answer

Are large constrictor snakes such as Burmese pythons able to kill people? What is the risk?  Would this be in the wild, or in backyards?

Human fatalities from non-venomous snakes are very rare, probably averaging one or two per year worldwide. All known constrictor-snake fatalities in the United States are from captive snakes; these are split between deaths of snake owners who were purposefully interacting with their pet and deaths of small children or

...Read Full Answer

Can invasive pythons be eradicated?

The odds of eradicating an introduced population of reptiles once it has spread across a large area are very low, pointing to the importance of prevention, early detection and rapid response.  And with the Burmese python now distributed across more than a thousand square miles of southern Florida, including all of

...Read Full Answer

How is the USGS helping prevent the spread of the brown treesnake?

Preventing the spread of the invasive brown treesnake is paramount. It is much cheaper than intervention once a snake population is established.

Without rigorous prevention, it is extremely difficult to control (let alone remove) an introduced reptile species. In the case of the brown treesnake, prevention efforts

...Read Full Answer

What is an invasive species and why are they a problem?

An invasive species is an introduced, nonnative organism (disease, parasite, plant, or animal) that begins to spread or expand its range from the site of its original introduction and that has the potential to cause harm to the environment, the economy, or to human health.

A few well-known examples include the

...Read Full Answer

Are invasive snakes dangerous?

Free-ranging snakes representing dozens of species from around the world are discovered in the United States in any given year, usually as a result of escapees or releases from the pet trade, but most of these don't appear to have established a reproductive population.

Any animal can be problematic when released in

...Read Full Answer
Filter Total Items: 2
Date published: March 3, 2016

Brown Treesnake Rapid Response Team Deployed to Saipan after Two Snake Sightings

Two recent reports of two brown treesnakes on Saipan is prompting federal and state officials to urge citizens of Hawaii, Guam and other Pacific Islands to report any sightings of these invasive snakes to authorities. Snakes can be reported by calling (671) 777-HISS or (670) 28-SNAKE.

Date published: November 7, 1997

Snake Barrier On Rota is Important Step Toward Preventing Future Spread of Brown Tree Snake

A new way to prevent brown tree snakes from invading was unveiled yesterday by scientists working for the U.S. Department of the Interior’s U.S. Geological Survey and Ohio State University.

Filter Total Items: 9
A brown treesnake on frangipangi blossoms, by Bjorn Lardner, USGS.
2011 (approx.)

A brown treesnake crawls on some frangipangi blossoms in Guam. 

A brown treesnake in a Streptopelia bitorquata (island collared dove) nest. Yona, Guam, 2009.
2009 (approx.)

A brown treesnake in a Streptopelia bitorquata (island collared dove) nest. Yona, Guam, 2009. Photo by James Stanford, USGS.

A brown treesnake in a tree in Guam. Photo by Bob Reed, USGS, 2009.
2009 (approx.)

A brown treesnake in a tree in Guam. Photo by Bob Reed, USGS, 2009.

A brown treesnake in a tree in Guam. Photo by Bob Reed, USGS.
2009 (approx.)

This is an image of a brown treesnake in a tree in Guam, taken in 2009.