Snake Owners See Furry Bias in Invasive Species Proposal

By LESLIE KAUFMAN
Published: January 8, 2011

Until recently, Jeremy Stone lived happily in Lindon, Utah, with his wife and four children, and an annex full of baby ball pythons and boa constrictors.

The Stone family shares a passion for slithering pets. Mr. Stone’s son Zach got his first boa, a specially bred variety that glows yellowish orange, as a reward for doing his summer chores at age 6.

But like many snake lovers, Mr. Stone has been seething at the American government since early last year, when it sought to ban the importation and interstate transportation of nine species of foreign snakes. The federal Fish and Wildlife Service said the animals, if freed, posed a serious risk to native ecosystems across the southern United States.

“It is a joke,” Mr. Stone said of the science behind the government’s decision.

Mr. Stone makes his living breeding snakes with genetic mutations, like albinism, that make them attractive to buyers. His animals, raised in captivity, pose no threat, he said. They would be picked off in an instant in the wild and would have no idea how to fend for themselves. And if they escaped from their warm annex in Lindon, he added, they would die from the cold.

When the Fish and Wildlife Service moved to ban trade in the snakes, which include boas and species of anacondas and pythons, it argued that they met the legal criteria for being both injurious and invasive. Invasive species — from Asian carp, which threaten the Great Lakes, to zebra mussels, which spread exponentially — are a serious environmental concern, one that is often not dealt with until a species has become firmly established. The Fish and Wildlife Service argues that in the case of the snakes, they are trying to get ahead of the problem.

But it is the first time the government has tried to list animals so widely held as pets. Roughly one million Americans are believed to own snakes of the types listed by the Interior Department, according to the United States Association of Reptile Keepers, and 31,000 were imported in 2008, the most recent year for which the government has data. Trade in these species is big business: more than $100 million annually. Those with rare colors can fetch upward of $75,000.

The move to ban the snakes has set off a swell of anger among aggrieved snake owners and breeders, who have the most to lose financially, as well as a smattering of academic herpetologists, zookeepers and representatives of international conservation groups. When the regulations came up for public review, they flooded the government with objections.

At the heart of their arguments is a critique of the emerging science of invasive species risk assessment. And their response has highlighted the challenges that the government faces as it increasingly moves to protect native flora and fauna not just from current invasive species but also from future threats.

The reptile keepers group, which claims 12,000 professional breeders and sellers as members, has filed formal objections with the Interior Department and is threatening a lawsuit based on what it says is the government’s poor scientific evidence.

Andrew Wyatt, the president of the association, argues that the government is now promoting a native-species-only agenda favored by environmental groups.

“This has implications for every animal interest out there, right down to family pets,” he said, adding that by such standards, “all amphibians are injurious and cats and hogs can’t be far behind.”

The battle goes back to 2006, when the South Florida Water Management District petitioned the Fish and Wildlife Service to list the snakes under the Lacey Act, which would make it a crime to transport them into the United States or across state borders.

Burmese pythons — some thought to be dumped by pet owners and some that escaped — were establishing themselves across the Everglades, where they were swallowing up everything from endangered Key Largo wood rats to alligators. The population has been expanding northward at roughly three and a half to six miles a year — Indy 500 speeds in reptilian terms.

In recent years, Florida officials had taken significant steps to limit ownership of invasive snakes within the state but still wanted more to be done. What was to protect the Everglades from a snake bought in Georgia and carried across state lines?

To ban the snakes under federal law, the government would have to show that they posed a threat to native plants, crops or animals. With very little science available about how reptiles that come from distant places like subtropical Asia and Africa might fare in America, the United States Geological Survey was asked to assess the risk.

The agency looked at many factors, including the damage in the Everglades. It also turned to a computer model to determine what parts of the country might have a hospitable climate for the species. The scientists looked at variables including mean monthly temperatures and rainfall at a wide range of elevations in the native habitats of the animals and matched them to patterns in the United States.

They estimated that suitable climates for the Burmese python in particular might include the 11 southernmost states from California to North Carolina. If global warming continued apace, the geological survey added, the snakes might even be at home in New York City by 2100. The national news media gave gleeful attention to the prospect of a snake invasion.

But soon after, biologists at the City University of New York did their own modeling, using more factors and different ones like precipitation during the wettest periods of the year, and came up with only Florida and South Texas as possible habitats for the snakes. Independent studies of snakes captured in the Everglades and taken north to Gainesville, Fla., and South Carolina found that most of the animals died when left outside in winter in those regions.

These findings were further bolstered when an unusual cold snap in the Everglades last January left a large number of Burmese pythons dead on canal banks and levees.

The studies have fired up the snake industry, which sees them as proof that the government is pursuing a hostile and unwarranted agenda. Mr. Stone, the breeder, said that the government regulations, which do not prevent breeding and owning but do prevent transportation across state lines, would ruin his business and thousands like it.

“The reptile industry would suffer a crushing blow, over something that does not make sense,” he said.

Dr. Elliott Jacobson, a professor of veterinary medicine at the University of Florida and a specialist in reptiles, also sees the government’s science as skewed. He loves snakes so much that he keeps 140 as pets and houses them in a guest cottage and in the bedrooms once occupied by his sons, now grown. But he said he suspected that the government was less sympathetic to his pets than to more cuddly creatures.

“The impact of feral cats, for example, on wildlife is much greater than what the Burmese pythons can do,” he said, noting that a cat eats much more than a snake of the same size.

But Thomas Strickland, assistant secretary for fish and wildlife and parks, said that the government was not going to back down and that it would approve the regulations by next summer. The science is solid, Mr. Strickland said, and the geological survey will soon publish a peer-reviewed answer to its critics.

Like other invasive species, snakes are a real and growing problem, he said. “You are not dealing with hamsters here,” he said. “I was down in the Everglades, and it took four people to hold a 19-foot Burmese python. These things wreak havoc.”

http://www.nytimes.com/2011/01/09/science/earth/09snakes.html?pagewanted=2&ref=us