Invasive species are nothing new to Australia.  From the cane toad to the artichoke thistle, Oz is paying the price for guests brought along with European colonization of the Great Southern Land.  In Japan, an invasive species isn’t just changing the landscape – it’s threatening to takes some fingers and toes along with it.

American Snapping Turtles were brought over to as pets from the 1960s.  Yeah, I know.  Who’d want a pet that wants to bite your fingers off?  Apparently a lot of Japanese pet owners felt the same way, as the turtles were abandoned in rivers and ponds.

But the Snapping Turtle is a prolific breeder, with mother turtles laying as many as 20 to 30 eggs at a time.  Once hatched, the turtles settle into a life of preying on frogs, fish, amphibians, birds, and native plants.  The Environment Ministry designated Snapping Turtles an alien species in 2005, banning their import and breeding.

The problem is especially vexing in Chiba Prefecture, east of Tokyo, where the claustrophobia of the megalopolis gives way to open spaces and natural areas. Parents are reporting the turtles nipping at kids and fishing nets being bitten through.  Fishermen in one pond caught 44 snapping turtles just in June. 

“By the time an increase in the population of snapping turtles is noticed, there is likely to have been considerable damage to the ecosystem already,” said Shizuoka University Conservation Biologist Hideaki Kato.  “Governments should understand that this is a pressing issue and should quickly move to grasp the situation.”

Chiba has been hunting the turtles since 2004, but it’s difficult to get volunteers to take part – they are Snapping Turtles, after all.  And they can grow as big as a meter long, weighing up to 35 kilograms.

Prefectural governments are at a loss about what to do.  Snapping Turtle eggs were found in a pond in Tokyo’s Ueno Park, a popular green space and cherry blossom-viewing park in the heart in the biggest of big, big cities.  And in Shizuoka, west of the capital, authorities who already have their hands full battling non-native raccoons now have to deal with evidence of Snapping Turtles running in the Kano River.