The island looking to China for brides
Japan's population has been gradually ageing and shrinking for several years. Remote communities far from the big cities are feeling the changes most - places such as Shiraishi-jima, one of hundreds of small islands which dot the Seto Inland Sea.
In the classroom of a secondary school on a hill overlooking the Inland Sea, Sunao Amano is giving a talk with slides.
Outside it's a sultry summer's day. Swallows skim to and fro above the little fields of mulberry bushes.
The classroom windows are open and Amano's words of wisdom drift lazily out on the afternoon breeze, mingling with the plaintive calls of distant buzzards cruising on the thermals.
Amano is not a regular teacher. He's a local farmer who grows snow peas and squashes for a living. He's been invited to the school to describe the work he does, and maybe try to convince his audience that they too might one day make a living out of growing vegetables.
Amano's talk is a red-letter day for the school, an imposing two-storey building, complete with sports ground, gym and running track. All the pupils are there to listen. All eight of them. The entire seven-strong teaching staff has turned out too.
The little island of Shiraishi-jima is just a 20-minute ferry ride from the mainland port of Kasaoka. But the short hop from the hubbub and the hurly burly of Honshu's jam-packed south-eastern seaboard to the island's soft and languid silences is like a trip to a different world.
The island is roughly three miles long, and mile or so across. Its granite spine is a switchback range of steep forested hills crowned with rock formations sculpted by wind and rain. From the top there are spectacular views over the island spangled Inland Sea.
Amy Chavez was born and raised in the American state of Ohio. She came to Shiraishi 17 years ago, fell in love with the place, and has lived here ever since. She earns a living as a freelance writer and running a summer beach bar on the island's main strand. When Chavez first arrived on the island there were nearly 1,000 people living there. Today there are just 570. Many of them are elderly.
In fact there are some people on the island who seem incredibly old. Gnarled and wizened with weather-beaten faces, the colour of teak, they look like ancient trees from a Japanese garden. But they're incredibly sprightly too. Out - at daybreak - hoeing their vegetable plots, or trundling their shopping trolleys at a rate of knots up the steep little lanes out of the village.
A comparative youngster is 68-year-old Taiko Amano. All of her 11 children have upped sticks and left the island, and Taiko is a widow. But she says she will never leave the island. Her house is the home of her dead husband's ancestors, and she must care for them. Besides she loves her island.
But people are leaving. In the village there are scores of houses where now only the ghosts of dead ancestors reside. Shuttered, they stand silent and empty.
Things might be different if there were job opportunities. There was once a stone quarry on the island. But that closed.
Fishing is the main occupation. A handful of fishing smacks sail out from the harbour - sea bream and Japanese Spanish mackerel are regular catches. But some of the island's fishermen have also been trawling for wives. Shiraishi-jima now has five Chinese brides, and they've had 11 children.
With more children running around, there's hope the threat to close the island's school may yet be fought off. Amy Chavez thinks closing the school would be a tipping point for the island, it would stop being a real community then. Should that matter? One more Japanese village which puts the shutters up?
The answer - as far as Chavez is concerned - is to be found as night falls on a patch of dusty gravel behind the village hall. To a drumbeat which has echoed here down the centuries, the villagers are practising a dance called the Shiraishi Odori. It commemorates a sea battle fought 800 years ago between rival clans in which it's said the Inland Sea turned crimson with the blood of the dead.
No other island in the Seto Sea has the dance for each island is unique. If Shiraishi-jima dies - its traditions and folk memories will die with it, and a tiny part of the planet's cultural DNA will have been lost forever.
Up at the school on the hill Amano gave his talk on the cultivation of snow peas, the walls are hung with photographs of happy looking students on school trips to Tokyo. The lure of the bright lights burns strongly for most young people, but hopefully Amano can persuade some of them there's a happy future to be had here on Shiraishi-jima.
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