英语听力：自然百科 大迁徙之繁衍生息 Need to Breed—13（在线收听）

 And the raptor executes his cool mercy.In the rolling surf, rockhoppers pop home with their garlics full. They take turns  shuttling to the sea daily  , having tibets of quilt to feed their growing chicks. Once ashore, the rockhoppers trade their long graceful sea migrations for a daunting and dangerous vertical one. They made their nests high on the sheer cliffs far from the freezing sea spray. And each day, podgy with baby food, they must scale these unforgiving rock moles.  Centuries of penguin passage have left their mark.