• A baby African rock python wraps itself around a tree in Koedoesdraai, South Africa. (Photo: Hannes Steyn)

When two young boys from New Brunswick were found dead early Monday morning, reportedly asphyxiated by an African rock python that had escaped from its cage, the world was shocked. Snake attacks on humans are extremely rare, experts agreed. Canadian Geographic asked Leslie Anthony, author of Snakebit: Confessions of a Herpetologist, about the dangers of keeping pythons as pets.

Canadian Geographic: Why is this such an unusual incident?

Leslie Anthony: Despite the huge numbers of large snakes kept as pets —even by careless people — fatal incidents are vanishingly small, on par with being struck by lightning when compared to deaths caused by dogs etc. Snakes don't recognize humans as food and so extraneous circumstances of fear, threat or food-scent generally have to be operative. That being said, I know from personal experience that if you're trying to pry a python off someone, it has no qualms about wrapping you as well; we obviously don't have all the facts on this one yet but that is one possible scenario.

Can Geo: Should pythons be accepted as pets?

LA: Large snakes have no place as pets — and I use that word sensu lato, since these things are in theory and practice more like living display items than actual pets. If certain jurisdictions do allow them to be kept privately, they should certainly be registered. Unfortunately — and this is a very important point that no one seems to have made — the danger posed by snakes is part of what drives many people to own them.

Can Geo: How common are pythons as pets?

LA: Extremely common. At one point the U.S. was importing upwards of 60,000 Burmese pythons per year. That's dropped way off as most now come from domestic captive breeding facilities. But because of improved husbandry and cross-breeding for "designer" snakes with different colour traits — albino, xanthic, piebald etc. — the overall numbers sold on the continent each year are up. The pet trade in pythons is behind the huge invasive species problem of Burmese pythons in the Florida Everglades, where the feral, breeding population is now thought to exceed 100,000.

Can Geo: How do pet snakes behave different than wild ones?

LA: Snakes that are used to being handled by humans may not startle as easily, but will certainly startle under the right circumstances. Snakes that bite when they feel threatened will still bite — though the threshold of feeling threatened might have moved.

Can Geo: How should snake owners safely keep their pets?

LA: Follow professional guidelines and best practices and don't think you can figure these out for yourself — especially if you're inexperienced. Snakes — all snakes, large and small — are the Houdinis of the animal world. Getting in and out of improbable spaces is their evolutionary thing. When it comes to escaping enclosures of any kind they are consummate trial-and-error problem solvers whose shape-shifting abilities and relative strength are much greater than you think.