A Little Thing About a Whale
By Kirsten Shae Johnson
In whale space, below and beyond our usual encounters with the sea, it is not the water that speaks, but the land. Hundreds of meters below the surface, these earth symphonies flow along a channel of water, where temperature and pressure bend sound waves into the current and carry them thousands of miles. Wandering glaciers chime like bells, ice growls with friction, and pockets of lava, cooling in the brine, expire with a puzzled whistle.
Amidst this terrestrial song, the call of the blue whales is a humble one. They sing in the pitch of tectonic plates, in infrasound, a frequency so low it is more force than expression. They call in earth voices, the sounds of grumbling planets. It is then ironic that many of our whale stories involve men mistaking the creatures for land. Physiologus, a second century Greek, wrote of "a certain whale in the sea" that sailors would mistake for an island, until the heat from their campfires drove the whale to dive. Sinbad lost a number of men to just such a mistake.
Except for the weaning years, blue whales spend much of their time in solitude. In the Pacific Ocean, they follow currents that have been moving along the sea floor from the Atlantic, around the Antarctic, and up to the Pacific, in a journey that sometimes lasts a thousand years. In the summer months, these cold currents rise near Puerto Rico, feeding great clouds of plankton, which in turn feed great blue whales. But in the winter, the winds off North America move the upwellings closer to central California. And so the whales journey north.
This is the breeding time. Male blue whales, silent for most of their lives, erupt into song. Their calls can travel thousands of miles, crossing oceans, and consist of two parts. It starts as a popping grumble, which feels a bit like a propeller bumbling into motion, and ends in a low, longing moan. We think that they sing by moving air around in their heads, shifting it between nasal sacks, their skulls acting as resonance chambers. No matter what the size of the whale, they all sing at exactly the same pitch, varying their couplets by volume and rhythm, but not by frequency. As the voices rise and fall with each whale's song, females, listening to the Gregorian orchestrations, deliberate whose call to answer.
In the midst of this wooing, for the past twelve years a single blue whale has been calling at a pitch no other whale will even hear, much less answer. He calls out his couplets, but where the other whales sing 20 Hz earthquake songs, his call is closer to that of thunder, humming at 52 Hz. The other whales sing a C four octaves below middle C, while our whale sings a G sharp. To the rest of the ocean, his cries are just part of the background symphony -- perhaps a geyser somewhere, or an iceberg.
Nothing is known beyond his song: the scientists who have followed him for a decade aren't even certain that he's a blue whale, despite his couplets; he may be the hybrid offspring of a blue and another species. They don't know why his voice is pitched so high, whether he is misformed or simply miswired -- broadcasting on the wrong frequency but listening on the right one. They do know that b52 has traveled as many as 11,000 miles every year, moving east and west, meandering over short distances, and swimming north and south, calling out from central California to the Aleutians. His calls, and his path, cut across the heated pods of courting whales. He follows no common migration; the patterns of his movements have little in common with the careful ballet of the other blue whales. But each year he ventures a little farther south, widening his search.
Unlike the other whale cries, b52 is audible to human ears, though just barely. It's heard at that low threshold where, for most of us, hearing is almost hallucination. His call, too, starts with a rumble, a sonar-like grumbling and snapping, before it floats into a low breathy cry, like a breeze moving over hollow reeds, until it falls away, like a sigh.