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.