It may look like fun, but this is serious training for the task ahead. There's no food on the slopes and the family will need to head out across the frozen sea before the mother's milk runs dry. Two weeks later they're ready. Out on the sea ice the female can hunt for seals but it'll take all her mothering skills to keep her cubs safe in this dangerous world of ice. The annual melt has begun. This is a challenging time for the bear family. One out of every two cubs do not survive their first year out on the ice. As the sun's influence increases, the sea ice seems to take on a life of its own. Glacial melt waters pour from the land mingling with the sea and speeding up the thaw. 看起来好像很好玩,但它是一种严肃的训练是为了完成未来任务所必须的,它们一家必须在妈妈还有奶的时候,快些走过这片封冻的地带。两周之后,它们到达了可以狩猎的地方,母熊可以在冰面上捕到海豹,但要在这个危险的冰雪世界中,同时保护好自己的孩子,它必须使出浑身解数。一年一度的冰雪融化开始了对于北极熊一家来说,这是一个缺吃少喝的时期,在第一年里每两只小熊只有一只能存活下来,太阳的热力一天天增加,海面上的冰似乎也有了生命,陆地冰川融化的雪水流了下来汇入海中,加速了冰的融化速度。