http://www.bbc.co.uk/nature/animals/features/76grey.shtml
Black and white versus grey
As we approached, we saw flashes of black and white: killer whales. A few hundred metres ahead was a grey whale mother and her calf, and the gap was closing. Suddenly, the water violently erupted. Whale flukes and fins broke the surface. It was an attack.
The pod of about 15 killer whales worked together to tire the grey whales and separate the mother and calf. The attack was sustained and violent, the killer whales repeatedly ramming into the side of the calf with extraordinary force, no doubt inflicting serious internal injuries. At times, the calf's body was thrust partly out of the water. The calf was about six metres long, and so the force needed must have been tremendous.
It was incredible to watch such a concerted effort by the killer whales and impossible not to admire their co-operation and strength.
Seeing the desperate calf fight for its life was heart-breaking, and I wished that the killer whales would dispatch it quickly. But the most moving sight of all was the mother repeatedly trying to protect her calf by repositioning herself between the killer whales and her calf if they were separated, or more dramatically, by swimming underneath the calf to push it out of the way of the killer whales. Again, an incredible feat of strength.
As the calf began to roll in the water, we could see its bleeding pectoral fins, with distinct teeth marks where the killer whales had been holding the calf to prevent it surfacing and so drown it. The water around the calf began to turn red.
After hours of trying to protect her calf, the mother slowly swam shoreward, as though realising that her offspring was lost. We occasionally glimpsed the calf's beautifully dappled flank as a small group of killer whales dived and pushed it to the surface to eat. Then, the calf's body sank slowly beneath the surface for the final time.
