虎鲸捕食竟靠复杂的团队合作

The seal feels perfectly safe lying on the Antarctic ice even if it is surrounded by a pod of killer whales.
　　对于海豹来说，即使有一大群虎鲸在他周围，躺在南极的冰面上他也觉得异常完美。

But within minutes it has been knocked into the water in a clever team tactic before being killed.

但是几分钟之内，被杀之前，他就会按照一定次序进入水中。

These astonishing pictures show how the sea predators work together - and the technique provides meals for killer whales three out of every four times they use it, according to scientists.

这一系列让人吃惊的图片都展示了海洋捕食者是怎样合作的，而据科学家们书，虎鲸每顿饭都要用三四次这样的方法进行捕食。

Research has also found that the mammals - around 26ft in length and weighing more than six tonnes - carefully butcher the prey underwater, co-operating as they skin and dissect the seals.

研究还发现这种重达六吨的哺乳类动物，在水底捕食海豹的时候，也会互相合作。

Dr Robert Pitman, a marine scientist at the National Oceanic and Atmospheric Administration in California, took the stunning images of the pod going in for the kill.

在加利福尼亚州国家海洋和大气管理局的海洋科学家罗伯特·皮特曼博士，拍到了这群动物如何一起进行猎杀的图片。

He said: 'The killer whales were very good at knowing in advance if they were going to be able to wash a seal off a floe and they were always successful in getting the seal into the water.

他说，“虎鲸都知道将海豹赶下浮冰他们就成功了，而且他们也很擅长这么做，非常轻松的就能把海豹弄到水里去。”

'A couple of times the seal was washed off but managed to escape in the confusion, but not very often. From killer whale studies elsewhere we expected this kind of social interaction but it was the canniness of their hunting tactics that blew us away.'

“有几次海豹会试图逃跑，但是这种情况并不会经常发生。虎鲸让我们意识到了这种社会关系的重要性，但是他们捕食猎物时的机警和迅速还是让我们所有人都感到吃惊。”

Dr Pitman and his colleague Dr John Durban helped a BBC film crew capture their behaviour for the TV documentary series Frozen Planet, to be shown later this month.

皮特曼博士和他的同事，约翰·德班博士，帮助BBC拍摄的虎鲸捕食猎物的纪录片，冷冻星球，将在这个月的晚些时候上映。

They spent weeks tracking and recording the hunting behaviour in the pack ice off the coast of the Antarctica Peninsula.

他们花了几个星期的时间在南极洲的半岛的冰盖上跟踪和记录虎鲸的狩猎的行为。

The whales prefer weddell seals, which can be up to 11 feet long,rather than the more aggressive crabeater and leopard seals.

鲸鱼们似乎都喜欢吃韦德尔海豹，他们能有11英尺长，比一般的黑鳕鱼和海豹都更难捕获。

Dr Pitman told the Sunday Telegraph that the whales deal with seals who try to hide among the ice after being knocked into the sea by creating shock waves with their tails to knock them out into the open water.

皮特曼博士告诉周六邮报说，鲸鱼处理那些试图隐藏在被撞击的冰块后的海豹，他们会用他们的尾巴制造波浪，并将海豹们赶到开放海域中去。

He said: 'The whales also blew streams of bubbles under the seals apparently trying to get them to bolt into open water where they wouldn't have a chance against the waiting killer whales.'

博士还说，“鲸鱼也在海豹旁制造很多泡泡来吸引他们进入开放的海域，否则当虎鲸出现的时候，他们就没有任何机会了。”