A USGS scientist holds an invasive brown treesnake.
How is the USGS helping to prevent the spread of the brown treesnake?
Preventing the spread of the invasive brown treesnake (Boiga irregularis) is paramount. Without rigorous prevention, control (let alone removal) of an introduced reptile species is extremely difficult. In the case of the brown treesnake, prevention efforts include working to detect stowaway snakes before they leave the island, as well as extreme vigilance on islands where the snakes are most likely to invade.
USGS scientists develop and test tools to control invasive brown treesnakes, and study the snake’s impacts on Guam's ecosystems. The USGS also leads the multi-agency Brown Treesnake Rapid Response Team, which responds to invasive snake sightings throughout the Pacific and trains personnel from cooperating agencies.
The 2020 discovery of brown treesnakes on Cocos Island, a critical wildlife conservation area close to Guam, illustrates the risks that native wildlife face if the brown treesnake gets to any other snake-free islands. Getting ahead of the curve and implementing prevention efforts from the beginning are essential, before an invasive species becomes a problem.
Learn more: The Brown Treesnake
Related
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. In 2020, a population of Brown Treesnakes was discovered on Cocos Island, a small atoll of the southern shore of Guam, which represents the first instance of Brown...
Are there invasive reptiles other than Burmese pythons in the United States that people should be concerned about?
Free-ranging, non-native reptiles representing dozens of species from around the world escape or are illegally released in the United States every year. Many of these species fail to establish reproductive populations, but some are successful. Florida is a major transportation hub and has a climate that is suitable for many invasive species across taxonomic groups. Due to the suitable climate, and...
Can invasive pythons be eradicated?
The odds of eradicating an introduced population of reptiles once it has spread across a large area is very low – pointing to the importance of prevention, early detection, and rapid response. With the Burmese python now distributed across more than a thousand square miles of southern Florida, including all of Everglades National Park and across the southern coast to Rookery Bay National Estuarine...
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 the area. Pythons compete with native wildlife for food, which includes mammals, birds, and other reptiles. Severe declines in mammal populations throughout Everglades National Park have been linked to Burmese pythons, with the most severe declines in native...
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 unintentional introduction of the West Nile virus, chestnut blight, the South American...
Scientist holding brown treesnake
A USGS scientist holds an invasive brown treesnake.
A brown treesnake on frangipangi blossoms
A brown treesnake crawls on some frangipangi blossoms in Guam.
A brown treesnake crawls on some frangipangi blossoms in Guam.
Invasive brown treesnake
Brown treesnakes were a major contributor to the loss of nine of 11 native forest birds on Guam.
Brown treesnakes were a major contributor to the loss of nine of 11 native forest birds on Guam.
A brown treesnake in a Streptopelia bitorquata nest
A brown treesnake in a Streptopelia bitorquata (island collared dove) nest. Yona, Guam, 2009. Photo by James Stanford, USGS.
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.
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.
Related
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. In 2020, a population of Brown Treesnakes was discovered on Cocos Island, a small atoll of the southern shore of Guam, which represents the first instance of Brown...
Are there invasive reptiles other than Burmese pythons in the United States that people should be concerned about?
Free-ranging, non-native reptiles representing dozens of species from around the world escape or are illegally released in the United States every year. Many of these species fail to establish reproductive populations, but some are successful. Florida is a major transportation hub and has a climate that is suitable for many invasive species across taxonomic groups. Due to the suitable climate, and...
Can invasive pythons be eradicated?
The odds of eradicating an introduced population of reptiles once it has spread across a large area is very low – pointing to the importance of prevention, early detection, and rapid response. With the Burmese python now distributed across more than a thousand square miles of southern Florida, including all of Everglades National Park and across the southern coast to Rookery Bay National Estuarine...
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 the area. Pythons compete with native wildlife for food, which includes mammals, birds, and other reptiles. Severe declines in mammal populations throughout Everglades National Park have been linked to Burmese pythons, with the most severe declines in native...
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 unintentional introduction of the West Nile virus, chestnut blight, the South American...
Scientist holding brown treesnake
A USGS scientist holds an invasive brown treesnake.
A USGS scientist holds an invasive brown treesnake.
A brown treesnake on frangipangi blossoms
A brown treesnake crawls on some frangipangi blossoms in Guam.
A brown treesnake crawls on some frangipangi blossoms in Guam.
Invasive brown treesnake
Brown treesnakes were a major contributor to the loss of nine of 11 native forest birds on Guam.
Brown treesnakes were a major contributor to the loss of nine of 11 native forest birds on Guam.
A brown treesnake in a Streptopelia bitorquata nest
A brown treesnake in a Streptopelia bitorquata (island collared dove) nest. Yona, Guam, 2009. Photo by James Stanford, USGS.
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.
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.
Updated Date: March 14, 2025