instead of flying south to warmer climes. 而一直坚守在这里经受着北方寒冬的考验

133. but this bleak wilderness remains locked in ice.
     但这片荒凉的无人区仍然是冰封的天地
134. Eider ducks break the silence.
     绒鸭的到来打破了这里的平静
135. They have stayed here, braving the northern winter,
     绒鸭没有迁徙到温暖的南方
136. instead of flying south to warmer climes.
     而一直坚守在这里经受着北方寒冬的考验
137. Flocks 40,000 strong sweep across the frozen wastes.
     4万只绒鸭飞越这一片冰天雪地的荒野
138. They all have the same goal, a polynya,
     它们都有相同的目标--冰间湖（冰穴）
139. a permanent hole in the sea ice, kept open throughout the winter by strong ocean currents.
     冰间湖是结冰的海洋上永久性的洞孔 因为有强大的洋流使它们冬天也不会冰封

来自《行星地球 第一季 第六集 Planet Earth S01E06 冰雪世界》第 136 行