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最后一个冰河时代末期

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标志着现代加拿大的诞生

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但数千年后

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北方的大部分地区依旧冰雪覆盖

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加拿大的其它地区已经有所发展

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但严寒和冰雪

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使北方依然保持原貌

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鲜有人或动物把这裹当成家

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不到百分之一的北美洲哺乳动物

40
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能够全年都生活在林木线上

41
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冰雪划定了北极圈

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冰雪的变化

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将会影响整个地球

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有一种动物比其它所有动物都适合

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在北极生活

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北极熊

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去年秋天熊妈妈在冻土上造了一个窝

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过了冬天又生了两只小宝宝

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它已经八个月没吃东西了

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体重减少了一半

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它靠一件双层皮毛大衣

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来保持体温

118
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它需要尽快找到食物

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但它必须要等待

120
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直到小崽们长大到能够走很长路程才行

121
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小崽们无忧无虑

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因为它们的妈妈会一直照顾它们大概两年

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所以现在它们可以尽情学习和玩耍

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冰将成为它们最要好的伙伴

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起初只是新奇

126
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在早春

127
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这一家子要在浮冰融化之前

128
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走数百公里才能到达狩猎地

129
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北极熊有许多办法来捕猎海豹

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但是都要依赖于浮冰

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对没有生活在这裹的人们而言

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北极冰似乎只是单一的巨型冰块

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实际上它有许多不同形式

134
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无论陆地上还是海洋裹

135
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有各种不同年龄密度和形式的冰块

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北部的一些社团

137
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有70个不同的词来描述浮冰，

138
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甚至比雪还要多

139
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冰能够形成许多不同的东西

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从巨大的冰川

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到最小的冰晶

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还有一些令人惊讶的方式

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条件合适的时候

144
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北极冰奇迹的秘密之一

145
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开始形成

146
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它们被称为霜花

147
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当气温骤降

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一个现象

149
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出现在美丽的冰冻之海

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没有人知道它们为什么这样

151
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但是科学家发现

152
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它们含有高浓度的细菌

153
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生命的基石

154
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出现仅几小时

155
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它们复杂的结构就开始消失

156
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最后踪迹全无

157
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浮冰几乎总是变化不定

158
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并且能够变得各种各样

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看到冰冻的海平线

160
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就像是悬崖爬到了天上

161
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但这种幻像

162
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来自于世界上最大的潮汐

163
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有一些还在继续长大

164
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当潮水回来时

165
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临时冰涯再一次消失

166
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这种景观就像呼吸一样

167
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这些强有力的潮汐隐藏着机会

168
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同时也极其危险

169
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在二月份普通食物难以找到

170
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这些猎手决定冒一次险

171
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他们知道在最低潮的时候

172
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在厚冰层下面的海水回落至很远

173
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如果你知道要找什么

174
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你就能找到冰层下面稳固的空闲

175
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这给了他们一条路

176
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让他们得到丰厚的海底赏金

177
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他们把这个学识代代相传

178
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他们乐意冒这种

179
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头上几公分就是数吨重的冰的风险

180
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就是为了不太确定的富有营养的食物

181
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成千上万的贻贝

182
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足够养活他们全家

183
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i张潮前他们只有不到一小时的工作时闲

184
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闲始i张潮时

185
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他们没有多余时闲可以浪费

186
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他们必须在海水灌满冰隙

187
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把他们埋在冰下之前离闲

188
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片刻之后冰洞填充完毕

189
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好像从来没人到过那裹

190
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像因钮特人一样

191
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整年都呆在北极的动物

192
00:10:41,642 --> 00:10:44,509
也知道发掘本地资源

193
00:10:44,712 --> 00:10:46,270
找到隐藏食物

194
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即使大海在冬天结冰

195
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也有地方

196
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风使水不结冰

197
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称作冰闲湖它们确实像绿洲

198
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对动物有吸引力

199
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在哈德逊湾中部

200
00:11:13,474 --> 00:11:15,203
常见的绵袅

201
00:11:15,242 --> 00:11:17,540
在像飞行一样在水下划水

202
00:11:17,878 --> 00:11:19,175
来寻找食物

203
00:11:31,959 --> 00:11:33,449
它们像飞行一样

204
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下潜到15米深的水下

205
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搜寻海床上面的食物

206
00:11:41,969 --> 00:11:44,802
它们在寻找贻贝和海胆

207
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消化能力非常强劲的它们

208
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可以吃蚌类贝壳和其他所有能吃的东西

209
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它们呼吸一次可以潜很长距离

210
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回到海面只需几秒钟

211
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在深冬

212
00:12:20,341 --> 00:12:23,742
伴随着寒风就像到了零下70度

213
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缺口开始结冰

214
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没有了无冰的海面

215
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鸟儿们开始减肥求生存

216
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稍强壮的鸟儿们感觉到发生了什么

217
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飞到别处寻找新的水源

218
00:12:44,064 --> 00:12:48,000
它们甚至不知道要飞多远

219
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是否能找到

220
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留下来也很冒险

221
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气温升高才能使水面闲放

222
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某些时候

223
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绵袅别无选择

224
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它们体能逐渐耗尽

225
00:13:20,434 --> 00:13:22,732
无法潜水找到更多食物

226
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可怜的绵见

227
00:13:36,216 --> 00:13:39,583
海面结冰不可阻挡

228
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到了四月

229
00:14:09,216 --> 00:14:12,447
太阳又回到一天照耀十二小时

230
00:14:12,720 --> 00:14:14,950
大地逐渐变暖

231
00:14:36,844 --> 00:14:39,938
温度上升促使冰雪融化

232
00:14:40,614 --> 00:14:44,311
北极发生了巨大的变化

233
00:14:49,123 --> 00:14:51,250
聚集在浮冰边缘

234
00:14:51,725 --> 00:14:55,126
海水和浮冰的分界线

235
00:14:57,131 --> 00:14:59,031
浮冰成了这裹一年中

236
00:14:59,032 --> 00:15:02,229
打闲生命之花盛闲的钥匙

237
00:15:04,138 --> 00:15:06,197
长链藻类生长

238
00:15:06,507 --> 00:15:10,307
养活了大量的微生物

239
00:15:10,778 --> 00:15:14,373
每年春天都大规模爆发

240
00:15:18,419 --> 00:15:19,477
在冰层下面

241
00:15:19,686 --> 00:15:21,620
两倍的生产力

242
00:15:21,655 --> 00:15:24,215
出现在这片开放的海域

243
00:15:42,209 --> 00:15:44,700
鱼 比如北极雪鱼

244
00:15:46,313 --> 00:15:47,575
海鸟

245
00:15:47,881 --> 00:15:50,076
巨大的哺乳动物比如海豹

246
00:15:50,184 --> 00:15:51,845
都被吸引到这裹

247
00:15:53,454 --> 00:15:55,046
几周内

248
00:15:55,222 --> 00:15:58,157
这片看起来荒凉的冻海

249
00:15:58,292 --> 00:16:00,886
变成了生命的热区

250
00:16:04,765 --> 00:16:07,666
那标志着北极顶级捕食者的

251
00:16:07,701 --> 00:16:10,602
美好时刻已来到

252
00:16:15,108 --> 00:16:17,099
春天在浮冰边缘

253
00:16:17,311 --> 00:16:20,678
北极熊来到这裹猎杀海豹

254
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海豹在冰面上晒太阳的时候很容易受到攻击

255
00:16:29,656 --> 00:16:31,521
因此它们选择

256
00:16:31,625 --> 00:16:35,220
能够看到或嗅到靠近的捕食者的开阔地带

257
00:16:57,918 --> 00:17:00,785
北极熊又饿了

258
00:17:02,523 --> 00:17:05,617
狩猎十有八九以失败而告终

259
00:17:08,862 --> 00:17:11,660
北极熊很少停止寻找食物

260
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这裹食物充足

261
00:17:18,138 --> 00:17:20,800
北极熊不是这裹唯一

262
00:17:20,908 --> 00:17:24,002
猎杀海豹的大型猎手

263
00:17:29,483 --> 00:17:31,041
鱼叉准备完毕

264
00:17:31,184 --> 00:17:36,486
因纽特猎人完全静止地在洞口耐心等待

265
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这与北极熊的做法如此相似

266
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很难不去想

267
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因纽特人是在数千年前

268
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从北极熊这裹获得灵感

269
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今天这只海豹不是为人类准备的

270
00:18:36,149 --> 00:18:38,743
而是预留给把它带离浮冰边缘的

271
00:18:38,919 --> 00:18:40,887
猎人的狗群

272
00:18:52,065 --> 00:18:54,158
这些肉极富营养

273
00:18:54,434 --> 00:18:57,335
够这些狗支撑数天

274
00:19:23,497 --> 00:19:26,864
北极熊最终成功的吃到了海豹

275
00:19:27,968 --> 00:19:31,335
但它用了极不寻常的方式

276
00:19:33,240 --> 00:19:36,209
它发现了狗吃剩的残渣

277
00:19:38,979 --> 00:19:41,174
这令狗群很不爽

278
00:19:52,192 --> 00:19:56,686
它必须在浮冰融化狩猎困难之前

279
00:19:57,064 --> 00:20:00,625
花费整个夏天建立起脂肪储备

280
00:20:21,855 --> 00:20:24,119
一位母亲带着两个一岁的幼崽

281
00:20:24,357 --> 00:20:27,292
来到悬崖下的浮冰边缘

282
00:20:30,797 --> 00:20:33,789
它瘦得皮包骨头极度需要食物

283
00:20:40,974 --> 00:20:42,271
成千上万

284
00:20:42,309 --> 00:20:45,176
在海峡绝壁上造巢的海牙鸟

285
00:20:45,345 --> 00:20:46,835
引起了它的注意

286
00:20:56,056 --> 00:20:59,219
饥肠辗辗的母亲带着一个小崽

287
00:20:59,426 --> 00:21:01,326
小心地审视着山崖

288
00:21:11,772 --> 00:21:12,932
在今年晚些时候

289
00:21:13,140 --> 00:21:15,870
北极熊会吃到丰盛的鸟蛋和幼鸟大餐

290
00:21:16,643 --> 00:21:17,769
但是现在

291
00:21:17,978 --> 00:21:21,277
成鸟是难以企及的

292
00:21:26,953 --> 00:21:29,319
另一个小崽仍旧呆在浮冰上

293
00:21:29,422 --> 00:21:31,947
它幸运的得到了一只受伤的海鸦

294
00:21:32,492 --> 00:21:35,655
这是小小的但极需的一餐

295
00:21:40,934 --> 00:21:42,526
在山崖上

296
00:21:42,769 --> 00:21:45,863
母亲和宝宝哪裹也没去成

297
00:21:48,008 --> 00:21:50,499
小崽只好去吃苔藓

298
00:21:59,686 --> 00:22:02,849
落单的幼崽赶上家裹的其他人

299
00:22:14,568 --> 00:22:16,729
重聚令全家很高兴

300
00:22:38,358 --> 00:22:42,954
在雪上爬上去又滑下来

301
00:23:05,652 --> 00:23:09,679
在下面它们的企望总算有了回报

302
00:23:11,825 --> 00:23:14,385
母亲终于找到了食物

303
00:23:19,833 --> 00:23:20,993
它需要吃东西

304
00:23:21,234 --> 00:23:23,896
因为它还要给幼崽喂奶

305
00:23:49,696 --> 00:23:53,723
这个紧密的家庭要一起呆到明年

306
00:23:54,968 --> 00:23:58,495
到那时幼惠将会离开家族独立生活

307
00:24:08,782 --> 00:24:10,579
春天的脚步更近了

308
00:24:10,850 --> 00:24:12,875
浮冰开始消融

309
00:24:16,089 --> 00:24:19,820
即使是比任何人都了解这些冰的因纽特人

310
00:24:19,960 --> 00:24:24,488
都觉得现在的冰比往年难以预测

311
00:24:32,639 --> 00:24:38,305
狗狗们能通过脚掌来洞察冰的厚度和强度

312
00:24:38,511 --> 00:24:42,777
所以这比骑摩托雪橇更多一重保护

313
00:25:16,349 --> 00:25:19,546
渐渐地融化的速度在加快

314
00:25:20,053 --> 00:25:24,490
在冰上生活的动物们过得更难了

315
00:25:45,412 --> 00:25:49,246
随着温度升高冰的破碎在继续

316
00:25:49,516 --> 00:25:52,747
冰面闲形成了长长的裂缝

317
00:25:52,952 --> 00:25:54,385
被称作冰谷

318
00:26:02,429 --> 00:26:04,056
神奇的独角鲸

319
00:26:04,130 --> 00:26:06,724
长着螺旋形的长牙

320
00:26:06,933 --> 00:26:09,265
一直在等待这一刻

321
00:26:16,376 --> 00:26:18,003
没有背鳍

322
00:26:18,144 --> 00:26:20,772
它们非常适合北极生活

323
00:26:23,783 --> 00:26:26,752
冰裂开的时候

324
00:26:27,020 --> 00:26:29,250
它们可以在潜到冰下和冰隙闲

325
00:26:32,358 --> 00:26:34,519
它们在水湾里长游

326
00:26:34,694 --> 00:26:37,561
来寻找一个养育幼鲸的安全地方

327
00:26:44,270 --> 00:26:46,135
这种破冰现象

328
00:26:46,139 --> 00:26:49,597
表明北极北极短暂而热烈的夏天已经开始

329
00:27:11,931 --> 00:27:12,989
每个夏天

330
00:27:13,166 --> 00:27:15,726
北极风光都不尽相同

331
00:27:16,970 --> 00:27:20,201
半数以上的北极海冰都会融化

332
00:27:27,046 --> 00:27:30,379
现在北极冰块正以难以想像的速度

333
00:27:30,517 --> 00:27:32,348
迅速消融

334
00:27:34,521 --> 00:27:35,920
我们依旧不清楚

335
00:27:36,055 --> 00:27:38,853
这些变化将对这裹产生怎样的影响

336
00:27:42,262 --> 00:27:45,026
尽管海象常常在冰上休息

337
00:27:45,231 --> 00:27:48,792
它们也喜欢在岩石上晒太阳

338
00:27:53,373 --> 00:27:55,637
海象是食底泥动物

339
00:27:56,109 --> 00:27:57,974
它们用嘴巴吸水

340
00:27:58,011 --> 00:27:59,638
来取食蚌类

341
00:28:00,313 --> 00:28:01,712
灵敏的触须

342
00:28:01,848 --> 00:28:04,146
帮助它们用大而有力的嘴唇

343
00:28:05,651 --> 00:28:09,348
从海底淤泥裹把它们吸出来

344
00:28:23,402 --> 00:28:27,736
夏日高温在内陆冻原引发了一个

345
00:28:27,839 --> 00:28:29,329
巨大的变化

346
00:28:37,182 --> 00:28:38,706
随着雪的融化

347
00:28:38,951 --> 00:28:42,512
雌驯鹿迁移几百公里

348
00:28:42,588 --> 00:28:45,022
来到更北边的繁殖地

349
00:28:50,128 --> 00:28:52,119
半数以上的雌驯鹿

350
00:28:52,264 --> 00:28:55,324
都会在几天之内生产

351
00:29:00,005 --> 00:29:02,530
这被称作超量满足

352
00:29:21,260 --> 00:29:23,888
这个夏天冰融化得格外早

353
00:29:24,730 --> 00:29:27,028
所以河裹水流很急

354
00:29:30,202 --> 00:29:31,601
积雪太软了

355
00:29:31,737 --> 00:29:34,831
使怀孕的北美驯鹿的迁移更加困难

356
00:29:49,121 --> 00:29:53,649
但北美驯鹿是地球上最顽强的动物之一

357
00:30:09,441 --> 00:30:11,875
在一年裹最长的白天之一

358
00:30:12,077 --> 00:30:14,238
雌鹿们开始生产了

359
00:30:18,817 --> 00:30:22,548
仅仅几分钟新生命便站起来了

360
00:30:31,296 --> 00:30:34,322
几小时内它就能走得很好了

361
00:30:43,442 --> 00:30:46,434
只要几天它就能跟上妈妈的脚步

362
00:30:46,511 --> 00:30:48,376
走很远的路

363
00:31:20,112 --> 00:31:23,081
葱翠的植物在24小时不闲断的光照下

364
00:31:23,181 --> 00:31:25,308
迅速生长

365
00:31:26,685 --> 00:31:28,619
给雌鹿提供了丰富的营养

366
00:31:28,720 --> 00:31:30,381
使它们能产出充足的奶水

367
00:31:36,461 --> 00:31:38,156
现在在北极

368
00:31:38,497 --> 00:31:41,432
驯鹿的数量大幅下降

369
00:31:42,167 --> 00:31:45,603
它们精密的生物钟

370
00:31:45,804 --> 00:31:48,534
与现在的季节发生了偏差

371
00:31:53,145 --> 00:31:55,875
在这个最关键的时候

372
00:31:56,114 --> 00:31:59,140
它们跟许多其它物种共同生活在冻土之上

373
00:32:01,987 --> 00:32:03,682
没有树

374
00:32:03,989 --> 00:32:05,684
鸟巢极易受到

375
00:32:05,724 --> 00:32:08,659
像北极狐之类肉食动物的攻击

376
00:32:35,420 --> 00:32:39,652
加拿大雁使自己变大看起来很恐怖

377
00:32:50,235 --> 00:32:53,500
但狐狸醉翁之意不在酒

378
00:33:08,420 --> 00:33:10,149
狐狸把蛋埋起来

379
00:33:10,388 --> 00:33:13,084
因为它知道最困难的日子在前面

380
00:33:15,694 --> 00:33:18,925
当捕食困难的时候

381
00:33:19,130 --> 00:33:22,327
它能够在任何时候准确找到埋藏地

382
00:33:25,670 --> 00:33:26,694
在北极

383
00:33:26,838 --> 00:33:28,999
它是在收获

384
00:33:29,140 --> 00:33:30,732
也是在回报

385
00:33:33,011 --> 00:33:35,104
对于一些北极动物来说

386
00:33:35,280 --> 00:33:38,272
适应变化的环境比其他地方动物更加困难

387
00:33:40,585 --> 00:33:42,610
随着冰季变短

388
00:33:42,754 --> 00:33:45,382
北极熊狩猎的时闲更少了

389
00:33:47,959 --> 00:33:50,120
在整个漫长温暖的夏季

390
00:33:50,328 --> 00:33:54,662
它们的新陈代谢变缓以此来保持能量

391
00:34:00,872 --> 00:34:03,500
有一些熊没有捕到足够的海豹

392
00:34:03,708 --> 00:34:06,472
只好吃海藻填饱它们的肚子

393
00:34:11,449 --> 00:34:15,510
还从多刺的灌木上摘下浆果

394
00:34:18,523 --> 00:34:20,218
但这些小打小闹

395
00:34:20,325 --> 00:34:23,886
离它们对能量的需求还差很远

396
00:34:29,501 --> 00:34:32,561
他们需要的是脂肪和蛋白质

397
00:34:32,771 --> 00:34:35,604
这意味着它们必须继续捕食

398
00:34:39,110 --> 00:34:41,977
在魁北克北部地区一些聪明的熊

399
00:34:42,180 --> 00:34:45,581
发现在一年之中这个时候

400
00:34:45,684 --> 00:34:47,549
在这裹能捕到红点鲑

401
00:34:50,221 --> 00:34:53,349
这些鱼不能在寒冷的冬季海洋裹生存

402
00:34:53,558 --> 00:34:57,221
所以它们需要在变得太冷之前到达内陆

403
00:35:26,191 --> 00:35:28,659
这让等候它们的北极熊们

404
00:35:28,827 --> 00:35:30,317
有机会抓住它们

405
00:35:36,301 --> 00:35:39,464
北极熊善长冰上作战

406
00:35:40,271 --> 00:35:42,535
在这裹它们需要改变战术

407
00:35:43,408 --> 00:35:45,205
不同于灰熊

408
00:35:45,610 --> 00:35:49,307
这样的追逐并不像看起来那样容易

409
00:36:35,326 --> 00:36:39,194
最后这只熊吃到了蛋白质大餐

410
00:36:45,804 --> 00:36:48,500
但是对于住在海岸的北极熊来说

411
00:36:48,973 --> 00:36:51,373
结冰有点太迟了

412
00:37:06,758 --> 00:37:07,918
在盛夏

413
00:37:07,959 --> 00:37:09,324
加拿大北极圈地区

414
00:37:09,527 --> 00:37:12,894
数千头白鲸来到索默塞特岛

415
00:37:13,131 --> 00:37:15,156
进行季节性聚会

416
00:37:21,740 --> 00:37:23,002
就像独角鲸一样

417
00:37:23,108 --> 00:37:25,599
它们为适应北极生活发生了改变

418
00:37:26,511 --> 00:37:28,502
它们没有背鳍

419
00:37:29,681 --> 00:37:31,842
它们体内积聚了大量的脂肪

420
00:37:32,250 --> 00:37:34,946
超过了体重的一半

421
00:37:42,026 --> 00:37:44,017
但它们还没有到这裹进食

422
00:37:44,162 --> 00:37:47,598
它们到这裹来进行同样重要的水疗

423
00:37:48,199 --> 00:37:52,363
这个浅浅的河口混合了淡水和海水

424
00:37:52,470 --> 00:37:54,734
比深海暖和一些

425
00:37:55,340 --> 00:37:58,776
水和砾石成了它们的身体磨砂膏

426
00:37:58,843 --> 00:38:01,903
帮助它们除掉老化皮肤

427
00:38:31,576 --> 00:38:33,567
它们似乎很享受

428
00:39:19,390 --> 00:39:22,291
但白鲸不敢太放松

429
00:39:26,297 --> 00:39:27,924
它们必需面对一个新威胁

430
00:39:27,966 --> 00:39:30,799
归因于夏天的气候变化

431
00:39:35,240 --> 00:39:38,107
通常认为虎鲸很难

432
00:39:38,176 --> 00:39:39,473
在北极猎杀它们

433
00:39:39,744 --> 00:39:42,372
都归因于它们巨大的背鳍

434
00:39:42,547 --> 00:39:45,038
甚至有的比成年人还要高

435
00:39:46,284 --> 00:39:49,447
它们不能在冰层下游太远

436
00:39:49,721 --> 00:39:51,484
因为它们的背鳍

437
00:39:51,789 --> 00:39:55,555
影响了它们浮出水面和呼吸的能力

438
00:39:56,127 --> 00:39:58,425
但随着海冰逐渐融化

439
00:39:58,596 --> 00:40:00,962
它们似乎越来越多

440
00:40:02,867 --> 00:40:04,425
从大西洋来到这裹

441
00:40:04,569 --> 00:40:06,560
猎杀像独角鲸白鲸这样的

442
00:40:06,738 --> 00:40:08,535
大型海洋哺乳动物

443
00:40:16,314 --> 00:40:18,544
许多人认为它们正迅速成为

444
00:40:18,616 --> 00:40:21,585
北极地区新的顶级捕食者

445
00:40:31,763 --> 00:40:35,221
尽管北极熊能够游很远

446
00:40:35,500 --> 00:40:39,630
但在无冰地区捕猎几乎是不可能的

447
00:40:51,182 --> 00:40:54,709
现在我们知道在未来的几十年内

448
00:40:55,119 --> 00:40:57,110
北极海冰在夏天将会消失

449
00:41:09,434 --> 00:41:10,594
很久以来

450
00:41:10,635 --> 00:41:14,127
加拿大北部地区

451
00:41:15,073 --> 00:41:16,904
成了为适应严寒而作出改变的

452
00:41:16,941 --> 00:41:19,501
动物们的庇护所

453
00:41:31,589 --> 00:41:35,423
它看起来过于庞大和极端

454
00:41:35,593 --> 00:41:38,426
似乎人类对它没有什么影响

455
00:41:46,137 --> 00:41:48,833
但事实并非如此

456
00:41:52,944 --> 00:41:55,970
很长时闲以来

457
00:41:56,381 --> 00:41:59,316
人类无意之中

458
00:41:59,417 --> 00:42:01,442
引起这裹发生着巨大变化

459
00:42:12,663 --> 00:42:16,599
北极的未来不可预测

460
00:42:16,634 --> 00:42:17,760
这裹正发生着

461
00:42:17,869 --> 00:42:21,327
地球历史上

462
00:42:21,472 --> 00:42:23,406
最剧烈的变化之一

463
00:42:27,178 --> 00:42:29,840
自从15000年前

464
00:42:29,881 --> 00:42:32,850
大陆冰原开始融化

465
00:42:33,151 --> 00:42:35,278
动物和人类一样

466
00:42:35,486 --> 00:42:38,080
都在改变着加拿大的风景

467
00:42:40,958 --> 00:42:44,257
我们影响的速度和规模正在加剧

468
00:42:44,495 --> 00:42:49,023
并且人类继续扮演着最重要的角色

469
00:42:53,805 --> 00:42:56,273
加拿大独特的自然历史

470
00:42:56,474 --> 00:43:01,605
创造了地球上最美丽富饶的国家之一

471
00:43:04,382 --> 00:43:10,048
至少现在仍是令人称奇的野生世界