we finally ventured to the moon.

人類が月に到達したのは

For the very first time, we looked back at our own planet.

わずか50年前のことだ

Since then, the human population has more than doubled.

その時に我々の住む惑星を 初めて一望できた

This series will celebrate the natural wonders that remain

初の月面着陸以来 人口が二倍以上になった

and reveal what we must preserve

このシリーズでは 残存する美しい自然を尊び

to ensure people and nature thrive.

人類と自然が 両方 繁栄できるために

Forests.

守らなければならないものを 明かしていく

Over half of all the world's trees, evergreen and deciduous,

森林

stand in these great assemblies.

地球の全樹木　落葉樹 常緑樹の半分以上が

[birds chirping]

森林の中にある

[narrator] For many of us, they are places of mystery and darkness.

私達の多くにとって 神秘と闇に包まれた場所

They are key to our climate, and home to countless unique species.

森林こそ 気候 そして 無数の生物の運命を握る

In the past, we have destroyed them without hesitation.

かつて人類は躊躇せず 森林を破壊してきた

Yet, forests do have an astonishing ability to recover.

森林は驚異的な回復力を持つ

This is the southern edge of the boreal forest,

森林

the forest that dominates the far north.

ここは 亜寒帯林タイガの最南端

It stretches eastwards across Russia for thousands of kilometers,

極北の大部分を 森林が覆っている

and now, in the middle of winter, it's largely silent,

ロシア全土を覆うように 何千ｋｍも東へと続く

seemingly empty of animals of any kind.

真冬の今は 静寂に包まれている

But this is the home of an animal so rare it's almost mythical.

生命の片鱗も感じられない

A Siberian tiger.

しかし ここには 伝説のように

There are less than 600 of them.

極めて稀な動物が 生息している

[caws]

アムールトラだ

[tiger growls]

600頭未満しか 生存していない

[narrator] These are the most intimate  pictures of them in the wild yet taken.

これはカメラが捉えた最も 至近距離のアムールトラ

A male Siberian tiger patrols a territory of almost 2,000 square kilometers,

オスが約2000平方kmの テリトリーをパトロールする

and it has to do so if it is to find enough prey

長い冬を超すのに必要な

to keep itself alive during the long winter.

獲物を探すためだ

This is an impoverished land where food of any kind is scarce.

ここは食料が育たない 痩せた土地だ

A pine cone.

松ぼっくり

Pine nuts provide vital energy during the winter months.

松の実は冬季の重要な 栄養源だ

Wild boar depend on these nuts.

イノシシはこれで命をつなぐ

For them, it has to be grab and go,

食べたらさっさと 移動しなければ

for they themselves are food for a tiger.

彼らがトラの 食料となりえる

[squeals]

動物達は松の実を探すのか それを探す動物を探すかで

[narrator] This game of hide-and-seek is played out over vast areas of forest,

この隠れんぼは 森全体で行われている

as all the animals search for the life-giving stands of pine.

密猟によりアムールトラは 絶滅寸前となった

Poaching has taken the Siberian tiger to the brink of extinction,

しかし 80年代から徐々に 生息数を回復し始めている

but, since the 1980s, their numbers have slowly increased.

この稀な映像から分かる事は

These rare glimpses reveal

彼らの運命は狩りができる程

that their future still depends on having vast areas of forest in which to hunt.

広大な森の存在に かかっているという事だ

The boreal forest extends from Russia in the east,

亜 寒帯林タイガの東側は ロシアから始まり

across Europe, to North America.

ヨーロッパをわたり 北米にも広がっている

It contains 750 billion trees,

7500億本の木々が植生し

and it stores over 40 percent of the world's carbon,

地球の炭素の４割以上を 貯留している

making it a vital element in the fight against climate change.

気候変動との戦いの 欠かせない要素である

During the winter, the days are so short and the temperature so low,

冬の間 日照時間は短く 極寒となり

that growth is at a standstill.

成長する動植物はない

This far north, the forest can support very few animals

熱帯雨林地域の 森林と比べ ―

compared to the rain forests  of the tropics.

これ程北にある森林は 養える動物は数少ない

Many are dependent on the supplement to be found in its rivers.

多くの動物が川魚から 栄養を採っている

[birds caw]

アラスカ西部では 春と 現在のような秋に ―

[narrator] In western Alaska, both in spring and, as now, in autumn,

海から鮭が

salmon, having left the ocean,

産卵のために帰ってくる

swim up rivers to reach their ancestral spawning grounds.

鮭が森に帰ってくると

Their journey from the sea into the forest represents

一気に栄養が行き渡り始め

the greatest transfer of nutrients from one habitat to another

世界中の食物連鎖に波及する

anywhere on Earth.

鮭は森に生息する捕食者に 欠かせない冬の食料だ

The fish are crucial seasonal food

白頭鷲ハクトウワシは年中ここに住み 川近くに巣を作る

for all the predators that live in this forest.

まだ頭部が黒い若鳥は ―

Bald eagles live here the year round and nest close to the river.

最初の数年は 食料を求めて森を飛び回る

[piercing chirp]

その後 この４歳のメスのように

[narrator] Young eagles,  still without white heads,

川に食料を探せる程 大きくなる

spend their first years searching for food in the forest.

最初のうちは残飯にしか ありつけない

But, like this four-year-old female,

それすらも弱肉強食の 奪い合いだ

they're now big enough to try and claim a place on the river.

若鳥は場所を 移るしかない

At first, all she can get are the scraps left by others.

この 亜寒帯林タイガは広大だが ―

And she can't get even these without a fight.

鮭の産卵場所は 捕食者すべてが知っている

[eagles chittering]

川が凍り始めると 争奪戦が激化する

[narrator] She will have to  look elsewhere.

首尾よく捉えた獲物は すぐにライバルの標的だ

The boreal forest may be vast,

メスドリの強みは

but the places where the salmon spawn are known to all the predators.

若くてもオスより 体が大きいことだ

As the rivers begin to freeze over, competition becomes even more intense.

それが勝負を決めた

This youngster is lucky, but her success is noticed immediately.

冬の最中

[chittering]

若者もお年寄りもこの過酷な 寒さに耐えなければならない

[narrator] She does have one advantage.

生き残ったものだけが

Females, even when young, are larger than the males.

地上で最も広大で 過酷なこの森で

And here, size matters.

居場所を得る

[cawing]

少し南下すると

[narrator] As winter advances,

かつて広大だった セコイアの森の残存がある

young and old have to meet the challenge of the intense cold.

そう遠くない昔

If she can survive, she will have gained a place

この森は太平洋岸北西部 一帯に広がっていた

in one of the greatest and harshest forests on Earth.

現存するのは そのわずか５%だ

A little further south

ここは北部ほど 過酷ではない

stand the last  of the great redwood forests.

太平洋から暖かく湿った 風が吹き

Not so long ago, these great trees grew throughout the Pacific Northwest.

一年を通して木が育つ

Now, only five percent of them remain.

霧深い森の足元では

Here, conditions are less harsh.

多様な生物が生息する

Winds bring in warm, humid air from the Pacific Ocean,

オスのサメハダイモリだ

so the trees are able to grow the year round.

毎年春になると 生まれた池へ戻ろうという ―

Hidden in the vegetation of the moist forest floor

不思議な本能に 突き動かされる

is a richly populated underworld.

遅れをとってはならない

A male rough-skinned newt.

他のオス達も

Every spring, he is driven by a mysterious urge

池に急ぐ

to return to the pool where he hatched as a tadpole.

メスを探しに行くためだ

And he needs to get there quickly.

しかし成熟した森を 数百ｍ進むのは簡単ではない

Because there are lots of others like him...

ライバルが次々に到着する

with exactly the same idea.

メスもオスを待っている

They're all searching for a female,

交尾の後も

but trekking across hundreds of meters of old-growth forest is not easy.

メスの産卵が終わるまで オスはメスの 側そばを離れない

There is strong competition.

隙を狙うオスで 辺りは一杯だ

And the female is anxious to get going.

熾烈な争奪戦

Once paired, he hangs on,

その中心にいるメスが 溺れ死ぬ場合も出るほどだ

for she may take several hours to discharge all her eggs.

最初の相手であるこのオスは メスを離さない

Other males are only too eager to displace him if they can.

数週後にはおたまじゃくしが 孵かえるだろう

Competition is so vigorous

完璧なタイミングで 森は大変身を遂げていく

that the females in the center of these writhing balls

夏の終わりまでには

have been known to drown for lack of air.

照りつける太陽で

But her first partner maintains his grip.

木がカラカラに乾燥する

Within weeks, their tadpoles will hatch.

強風が火に勢いを加え ―

And none too soon, for the forest is about to change dramatically.

気温は700℃にもなる

By the end of the summer, the sun has baked the forest so intensely

鎮火した後の森は ひどい状態だ

that they are as dry as tinder.

むき出しの地面を 吹き抜ける風が

Strong winds drive the flames,

じん 旋風せんぷうを巻き上げる

and temperatures rise to 700 degrees Celsius.

死の森と化してしまった かのようだ

Its aftermath is seemingly total destruction.

しかし　森は生きている

The wind, scouring the newly exposed forest floor,

わずか数ヶ月で

kicks up dust devils of ash.

草花が地面に溢れる

The ground appears to be devoid of life.

実際 多くは火の洗礼を 受けて初めて発芽する

But the forest is far from dead.

地面まで陽の光が 届く様になり ―

Within only a few months,

新しい生命が息吹く エネルギーを与える

flowers and tree seedlings will rise from the soil.

成熟したセコイアは

Many, in fact, would not have germinated had they not received a baptism of fire.

ぶ厚く 火を通さない 樹皮に守られ無事だ

[birds chirping]

この森の生存には この 自律的な回復力が欠かせない

[narrator] Light streaming down through the newly opened canopy

自力では回復できない 森がほとんどだ

provides the energy for a surge of new growth.

回復を助けるのは動物達だ

The older, well-established redwoods have survived,

森とそこに暮らす生き物は 共存している

protected by their thick, fire-resistant bark.

その関係が特に顕著なのは

This natural resilience is essential to the continued health of these forests.

インドの西ガーツ山脈だ

Most forests, however, cannot recover on their own.

世界有数の生息地である この森には ―

Many are helped to recover by animals.

インドの動物種の １/３が生息する

The trees and their inhabitants are interdependent.

たとえば　シシオザル

And nowhere is this dependence more apparent

彼らは多くの種類の 木の実を食べ

than in India's Western Ghats.

ふんと共に無傷で出る種を 撒き散らす

This globally important habitat

しかしサルは基本的に 遠くまで移動しない

contains a third of all animal species found in India.

植物が遠くにも 種を撒くとするなら ―

[animals whoop and chirp]

別の手段が必要だ

[narrator] Lion-tailed macaques.

翼

They feed on the fruits of many kinds of tree,

羽を伸ばすと約２ｍある オオサイチョウは

and, in doing so, they distribute the seeds,

食料探しに遠くまで飛べる

which will emerge unscathed with their droppings.

約40種の果物を食べる 彼らは

But few monkeys travel very far.

種を遠く

If plants are to distribute their seeds across great distances,

西ガーツ山脈全域に運ぶ

they need another kind of transport.

そのため 木にとって オオサイチョウは上客だ

Wings.

イチジクは美味しいが

Great hornbills have wings that are almost two meters across,

栄養価は高くないため

and they enable the birds to travel long distances in search of food.

たくさんの量を 食べる必要がある

Hornbills feed on the fruit of 40 or so different kinds of trees,

疲れてしまう

and transport the indigestible seeds they contain

しかも　競争もある

all over the Western Ghats.

実をつけたイチジクの木には 多くの鳥が集まる

So, it's to the trees' advantage to attract the hornbill's attention.

熾烈な戦いの始まり

The figs themselves, although they taste nice,

オス同士の空中戦を カメラが初めて捉えた

are not, in fact, very nutritious,

戦いの理由は 明らかにされていない

so the hornbills have to eat great quantities of them.

食べ物の奪い合い かもしれないが

It can be tiring work.

それ以上の理由がありそうだ

But it's not a free-for-all.

勝者はここに来るメスに

A single fig tree in fruit attracts great numbers of hornbills.

強さとスキルを 見せつけることができる

Competition between them is intense.

オスは明らかにメスに 取り入ろうとしている

This aerial jousting between males has never been filmed before

オオサイチョウは 相手選びが時に重要だ

and its purpose is not really understood.

なぜなら 一度結ばれた夫婦は

It may be that the birds are simply squabbling over food,

一生離れないからだ

but it seems rather more than that.

鳥同士の戦いに 森も恩恵を受ける

[squawking]

敗れた鳥は遠くまで 食料を探しに行き ―

[narrator] The winner  is able to  demonstrate his strength and skill

種を広く撒き散らすからだ

to visiting females.

森林での植物と動物の関係は

The males certainly seem keen to ingratiate themselves.

いつも穏やかとは限らない

It's particularly important for hornbills to get the best pairing

アフリカ大陸最大の森 ミオンボ森林

because, once established, the bond between male and female

ここで広く植生する 木が名前の由来だ

will last a lifetime.

西はアンゴラから 東はモザンピークまで

The forest also benefits from these squabbles,

1600kmを超え 広く分布する

because even a defeated hornbill

乾季には

will spread seeds over wide areas as he searches for his next meal.

アフリカ中の動物が ミオンボを求めて集まる

The relationship between trees and animals in a forest

象は栄養価の高い草を好むが

is not always so harmonious.

それがなければ

This is Africa's largest forest, the Miombo,

生い茂るミオンボの葉や 枝を食べる

named after one of its common trees.

象だけではない

It stretches for over a thousand miles,

モパネワームは

from Angola in the west to Mozambique in the east.

見ての通り みみずワームではなく 毛虫だ

At the height of the dry season,

同時に大量に卵から孵化する

the Miombo attracts animals from all across southern Africa.

新芽が顔を出し始めると

[trumpeting]

大食い競争開始だ

[narrator] Elephants prefer grass  if they can get it. It's very nutritious.

大食漢の彼らは

In its absence,

わずか６週間で 40倍の大きさに成長する

they browse on the abundant leaves and branches of the Miombo.

総勢100万の大軍が 成長した頃には

[elephants huffing]

森の葉は 食べ尽くされてしまう

[narrator] But they're not the only  hungry ones here.

それでもミオンボは 回復する

These mopane worms

毛虫がいなくなると

are not worms, of course, but caterpillars.

木は再び新芽を吹き出す

They hatch simultaneously in huge numbers.

この新芽を狙うのが象

And just as the forest is putting out new leaves,

毛虫ほど より好みをしない

they begin their attack.

木のすべてを食べる

They feed so voraciously

空腹の象は１日に200kgの 植物を食べられる

that in just six weeks they increase their size 40 times.

このような 一見すると破壊行為でさえ

By the time they're fully developed, this million-strong army

アフリカきっての 絶滅危惧種の存続に

will have stripped the entire forest of its foliage.

貢献している

But the Miombo bounces back.

ハンティングドッグだ

With the caterpillars gone,

彼らは草原でよく見られるが

the trees produce a second growth of leaves.

この様な開けた森こそ 彼らが好む生息地だ

This fresh feast then attracts elephants.

大量に食べ歩く象が森を開き

They are less fussy than the caterpillars.

それが犬の狙う 動物を引き寄せる

They will eat every part of the tree.

ミオンボの森ほど狩りに 適した場所はない

And a hungry elephant can munch through 200 kilos of vegetation in a day.

子育てにも最適だ

Yet, even this destruction has its benefits.

狩りから帰った親犬を

It shapes the forest in a way that helps one of Africa's most endangered animals.

子犬が大興奮で迎える

Hunting dogs.

皆腹ペコだ

They're seen most frequently, and most easily, on grasslands.

生後３ヶ月の子犬は地下に 隠れて暮らす

But, in fact, these open forests are their preferred habitat.

殆どの時間を外で 過ごせる程 自信が付いた

[grunts]

わんぱくなのは どの子犬も同じ

[narrator] Browsing elephants  open up a forest,

遊びを通して ―

and that attracts the animals on which the dogs prey.

社交的な絆を 築いていく

[barks]

成犬になり狩りをする時 仲間の絆が必要になる

[dogs yipping]

狩り そして 避難所として ―

[narrator] For the dogs, the Miombo forest is perfect hunting country.

彼らにとって ミオンボは 昔から常に重要であった

And it's also an excellent place in which to bring up pups.

しかし絶滅の危機に瀕した 今ほど

The pups greet the adults returning from a hunt

重要であったことは かつてない

with great excitement.

彼らが生き残るためには―

[squealing]

他の生物の生存が欠かせない

[narrator] Food.

マダガスカルの森では ―

The first three months of the pups' lives are spent sheltering underground.

不思議な形をした木が目立つ

[soft growling]

バオバブの木だ

[narrator] Now, they are confident enough

この島は８千万年以上 孤島だった

to stay out in the open for much of the time.

この膨大な月日をかけて

And then, like all puppies, they have fun.

動植物は独自の進化を 遂げてきた

Playing is important for the youngsters,

世界でも特に貴重な 森であるのはその為だ

for as they do so, they establish the social bonds

これはサルではなく 遠縁のキツネザル

that they will need when they start to hunt together as a team.

40種類以上の キツネザルがいる

-[bird squawks] -[squealing]

どれもマダガスカルのみに 生息する絶滅危惧種

[narrator] The Miombo has always been  important for hunting dogs,

キツネザルは この森に欠かせない

both as a place to find prey and as a refuge.

彼らがいなくなれば 絶滅する植物ある

Never has it been more crucial

キツネザルを主食とする 動物もいる

for the survival of this endangered species than now.

マダガスカル最大の捕食者

But they will only survive if other creatures are here

現れると緊張が走る