Invasive black and white tegu lizards (Salvator merianae). USGS is working on development of tools for the detection and capture of invasive reptiles in Florida.
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 other factors, Florida has the world’s largest number of established, non-indigenous reptile and amphibian species. Several species of reptile are of high concern, including:
- Argentine black and white tegu (Salvator merianae) - established in several locations throughout Florida and Georgia. These lizards are dietary generalists but are known to feed on eggs of ground-nesting animals. The establishment of black and white tegus is a concern for many threatened or endangered species in the Everglades National Park, such as the American Crocodile (Crocodylus acutus) and Black Rail (Laterallus jamaicensis).
- Gold tegu (Tepinambis teguixin) are established in Florida and Georgia, and ecologically similar to the Argentine black and white tegu.
- Green iguana (Iguana iguana) populations are established in Hawaii, Florida, Texas, Puerto Rico, and the U.S. Virgin Islands.
- The Red-eared slider turtle (Trachemys scripta elegans) was introduced to western states from its native range in the eastern U.S.
Disposal or release of non-native animals into the wild can do great environmental harm. Unwanted animals should be safely rehomed or presented to a Fish and Wildlife agency.
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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 places where it is not native. For example, the Brown Treesnake was introduced to...
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...
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Invasive black and white tegu lizards (Salvator merianae). USGS is working on development of tools for the detection and capture of invasive reptiles in Florida.
Alejandro Grajal-Puche shows an Argentine black-and-white tegu (Tupinambis merianae) with a radio-transmitter backpack over its pelvis. USGS photo.
Alejandro Grajal-Puche shows an Argentine black-and-white tegu (Tupinambis merianae) with a radio-transmitter backpack over its pelvis. USGS photo.
Adam Sepulveda, research zoologist at the USGS Northern Rocky Mountain Science Center, explains a scientists at NOROCK are using environmental DNA — the identification of species through biological information they leave behind in their habitat — to detect invasive species and how this method could change the way scientists find evidence of biodiversity in
Adam Sepulveda, research zoologist at the USGS Northern Rocky Mountain Science Center, explains a scientists at NOROCK are using environmental DNA — the identification of species through biological information they leave behind in their habitat — to detect invasive species and how this method could change the way scientists find evidence of biodiversity in
Over the last several decades, non-native species have continued to invade sensitive ecosystems in the United States. Two high-profile species, Asian carp in the Midwest and Burmese pythons in the Everglades, are the focus of much attention by decision makers, the public and the media.
Over the last several decades, non-native species have continued to invade sensitive ecosystems in the United States. Two high-profile species, Asian carp in the Midwest and Burmese pythons in the Everglades, are the focus of much attention by decision makers, the public and the media.
As part of a USGS radiotelemetry study, this tegu carried a transmitter backpack for a year to provide information on how tegus are moving through Florida landscapes
As part of a USGS radiotelemetry study, this tegu carried a transmitter backpack for a year to provide information on how tegus are moving through Florida landscapes
Big Ol‘ Gal
This is an image of a brown treesnake in a tree in Guam, taken in 2009.
This is an image of a brown treesnake in a tree in Guam, taken in 2009.
Right now in Florida, non-native, giant constrictor snakes—pythons, anacondas, and the boa constrictor—are being found in the wild, and two species have established several breeding populations. The snakes pose a considerable resource management challenge for agencies charged with preserving native ecosystems and species.
Right now in Florida, non-native, giant constrictor snakes—pythons, anacondas, and the boa constrictor—are being found in the wild, and two species have established several breeding populations. The snakes pose a considerable resource management challenge for agencies charged with preserving native ecosystems and species.
U.S. Geological Survey invasive species research—Improving detection, awareness, decision support, and control
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- FAQ
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 places where it is not native. For example, the Brown Treesnake was introduced to...
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...
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...
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...
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...
- Multimedia
Invasive black and white tegu lizards (Salvator merianae).Invasive black and white tegu lizards (Salvator merianae).
Invasive black and white tegu lizards (Salvator merianae). USGS is working on development of tools for the detection and capture of invasive reptiles in Florida.
Invasive black and white tegu lizards (Salvator merianae). USGS is working on development of tools for the detection and capture of invasive reptiles in Florida.
Alejandro Grajal-Puche shows an Argentine black-and-white teguAlejandro Grajal-Puche shows an Argentine black-and-white teguAlejandro Grajal-Puche shows an Argentine black-and-white tegu (Tupinambis merianae) with a radio-transmitter backpack over its pelvis. USGS photo.
Alejandro Grajal-Puche shows an Argentine black-and-white tegu (Tupinambis merianae) with a radio-transmitter backpack over its pelvis. USGS photo.
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As part of a USGS radiotelemetry study, this tegu carried a transmitter backpack for a year to provide information on how tegus are moving through Florida landscapes
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Right now in Florida, non-native, giant constrictor snakes—pythons, anacondas, and the boa constrictor—are being found in the wild, and two species have established several breeding populations. The snakes pose a considerable resource management challenge for agencies charged with preserving native ecosystems and species.
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Invasive species research within the U.S. Geological Survey’s Ecosystems Mission Area focuses on invasive organisms throughout the United States. U.S. Geological Survey scientists work with partners in the Department of the Interior, other Federal, State and Territorial agencies, Tribes, industry, and agriculture to provide the information needed to help solve problems posed by these invaders. KeyAuthorsEarl Campbell, Cindy Kolar Tam, Suzanna C. SoileauInvasive Species Science Branch: research and management tools for controlling invasive species
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