And a century ago, the bison were reduced to barely 1,000. 一百年前 野牛的数量曾锐减至不到一千
Now, thanks to rigorous protection, the species is recovering. 如今 幸亏制定了严厉的保护 这一物种的数量才得以逐步恢复
but no animal is immune to intensive hunting by man 然而没有哪种动物能够幸免于人类的大捕杀
until the summer ends and they're forced to head south for the winter. 直到夏天结束 它们才会被迫南迁过冬
Their parents lead them down to the safety of the water as soon as they're strong enough to make the journey. 它们强壮得可以旅行时, 父母马上就带着它们来到更为安全的水域
For the foxes, boom time has come to an end. 对于狐狸来说 美好时光已经接近尾声
She has seven hungry cubs to feed. 这只母狐狸有七只饥饿的小狐狸要喂养
the mother must work tirelessly to raise her family. 母狐狸必须拼命觅食才能养活全家