If you have ever complained about flying on a budget airline, spare a thought for the Japanese snail Tornatellides boeningi. The only way for this laggard gastropod to rack up its air miles is to be eaten by a bird and excreted out the other end. And even though the stowaways are slathered in digestive fluids and feces, many of them survive, enabling them to spread their seed over a much larger area than their usual slow-lane pace would allow.

“This could help to explain why the snails are so widespread,” says biologist Shinichiro Wada of Tohoku University, who found that snails at one end of Hahajima Island (located south of the Japanese mainland) are as genetically similar to those from the opposite corner as to their neighbors.

Some snail species can survive trips through fishes’ digestive systems, but this is the first known to use avian airlines. Wada discovered the snails’ odd travel plans after finding undamaged shells in bird droppings. When he fed 174 live snails to Japanese white-eyes and brown-eared bulbuls, around 15 percent of them lived. “One of the snails even gave birth just after passing through the gut,” Wada says.

The snails probably survive because of their small size, averaging less than a tenth of an inch in length, and compact shells. Wada suspects that they shield themselves with mucus or seal the gap between their body and shell to prevent digestive fluids from seeping inside.