Somewhere, beneath the surface below, there is the food it must have. 水下某个地方一定有食物

266. How they find their way back across thousands of miles of open ocean,
     它们如何从1000英里外再次赶回
267. we still have no idea.
     仍然是个谜
268. A frigate soars.
     军舰鸟正在高飞
269. Somewhere, beneath the surface below, there is the food it must have.
     水下某个地方一定有食物
270. But where?
     可在哪里呢?
271. Those that fly above the ocean must be able to read the signs of fresh supplies, or perish.
     飞越海洋的鸟类必须懂得寻找食物的踪迹, 不然就意味着死亡
272. A hundred miles from the Mexican coast,
     距墨西哥海岸100英里,

来自《行星地球 第一季 第十一集 Planet Earth S01E11 海洋深处》第 269 行