by Carl Safina
Belly to the sideways breeze, catching the wind for levitation, she climbs. Then turning her back to that same breeze, she uses the wind differently—and adds gravity—to accelerate her forward and downward toward the surface of the ocean. She brushes the water and shifts her body again, transferring the downward momentum to help lift her, exploiting the force of gravity to take her upward. Having used the wind to take her up, she uses it to take her down; having used gravity to take her down, she uses it to take her up. This gives her a smoothly undulating, rocking flight; each wing alternately pointing skyward, then pointing toward the water’s surface, showing you now her dark back, now her bright belly. Wings fixed, she seems magically propelled.
Only as you watch her nearing the vanishing point—only then—do you begin seeing and feeling that these birds muster all their distance-eating achievement with their own effort and the skillful exploitation of their exquisite design. Keep watching as she shrinks to a pinpoint, swooping up and down, swiveling side to side, bounding onward into the boundless Pacific. Just this way, she starts steadily accumulating the great span of a great ocean, mile after mile after mile.
LETTING GO
AN HOUR AFTER AMELIA LEAVES, the last visual trace of French Frigate Shoals falls away behind her. She makes no note of it, as you make no note of leaving sight of your house when you run an errand. She sees herself neither as heroic nor hardworking. Nor does she have any other abstract concept. She has only purpose—to hunt—and she is keenly aware of that. And like any animal, like us when we travel, she knows where she is relative to home. But she has no visual markers on the ever-shifting ocean. Her mental map is not like yours. Her brain contains a compass—yours doesn’t—and a clock as accurate as your internal clock, which she pays more attention to. And of course, she has those wings. Albatrosses usually spend 80 to 90 percent of their time at sea flying, day and night.
The sea swells grow and roll beneath her, and fall away. Amelia’s flight follows them as she rises higher, her belly to the wind, the wind in her sails, then arcs into the downsweep of her flight path. Like this she goes for hours, this undulating flight, wings set and quivering against the breeze.
She’s averaging fifteen miles an hour, sometimes double or even triple that when the wind blows up. She seems in all ways calm and unflappable. Her broodiness is gone, and now this bird is sharply alert. She is traveling, traveling; and she is foraging.
The transmitter’s dialogue with the satellites will tell us where Amelia is. But we can also sketch a plausible picture of what she might be experiencing.
Though Amelia has no landmarks, she has her cues. Most birds have a poor sense of smell, but the tube-nosed birds carry olfactory equipment that’s among the most sensitive ever evolved. Amelia is sifting scent as she goes, so she sticks near the ocean surface like a seagoing bloodhound. And the sky is not empty of life. She isn’t all that far from home, and she shares the air. Terns and frigatebirds occasionally cross her line of vision. She reads them skillfully: terns going and coming in a low straight line, close to the water, have found a source of fish and are commuting. They’re worth following. Terns fifty feet above are searching, like her. They bear watching. A frigatebird flying high, tight circles may be watching a marlin or a school of Mahimahi, waiting out the inevitable sprint for flyingfish. If it’s late in the day, a pod of dolphins is worth following; a hunt may erupt, making fish available. Diving flocks of terns and boobies signal tuna; tuna signal eating-sized fish, plus a promising area to linger after dark in search of squid.
A line of weeds or flotsam is a good place to find floating objects with delectable flyingfish eggs adhered to them. These lines mark the friction at the borders of enormous masses of water that differ in temperature, nutrient concentration, productivity (thus color), and flow rate. Living things afloat, adrift, and aloft all strongly tend to collect at these energized boundaries, both because new nutrients get injected into sparser waters and because the friction slows the current edges, concentrating minute drifting organisms that ignite the whole food chain. Such places are a bit like bustling frontier towns of countries in the sea, save that their locations are ever-changing with the winds and moving waters. When the breeze is off such a frontal zone, the scent wafts to Amelia, sometimes telling of an unseen meal miles away.
What to us is trackless blue ocean is to her recognizable territory, a familiar mosaic riddled with scents and signs. As we know that in our town the supermarket will hold food, a train will come along the tracks, children will fill the school yard, and a bus will appear at the stop, she likewise knows the sea’s vast and changing neighborhoods, and what to expect. She knows when to keep going, and where patience will turn to profit.
She keeps going.
THE SUN DIES IN SOLITUDE, off to Amelia’s left. She flies steadily into the deep night. As best we understand, much of this time, alternating halves of her brain are sleeping. (Once, when a ship in Antarctic waters made an abrupt ninety-degree turn, a Wandering Albatross that had been following for many hours slammed into the vessel and fell to the deck. Apparently that bird had been totally asleep.) Near midnight, 110 miles northwest of her nest, Amelia swerves around, turns directly into the wind, then adjusts course and begins flying. east. She’d used the breeze blowing from the southeast to shoot her away from French Frigate Shoals, and now she puts it on her right and a little ahead—at the two o’clock angle—so she can both use the cross vector for efficient flying and search the oncoming breeze for scents from upwind. By the look of her straight track, she’s found nothing. She continues on.
In the morning Amelia is ninety-four miles north of Tern Island. No sight of land guides her. But in a place that looks no different from any of the surrounding sea, her nose tells her to slow. Amelia is getting whiffs of a faint, earthy smell, a little like the aroma of freshly broken succulent vegetation. If she’d ever smelled a cut cucumber, it would remind her of this smell.
Unseen 220 fathoms below, the slopes of an enormous undersea mountain slump to an ocean floor 2,600 fathoms—three miles—deep (a fathom being six feet, roughly the span of a man’s outstretched arms). Amelia doesn’t know that a mountain is forcing currents up its slopes toward the surface. She doesn’t know that when water streaming up from the dark abyss is struck by sunlight, its untapped nutrients can nourish the single-celled plants that need both sunlight and nutrients. Nor that these plant celts—phytoptankton—give off that faint, earthy-fresh smell. She doesn’t know that small animals called zooplankton eat those plant cells, or that zooplankters get eaten by small fish, and the little fish feed squid. She doesn’t know that. She doesn’t need to. She knows this: the smell means food.
Amelia passes into the scent upwind, and the air goes pure salty again. She turns and the aroma resumes. She weaves along its line of origin. And suddenly she receives a whiff of something different. Very faint. It’s the smell of fat. Not blubber, not the kind of feast a whale carcass would mean. This mild aroma is from sea foam—including the whipped fat of minute diatoms whose microscopic bodies have been broken by rough water. The foam has drifted into a very subtle line, a thin, diluted concentration zone, formed at the surface where the current is eddying around water being deflected up the slope.
A few widely scattered groups of terns and several albatrosses affirm that this place might be worth investigating. But their sparseness suggests, “You should have been here yesterday.” Amelia searches sunlit waters over the unseen slopes. She searches all day.
She comes up with precious little. Not much more than a few jellyfish this time. The smell that drew her in seems to have grown fainter during the day. Nothing in her experience suggests to her that this area is worth further searching. Her nose tells her that the water temperature’s been steady; the air temperature at the surface hasn’t changed a whiff. The calm, hot weather hasn’t brought enough wind to mix up the deeper water for full benefit; at the surface it’s still mostly the same water for miles around. This water is too
blue and clear—so clear because it’s so empty.
She knows that very far to the right of where the sun will set, the way we call north, is a reliable place for food. But that is a trek for a different frame of mind. Not now. Right now she wants a meal for her chick. She wants food here. Her chick is small; she will settle for small amounts. And something about the newness of her chick begins tugging at her. It may be as simple as an urge to stick close to Tern Island when the days are still this short, but she feels it as a desire not to continue traveling. The evening wind, slacking, does nothing to urge her on. On this trip, there will be no long trek to the right of the setting sun.
She travels ninety miles farther east, and goes dozy in the dark, until past midnight she catches another interesting whiff that rouses her to full wakefulness. She turns south. The scent vanishes in a slight wind shift but she continues in this direction, and after about an hour she briefly gets that weak scent again. She flies another hour. Now the scent strengthens. Amelia slows. She’s over a larger but much deeper bulge; this one rises to 1,700 fathoms, in water 2,700 fathoms deep. If there is a drift line, or surface rips in the running tides, or any other visual cues, they’re invisible in the dark; but the scent is familiar enough.
In the starlit black waters of a moonless night, she sees lanternfish flickering to each other, blinking the lights along their bodies like scouts with signaling mirrors. They’re generally too small for Amelia to catch, but she knows patience here now could mean squid—squid in the dark that have followed the lanternfish up a thousand feet since sunset. In the inky water, those puckering hunters become the hunted. Amelia sees a small pod of squid come and go from her field of view. She wheels and sees other squid rushing small lanternfish. Several squid succeed, and as they maneuver their wriggling victims toward their beaks they blush darker to conceal themselves and their meals from hungry schoolmates. Occupied in their own stealth and mutual mistrust, the squid fail to detect Amelia’s night-cloaked, gliding approach.
She plows in heavily, like an unseen truck speeding into a busy intersection. Suddenly among the squid an enemy is jabbing. Puffs of ink explode in the water like bombs in the D-day sky. Narrowly, all the squid scatter safely away.
All but one.
Amelia sits watching for more squid. “Patience, patience, patience, is what the sea teaches,” wrote Anne Morrow Lindbergh, “patience and faith.” A disturbed jellyfish lights up momentarily, and its glow catches Amelia’s attention out of the corner of her eye. Her glance reveals several more squid prowling just under the surface. She paddles toward them—half spreading her wings because she wants to hurry—and extends her neck just in time to reach one at the edge of the withdrawing group. When she is done swallowing, she shakes her head in the cool seawater, cleansing the squid’s thick, muddy ink from her fine white face.
At first light, the surface life of night—the lanternfish and their pursuers—drift downward like vampires afraid of daylight. They track the black depth toward another day of deep meditation.
For hours and hours—all day—she searches this thin broth of sustenance in the sparse tropical sea. She courses over the edges of unseen slopes deep below, following her nose and the subtle surface turbulence those slopes create in the streaming currents. A squid floats dead at the surface. Amelia lands and paddles forward, nailing it on her impaling bill.
The more food Amelia finds, the more she feels her chick pulling. She can feel that new chick like a rubber band, like a downy bungee cord. Nearly 156 miles into the ocean from Tern Island, she suddenly sets course directly for home, and the satellites log the route change. For ten hours she sails a straight track as if connected by a taut wire to her unseen nest and her fluffy baby.
The satellite has given us tracks on the map. Using everything else we know, we’ve filled the map with plausible details. Here at Tern, Amelia is again flesh and blood after two days at sea. It is February 12.
AMELIA AND HER MATE exchange brief greetings and a matter-of-fact farewell. Their chick, unveiled to sunshine, lifts its wobbly, hopeful head and opens its stubby bill to a narrow V. Amelia leans forward, centers her gullet on that V, and fills the chick with gooey food until satisfaction reigns and the world seems a secure and happy place. Meanwhile, Dad is off on his own overnight foraging foray. Amelia settles in to brood their fragile chick.
When Dad returns the next day, Amelia rises into the air again. She heads northwest as she did last time. But this time she tries a different area, one she’s visited many times.
Amelia is now following the crest of the undersea range whose widely separated peaks break the sea surface to form several of this chain’s islands. She overflies Rogatien Bank, whose unseen slopes rise from a depth of sixteen thousand feet to water as shallow as seventy feet. Here the tide flowing across the steep bottom contours creates swirling stretches of surface turbulence and a rough chop full of whitecaps. Amelia scans the glittering tide rips as she courses along with the greenish shallower water on her left and the deep blue sea on her right. She’s looking for anything shoved up by the dark currents. There isn’t much today. She finds one deceased lanternfish and sees a few small pumice stones in the drift lines. Pumice is volcanic rock that’s often so full of air bubbles it floats. It may be ancient, but today it will be lunch, because flyingfish eggs are stuck to it. She lands, and swallows the eggs and their hard pumice pit. She picks and pokes at a jellyfish here and a few more fish eggs there, at intervals separated by miles, until she has a meager payload. After working her way northwest in a nearly straight line for six hours, she slows.
Amelia is still on the crest of this one long underwater ridge. Fifty miles west of here and unseen, one peak of this mountain creates surf as Gardner Pinnacles. Almost eighty miles to the southeast, we know another peak as French Frigate Shoals.
The lingering memory that equates north with food begins to motivate her. No taste on the breeze hints of more food here, or a new body of water in the near distance, or of any other change—except a change for the worse in the weather. The weather ahead looks bad. She has sailed into plenty of awful weather. But that was when there was food. Nothing here indicates more food. A line of approaching thick clouds and a sudden headwind help her decide. Having flown seventy-seven miles in a straight line to the northwest, Amelia turns abruptly around and zips directly home for Valentine’s Day.
IT’S PROBABLY SAFE to infer that she hasn’t been satisfied with the results of her foragings, because on her next launch, only a day after arriving, she goes in the opposite direction, to a place virtually no albatrosses ever go.
Few of the hundreds of thousands of albatrosses from these islands head south, ever. But on this trip, for some reason, Amelia does, flying directly southeast, just under three hundred miles. Ocean-temperature monitoring buoys placed by the U.S. government are telling satellites this story: Amelia has passed into more tropical waters, the temperature rising more than three degrees Celsius, to 24 C (75° Fahrenheit). Here, near dawn, the marbled aroma of colliding currents and the scent of schools of fishes reaches her.
Fishing boats in the tropics read water temperatures assiduously. They travel hundreds of miles white looking for those temperature changes that indicate a water border and the animals it implies. They are guided by satellite-imaged sea-surface-temperature maps faxed or downloaded on board, as well as by onboard temperature instruments. Albatrosses and fishing-boat captains read clues using different methods, but they speak the same language.
Amelia wanders twenty-five miles to the west. She wheels and backtracks: back toward the marbled scents for twenty miles in the scaring tropical daylight. She sees fair numbers of flyingfish but catches nothing. If you want to catch flyingfish for a living you have to be either an expert plunge diver, like a Masked Booby, or a master aerialist, like a Red-footed Booby or frigatebird; and you have to hang around predatory fishes like tunas and marlins that will flush the flyingfish for you. That’s not in an albatross’s job description or
list of qualifications; it’s not the evolutionary ad they’ve answered. So they have to limit themselves to taking an occasional dead one. All those seabirds that attack live, agile prey in the daytime are downhill racers. Albatrosses are cross-country skiers, built for economical travel. Everyone ends up back at the lodge; they just take different routes.
Amelia works back northwest for another sixty miles, until the sun is slanted. There, her track turns back abruptly, following a straight line southeast for forty miles. Likely she’s found a fishing boat hunting Big-eye Tuna with a forty-mile longline, sending a thousand hooks into the depths. She is following. And a dangerous game begins: trying to snatch squid from the hooks before they sink. without being hooked and drowned.
She’s less effective at grabbing the sinking bait in the dark, so she peels away from the boat. She continues working this area, finding a group of spawning flyingfish vulnerably oblivious in their passion near the surface of the night. For failing to pay attention to how dangerous the world can be, two fish forfeit their lives.
When she feels that chick tugging and her time running short, she puts the trade wind into her wings and sets sail for Tern Island, still over three hundred miles away. Her twenty-hour track home is astonishingly direct. She appears at her nest on February 17. Since leaving two days ago, she’s flown a total of 917 miles.
AMELIA’S ARRIVAL and her feeding of the chick has prompted her mate to leave. Their chick is almost two weeks old. In average weather it no longer needs brooding. Barring extreme heat or prolonged chilling from soaking rains, it can now maintain its body temperature. It can also survive a little longer between feedings. Amelia has been losing weight since her chick hatched. So she plays the averages, gambling that the weather will be normal. On the very same day that she’s arrived, Amelia’s own hunger launches her on her next hunt. Her chick, for the first time, is home alone.