At that point the killer whales separate the grey whales by manoeuvring between them or dragging the calves away by their tail flukes or fins.

此时，虎鲸会在灰鲸之间移动或抓住幼鲸的尾鳍将幼鲸拖走，从而将它们分开。

It also had a tail fluke to propel itself, as well as paddle-shaped limbs for steering and a little extra power.

它还有一个用来推动自身的尾翼，以及用于转向和一点额外动力的桨形四肢。

They're found on ribs, vertebra, tail flukes and flipper bones, and some of them are over 9 inches long and in some cases, 3 inches deep.

在鲸的肋骨、脊椎骨尾叶和鳍肢骨上都有发现这些沟痕，有些长近9英寸有些深度近3英寸。