Unlike Antarctica, the Arctic is a vast frozen sea surrounded by land. Here winter is coming to an end but this bleak wilderness remains locked in ice. Eider ducks break the silence. They have stayed here braving the northern winter, instead of flying south to warmer climes. Flocks, 40,000 strong, sweep across the frozen wastes. They all have the same goal, a polinear, a permanent hole in the sea ice kept open throughout the winter by strong ocean currents. This unusual duck pond provides an overnight sanctuary and when day breaks a rare chance to feed. Just ten metres beneath the ice, the sea floor is carpeted with dense mussel beds. These can only be reached during a brief lull in the currents. The ducks must quickly prise the mussels free before the tide starts to turn.


与南极不同，北极是一片被陆地包围着的冰海。现在冬天快结束了，不过原野仍然是冰雪覆盖。最先打破这里寂静的是欧绒鸭，它们没有飞到较温暖的南方，而是坚守在这里度过了冬天。在冰雪的原野上，有四万只欧绒鸭在展翅飞翔。欧绒鸭在寻找一个目标，即北极地区永不封冻的冰洞，因为那里整个冬天都有湍急的洋流在流动。这个不同寻常的池塘给它们提供了过夜的好地方，天亮之后又是它们觅食的好去处。在冰面下十米处的海床上，有大量的贻贝，绒鸭只能在洋流暂时平静的时候才能潜到水底，而且要在潮水开始回流之前尽快地抓住贻贝。