"Japan's Secret Garden"

PBS Airdate: December 19, 2000
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NARRATOR: In central Japan, a spider weaves her web in a field of growing rice. Rice has been a part of Japan for so long that it has shaped the land. Indeed, it has become so much a part of the Japanese landscape that it has created a unique environment essential to both the people who created it and the wild animals that now share it.

Japan is a country of steep mountains surrounding wide flat plains where people have lived for thousands of years. The country's largest freshwater lake, Lake Biwa, lies not far from the ancient city of Kyoto.

The slopes that stretch down toward the lake have been terraced. Rice seedlings need shallow water in which to grow and the neat meticulously constructed paddy fields provide just this. Some of them have been cultivated continuously for thousands of years.

Alongside them stand patches of woodland where, for centuries, the people have found their fuel and their food.

This is a land that has been ruled for centuries by the demands of the rice, yet it is still dominated by the rhythmic cycle of the seasons as they change throughout the year.

This is a landscape that the Japanese people hold so close to their hearts that they have a special word for it. They call these places where the forested mountains meet the terraces of rice, "Satoyama."

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Narrator: It's April now. The days are lengthening and it is getting warmer. Spring is on its way.

As the progressing year brings changes to the country, there is also another rhythm, which transforms the land as it has done for centuries. Early in the spring, the dry fields are turned into wetlands. The cold mountain water spreads over the dry fields. As they slowly fill, the water once again links them both to the mountains above and to Lake Biwa below. Gradually, it seeps into the earth, reawakening the soil after the frozen months of winter, and rousing the small creatures that have lain dormant there since the autumn. Mountain water is rich in nutrients so each year its return enhances the fertility of the rice fields.

Early spring is a time of intense work for the farmers, as they prepare their fields for the rice.

Satoyama is an environment created by human beings, certainly; but it is also one that is in harmony with the natural world that surrounds it. Animals on all sides are awaiting the return of the water.

Woken from her hibernation and attracted by the fresh scent of water, a pond turtle moves down into this new wetland. Here she will mate, and in a few days time she will lay her eggs on the terrace banks.

Tree frogs return to the flooded paddies to feed and to spawn.

Insects of many kinds gradually appear. Over a thousand different species of them will eventually find what they need in the rice fields.

A fire-bellied newt starts its search for food.

Some creatures have come to the flooded fields from a considerable distance away. Others have been here all through the year. This water scorpion spent the winter months buried in the dry earth. It, too, has been aroused by the cold mountain water.

Many of these small creatures become prey for water birds, which time their arrival to coincide with the flooding of the terraces.

The rhythm of change—from wet to dry and back again—was imposed on this landscape by farmers so long ago that it has now become an integral part of the workings of the natural world.

The people themselves are also governed by the rhythms of the season. At crucial times they hold festivals to ask the gods for a healthy crop and a bountiful harvest. They regularly pay their respects to the forces of nature that still control their fields.

Irrigation canals lined with cement link these terraced fields to Lake Biwa. And on a spring night in May, catfish from the lake fight their way up them, struggling against the flow of the water. The flooding of the terraced fields, combined with seasonal rain, has created many waterways that lead down to the lake. For the catfish, the timing is crucial. One after another, they laboriously make their way up the channels into the newly planted rice paddies.

They have spent the winter in the deep waters of the lake, but now they need shallow water and mud in which to lay their eggs. Satoyama provides them with exactly what they want.

Just before dawn, adult fish congregate in one of the rice paddies and begin to court amongst the newly-planted rice seedlings. The female is large and heavy with eggs. A male, who is smaller, follows her, trying to attract her attention. Entwining his body around hers, he rubs her abdomen, stimulating her to lay her eggs, which he will then fertilize.

Their coupling is sometimes so vigorous that they often damage the newly planted rice seedlings, but the farmers, nonetheless, gladly share their fields with such wild creatures as these.

The spawning is all over within a single day. The adult fish then return down the waterways to the lake, leaving behind them countless tiny eggs in the flooded fields.

Two days after spawning, the embryonic fish are moving inside the security of their tiny egg capsules. And then they hatch—in millions—and tiny fish swim out to disperse through the waters of the rice paddies.

Day by day, as the earth tilts fractionally more toward the sun, daylight lasts longer and the shallow water becomes warmer. The emergence of the catfish has coincided miraculously with a sudden abundance of food.

The earth of the paddy fields, when they were dry, contained millions of microscopic eggs, laid the previous year by water fleas. Now that the paddies are flooded once again, these eggs also hatch. So the waters have become rich with food.

A dragonfly larva is hunting. The water fleas are an easy prey. The young catfish are also feeding on them and growing quickly.

As the seedlings sprout, the land is transformed yet again and turns green. Beneath the surface of the water the duels between the hunters and the hunted continue: a water stick-insect sits, poised, waiting for its prey to come within range; and a dragonfly larva, once a hunter, now itself becomes a victim. A water scorpion conceals itself in the mud. The young catfish seem totally unaware of the danger that threatens them. A blood-worm, the larva of a midge, is food for a fire-bellied newt.

The giant water-bug is a giant indeed. It's the largest insect in Japan and a formidable hunter. With grim persistence, the giant water bug sucks out the nutritious fluids from the frog's body. The empty husk will then be cast aside and be absorbed into the mud.

A black kite hunts above one of the small patches of woodland that grow alongside the terraced fields.

These woods are a vital element in the complex world of Satoyama. They act as water reservoirs, absorbing the falling rain and then gradually releasing it so that it can seep down through the soil to the plains, there to evaporate and so to return to the atmosphere.

The woods have been used for centuries by the local people who come here to forage for food, to gather firewood and to make charcoal. Many of the oaks have strange multiple trunks. This is because they have been used by the people to grow a delicacy that is much relished by Japanese gourmets.

The slender trunks and branches of oaks are regularly cut and then stacked in piles called hodagi. They are then left for about a month to dry out. When the sap has all gone, holes are bored into them. Plugs, made of a mixture of sawdust and mushroom spawn are then hammered into each hole and sealed with a plug of wood. Shiitake mushrooms eventually sprout from the plugs of wood, and Japanese cooks will pay high prices for them.

The oak tree, in spite of its harsh treatment, does not die. Its stump sprouts once more. It will not be cropped again for eighteen years or so. As the young branches grow, they attract new visitors. Longicorn beetles come to drink their sap.

The larvae of the silkworm moth prefer more aged branches. Having fed on the leaves, they spin their cocoons. Silk from these provides another crop for the people and has done so for centuries. They use its thin delicate filaments, spun together into a thread to weave the most sumptuous of fabrics. For the caterpillar, the silk will serve as a shroud beneath which it will transform itself into a winged adult.

So the long rhythms of the forest repeat themselves.

After five years the hodagi logs are exhausted and of no further use for growing mushrooms, so they are dumped and left to rot. The humus produced by their decay seeps back into the ground where it is reclaimed by the roots of living trees and provides food for other creatures.

The larva of the scarab beetle is one of them. Having spent half a year as a grub, feeding voraciously, it has now turned into a pupa. Its newly formed shell is still soft. In Japanese, this insect is called "kabutomushi," as the shape of its head reminds people of the war helmet worn by the Samurai and the plates of its body of the armor of those ancient warriors of medieval Japan.

As spring changes to summer, so the flooded fields become grasslands.

This is the time when the giant water bug lays its eggs. The female produces as many as eighty in one patch. Having done so, she abandons them. But the male remains on guard and stays with them for over a week. Every now and then, he leaves them briefly to collect the water necessary to keep them moist. One week later, in the middle of the night, the giant water bugs begin to hatch.

It's summer and water from the forest continues to flow down into the rice fields. It travels along their network of channels and then goes on down to Lake Biwa.

The young catfish are now at about two months old. It's time for them to prepare to leave these warm shallows and to make their way down to the deeper colder waters of the lake where they will spend most of their adult lives.

Their parents came up through the farmers' waterways to reach these rice fields. Now their offspring use the same channels to take them down to the lake. Without the work of the farmers and the methods they have developed to grow their rice, the catfish of Lake Biwa would not have these extensive nurseries. Once they reach the safety of the lake, they will stay for two to three years, feeding and growing, until the time comes for them, too, to swim back up the very same channels to spawn.

Now another small creature is preparing to leave the rice fields. It uses a different exit. The larva of the red dragonfly, after two months of feeding, crawls up the rice stems from which it will launch itself into the air. To do that it must first change its shape and acquire wings.

The dragonfly will leave these terraced fields and fly away to the nearby mountains for the summer months. So it forms a link between the world of Satoyama, the cultivated land, and the wilderness that surrounds it.

The end of June. It is midsummer. The days are long and warm. The people living in the small villages alongside the rice fields make their own special contributions to the living landscape of Satoyama. The flowers in the gardens are an important source of nectar for many species, including swallowtail butterflies.

In the corner of a village garden, a large spider waits on its web. As in many parts of Japan, spiders are welcomed and encouraged to stay as a sign of good fortune. They do, after all, feed on insects which may be harmful to both people and crops.

In a hackberry tree, another small life is about to take its place in the Satoyama community. This is Japan's national butterfly, called oo-murasaki. The purple of its wings is the color that once could be used only by the Emperors and the high priests of ancient Japan. In its caterpillar stage, it lives only on these hackberry trees. As an adult, it will fly away to feed on the sap of trees in the woodlands.

During the warm summer nights, the rice paddies become alive with another insect much loved by the Japanese: fireflies. Using the language of light, they signal courtship messages to one another. Their adult lives are brief, a mere seven days or so. Japanese families, by tradition, come to watch the fireflies every year at this season—to marvel at the tiny lights winking over the rice fields and to ponder on the fragility of the lives of those that produce them.

Fireworks are a special treat on these summer evenings. In a corner of the garden, behind the children and their fireworks, another life is undergoing dramatic change. For seven years, this cicada has remained underground. Now it is emerging to spend the last few days of its life as a winged creature in urgent search of a mate. There are many species of cicada in Japan. Each has its own characteristic song and each is a reminder to the people of another stage in the passing seasons.

It is high summer. The rice has been growing steadily, but there is still a great deal of work to be done. The terraces must be kept free of weeds to allow the rice to grow freely. It's hot, hard labor.

The farmers wade out into the shallow ponds that adjoin their rice fields. These man-made reservoirs hold water throughout the year and the people stock them with carp. Now, that harvest can also be gathered. They have their own special devices with which to collect it. Each family takes home its own catch. It's an annual seasonal feast that everyone enjoys.

Summer is a holiday time for the children, and while their parents work in the fields they make the most of the long evenings. The pleasure and fascination that so many Japanese find in insects shows itself early in life. Stag beetles are particular favorites. The larger the better. The male beetles, when confronted with one another, will do what comes naturally—they will fight for control of a territory.

A scarab beetle has emerged from under its pile of hodagi logs. As night begins to fall, it climbs out to look for the sap it feeds on. Through the night, battles will be fought and lost as each beetle strives for the control of the best places. And it's not just that they themselves want the sap. Good feeding spots also attract females. So, like the samurai they so resemble, they do battle.

It is September. Summer is vanishing with the shortening days and the rice fields are about to change yet again. Soon it will be time for the harvest.

One hundred and fifty days ago, these terraced fields became wetlands as water from the mountains flowed into them. Since then they have been slowly changing in time with the seasons. As each field was transformed, different species arrived to take advantage of the changing scene. For the farmers, and for the rice, this year has been a good one.

The red dragonfly returns from the mountains to the land where it hatched. It is time for the people to collect the rewards of so many months of labor.As the rice dries in the autumn sun, the air is full of the scent of hay.

There is now no place here for the giant water-bug. Other insects are also abandoning the drying fields. They take to the wing and fly away in search of the water that they still need. The reservoirs provide a new home for those water creatures that once hunted through the rice paddies. Here they will be able to spend the winter in safety.

As the land changes color and the autumn leaves fall to the ground, the pace of life slows. Tree frogs that hatched out in the rice paddies have now returned to the nearby woodlands and prepare to hibernate under a blanket of fallen leaves.

Before the very last puddles disappear from the harvested fields, there is one final act of creation. In a ritual courtship flight, the red dragonflies mate. The male clasps the female and she repeatedly dips the tip of her abdomen into the puddles, depositing her eggs. The eggs will remain dormant through the bitter cold of winter. When spring returns and the mountain water flows once again into these fields, they will hatch out and a new generation of savage larvae will prowl through the waters of the paddies.

For centuries, persimmon trees have been planted along the rice terraces. They are an autumn fruit much loved by the Japanese. They are gathered singly and with great care.

The persimmon trees are essential for the many damselflies that now gather around their branches overhanging the rice paddies. Like the dragonfly, the damsel too has changed its behavior to take advantage of the landscape created by humanity. The damselflies lay on these branches, twisting their ovipositors so that their eggs will be placed in safety beneath the bark. And then they die. When spring comes and the rice paddies fill once again, the damselfly larvae will drop directly into the waters.

In the harvested fields, the dragonflies indulge in a final bout of egg-laying.

The skinned persimmon fruits are neatly hung by the farmers' houses. These, carefully dried, used to be a valuable winter food for the people of Satoyama, and also a source of much-needed cash. Today, when food of one kind or another is easily available all the year round, fewer farmers bother with the persimmon crop. Even so, the appearance of the drying fruit so carefully placed on their racks is recognized by all Japanese as a sign that winter is fast approaching.

As the land freezes, little life is visible in and around the rice fields which are now covered by a blanket of snow. Yet there is life there, hidden, and quietly waiting for the renewal that will come when the waters return once again with the sun. Winter is also a time of rest for the farmers. For their lives, too, are, perforce, attuned to the natural rhythms around them.

At the edge of this rice field a small natural spring bubbles out from the ground. It will remain unfrozen throughout the winter, and at its edge the local people place floral offerings to the gods for this gift.

In a muddy bottom, a water scorpion waits asleep, neither moving nor breathing.

Winter settles in. On the edge of a frozen rice paddy, a farmer's hut stands deserted. But in a corner, there is a reminder of the spring that will come—the chrysalis of a cabbage butterfly.

February. The year has turned. The faint heat of the distant sun warms the land long enough for a cold mist to rise from the thawing fields. Winter is loosening its grip. Soon work in these fields will resume. Once again, the mountain water will flow, the rice will be planted, and visitors from the woods above and the lake below will come back. Once again, Satoyama will be filled with life.

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Japan's Secret Garden

Narrated by David Attenborough

Written by
David Attenborough
Jeremy Hogarth
Satoko Saito

Produced and Directed by
Shinichi Murata
Tetsunori Kikuchi

Produced for NOVA by
Marti Louw

Program idea conceived by
Mitsuhiko Imamori

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Tetsuo Matsumoto

Sound Editor
Rob Todd

Assistant Sound Editors
Christina Hunt
Dan Vanrokel

Mitshuiko Imamori
Hiroyuki Kozako

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Chisato Ushiyama

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Ray Loring

Mary Ellen Miller - Shakuhachi
Cathleen Ayakano - Koto

Video Post Production
Shigeki Nobayashi
Seiji Tsutsumi

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Alan Gerrie
Saori Ono
Akira Fukada

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Mike Baskerville

Online Editor
Will Hearn

Elaine Ford

Special Thanks
Lake Biwa Museum
Shiga Prefectural Agricultural Experiment Station (Kohoku Branch)
Kashihara City Museum of Insects
Michael Stedman
Natural History New Zealand Limited

Executive Producers for NHK
Yoshimizu Kawano
Hiroyuki Wakamatsu
Shinichi Murata

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Martin Brody
Michael Whalen

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Lisa D'Angelo

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Evan Hadingham

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Melanie Wallace

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Alan Ritsko

Executive Producer
Paula S. Apsell

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