Voices in the Ocean

by Susan Casey

  Two colleagues of Baird’s, Dan McSweeney and Deron Verbeck, had spent time in the water with false killers, both men returning with extraordinary stories of how engaged the animals were. One time, McSweeney was diving near a pod when one of the pseudorcas swam up to him with a tuna in its mouth and spat it out at him, as though delivering a gift. He took it; the whale swam away and then boomeranged back. McSweeney handed the fish to the whale, who once again took it gently in his mouth. “It’s not the first time this kind of thing has been documented,” Baird pointed out. “It’s basically ritualistic prey sharing. I say ritualistic because I think it has a symbolic component to it.”

  While other top predators such as sharks and lions often shared the spoils of the hunt, jointly ripping into whatever they’d caught, Baird had observed false killer whales simply passing a fish around among themselves, without anyone taking the slightest nibble. “I don’t know of any other species that does this,” Baird said. “So, why would they? Well, they’re hunting companions. They’ve probably been hunting together for years. They’re buddies. It’s a way of demonstrating trust. And the fact that they give it back…it’s not like they’re trying to get more of the fish themselves. The purpose of this isn’t just to eat the prey. There’s something more: it’s part of their culture. And you know, what’s going on in the head of an animal that actually brings food to another species?” He smiled. “I have a dog. He’s really cute. But when I give him a bone, he’s certainly not going to offer it to me.”

  By now we had cruised thirty-five miles to the southern tip of the leeward coast, and Baird began to turn the boat around. We’d been trolling through water four thousand meters deep, and now we would make our way back at a slightly shallower depth. So far, no dolphins. I could see where the lava from Mauna Loa had rivered to the sea, with an isolated fishing village, Miloli’i, perched at the shoreline. Baird had just opened a package of Ritz crackers when his phone rang. “We’re in the southern part of Kona,” I heard him say. And then I watched his face turn to stone.

  The call was brief. Baird hung up and turned to Webster and me. “As we speak, the Navy is using mid-frequency sonar,” he said, in a tight voice. The caller, Baird told us, was a dive captain who’d heard the sonar reverberating through the hull of his boat: “Divers are getting out of the water because it’s too loud and painful.” Worse, this was all happening near Puako, a patch of ocean Baird had repeatedly urged be categorized as an exclusion zone. It was home to a resident pod of 450 melon-headed whales, a tribe that did not tolerate war games well. After sonar lit up the depths during the 2004 RIMPAC, two hundred melon-headed whales stranded in Kauai’s Hanalei Bay.

  Baird, agitated, began to make more calls. He was visibly upset. “In my opinion, it’s really irresponsible of the Navy,” he fumed. “It’s a PR mistake, big time. They could go somewhere else—and they go where there’s a sensitive species and people have to get out of the water?” Baird stared at the ships in the distance. His face was flushed, and not just from the heat. “How can that be good for anyone?”

  The discovery that certain animals navigate their worlds by relying on sound rather than vision dates back to 1773, when an Italian scientist named Lazzaro Spallanzani noticed that bats could fly expertly in total darkness, swerving around obstacles they couldn’t possibly see. Astonished by this, and somewhat spooked as well, Spallanzani caught some bats and began to experiment with them.

  You would not have wanted to be one of Spallanzani’s bats. Though his first experiment was sort of cute—he outfitted the creatures in tiny hoods—Spallanzani quickly moved on to heavier-handed efforts, blinding them and even removing their eyes, coating their wings in varnish and flour paste. But once the bats recovered from their injuries, they could still hunt with ease, even eyeless. Spallanzani was stumped. He moved on to their ears, plugging their auditory canals with hot wax. This time, success: the bats bumped into things. Without their hearing, it seemed, they were lost. When Spallanzani presented his findings, surmising that bats were sonic savants without much use for their other senses, he was laughed at by some of the most renowned scientists of his day. His theory was shelved for a century, referred to dismissively as “Spallanzani’s Bat Problem.”

  But Spallanzani was right. Though it wasn’t until 1938 that his “problem” was solved by scientists at Harvard, even then the phenomenon of animals that could echolocate, or produce their own biological sonar, was poorly understood. In 1947, Arthur McBride, the curator of Marine Studios, pointed out that whatever this extrasensory skill was, dolphins appeared to have it too. The details of how this all worked was still anybody’s guess. It was only in the sixties—when Ken Norris presented the results of experiments in which he’d blindfolded dolphins with rubber suction cups and watched them move effortlessly through an underwater maze to locate a scrap of fish—that dolphin sonar was proven to exist. By this point, of course, dolphins had been echolocating for about 35 million years.

  Basically, active sonar involves sending out a beam of sound and then analyzing the returning echoes to determine the three-dimensional physical properties of an object in space, or underwater. Different materials reflect sound at different wavelengths; some items are bouncier and sonically brighter than others. Others absorb sound, sending back weaker echoes. All sonar systems, regardless of finesse, consist of three parts: a transmitter, a receiver, and a way to process the signals.

  Scientists soon learned that dolphin sonar was anything but basic. As one researcher put it: “To say that dolphins echolocate is like saying Michelangelo painted church ceilings.” The animals generate ultrasonic clicks using structures in their nasal passages (near the blowhole); a fat-filled sac in their foreheads called a melon focuses the sound. When the clicks hit an object the dolphins receive the echoes through their lower jaws, which are also lined with fatty liquids. From the jaws, the acoustic feedback is transmitted up to their ears and into their brain, where it’s interpreted and relayed to other senses, such as vision. Their clicks emanate in a stream, up to two thousand clicks per second, but dolphins can both aim and adjust each click individually, changing direction, volume, and frequency—a feat of unimaginable precision. They can even send out two click streams at once, in different directions, at varying frequencies. Using this sense, dolphins can detect minute variations in the size or composition of identical-looking objects, even at a distance. It’s a spectacular system, ideal for life underwater, where light is scarce but sound travels easily, 4.3 times faster than it does in air. When manmade noises flood the dolphins’ environment, it’s like us being blinded by light so bright that we can’t make out anything. But sounds are pressure waves—battering walls of energy—so for a more appropriate analogy, add to that our retinas painfully exploding in the glare.

  Through the decades, countless experiments have been done to tease apart the inner workings of dolphin echolocation, particularly by the U.S. and Russian navies. There are obvious military advantages to getting an edge in sonar technology: since the fifties the Navy has conscripted dolphins and made strenuous efforts to harness their underwater superpowers. Even if we couldn’t replicate their advanced sonar, we could certainly put it to use.

  To date, bottlenose dolphins have served the United States in Vietnam, Iraq, Iran, Bahrain, Norway, Eastern Europe, and by guarding the Trident nuclear missile base in Bangor, Washington, to cite some known deployments. America has approximately seventy-five bottlenose troops; in the past this number has been higher. Their main tasks—according to the Navy, which declassified its marine mammal program in 1992 but is still less than chatty about it—have been to provide surveillance around ships, and to identify underwater mines so they could be cleared. Beluga whales and sea lions, deep divers accustomed to cold water, have also retrieved lost missiles from the seafloor. (At one point orcas were also trained for war, but their tendency to disobey orders made them less reliable soldiers.)

  Officially, the Navy has always maintained that the dolphin
s, who are referred to as “Marine Mammal Systems,” were there for nonlethal purposes, including swimming around with cameras clamped to their heads. But there were rumors of more sinister missions, recounted by disaffected trainers. In 1973, Michael Greenwood, a dolphin expert who claimed to have worked with the CIA in Key West, alleged to Morley Safer on 60 Minutes that the animals had also been prepared for “swimmer nullification” work, shooting enemy divers with explosive darts and .45 caliber bullets. “The dolphins are being trained so that they can do any variety of exotic tasks,” Greenwood said, adding that many finned operatives had gone AWOL: “We have lost many animals. They run away very frequently.” “The military’s interest in dolphins is no Disneyland scenario,” Safer concluded somberly.

  Regardless of what assignments the dolphin troops have been given, now or in the past or in the future, the Navy has maintained that its dolphins “will be provided the highest quality of humane care and treatment.” On its Web site, in fact, it stresses that Congress has mandated this by law. No one should worry about these soldiers, the Navy says: “Marine mammals are actually in more danger from sharks, and…put in much more danger by people who feed them (which is why it is illegal).” Our Navy dolphins have taught us a lot, the Web site asserts earnestly, and “the more we know about marine mammals, the better we can protect them.” All of which is very reassuring, if you are inclined to believe an institution that is busily blasting the animals out of existence, using the same sonar technologies that we recruited them to help us develop.

  The sky the next morning dawned pink and windless, and Baird motored out of the marina with purpose. We were going north to Puako, and we were going there with cameras and hydrophones ready. Even from afar, RIMPAC was easy to spot: a parking lot of gargantuan vessels. Before long we ran into a pod of bottlenose dolphins. Baird eased off so we could take photos; Webster dropped the hydrophone. It bobbed in the water, a fluorescent flag signaling its location. Knowing that sonar had been used nearby, Baird wanted to find out if its pings were still audible.

  The bottlenoses swam up to the boat, game for a little wake riding: their bodies looked green below the water. I had been stationed on the bow, so I could see them closely. Many of the dolphins were marked with scrapes and cookie-cutter shark bites, round flesh wounds gouged out and healed over. One dolphin’s dorsal fin had been sliced in half.

  Standing on the bridge, Baird picked up his binoculars and scanned the horizon. “There’s a Navy vessel at one o’clock,” he said. “Second Navy vessel at two o’clock. That’s either a cruiser or a destroyer. They would both have tactical sonar 53C,” he explained, “but if they were using it right now, we would hear it through the hull. So I don’t think they have it on.” Another lummox of a ship was hunkered in front of Kohala’s Four Seasons hotel: “That one looks like the back deck lowers into the water so they can run amphibious vehicles into it,” Baird observed. As if to confirm his guess, a black hydrofoil emerged from the ship’s belly and shot across the sea, sending up rooster tails of spray. Three oversize helicopters had also appeared, sweeping in loud and low, beating the ocean into a froth. If you were a military buff this parade might be exciting, I thought, but it wasn’t the kind of scenery most vacationers longed to see from their $800-a-night ocean-front bungalows. As Baird had pointed out, it was a head-scratcher of a choice for a mock combat location.

  We waited ten minutes longer, then Baird steered us back to the hydrophone so Webster could retrieve it. As we approached, we could see something floating beside it. “What?” Rone said. “It’s an eel!” And it was: a snowflake moray, a reef-dweller that hides itself in crevices. Usually, the last thing an eel wants to do is leave its protective housing, but this one was snaking vulnerably across the surface, wrapping its gold and brown–striped body around the hydrophone as though desperate to escape the water. “What the hell is it doing up here?” Baird said. “This is bizarre.”

  When loud sounds boom through the ocean, all animals suffer, not just noise-sensitive cetaceans. Underwater detonations have a hellish history: in the past, the U.S. and Russia have even conducted nuclear tests in the ocean, generating aquatic mushroom clouds that exploded thousands of feet into the air, lighting the skies afire, boiling the sea, shooting out shockwaves and tsunamis that engulfed ships and even entire islands, miles away. You can read endless accounts of these whiz-bang experiments and never encounter a single reference to their toll on the living creatures below the surface, so their devastation can only be imagined.

  Not all damaging underwater noises are percussive or ear-shattering: some, like commercial ship propellers, drilling, dredging, and cable-laying, are a constant, droning backdrop, low frequency vibrations that reverberate for miles. (Imagine living round-the-clock with a chugging air compressor strapped to your head.) Scientists refer to this ever-present racket as “acoustic smog,” and they estimate that its levels have risen tenfold over the past twenty-five years. Industrial noise clangs and roars and hums through the oceans, obscuring the natural sounds animals use for mating, hunting, avoiding predators, navigating, migrating, communicating—really, for everything in their lives. As they try to escape the din or struggle to cope with it, they become chronically stressed and susceptible to illness.

  Supertankers rumble by at about 180 decibels below the surface. At 185 decibels, human eardrums will burst; 200-decibel shock waves will blow a cow off its feet and cause death on land. But the loudest undersea noise of all, even beyond an atomic bomb detonating (Hiroshima was measured at 248 decibels), comes from the air guns used by oil and gas companies to prospect the seafloor. To conduct these surveys, dozens of cannons are towed behind ships, discharging 250-decibel blasts roughly every ten seconds for months at a time, affecting marine life over vast areas of ocean. These explosions can deafen creatures, cause organ failure, and harm larvae; they can silence whales at enormous distances and keep them from feeding, and cause nearby cetaceans to strand. At any given time, scores of these oil surveys are under way in every ocean of the world, and their numbers are rising.

  As we wondered at the freaked-out eel and snapped pictures of it, the radio came alive, squawking with static. “Securité, securité. This is Warship 47. Conducting speed limiting engineering casualty control drills. Request all vessels maintain safe distance.”

  Heeding their warning, Baird turned the boat and drove farther out to sea. Before long, we found another expired squid, this one speckled with white. As Webster bagged it, Baird watched the ships through binoculars. The sunlight glanced hard off the water, frying us. “Do you want some of my sunblock?” Ward asked me. “It’s like superglue.” I took some and coated my ears and face, again.

  Webster, whose eagle-eyed vision rivaled Baird’s, suddenly pointed in front of us. “Kogia!” he said. This meant nothing to me, but everyone else snapped to attention. A black back broke the surface, followed by a blunt head. Whatever it was, there were two or three of them. They disappeared quickly, but Baird had seen enough to confirm the sighting: dwarf sperm whales. “This is one of the species that’s sensitive to Navy sonar,” he said with a frown. “There was a stranding on Kauai during the submarine commanders course.” We waited for almost an hour, but the whales didn’t show themselves again. “It’s an extremely poorly known species,” Baird explained. “We’ve got 115 individuals in our catalog and it’s the only long-term study in existence.” The animals, he noted, were tough to track, skilled at shaking observers off their tails: “There’s no relationship between the way they’re traveling when they dive and where they come up. Often they’ll go in a completely different direction.”

  Before I left, we would find more galumphing pilot whales, a raucous bunch of rough-toothed dolphins, and, most thrillingly, a pod of three hundred melon-headed whales. Baird had gotten a tip from a sportfishing captain and we found the melon-heads twelve miles off shore. Once we arrived, they were impossible to miss. They were the most convivial dolphins I’d ever seen, inquisitive and eager to p
lay with the boat, spy-hopping, streaking past us, and then logging at the surface in bunches. “They love to surf,” Baird said. “When you accelerate even a little bit, you’ll get twenty of them riding the bow.”

  Melon-heads live in expansive groups, and they appeared delighted with one another’s company. They were everywhere, and Webster managed to tag two of them and collect biopsies. Later, Baird would inspect the results and share them with other scientists, including geneticists and toxicologists. This was not the resident pod he was worried about: these were transients, moving throughout the island chain. A band of rough-toothed dolphins had joined them, and weaving among all the dorsal fins were two sharks, an oceanic white-tip and a silky shark, their slinky bodies visible at the surface. The rough-toothed dolphins liked to jump, pogoing high in the air, and they had calico patches of pink on their skin, and long, narrow beaks. If the bottlenoses brought to mind powerful BMWs, the rough-tootheds were Porsches with front-end spoilers. The melon-heads were more like souped-up Mini Coopers.

  The pods stayed with the boat for hours, everyone gunning their cameras, and Baird calling out directions from the bridge to help Webster aim his tagging gun, which resembled a miniature crossbow, as hundreds of dolphins darted around us and under us. (The last thing anyone wanted to see was a $5,000 satellite tag missing its mark and sinking into oblivion.) “Big male approaching you at two o’clock—target species,” Baird shouted, and then chuckled. “We affectionately refer to certain individuals as ‘targets.’ Later, we hope to refer to them as ‘tagged.’ ”