Title: Invasive Species - Lizards, Treesnakes, and Burmese Pythons, Oh My!
By Amy A. Yackel Adams and Andrea F. Currylow
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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 the American island of Guam shortly after World War II; it has decimated the native birds, mammals and lizards of Guam, such that only a few small species remain. Guam has now lost 10 of its 12 native forest birds, most of its bats, and about half of its native lizards. The introduction of Burmese pythons into Florida have been linked to severe mammal declines in Everglades National Park.
None of these snakes pose more than minimal risk to human safety. Human fatalities from non-venomous snakes in the wild are very rare, probably only a few per year worldwide. All known fatalities in the United States are from captive snakes. Predatory attacks by invasive pythons are a possibility, though the rarity of such attacks suggests that they are highly unlikely.
Learn more: USGS Invasive Animals
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...
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...
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...
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...
In their native ranges, many python and boa species are often found living in suburban and urban areas. In Florida, Boa constrictors and Northern African pythons live in or adjacent to the Miami metropolitan area. As with alligators, the risk of attacks on humans in urban areas is very low.
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 infants in homes where a snake was kept captive as a pet. There have been no...
The Burmese python is now distributed across more than a thousand square miles of southern Florida from coast to coast. This includes Everglades National Park, Biscayne National Park, Crocodile Lake National Wildlife Refuge, Francis S. Taylor Wildlife Management Area, Big Cypress National Preserve, Fakahatchee Strand Preserve State Park, Florida Panther National Wildlife Refuge, Picayune Strand...
Title: Invasive Species - Lizards, Treesnakes, and Burmese Pythons, Oh My!
By Amy A. Yackel Adams and Andrea F. Currylow
Title: Invasive Species - Lizards, Treesnakes, and Burmese Pythons, Oh My!
By Amy A. Yackel Adams and Andrea F. Currylow
A USGS scientist holds an invasive brown treesnake.
A USGS scientist holds an invasive brown treesnake.
This 16 1/2-foot python, being removed from the wild by USGS and NPS personnel, was captured in a thicket in Everglades National Park in May 2012.
This 16 1/2-foot python, being removed from the wild by USGS and NPS personnel, was captured in a thicket in Everglades National Park in May 2012.
Big Ol‘ Gal
Fishing guide Camp Walker, Catalyst Charters, of Islamorada, Fla., took this photo of a Burmese python swimming in Florida Bay from the end of Twisty Channel toward End Key on Nov. 16, 2011.
Fishing guide Camp Walker, Catalyst Charters, of Islamorada, Fla., took this photo of a Burmese python swimming in Florida Bay from the end of Twisty Channel toward End Key on Nov. 16, 2011.
A brown treesnake crawls on some frangipangi blossoms in Guam.
A brown treesnake crawls on some frangipangi blossoms in Guam.
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.
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...
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...
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...
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...
In their native ranges, many python and boa species are often found living in suburban and urban areas. In Florida, Boa constrictors and Northern African pythons live in or adjacent to the Miami metropolitan area. As with alligators, the risk of attacks on humans in urban areas is very low.
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 infants in homes where a snake was kept captive as a pet. There have been no...
The Burmese python is now distributed across more than a thousand square miles of southern Florida from coast to coast. This includes Everglades National Park, Biscayne National Park, Crocodile Lake National Wildlife Refuge, Francis S. Taylor Wildlife Management Area, Big Cypress National Preserve, Fakahatchee Strand Preserve State Park, Florida Panther National Wildlife Refuge, Picayune Strand...
Title: Invasive Species - Lizards, Treesnakes, and Burmese Pythons, Oh My!
By Amy A. Yackel Adams and Andrea F. Currylow
Title: Invasive Species - Lizards, Treesnakes, and Burmese Pythons, Oh My!
By Amy A. Yackel Adams and Andrea F. Currylow
A USGS scientist holds an invasive brown treesnake.
A USGS scientist holds an invasive brown treesnake.
This 16 1/2-foot python, being removed from the wild by USGS and NPS personnel, was captured in a thicket in Everglades National Park in May 2012.
This 16 1/2-foot python, being removed from the wild by USGS and NPS personnel, was captured in a thicket in Everglades National Park in May 2012.
Big Ol‘ Gal
Fishing guide Camp Walker, Catalyst Charters, of Islamorada, Fla., took this photo of a Burmese python swimming in Florida Bay from the end of Twisty Channel toward End Key on Nov. 16, 2011.
Fishing guide Camp Walker, Catalyst Charters, of Islamorada, Fla., took this photo of a Burmese python swimming in Florida Bay from the end of Twisty Channel toward End Key on Nov. 16, 2011.
A brown treesnake crawls on some frangipangi blossoms in Guam.
A brown treesnake crawls on some frangipangi blossoms in Guam.
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.