Scientists warn of homing pythons: Experts discover giant snakes ‘have compass instinct’

New study has implications for authorities removing snakes in Florida – only to see them come straight back

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The Independent Online

Giant Burmese pythons have “homing” instincts allowing them to accurately navigate over large distances, scientists have discovered.

The enormous snakes are capable growing up to lengths of more than 17 feet (5m) and swallowing large deer and alligators, causing serious ecological issues in Florida’s Everglades national park.

With their camouflaged tan colouring and powerful, heavy builds, the reptiles can be difficult for pest control authorities to track down and capture – yet new research has emerged suggesting this may be only half the battle.

According to a study published in the Royal Society journal Biology Letters, pythons captured in the Everglades and moved to other suitable habitats were able to navigate over at least 23 miles back to their homes.

Researchers captured 12 snakes and fitted GPS tracking devices under their skin. Six were then released in the same place as control subjects, while the other six were relocated between 13 and 23 miles away.

Observing and recording the pythons’ movements afterwards, scientists found that the re-homed snakes headed straight back for their capture locations, moving both quicker and more directly than the control specimens.

A python strangles and ultimately eats a crocodile after an epic duel earlier this month at Lake Moondarra in north-western Queensland, Australia

“We were very surprised,” lead author Shannon Pittman told BBC News.

“We anticipated the pythons would develop new home ranges where they were released. We didn't expect them to orient back to their capture locations.

“This is evidence that Burmese pythons are capable of homing on a scale previously undocumented in any snake species.”

“The snakes maintained their oriented movement over the course of a relatively long time, between 94 and 296 days,” said Kristen Hart, a study co-author. “This indicates that not only do pythons keep their long-term movement goal in mind, but also that they were highly motivated to get back home.”

A 13 foot python recently strangled a security guard to death on the holiday island of Bali, Indonesia

Experts said the research implied other snake species are likely to also have previously-undiscovered homing instincts.

Other reptiles, like sea turtles, have previously been shown to have a magnetic “map” sense that allows them to determine their position in relation to home.

The study said pythons must also have a “compass” sense guiding their homing movement, which could be aided by the stars, magnetic fields, olfactory (smell) or polarised light cues.

The giant snakes have become one of the leading predators in the Everglades after establishing themselves several decades ago, and have been blamed for a massive drop in mammal populations.

“Understanding navigation in invasive species improves the ability to control populations and limit dispersion,” said Ms Hart.