欢迎收看美洲大地 This is The Americas.
这段非凡的旅程 横跨地球上这片超级大陆 An extraordinary journey across Earth's great supercontinent.
地球上物种最丰富的地区 The widest variety of life on the planet.
揭露我们家园未曾述说的故事 The untold story of our home.
今晚跟着美洲大地 Tonight on The Americas...
探索冰雪北境 The Frozen North.
跋涉穿越阿拉斯加与加拿大的荒野 An adventure through the vast wilderness of Alaska and Canada.
此地的冬季美景之下暗藏危机 Here, winter's beauty disguises her dangers.
但冰雪消融后 But when snow and ice retreat
北方大地展现出生机盎然的样貌 the North reveals landscapes teeming with life.
这里所有动物必须忍受 All animals here must endure or escape
或是逃离剧烈的季节变化 the extreme swing of the seasons
看着北境在眼前变换面貌 as the North changes before their eyes.
大陆北端是冰冻的边疆地带 At the top of the continent lies a frozen frontier
面积大于美国其他地区总和 larger than the rest of the United States.
夜晚揭露了这儿人烟多么稀少 The night reveals just how few of us live up here.
从东岸到西岸 From the East Coast to West
三百万平方哩的蛮荒大地 three million square miles of wilderness.
(哈德逊湾)
11月底 加拿大哈德逊湾清晨时分 A late November dawn in Canada's Hudson Bay.
这个时节照说应该完全结冻了 By now, this place should be frozen solid.
但今年气温还太暖和 But this year, it's still too warm.
对北极熊来说 And for a polar bear
这可是个问题 that's a problem.
牠会猎杀海豹 He's a seal hunter.
但那些海豹 But those seals
远在海冰之上 are way out on the sea ice.
目前 And right now
冰层还不够厚 不能在上面行走 the ice still isn't thick enough to walk on.
牠只得等到海面彻底结冻 He's forced to wait until it really freezes up.
几片枯叶无法填饱肚子 A few dead leaves won't fix an empty stomach.
仅仅十年 In just 10 years
北极熊数量就暴跌超过三分之一 the bear population has fallen by over a third.
等待冬天来临成了危险的赌注 Waiting for winter is becoming a dangerous game.
北极熊称霸海岸 While polar bears occupy the shore
森林则是狼的天下 the forest belongs to wolves.
冬天是狼群最佳的狩猎季 Winter is their prime hunting season.
深深的积雪拖慢猎物的脚步 When the deep snow slows down their prey.
一头驼鹿能喂饱 这个17只成员的狼群 A moose would feed this 17-strong pack.
赶出了第二头驼鹿后 狼群分头行动 As a second moose is flushed out, the pack splits.
这是个代价昂贵的大错 It's a costly mistake.
十次狩猎有九次以失败收场 Nine out of ten hunts fail.
碰上暴风雪袭来 And with this blizzard rolling in...
狼群痛失了机会 they've missed their chance.
但这不代表牠们会挨饿 But that doesn't mean they'll go hungry.
这个天候下 In this weather
毫无遮蔽的海岸地带一定会出现死伤 the exposed coastline will claim casualties.
狼群得抢先找到 The pack must find them first.
牠们很紧张 They're nervous.
毕竟这不是狼的地盘 This is not wolf territory.
一头死去的北极熊 是一顿意想不到的大餐 A dead polar bear is an unexpected feast.
牠们得赶紧用餐 They must feed quickly.
这是三不管地带 This is no man's land.
这下 加拿大两种顶尖掠食者 It's now that Canada's top predators
正面交锋 come face-to-face.
凛冬降临哈德逊湾的海岸线 As winter descends on the shoreline of Hudson Bay
森林统治者对峙冰上霸王 the rulers of the forest confront a king of the ice.
狼多势众 The wolves have strength in numbers.
但体重800磅的熊 But at 800 pounds
有量级上的优势 this bear has a massive weight advantage.
而这回 量级就是致胜关键 And this time, that's what counts.
冬季迟来渐渐成为常态 As winters arrive later
困在岸边的北极熊也愈发饥不择食 polar bears trapped on the shore are growing more desperate.
但所有栖息在此的生物 But the fortunes of all who live here
即将转运 are about to change.
为期六个月 冰雪将覆盖大片北境 For six months, winter buries much of the Far North.
这下狼群抓得到猎物了 Now the wolves will get their kill.
哈德逊湾也总算结冻 And Hudson Bay is finally frozen solid.
对北极熊来说 For polar bears
通往海豹猎场之路总算通了 the path to seal hunting grounds is clear at last.
地轴倾斜造就了北方极端的季节 The North's extreme seasons are caused by the tilt of the Earth.
极地有数个月会陷入一片黑暗 For months, the Arctic is plunged into darkness.
但太阳依旧会宣示自己的存在 But still, the sun makes its presence felt.
魔幻的景象 A magical display.
北极光 The aurora borealis.
这是太阳风暴的痕迹 These are the traces of a solar storm
因为来自太阳的辐射 as radiation from the sun reacts with gases
与地球大气层的气体起了反应 in the Earth's atmosphere.
氧气会发出绿光 氮气则是紫光 Green for oxygen, purple for nitrogen.
在加拿大的育空森林中 In Canada's Yukon Forest
二月初的气温跌至零下30度 temperatures in early February drop to minus-30.
冬季食物是如此稀少 There's so little food in winter
最好的选择是离开 you're best to either leave
或是躲着等到春天 or hide away until spring.
除非 Unless...
你是雪鞋兔 you're a snowshoe hare.
不仅完全清醒 还怡然自得 以冰封森林为家 Wide awake and perfectly at home here in the frozen forest.
雪鞋兔只靠树枝与树皮即可过冬 They survive the winter on nothing more than twigs and bark.
但牠们很聪明 But they're smart
只挑选蛋白质含量最高的植物 only picking plants that provide the most protein.
积雪都快跟牠一样高了 He's about as tall as the snow is deep.
但牠有个法宝 在这里生活起来 But he's got something
轻轻松松 that makes living here seem like a walk in the park.
带蹼的大脚 Enormous, webbed feet.
与生俱来的雪鞋 They're built-in snowshoes.
所以牠随时都能起跑冲刺 So he's always ready for a sprint start.
牠也必须如此 And he needs to be.
这片树林里可不只有牠 He's not alone in these woods.
一只加拿大猞猁 A Canada lynx.
猞猁在冬季有一种主要猎物 In winter, a lynx has one main source of prey...
就是雪鞋兔 and he's it.
牠的双耳能独立转动 His ears rotate independently.
随时注意雪中有无不祥的脚步声 Always listening out for the ominous crunch of footsteps in the snow.
被发现了 Spotted.
猞猁是矫捷的猎手 Lynx are agile hunters.
但灵巧程度略逊一筹 Though not quite as light on their feet...
雪鞋兔因而争取到宝贵的数秒 which buys the hare precious seconds.
但没有哪个藏身处安全得了一世 But no hiding place will be safe for long.
在育空地区深处 Deep in the Yukon
一只雪鞋兔动弹不得 a snowshoe hare freezes
不是冻僵 而是吓坏了 not from cold but from fear.
加拿大猞猁绝不轻易放弃晚餐 Canada lynx don't give up on dinner easily.
逃脱一定要抓准时机 So escape must be timed to perfection.
有了这些雪鞋的帮忙 With the help of those snowshoes
牠奔跑能高达时速30哩 he can hit a top speed of 30 miles per hour.
顺利脱身 A clean getaway.
真是难能可贵 And that's unusual.
加拿大猞猁很少失手 Canada lynx rarely miss.
真是只幸运的小兔子 This is one lucky bunny.
等繁殖季到来 When the breeding season arrives
就有更多野兔分散炮火 there will be more hares to take the heat.
在那之前 牠得皮绷紧一点 Until then, he'll need to stay on his toes.
艾伯塔省的冬末 一万两千呎高处 By late winter in Alberta, 12,000 feet up
落基山脉的高耸山峰 the towering mountains of the Rockies
有皑皑的白雪层层堆栈 are coated in layer upon layer of snow...
有些地方超过20呎深 in places more than 20 feet deep.
每年都有数百万旅客前来游玩 A playground for millions of visitors every year.
但小心了 But be careful.
春天的阳光松动了山上的大片积雪 The spring sunshine weakens the vast shelves of mountain snow...
引爆自然界破坏力名列前茅的事件 priming one of nature's most destructive events.
雪崩 Avalanche.
一百万吨冰雪 A million tons of snow and ice race downhill
以超过百哩的时速冲下山坡 at speeds over 100 miles an hour.
落基山脉每年都传出两千多起雪崩 More than 2,000 avalanches are reported in the Rockies every year.
还有更多次都无人见证 Many more go unwitnessed.
随着全球变暖 As the planet warms
雪崩也更加难以预测 avalanches are becoming ever more unpredictable.
在落基山脉的阴影下 In the shadow of the Rockies
就算到了四月底 even in late April
这片广大的草原依旧有降雪 snow still falls across these vast grasslands.
但无庸置疑 But make no mistake.
春天确实来了 Spring has arrived.
一群怀抱决心的舞者也抵达了 And so have a group of determined dancers.
可是这足以融化冰雪女王的心吗 But will all this be enough to melt the heart of an ice queen?
俯瞰艾伯塔省平原 Standing high over the plains of Alberta
落基山脉引导暖风顺着东面而下 the Rockies channel warm winds down their eastern flanks
这种风号称"吃雪者" winds known as snow eaters.
随着气流沉降 温度也上升 As they descend, they heat up
可让下方平原升温多达20度 raising the temperature of the plains below by as much as 20 degrees.
在草原上 Out on the prairies
大家基本上都很早起 pretty much everyone is an early riser.
最早的莫过于尖尾松鸡 None more so than sharp-tailed grouse.
牠们是来享受第一道阳光的 They're here to catch the very first rays of sunshine
但无法抗拒任何聚光灯 but they can't resist any spotlight.
雄松鸡每年四月齐聚一堂 来场求偶比舞大会 The males gather every April for a mating dance-off.
雌松鸡担任评审 奖赏就是 The females are the judges, and the prize is...
你想必猜得到 Well, bet you can guess.
破晓时分 好戏上场 As dawn breaks, it's showtime.
每秒踏脚20下 Stomping their feet 20 times per second
配上摇摆的动作 目的就是要诱惑雌性 with a shake and a shimmy, it's all about seduction.
牠们这一刻最为帅气 They look their best at this very moment
自己也清楚这点 and they know it.
母松鸡的条件是有型 She'll be looking for style.
还要耐力好 And stamina.
很好 Very nice.
牠也不错 He's not bad either.
选择多得眼花撩乱 The choice is bewildering.
但由于不分轩轾 But without a clear winner
舞池上演了全武行 fights break out on the dance floor.
睪固酮浓度破表 With all this testosterone flying around
母松鸡渐渐失去兴趣 she's losing interest.
比起奖赏 牠们似乎比较想打架 They seem to want the fight more than the prize.
雄松鸡得拿出更好的表现才行 The males need to up their game.
到了六月 By June
在不会西沉的太阳下 under a sun that no longer sets...
最难缠的积雪也会融去 露出翠绿的草地 even the most stubborn snow melts away to reveal lush grasslands.
(安克雷奇)
新生命改变冰雪北境的面貌 New life transforms the Frozen North.
这是美洲最大的野生动物保护区 This is America's largest wildlife refuge
三万平方哩的阿拉斯加大地 30,000 square miles of Alaska.
北极保护区 The Arctic Refuge.
在夏季 有一种动物称霸这片平原 In summer, one animal dominates these plains.
驯鹿 Caribou.
你也许在传说中听过牠们 You might know them as reindeer.
驯鹿居无定所 追着撤退的融雪 They're nomads, following the retreating snowmelt
有时跟着走上一千哩 sometimes for 1,000 miles
是世上最长途的陆上迁徙 the longest land migration in the world.
数百年来 每年夏天 Every summer, for centuries
驯鹿都会来此 生下小鹿 caribou have been coming here to have their calves.
这头小公鹿才三周大 This little male is only three weeks old.
但已经能跑得比奥运短跑选手还快 But he can already run faster than an Olympic sprinter.
认错妈妈是常有的事 It's easy to lose track of whose mom is whose.
在这里想探索 Wanting to explore
可能会惹上麻烦 can get you into trouble around here.
跟不上鹿群 Anyone who can't keep up with the herd
就会被丢下 will be left behind.
但驯鹿独特的叫声与气味 But their unique calls and scent
代表通常能找到彼此 usually mean they can find each other.
等到冬天 小鹿就能独立了 Come wintertime, he will be independent.
但在那之前 妈妈就是牠的全世界 But until then, Mom is his whole world
不管妈妈是否乐意 whether she likes it or not.
随着鹿群每天啃遍一千吨的冻原青草 As the herd eat their way through more than 1,000 tons of tundra grasses every day
牠们向西穿越沿岸平原 they move further west across the coastal plains.
但饥饿驱使牠们走向危机 But hunger is driving them towards danger.
一度覆盖北境的积雪 The snow that blanketed the Frozen North
已然化作数十亿加仑雪水 now descends from the mountains
冲下山 as billions of gallons of meltwater
集结为汹涌的洪流 channeled into raging torrents
阻断驯鹿的路线 cutting across the caribous' path.
这些河川的水深与湍急程度更甚以往 These rivers are deeper and faster than ever before.
而草场在对面 And the feeding grounds lie on the other side.
小驯鹿还没准备好渡河 This crossing is more than a young calf is ready for.
但渡河攸关存亡 But survival depends on it.
水流让驯鹿猝不及防 The current takes them by surprise
将小驯鹿给冲走了 sweeping him off his feet.
母亲现在得做出艰难抉择 This mother now has a tough choice to make.
阿拉斯加北极保护区的河岸上 On the riverbanks of Alaska's Arctic Refuge
这头驯鹿母亲在河中寻找失踪小鹿的踪影 this caribou mother scans the water for any sign of her missing calf.
鹿群要继续前进了 The herd is moving on.
母鹿跟随鹿群的本能太强大了 Her instinct to follow them is just too strong.
下游处 小驯鹿还活着 Downriver, the calf is still alive.
牠斗志坚强 He has a fighting spirit
但是累坏了 but he's exhausted.
到处都找不到妈妈 Mom's nowhere to be seen.
鹿群慢下脚步进食 As the herd slows down to feed
走失的小鹿只能努力赶上 all a lost calf can do is try to catch up.
母驯鹿很少收养走失或丧母的幼鹿 Female caribou rarely adopt lost or orphaned young.
妈妈认出熟悉的叫声 Mom recognizes a familiar bleating.
终于团圆了 Reunited.
在极北地区必须赶快长大成熟 You have to grow up quickly in the Far North.
小驯鹿将牢记这些古老的路线 These ancient routes will soon be ingrained in his memory.
牠注定要漫步这片广大的美洲冻原 His destiny is to endlessly wander this vast American tundra.
夏季暖了北境 As summer warms the North
数百条上涨的河川挟带陆地的土壤与养分 hundreds of these swollen rivers carry soil and nutrients
流向大海 from the land to the sea.
对某些生物而言 这是食物丰足的时期 And for some, this becomes a time of plenty.
七月 阿拉斯加偏远的圆岛上 In July, on Alaska's isolated Round Island
风中传来奇怪的声音 a strange sound is carried on the wind.
仔细听听 Just listen.
这道意外的歌声 This is the surprising song...
由公海象献唱 of male walruses
这是求偶的鸣声 known as chiming.
从海象喉咙内的气囊发出 It's made by pockets of air in their throats.
通常在冬天的繁殖季歌唱 以博取母海象芳心 Usually, they sing to impress females during the winter mating season.
但放眼望去没半只母海象 But there's no ladies in sight.
这样可能正合母海象的意 Which probably suits the ladies just fine.
在阿拉斯加温暖的夏夜 On Alaska's warm summer evenings
也许这只是牠们专属的摇篮曲 perhaps this is nothing more than their very own lullaby.
对海象来说 短暂夏季最重要的就是耍废 For walruses, the short summers are all about downtime.
但阿拉斯加内陆的浅水处 But in the shallows of Alaska's mainland
可没时间休息 there is no time to rest.
粉红鲑在竞赛起跑线聚集 Pink salmon gather at the starting line of a race
即将挑战极限 that will test them to their limits.
受到无从忽视的冲动驱使 Driven by an urge they cannot ignore
鲑鱼来到自己当初诞生的河流口 salmon arrive at the entrance of the very same stream in which they were born.
过了两年 轮到牠们繁衍了 Now, two years later, it's their turn to breed
总共两亿条鲑鱼 all 200 million of them.
这只母鱼肚中有至少两千颗卵 This female is carrying at least 2,000 eggs.
回到自己诞生的相同地点 Returning to the same spot in which she was born
牠的后代最有希望生存 will give her offspring the best chance of survival.
但牠前方 But ahead of her
有着要命的障碍赛道 lies a killer assault course.
若不成功 She must succeed
便成仁 or die trying.
阿拉斯加 威廉王子湾 Prince William Sound, Alaska.
潮水迅速退去 As the tide races out
无数粉红鲑都在等待 countless pink salmon are waiting.
牠们产卵场的气味越来越浓烈 The scent of their spawning grounds grows stronger.
现在要赶紧冲过浅滩 Now it's a race to cross the shallows
以免被潮水困住 before the tide cuts them off.
稍有闪失就没戏唱了 One wrong turn and it's game over.
对海鸥来说 For gulls
盛宴正要开动 the banquet has begun.
而且还可以挑剔 They can be picky at this stage...
只选最鲜嫩的鱼肉 only selecting the most tender flesh.
这只母鱼铸下大错 This female has made a serious error
要害暴露无遗 and is now dangerously exposed.
但牠的决心似乎让攻击者很困惑 Her determination seems to confuse her attacker.
一切才刚开始 This is only the beginning.
每只鲑鱼都来日不长了 Every salmon is now on borrowed time.
从现在起 牠们几乎不进食也不休息 From here on out, they barely eat or rest
奋力逆流而上 as they forge upstream.
这趟旅程代价庞大 This journey takes a grim toll
鲑鱼的身体开始衰竭耗损 as their bodies begin to shut down and decay.
有些速度较快一些 Some faster than others.
最后 牠们抵达产卵场 Finally, they arrive at their spawning grounds
但事情还没完 but it's not over yet.
这条母鱼需要建造浅浅的窝 This female needs to construct a shallow nest
也就是所谓的产卵巢 known as a redd.
牠拨走细小的沉积物 She flicks away fine sediment
防止鱼卵被闷死 to prevent her eggs from being smothered.
牠会誓死捍卫巢穴不受其他母鱼侵袭 She will fiercely defend her nest from other females.
现在某些公鱼看起来活像丧尸 By now, some males look like The Swimming Dead.
成了殭尸鲑鱼 They're zombie salmon.
急着在死前交配 Desperate to mate before they die.
有点恶心 Kind of gross.
母鱼历经千辛万苦 After all she's been through
才不接受不够完美的对象 she's not going to settle for anything less than perfect.
公鱼会竭尽所能让更多窝的卵受精 Males fertilize eggs in as many redds as possible
但母鱼只有一次机会 but this will be her only chance.
牠准备好了才会产卵 She will only release her eggs when she's ready.
这一刻将成为牠的定局 It's the moment that will seal her fate.
跟母亲在同一段河域产卵并死去 Spawning and dying on the same stretch of river as her mother
是母鲑鱼的宿命 is a female salmon's destiny.
尽管牠们的旅程在此结束 Though their journey ends here
这些鲑鱼留下的数百万鱼卵 these salmon leave behind millions of eggs
将成长为下一代 that will become the next generation.
生命轨迹 Life...
由季节更迭决定 dictated by the seasons.
仅过了两个月 冬季再度降临 In just two months, winter returns.
有些动物启程 南下跋涉 Some begin the long trek south.
其他则在窝里待上数个月 Others surrender to many months in the den.
更有某些动物在这片冰天雪地中 But there are those who are perfectly at home
活得很自在 in this snowbound world.
这个 A place
充满魔力的世界 full of magic.
在冰雪北境 有一件事是肯定的 One thing is certain here in the Frozen North...
没有什么事 nothing stays the same
能恒常不变 for long.
待续
谢谢观赏