The fluke of the sperm whale:

Cold, cold, cold and a pure darkness defiled only by the occasional luminosity of a bizarre predator, softly drifting, gently nodding an alluring light that beckons to the unwary, draws the unknowing towards a bloated body, a ghostly beast with gaping jaws and a dagger-fringed grin.

SWISH! The unsightly fish is startled and tumbled by a passing shape, quick, fluid, and huge. Its lights are quenched, its body buffeted by a massive pressure wave, this former "terror of the deep" flees blindly into the blackness. The new arrival has no need of light to find his way, to pursue his prey. And this little "lightshow" is certainly not on the menu today, unless it foolishly gets in his way.

Yes, he knows it's there, as insignificant as it is. Click, click, click, click, click, a series of sounds, rapid beyond counting, pitched higher than hearing. These are sounds to build a picture, a three-dimensional hologram. He knows the shape of his prey as well as you know your face. He also knows where its hard, where its soft, whether its coming or whether its going, and how fast, all with sound, Click, click, click, click, click. They're ahead, a dozen, a hundred, a thousand, and more thousands.

CLICK, CLICK, CLICK. A huge sound, a hurting sound, a stunning sound, sound as a weapon. He drives through the school with jaw opened, his two-pound teeth exposed, each a battering ram crushing the stunned squid, cutting a swath through the school, like a bullet through a body. He can sense his pod-mates nearby doing likewise. They harvest a ton of squid in less than half-an-hour, these four, but they are huge and they are still hungry. But now it is time to return to the air, their oxygen spent, the carbon dioxide hurting. Up, up, up, a thousand feet. Light, heat, exhale and inhale within a heartbeat.

"They're up at ten o'clock," Lyall Watson, ship's naturalist, lecturer, and whale aficionado, breathes into the radio from his perch high in the crow's nest. "These are sperm whales!" says expedition leader, Tom Ritchie over the ship's P.A. "These are the largest of the toothed whales, which include the dolphins, porpoises and killer whales." he continues. "Notice the slanting blow, left and forward." Nine breaths, ten breaths, eleven breaths and time to go down again, into the cold again, into the dark. A final lifted fluke and we are left breathless and wonder, "What is it that they do down there?" And we wait; we wait until next time.