but desperate times require desperate measures. 但到了走投无路之时也会铤而走险

238. But lions have much more sensitive eyes.
     而狮子有着更加锐利的视力
239. The cats are hungry and the elephants seem to sense it.
     狮子十分饥饿 大象好像也感觉到了危机
240. Lions don't usually hunt elephants,
     狮子通常不会把大象当作捕杀对象
241. but desperate times require desperate measures.
     但到了走投无路之时也会铤而走险
242. This herd contains calves, easier targets.
     这一象群里有更容易下手的幼象
243. But how to reach them?
     但是怎样才能接近呢？
244. The adults encircle their young.
     成年象已经围成圈在保护小象

来自《行星地球 第一季 第七集 Planet Earth S01E07 伟大草原》第 241 行