Five million birds make this journey every year. 每年有五百万只雪雁都是这样迁徙

67. But it's about to change.
    但这一切即将发生变化
68. Snow geese.
    雪雁
69. They winter along the Gulf of Mexico, and in spring they fly the entire length of North America to reach the Arctic tundra.
    它们在墨西哥湾越冬 等到春天便一路飞过北美洲 来到这里的北极苔原
70. Five million birds make this journey every year.
    每年有五百万只雪雁都是这样迁徙
71. Their marathon migration is almost 3,000 miles long
    这场马拉松式的迁徙长达三千英里
72. and has taken them three months.
    耗时多达三个多月
73. Exhausted and starving, they touch down inside the Arctic Circle,
    虽然早己精疲力竭 饥肠辘辘 但它们终于返回了北极圈

来自《行星地球 第一季 第七集 Planet Earth S01E07 伟大草原》第 70 行