Invasive species pose a serious threat to several of the United States’ native wildlife habitats and have a significant financial impact on agriculture, forestry, and recreation. An invasive species is defined as both non-native and damaging to the environment. Any living creature, from flora to fauna, including insects, birds, fish, and snakes, can become an invasive species. Examples of invasive species include introduced or naturalized animals and plants, feral species, and introduced diseases. Whether intentionally or accidentally released, invasive snakes can cause significant environmental damage. Continue reading to discover the seven invasive snakes in the United States and learn how destructive they can be.
Are Invasive Snakes Dangerous?
When an animal is introduced to an environment where it is not native, it might cause problems. The brown tree snake was unintentionally introduced to Guam shortly after World War II. Since then, it has wiped out Guam’s native birds, lizards, and other vital wildlife. Guam has lost ten of its twelve native forest birds, most of its bats, and approximately half of its native reptiles. Another example is the introduction of Burmese pythons in Florida, which has been connected to significant animal losses in Everglades National Park. Invasive species have the potential to extirpate native flora and fauna, reduce biodiversity, and compete for limited resources with native creatures.
Burmese Python
Burmese pythons are a threat to ecosystems as they are apex predators.
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The nonvenomous Burmese python (Python bivittatus) measures 10 to 16 feet long and weighs 100 to 200 pounds. It is native to Southeast Asia, and as a result of the pet trade, it has become an invasive species in Florida
The Burmese python is characterized by several brown streaks running down its back, bordered by black. There have been no known human fatalities caused by Burmese pythons in Florida. However, they pose a threat to local ecosystems. As apex predators, these pythons compete with local predator species. They prey on raccoons, opossums, bobcats, foxes, rabbits, birds, amphibians, and other reptiles.
Central African Rock Python
Central African rock pythons prey on mammals, reptiles, and birds.
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The Central African rock python (Python sebae) can weigh over 200 pounds, making it the largest snake in Africa. Average Central African rock pythons typically measure 10 to 13 feet long and weigh 44 to 121 pounds. They are native to Sub-Saharan Africa, where they inhabit open savannas and damp evergreen woods near freshwater bodies. As a species of the python family, African rock pythons lack venom and rely instead on their large bodies and powerful muscles to constrict prey.
Like the boa constrictor (Boa constrictor), the Central African rock python has begun to populate a small area of Florida. They are considered a potential threat to native mammalian, reptilian, and avian populations due to their presence in a small localized area of Miami-Dade County.
Brown Tree Snake
Brown tree snakes have no natural predators and not only target lizards, and small mammals, but also cause electrical damage owing to their habit of crawling on power lines
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The brown tree snake (Boiga irregularis), commonly referred to as the brown catsnake, is an arboreal colubrid snake native to Indonesia, Papua New Guinea, and Australia. This snake is notorious for being an invasive species in Guam, an unincorporated territory of the United States, where it has decimated native bird populations. This snake was initially found in Guam in the 1950s, having arrived on cargo ships from Papua New Guinea. They measure 3 to 6 feet long and weigh up to 5 pounds.
Because the brown tree snake does not have natural predators, it has spread rapidly. Not only have they decimated Guam’s wildlife, but brown tree snakes also crawl on power lines, resulting in costly power outages and electrical damage. Despite being aggressive, these snakes have weak neurotoxic venom and are not considered harmful to humans. However, human children are susceptible to serious medical conditions if bitten because of their low body mass. Even so, no fatalities of children have been reported.
Boa Constrictors
First spotted in Florida in the 1970s, boa constrictors can presently be found in Miami-Dade County.
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The boa constrictor, also known as the common boa, is a giant, nonvenomous, heavy-bodied snake commonly kept and bred in captivity. These snakes are native to tropical South America and several Caribbean Islands. Although not native to North America, boa constrictors have been found in Southern Florida since the 1970s. They are specifically known to settle and breed in and around the Charles Deering Estate in Miami-Dade County. Boas are also considered an invasive species in Puerto Rico.
Boa constrictors typically measure 6 to 10 feet long and weigh 22 to 33 pounds, with some individuals reaching up to 14 feet in length and weighing over 100 pounds. As an invasive species, they cause harm by competing with local predators for prey, decimating native wildlife, and spreading disease. They prey on a wide range of animals, including wildlife such as rodents, lizards, wild pigs, deer, and frogs, as well as domestic animals like dogs, cats, chickens, and rabbits.
Reticulated Python
Reticulated pythons are not protected in Florida owing to their status as an invasive species
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The reticulated python (Malayopython reticulatus) is a nonvenomous constrictor native to South and Southeast Asia. It is the world’s longest snake, with females measuring 10 to 20 feet long on average, and weighing 2 to 165 pounds. This species is classified as Least Concern on the IUCN Red List due to its widespread distribution.
Reticulated pythons have been occasionally found in Florida and Puerto Rico, but are not considered established invasive species in either location. As apex predators, they compete with local predator species for prey and simultaneously decimate the populations of the species they prey on. They are classified as a prohibited species, which allows them to be legally killed.
Banded Water Snakes
Banded water snakes are endemic to the Midwest and Southeast of the United States.
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The banded water snake (Nerodia fasciata), sometimes known as the Southern water snake, is a nonvenomous colubrid snake endemic to the Midwest and Southeastern United States. These snakes are typically 22-42 inches long and typically weigh less than one pound. Banded water snakes are becoming more common in California’s waterways, raising concerns among biologists at the University of California at Davis, with species being discovered in several regions near Sacramento and Long Beach. Banded water snakes are harmless to humans and thrive in suburban areas and human-disturbed ecosystems. They may, however, constitute a threat to native aquatic species such as frogs, snakes, and salamanders.
Green Anaconda
Green anacondas are known for being especially voracious and are capable of tucking away deer and even caimans
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The green anaconda (Eunectes murinus) is the world’s largest snake. The reticulated python, its relative, can grow to somewhat longer lengths, but the green anaconda’s massive girth makes it nearly twice as hefty. Females are significantly larger than males, and can be 15-18 feet long and weigh up to 550 pounds. Green anacondas are endemic to South America and can be found in swamps, marshes, and slow-moving streams across the Amazon and Orinoco basins. They are also found in Paraguay, Ecuador, Peru, Bolivia, and Guyana. Green anacondas consume wild pigs, capybara, caimans, deer, birds, turtles, and even jaguars to grow to their massive size. They are nonvenomous constrictors that belong to the boa family.
Although this snake is not known to reproduce naturally in Florida, individuals have been recorded in Alachua County and Miami-Dade County.
