Arctic cod spend winter beneath the sea ice.
北极鳕鱼躲在海冰下面过冬。
Right across the Arctic Ocean, the fish play a major part in the food chain and bring rich pickings for all the marine mammals.
在整个北冰洋这种鱼在食物链中占据着重要位置，为所有的海洋哺乳动物提供了丰富的食物。
As the ice melts, massive shoals gather along Greenland's west coast.
随着冰层融化大量的鱼群聚集在格陵兰岛西岸。
During the short summers of constant daylight, the Arctic Ocean burst into life.
在短暂的极昼夏日时光里，北冰洋迎来了生命的爆发期。
Millions of seabirds return to the Polar North to take advantage of the abundance of seafood.
几百万只海鸟飞回北极来享用这里丰富的海产。
The temperature of the water rarely rises above minus one degree Celsius, but the shallow seas of the Arctic are some of the earth's richest.
这里的水温很少上升到摄氏零下一度以上，但北极的浅海区却是地球上最富饶的海域之一。
These underwater life forms have made some remarkable adaptations to survive in the ice cold water.
这些水下生物对在冰冷的海水中生存已经显现出某些不同寻常的适应性。
They are the same temperature as the water that surrounds them.
它们拥有与周围海水相同的体温。
And their survival depends on preventing ice crystals from forming in their bodies.
而它们的生存是依靠防止自己体内形成冰晶体。
Many produce special proteins in their blood that act as antifreeze.
许多动物在自己血液里产生特殊的蛋白质来作为防冻剂。
In summer, the powerful nonstop rays of the sun create a bloom of phytoplankton and microscopic plant life.
夏季时强力而持续的太阳光照使浮游植物生长旺盛，而微生植物也很兴旺。
The phytoplankton trails the edge of the ice and can stretch for nearly fifty kilometers.
浮游植物沿着冰层的边缘生长，绵延可达近五十公里。
For a few short month each year, they provide huge quantities of food for billions of invertebrates.
每年在短暂的几个月时间里，它们为数十亿无脊椎动物提供了大量的食物。
These crustaceans are vital element in the arctic food chain.
这些甲壳类动物是北极食物链中的关键一环。
And they form a stable diet of an arctic giant.
它们也是一种北极巨兽的稳定食物。
A bowhead whale eats nearly two thousand kilos of crustaceans everyday.
一头弓头鲸每天要吃近两吨的甲壳类动物。
Weighing at over seventy thousand kilos, they can reach up to twenty meters of length.
它们体重可达七十吨以上体长可达二十米。