And we haven't even gotten into the whole mercury thing yet, where migratory Pelagic fish like tuna absorb toxic metals.

我们还没说到有害物质呢，洄游的大洋性鱼类，比如金枪鱼会吸收有害金属。

The Antarctic seas serve as a refuge for an extremely large number of migratory fish that flee from storms in the subpolar zones, in truth only to slide down the gullets of porpoises and seals.

南极海水是大多数候鱼的藏身处，它们躲避纬度较低水层的风暴，转移到这边来。可是它们往往又掉到海豚和海豹的嘴里去了。