GIANT SNAKE PICTURES: Alien Species Invading U.S.?

[Kara Sundstrom]

GIANT SNAKE PICTURES: Alien Species Invading U.S.?

October 14, 2009--The world's heaviest snake, the green anaconda is one of nine huge alien snake species that may wreak havoc if they take hold in the United States, according to a U.S. Geological Survey (USGS) report released this week. (Read full story: "Alien Giant Snakes Threaten to Invade Up to 1/3 of U.S.")

The giant snake (pictured in the Peruvian Amazon) can reach lengths of 23 feet (7 meters) and weigh in at 550 pounds (227 kilograms). The olive-green reptiles would flourish in the Florida Peninsula and in southern Texas, regions that have climates similar to the anaconda's native South American habitat, the study authors say.

[Kara Sundstrom]

USGS scientists rated the nine snakes based on the risk of the reptiles becoming established in the U.S., which is most likely to happen in areas where pet snakes are commonly released into the wild. The green anaconda is among four species considered medium risks--the species is not popular as a pet, and fewer than 500 of the animals arrive in the U.S. each year from South America, according to the report. Though green anacondas have been found in the wild in Florida, there is no evidence they are breeding.

The five in the following gallery are the true giants, but the USGS scientists also studied four "look alike" species: the southern African python, DeSchauensee's anaconda, the Beni anaconda, and the yellow anaconda.

Kenneth Krysko, senior herpetologist at the Florida Museum of Natural History in Gainesville, called the report "extremely thorough." But it came as "no real surprise that giant constrictors can potentially be a threat to not only the wildlife here but to the humans," added Krysko, who was not involved in the report.

Green anacondas have not been known to attack humans, but their tastes vary widely, including fish, turtles, dogs, and tapirs. The snakes ambush prey from the water and constrict them with an immediately deadly, bone-crushing force. (Watch an anaconda hunt the world's largest rodent.)

--Christine Dell'Amore
—Photograph by Ingo Arndt, Minden Pictures, National Geographic Image Collection

http://news.nationalgeographic.com/news/2009/10/photogalleries/giant-invasive-snakes-florida-united-states/index.html

[Kara Sundstrom]

[Kara Sundstrom]

Brady Barr, host of the television show Dangerous Encounters, makes handling an 18-foot (5.5-meter) tiger reticulated python look easy as kids watch during the National Geographic Explorers Camp in Scottsdale, Arizona, on June 13, 2009.

But don't be fooled: The reticulated python, which has been recorded reaching up to 32 feet (10 meters) long, is known to attack and kill people in its native Southeast Asian habitat, making it the most deadly snake to humans, a new USGS report says.

There's also a medium risk that that the world's longest snake may establish itself in the U.S., the report says. The reptile, with its "beautiful network"--or reticulations--of earth-toned skin, is one of the most often imported pet snakes to the U.S., the report says. And South Florida's tropical habitat would be an ideal refuge for freed pythons.

"Humans here, we're not used to large snakes," said the Florida Museum of Natural History's Krysko. The usual advice for avoiding alligator attacks--for instance, staying away from tall grass along riverbanks--is futile against the alien snakes, he added.

"They can travel real far, real quick … the possibility of them taking a human is absolutely there."
—Photograph by Adrienne Heiltzer, Fairmont Scottsdale Resort via AP

[Kara Sundstrom]

Skip Snow of the National Park Service measures a captured Burmese python at the South Florida Research Center in Everglades National Park in an undated photograph.

The southern Asian snake's beauty and ease of handling has made it a mainstay in the pet trade, especially in Florida, where the species has been accidentally--and sometimes purposefully--released into the wild. There are now tens of thousands of pythons breeding in Florida, and some of them have been known to snack on rare wildlife, such as the Key Largo woodrat, the report says.

Florida Museum of Natural History's Krysko said officials haven't taken enough action to stop the snakes, in part because the reptiles are widespread throughout public and private lands.

"Burmese pythons don't see political boundaries," he said. "[We need to] remove every one of them and kill them all."
—Photograph courtesy Lori Oberhofer, National Park Service via United States Geological Survey

[Kara Sundstrom]

Africa's largest snake--the ill-tempered, 20-foot-long (6.1-meter-long) African rock python--has recently been discovered reproducing in Florida, the new USGS report says.

More dangerous than Burmese pythons--which are already breeding in Florida--the African pythons (above, an adult swallows an impala fawn) are "so mean, they come out of the egg striking," Florida Museum of Natural History's Krysko said in September. Partially for this reason, the snakes, native to sub-Saharan Africa, are not popular as pets in the United States.

But there's a high likelihood that the snakes could establish themselves if released into Florida's peninsula, southern Texas, and parts of Hawaii and Puerto Rico, the report says.
—Photograph by Beverly Joubert, National Geographic Image Collection

[Kara Sundstrom]

With its "dizzying" adaptability to a range of habitats, the boa constrictor could easily colonize much of the southern U.S., a new USGS report says.

There is a high likelihood that the Central and South American snake, which is commonly kept as a pet in the U.S., could establish itself if given the opportunity, according to the report. Escaped pet snakes have been found reproducing in Florida (pictured, a boa meanders through a county park in southeastern Miami), for example.

However, boa constrictors have never been known to attack humans, the authors said.
—Photograph courtesy Mike Rochford, University of Florida via United States Geological Survey

[Kara Sundstrom]

Python "Nightmare": New Giant Species Invading Florida
Christine Dell'Amore
National Geographic News
September 14, 2009

Already squeezed by the invasion of the giant Burmese python, Florida now faces what one scientist calls one of the U.S. state's "worst nightmares."

Africa's largest snake—the ill-tempered, 20-foot-long (6.1-meter-long) African rock python—is colonizing the U.S. state, new discoveries suggest.

Six African rock pythons have been found in Florida since 2002. More troubling, a pregnant female and two hatchlings have been found, which means the aggressive reptiles have set up house.

More dangerous than even Burmese pythons—which are known to eat alligators (alligator-python picture)—the African pythons are "so mean, they come out of the egg striking," said Kenneth Krysko, senior herpetologist at the Florida Museum of Natural History in Gainesville.

"This is just one vicious animal."

So far the giant snakes have been found only in a single square mile (2.6 square kilometers) of suburban area west of Miami. Pet breeders unprepared for the pythons' ferocity may have released them, Krysko said.

What's "really scary" is that the new invaders only have to cross the road to enter Everglades National Park, where Burmese pythons have already eaten thousands of native animals, he said.

With the addition of the rock python, Florida is now an established home-away-from-home for three large alien constrictors—including the Burmese species and the boa constrictor—according to wildlife biologist Robert Reed, who studies invasive reptiles for the U.S. Geological Survey in Fort Collins, Colorado.

http://news.nationalgeographic.com/news/2009/09/090911-pythons-florida-giant-snakes.html

[Kara Sundstrom]

Captured and killed in Florida, juvenile Burmese pythons (left), a young African rock python (center), and a larger African rock python lay coiled on a tray in a Unversity of Florida laboratory in late August 2009.

The African snakes typically grow to 20 feet (6 meters) long and have now colonized the U.S. state, as did the Burmese pythons before them, scientists said in September 2009.

Photograph courtesy Kenneth Krysko


The Florida python crisis will be covered in a future episode of Explorer on the U.S. National Geographic Channel. The National Geographic Channel is part-owned by the National Geographic Society, which owns National Geographic News.)

Pythons Threaten Mice and Men

In its native habitat, sub-Saharan Africa, the African rock python eats small mammals, antelope, warthog, herons, and other animals.

[Kara Sundstrom]

Updated September 5, 2006—Unfortunately for a 13-foot (4-meter) Burmese python in Florida's Everglades National Park, eating the enemy seems to have caused the voracious reptile to bust a gut—literally.

Wildlife researchers with the South Florida Natural Resources Center found the dead, headless python in October 2005 after it apparently tried to digest a 6-foot-long (2-meter-long) American alligator. The mostly intact dead gator was found sticking out of a hole in the midsection of the python, and wads of gator skin were found in the snake's gastrointestinal tract.

The gruesome discovery suggests that the python's feisty last meal might have been simply too much for it to handle.

An alternative theory will be put forth in a September 16 Explorer episode on the National Geographic Channel.

(National Geographic News is part of the National Geographic Society, which is part owner of the National Geographic Channel.)

An animated recreation of the python-alligator battle suggests that the python might have survived its massive meal but that a second gator came to the rescue and bit off the snake's head. The force of the tussle, the new theory says, is what caused the python to burst.

But even scientists associated with the show aren't so sure the new theory holds water.

Wayne King, reptile curator at the Florida Museum of Natural History in Gainesville, cites the relatively clean decapitation of the snake. "Alligators, they don't bite off a piece," he told McClatchey Newspapers. "They grab hold, then they roll and spin. If one grabs you by the arm, normally they wrench the arm off, or if they grab you by the buttocks, they'll rip away a chunk of meat."

Clashes between alligators and pythons have been on the rise in the Everglades for the past 20 years. Unwanted pet snakes dumped in the swamp have thrived, and the Asian reptile is now a major competitor in the alligator's native ecosystem. (See "Huge, Freed Pet Pythons Invade Florida Everglades.")

"Clearly if [pythons] can kill an alligator, they can kill other species," Frank Mazzotti, a University of Florida wildlife professor, told the Associated Press. "There had been some hope that alligators can control Burmese pythons. … This [event] indicates to me it's going to be an even draw."

—Victoria Gilman

[Kara Sundstrom]

In Florida the African snake might "eat almost any warm-blooded animal that is big enough to ingest," as the Burmese python does, USGS's Reed said.

"Dozens of species of native wildlife, from white-tailed deer to 6-foot [183-centimeter] alligators to birds, have been found in the digestive tracts of Burmese pythons in Florida," said Reed, who is also working with the Florida museum's Krysko on the Florida python problem.

Also like the Burmese python, the African snake is a constrictor. Lacking poison, it kills animals by encircling and literally squeezing the life out of them.

(Related: See a Burmese python digesting a pregnant sheep.)

Florida wildlife may not be the only creatures at risk. In Africa, rock pythons are known to have attacked humans, Krysko said.

Hidden in a Florida swamp, he added, the African python "could strike you and you wouldn't even know it was there."

Python + Python = Hybrid Supersnake?

African pythons have likely already made it into the Everglades, Krysko said. If so, it shouldn't be long before they encounter their Burmese cousins.

If the two python species mate, they may spawn a hybrid species, as has happened in captivity. And because of a biological phenomenon called hybrid vigor, there's an off chance the resulting snakes could be hardier, more powerful predators—assuming they're not sterile, as many hybrids are—USGS's Reed said.

"We can't rule out the possibility," Reed said, "that the introduction of genes from a different species might do something that would allow [the rock pythons] to be even more effective at persisting in Florida and perhaps expanding."

[Kara Sundstrom]

Worse Than the Burmese Python?

The rock python's expansion mirrors the Burmese snake's explosion for some Florida conservationists—and a chance to learn from past mistakes.

"The thing that scares me the most is that this could be another Burmese python," said Kristina Serbesoff-King, invasive species program manager for the nonprofit Nature Conservancy in Florida. (Read biologist Stuart Pimm's take on tackling the Florida python crisis.)

In a 1994 report the Florida Department of Environmental Protection sounded the alarm about the explosion of invasive species in the state, whose warmth and major international ports put it at particular risk.

The report specifically named the African rock python as a threat to pets, native wildlife, and small children. The advisory, however, predicted that in Florida the African snake would be unable to breed in the wild.

"Here we are, 15 years later, and that whole ounce-of-prevention story is so glaring," Serbesoff-King said.

"There's a real opportunity to [mount] an aggressive response" to get rid of the African rock python while the giant snake is still limited to a relatively small area, Serbesoff-King added.

One model, she said, may be the "python patrol" that the Nature Conservancy set up in the Florida Keys. After the Burmese python swam from the Everglades to the island chain and began munching rare Keys wildlife, the team started searching for and capturing the snakes to slow the species' spread.

The Florida museum's Krysko and USGS's Reed both agree that the African snake must be knocked out—and now.

The arrival of the Burmese python "was the biggest, [most] devastating problem that Florida ever could have imagined," Krysko said.

"Now we have a worse one."