It's difficult for a single dolphin to catch the fish. 单只海豚想吃它们是很困难的

61. The dolphin scan the water ahead with their sonar.
    海豚利用声纳扫描大海
62. They're close to their target.
    已经接近目标
63. This is it. Scad mackerel.
    这就是了!竹荚鲭
64. It's difficult for a single dolphin to catch the fish.
    单只海豚想吃它们是很困难的
65. To avoid wasting energy the work as a group.
    为了避免浪费精力,它们进行团队合作
66. They drive the fish upwards, trapping them against the surface
    它们将鱼儿赶上海面,目的是诱捕它们
67. and there, other predators await them.
    因为那里还有掠食者在等着鱼儿们

来自《行星地球 第一季 第十一集 Planet Earth S01E11 海洋深处》第 64 行