A Burmese python killed in Florida

Wow. Biologists working in the Florida Everglades have confirmed what they suspected all along — that Burmese pythons are consuming mammals at a startling rate. To see just how startling, read on. From the Associated Press:

MIAMI _ While Burmese pythons boomed in the Everglades, populations of key native animals headed in the opposite direction — their numbers crashing to near-zero in the case of bite-sized creatures such as raccoons, opossums and marsh rabbits.

Those are the findings of a sobering study published Monday, the first by scientists to assess the impact the giant constrictors have had on the complex food web of the Everglades. A word sums it up: carnage.

Scientists have firmly established what pythons eat, pulling the remains of just about everything that walks, crawls or flies in the Everglades from the bellies of captured snakes over the last decade. But just how much a snake population of unknown size has been eating has largely been a guess, at least until now.

According to the study published in the science journal Proceedings of the National Academy of Science, the probable answer is, once again, just about everything.

“When we actually did the calculations, we were astonished by the magnitude of the declines,” said Michael Dorcas, a biology professor at Davidson College in North Carolina and the study’s lead author.

The peer-reviewed study, based on nocturnal field surveys conducted before and after the python invasion, suggests a collapse of the park’s mid-sized mammal populations since the mid-1990s and points to the exotic snake as prime suspect.

Raccoons — once so abundant that park managers had to post signs warning campers to safeguard food from roaming hoards of the wily thieves — dropped 99.3 percent. Opossum sightings fell 98.9 percent. Observations of bobcats, foxes and deer also all fell precipitously, though researchers believe those declines could be less from snakes eating them and more from the indirect effect of pythons reducing the amount of prey to go around.

And marsh rabbits, small brown bunnies frequently seen foraging along roads in the park’s pre-python past, didn’t appear at all during the surveys.

Frank Mazzotti, a wildlife ecology professor at the University of Florida, likened the study to a grand jury investigation — a damning initial finding that needs more research to refine and confirm.

“We examined all the evidence and there is enough to indict pythons but we haven’t gone to trial yet,” said Mazzotti, one of 11 university and federal government researchers who co-authored the study.

Other factors, such as changes in Everglades water levels that can affect the food chain at microscopic levels may have contributed to the mammal decline as well, he said.

Still, the Obama administration pointed to the findings as more justification for the decision earlier this month to ban the import and interstate sale of Burmese pythons, two types of African rock pythons and yellow anacondas. The decision to declare them “injurious species” had been criticized by reptile breeders and collectors, as well as some Republican lawmakers who contend the measure would kill jobs in the cottage industry of constrictor breeding.

The study suggests a strong link between the rise of the snake and the fall of the bunnies and other mammals, finding little support for other possible causes. Between 2000 and 2010, a period when python captures soared from two to nearly 400 a year, no diseases swept the mammal population and there were no big losses of habitat or other major environmental changes that might explain the declines, the study found.

Besides the coincidental timing, researchers also found a pattern across the landscape, with the greatest losses in the southern portion of the park in and around Flamingo, where the python infestation has been heaviest. Mammal populations are strong on the park’s fringes or in adjacent areas.

“Our data are consistent in any number of ways with python as the primary reason or maybe the only reason, either directly or indirectly,” said Dorcas, author of the book “Invasive Pythons in the United States.”

Scientists can only guess at the population of Burmese pythons in the vast expanse of the Everglades, estimating the number in the tens of thousands, even after a record freeze in 2010 that may have knocked the population back by half or more. A month after the cold snap, biologists captured a 16-foot female in a nest with more than 100 eggs.

To assess the impact of pythons on wildlife, researchers counted live animals and road kill during sunset-to-sunrise surveys from 2003 to 2011, driving slowly along the main roads in Everglades National Park and counting the most common and easy-to-spot animals. They conducted 313 surveys, covering some 39,000 miles, as well as 26 surveys at sites along the park border and in adjacent federally protected lands. They compared the results to similar surveys conducted in 1996, before pythons had spread across much of the Everglades.

The changes in 15 years were startling. Before pythons, a raccoon would show up every 30 miles or so, according to the study. In more recent years, researchers would go nights without seeing a single one.

The systematic surveys, called transects, don’t necessarily mean that the animals have disappeared completely. But the results are a measure of “relative abundance” and that’s considered a good indicator of trends across the entire system, Dorcas said.

The surveys, he said, also are supported by numerous anecdotal reports from rangers, naturalists, photographers and others who have seen sharp drops in mammal numbers. The study notes that that last visitor to report a nuisance raccoon did so in 2005.

“Pythons are wreaking havoc on one of America’s most beautiful, treasured and naturally bountiful ecosystems,” said Marcia McNutt, director of the U.S. Geological Survey, whose scientists contributed to the study. “Right now, the only hope to halt further python invasion into new areas is swift, decisive and deliberate human action.”

Snake hunter Dave Leivman with 9-foot python (AP photo)

Faced with further damage to native wildlife species in Everglades National Park, the U.S. government has decided to crack down on the importation of Burmese pythons and three other large constrictor species. From the Associated Press:

A Burmese python killed in Florida

If a Washington congressman gets his way, it could become illegal to import several species of pythons and anacondas into the United States. From the Associated Press:

WASHINGTON _ As one of Congress’ top experts on spending issues, Washington state Rep. Norm Dicks keeps an eye on the public purse, and he says that Burmese pythons just cost taxpayers way too much money.

As the snakes multiply and spread, Dicks says, the federal government must spend millions of dollars each year to try to control them. Moreover, he says, the giant, fast-growing snakes jeopardize public safety and threaten the government’s huge investment in restoring Florida’s Everglades.

Dicks, the top Democrat on the House Appropriations Committee, has had enough: He says it’s time to make sure that no more of the snakes, which can exceed lengths of 20 feet, are allowed to enter the United States or move across state lines.

To that end, Dicks wants President Barack Obama’s administration to act quickly to finalize a proposed rule that would stop all imports and interstate transport of Burmese pythons and eight other types of constrictors.

Zoos would not be affected. Under the proposed rule, which has won the backing of the Humane Society of the United States, exemptions could be granted for “scientific, medical, educational or zoological purposes.”

While many of the snakes are popular as pets, Dicks said the pythons are “causing damage and devastation” and must be banned.

“They’re killing a lot of other species, and they’re dangerous,” Dicks said in an interview.

Snake traders say that a ban would put them out of business. The proposed rule _ which also is opposed by the U.S. Association of Reptile Keepers _ has bogged down as some Republicans, including Rep. Darrell Issa of California, have sympathized with the snake importers, citing the proposed rule as another example of job-killing policies promoted by the Obama administration.

The snakes, estimated in the tens of thousands in Florida, have long been a source of trouble, eating alligators, porcupines and other animals. In 2009, a pet python strangled a 2-year-old girl in the state. And in October, workers captured a 16-foot python that had gobbled up a 76-pound deer.

While some Florida lawmakers have worked for years to try to get the snakes banned, key congressional appropriators now are promoting the cause.

Teaming up with Republican Rep. Bill Young of Florida, another senior member of the House Appropriations Committee, Dicks wrote a letter to the president shortly before Congress’ holiday break, saying the federal government “simply cannot afford additional spending in the billions to control invasive species.”

They said the government already has spent billions on restoring the Everglades and complained that the snakes have now become the dominant predator and threaten the region’s sensitive ecosystem.

Noting the “enormous reproductive potential” of the snakes, the congressmen said, “This problem will continue to cost taxpayers millions of dollars annually” if it’s not addressed.

“We can also help prevent these large and powerful snakes from colonizing other southern regions of the nation where climate conditions would allow these reptiles to survive and thrive,” Dicks and Young wrote in their letter to Obama.

One study by the federal government found that if global temperatures continue to rise, pythons would be established in roughly one-third of the country by 2100, including in Washington state, Oregon, California, Colorado, Texas, Illinois, Indiana, Ohio, New York, New Jersey, Pennsylvania, Maryland and Delaware.

David Barker, a herpetologist and founder of a business that specializes in the research and propagation of pythons and boas, told the House Committee on Oversight and Government Reform in September that genetic testing indicates that the pythons established themselves in Florida sometime before 1994. Most likely, he said, it happened after the accidental release of captive-bred babies from a reptile distributor’s facility during Hurricane Andrew in 1992.

In 2009, Sen. Bill Nelson and Rep. Kendrick Meek, both Florida Democrats, introduced a bill that would have banned the snakes and stopped their movement across state lines by having the government declare them as “injurious wildlife” under an administrative process known as the Lacey Act.

After the legislative effort failed, Interior Secretary Ken Salazar joined the effort in 2010, backing a proposed rule by the U.S. Fish and Wildlife Service that would ban imports and interstate transport of the python and eight other snakes: the boa constrictor, the northern African python, the southern African python, the reticulated python, the green anaconda, the yellow anaconda, the Beni or Bolivian anaconda, and Deschauensee’s anaconda.

Salazar said that government officials face “an uphill battle” in trying to control the population of the snakes in ecosystems such as the Everglades, which lacks natural predators. With so many pythons on the loose, some have jokingly suggested changing the name to the “Neverglades.”

Herpetologist Barker said the snakes have become big business in the United States. According to his statistics, the number of households owning a reptile grew from 2.8 million to 4.7 million from 1994 to 1998, an increase of 68 percent. That compares with a 35 percent increase during the same period in households owning any kind of pet, he said.

Barker called the plan “misguided regulation” and predicted that it would result in industry losses of up to $1.2 billion over 10 years. He said that the federal government is overstating the threat caused by the snakes and that the issue should be left to the states.

“In short, if this rule goes into effect, it will destroy my life’s work and investments for no rational reason,” Barker said.

Dicks said the main opposition is coming from snake importers and that it shouldn’t be a reason to hold up the new rule any longer.

“I just think that’s ridiculous,” he said.

Wash. Dept. of Fish & Game photo

Bounty-collecting Louisiana residents have killed three-quarters of a million nutria in the past two years, yet apparently they haven’t put a dent in the rodents’ statewide population. That’s a shame, because the imported critters are wreaking havoc on the Bayou State’s ecosystem.

From the Associated Press:

HOUMA, La. (AP) — Officials say the annual Louisiana hunt for wetland-munching nutria brought in just over 338,000 tails worth $1.6 million.

The Coastwide Nutria Program reports that Plaquemines Parish hunters turned in the most tails, with just over 80,000, followed by Terrebonne Parish hunters who killed just over 65,000 nutria.

State wildlife biologist Edmond Mouton told The Courier that the numbers didn’t match last year’s record-setting 445,533. Mouton said higher water levels last year allowed hunters access to more nutria habitat and bigger catches.

Originally imported from South America to be farmed for fur, the oversized water-loving rodent soon escaped and wreaked havoc on wetlands. Nutria eat the roots of erosion-stopping marsh plants and also damage banks and levees by burrowing in.

Millions of dollars have been paid in bounties, but the nutria problem persists. Next time folks start arguing for coyote bounties in West Virginia, they should consider this.

Yes, nutria are quite a bit more prolific than coyotes, but coyotes have a peculiar reproductive trait that makes them hard to eradicate. When the coyote population drops, females start cranking out more pups. For that reason alone, it’s difficult to see how a bounty system would help much with the state’s coyote problem.