Terror in Black and White

Natural History, Dec, 1998 by Robert L. Pitman, Susan J. Chivers

After witnessing some two dozen attacks, we begin to wonder aloud why the sperm whales don't defend themselves. Old whaling accounts are filled with graphic descriptions of sperm whales lashing out at whalers who attacked them, at times destroying longboats with their flailing tails or snapping jaws, or even ramming whaling vessels with their blunt heads. Sperm whales can also dive for over than killer whales can. And nothing in our years at sea working with whales has prepared us for such apparent helplessness.

We also have another question: why aren't the adult male killer whales participating? Only the adult females and their young have so far been involved in the raids. Adult males are substantially larger, outweighing females by as much as a ton and a half. But the only ones we have seen in the area have stayed out of the action. What are they waiting for?

Killer whales hunt in packs like wolves, and this group may have spent decades together honing the cooperative skills necessary to bring down large prey. This morning they seem intent on breaking up the rosette and isolating individuals. During one of their sorties, a sperm whale is pulled away from the rosette and immediately set upon by four or five attackers. We can see several black-and-white shapes beneath the water; the group is charging at the sperm whale from both sides. Twisting their bodies and violently shaking their heads like huge hungry sharks, the killer whales try to wrench off mouthfuls of what must be very tough flesh. The tempo of the attack picks up, as though the killer whales sense they are gaining the advantage. The sperm whale cannot survive this punishment for long.

Then, to our astonishment, two sperm whales leave the rosette formation and approach their isolated companion. One on each side, the two begin to herd the severely injured whale hack to the rosette. For a time, the killer whales redirect their attack to the escorts, then retreat once again. We see this same heroic scenario several times: one or two members of the rosette invite attack on themselves in an effort to bring one of their own back into the formation. All who watch are shaken by these acts of apparent altruism.

Eventually the sperm whales become disoriented. They try, but fail to hold the rosette formation. All appear to be wounded, several severely. The number of killer whales in the area is building--we now estimate there are forty to fifty--and the raiding parties are getting larger. Perhaps emboldened by their success, they attack with increasing intensity. Earlier, during the actual attacks, the killer whale calves were left swimming outside the rosette, but now they tug on whale flesh alongside their mothers. Could this be a training exercise? Or could the area now be safer because the sperm whales are weaker? The mothers are solicitous of their young calves, a behavior that starkly contrasts with the carnage of the hunt, and we are aware of our own tangled emotions as we watch in horror and fascination.