Sounds Wild and Broken, page 33
Underwater seismic pounding feeds every one of us who use oil and gas. Yet we have no shred of sensory experience of the consequences of our hunger for these fossils. Stand on an ocean shore, and you will not hear the sound of seismic surveys. Take a ship into deep water and, even there, water’s reflective boundary and our air-adapted ears shield us. Analogy fails too. A pile driver in your house, running without stop for months? That gives an approximation of the loudness and relentlessness, but we can walk away from the house, and even when we stand next to the machine, the assault mostly affects only our ears. For aquatic creatures, sound is sight, touch, proprioception, and hearing. They cannot leave the water. Few can swim the hundreds of kilometers necessary to escape. The pile driver is coupled, minute by minute, to every nerve ending and cell, suffusing them for months on end with the violence of explosions.
Ocean life, especially near to shore or along busy trade routes, now lives in a din previously unknown except near underwater volcanoes or during an earthquake. Wind-stirred waves, breaking ice, earthquakes, the motion of bubbles in water columns, and the sounds of whales and snapping shrimp are the sounds to which marine life is adapted. But the blast of air guns, the needling and stab of sonar, and the throb of engines are new and, in most places, far louder than just a few decades ago.
The worst places in the ocean are now intolerable for much ocean life. Whales flee areas in which seismic testing is underway. A study off the southwest coast of Ireland found nearly a 90 percent decrease in sightings of baleen whales and a halving of sightings of toothed whales during active seismic surveys compared with “control” surveys with no blasting. Air guns also decimate the base of the ocean food web, the plankton and larvae of marine invertebrate animals. In an experiment off the coast of Tasmania, a single air gun killed every krill larva—a key prey animal in the food web of southern oceans—within more than a kilometer and wiped out most other plankton. The sound waves from the blast may have shaken the animals to death and, for the survivors of the initial shock, so ripped up the sensory hairs that cover the animals’ bodies that the plankton soon died, stripped of any ability to hear or feel their world. The sensory systems of larger invertebrate animals like lobsters can also be permanently destroyed by exposure to seismic surveys. Yet trade groups for the oil exploration industry continue to lobby for relaxed regulation of seismic testing, claiming that there is “no known detrimental impact to marine life” of large-scale surveys. They also claim that because the blasts go off every ten seconds and each impulse lasts one-tenth of a second, “sound is only produced for one percent of the entire survey period.” By this logic, a boxing match is not a violent affair and a beeping smoke alarm is mostly silent.
Naval sonar—the high-amplitude blasts of sound used to “see” below water through reflected echoes—can cause whales to dive and surface so fast that their veins bloat with nitrogen bubbles, connective tissues disintegrate, and organs hemorrhage. Sound bleeds them to death from within. Under assault from sonar, some whales come into the surf, try to hide behind rocks, or beach themselves in a bid to escape the torturous whine. These strandings and frenzied bids to escape the water bring the whales into the human visual realm, a rare sign accessible to the human senses of the crisis below the waves.
Even when sound is not immediately lethal, it exacts a toll. A recent review of more than 150 scientific studies of whales, dolphins, seals, and other marine mammals found that noise reduces feeding, cuts off echolocation, increases time spent traveling, decreases rest, changes the rhythms of diving, and drains energy reserves. Some species respond to ship noise by increasing the loudness and rate of their calls, others go silent.
Whales are social animals, living in continuous acoustic contact with their families and cultural groups. Whaling greatly reduced the complexity and abundance of these societies. Noise further degrades and severs social bonds. In highly social terrestrial animals, we know that reducing or eliminating connection to others injures, and in extreme cases kills, individuals. Less is known about the physiology and psychology of whales than about land-dwelling animals, but it is likely that noise increases distress and, in the long term, narrows the sonic pathways through which whale cultures thrive and evolve.
Noise also changes both the behavior and physiology of fish. In a noisy environment, they often become agitated, darting about as if a predator were close. But when a real predator shows up, they seem unable to defend themselves, not startling and speeding away as they should. For fish that use sounds during their breeding displays, noise has variable effects. Some species ramp up their calling, perhaps to shout over the background, but others go quiet. For many, noise either blocks or greatly reduces the range over which they can be heard. Some fish obsessively clean their nests and tend to their fry when noise rises, an increase in effort that, like their increased swimming, costs them both energy and time. When feeding, fish exposed to noise catch fewer prey, are less efficient, and find it harder to discriminate between good and bad food. Fish in noisy places have higher levels of stress hormones, and the development of their hearing suffers. In some species, mortality rates double from the combined effects of these changes.
The negative effects of noise even penetrate the ocean sediments. A study of burrowing clams, shrimp, and brittle stars showed that they change their behaviors in noisy conditions, reducing their movement and feeding. These changes to seemingly obscure creatures in ocean mud have consequences that ramify throughout the ecosystem. The burrowing and mud-filtering activities of these animals partly control the movement of nutrients in the ecosystem, including how fast these chemicals are recycled into the web of life or buried in deep layers. If this study represents a general finding, the noisiness of our oceans may leave its impression even in the stone that is left behind from our era, discernible to future geologists as a changed chemical signature in mud and rock, alongside the plastics, pollutants, and acidity that we have cast into the waves.
Off the west coast of San Juan Island, our whale-watching boat leaves the flotilla, the allotted time for our jaunt completed. The whales had swum north and circled back toward the island, their retinue following at a distance. We saw no more close approaches, but we gazed on their harlequin backs and flukes as the whales dallied at the surface.
Returned to shore, I feel wobbly on the unmoving asphalt. In a few hours, my muscles and inner ears came to know and expect the motions of water. When I feel steady enough, I get in the car and turn on the ignition. Gasoline squirts into pistons. It was likely barged here through the Puget Sound. Tree latex and fossil oil in my tires whirl over the road, flaking rubbery dust onto the impervious surface, a silt destined to wash to the sea. Back at a hotel, I plug my laptop, imported from across the Pacific via ship, into the wall socket. The screen’s glow and microchips’ warmth are fed by turbines in dams across formerly salmon-filled rivers, supplemented by the splitting of uranium atoms and the combustion of coal and gas. I lie down on a mattress permeated with flame retardant.
Headphones on. Click: Orcasound.net. Click: listen live. As the sky fades from dusky gray to security-light pearl, I drift with the sounds of water ticking and sloshing against a hydrophone thirty meters off the west coast of San Juan Island. Gentle knocking sounds. A crab moving around the kelp? A high whine, like an electric motor, runs for two minutes, then cuts off. A few outboard engines pass, atonal whirs. Through the night, the sound threads in and out of my sleep, waking me into confusion before dawn with the burr and slash of propellers gunning a boat through the water.
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The noise in the ocean today is infernal, but not hopeless. The acoustic devilry that we daily stream into the subsurface world can be stopped. Unlike chemical pollution that lingers sometimes for centuries, or plastics that will persist for millennia, or the death of the coral reefs that will not be reversed for millions of years, sound pollution can be shut off in an instant.
Silence from humans is unlikely, though. Whether or not we are aware of our dependence on the sea, we are a maritime species. The energy and materials that supply our bodies and economies move largely by ship. Most of our oil, gas, and food travels among continents by sea. There is little chance, therefore, that the noise will cease entirely. But quieter oceans are within reach.
It is possible to build almost silent ships. Navies have been doing so for decades. Some submarines are so stealthy that their presence can only be revealed by pumping into the water sonar loud enough to deafen any passing dolphin. Fisheries researchers seeking to measure fish abundance and behaviors do so from vessels with engines, gears, and propellers engineered to reduce noise and thus not alarm fish. The hush from these ships comes at the cost of efficiency and speed. Yet even for large commercial vessels, noise can be greatly reduced through careful design. Regular propeller repair and polishing reduce the formation of cavitation bubbles that are the main source of noise. Further reductions come from changing how engines are mounted, adjusting the shape of propeller blades, modifying propeller caps, sculpting the flow of wakes, adjusting how propellers interact with rudders, and operating propellers so that they spin at rates that reduce cavitation. Slowing the vessel, even by 10 or 20 percent, also cuts noise, sometimes by up to half. Many of these changes save fuel, giving a direct benefit to the ship operators, although not always enough to offset the costs of expensive reengineering. More than half of the noise in the oceans comes from a minority—between one-tenth and one-sixth—of the vessels, often older and less efficient craft. Quieting this clamorous minority could significantly reduce noise.
But without a reduction in the volume of traffic, quieter ships might lead to more ship strikes if whales cannot hear approaching danger. For millions of years whales have safely traveled and rested at the water surface. Now blows from hulls and slashes from propellers are significant risks for whales in ocean shipping lanes and around busy ports. Technological tweaks have unintended consequences, especially if the movement of goods around the world continues to grow.
The most harmful effects of sonar can also be reduced, at least for large marine mammals, by locating navy exercises away from known feeding and calving grounds, tracking whales and shutting down war games when they are close, gradually ramping up sound levels so that animals have time to escape, and reducing long-term exposure by not repeatedly subjecting the same animals to high-amplitude sonar. As with shipping noise, reducing the overall number of ships conducting exercises would have the most significant effect.
Even seismic surveys can be hushed. Were we to wean ourselves from the black milk of Earth, we would have little need to rake the oceans with sonic death rays. Failing that, other methods now exist to map the subsurface. Machines that send low-frequency vibrations down into the water column yield excellent maps of buried geology while making less noise than air guns. This “vibroseis” technology is regularly used on land but has yet to be widely adopted in the ocean. Marine vibroseis produces sounds that overlap with animal senses and communicative signals but does so over smaller areas and in a narrower frequency range.
These changes are mostly now only experimental, hypothetical, or enacted in small corners of the oceans. Regulation of marine noise happens piecemeal by country, with no binding international standards or goals. The noise in the oceans continues to worsen. The United States Navy’s 2020 plans for sonar in the waters around Washington State were so aggressive that the governor and five leaders of state agencies wrote to the National Marine Fisheries Service demanding changes, including the use of preexisting real-time whale alerts systems and expanded buffers around high-energy sonar buoys. A 2016 estimate of global shipping noise projected a near doubling by 2030. A review in 2013 found that expenditures on seismic surveys were increasing at nearly 20 percent per year, more than ten billion dollars annually, capping two decades of rapid growth. Decreasing oil prices and the COVID-19 pandemic have now slowed this rise, but demand for more surveys will likely surge if prices rise. The US military plans to soon start broadcasting continuous noise into all ocean basins to guide underwater vehicles.
The ever-increasing noise in the ocean is directly tied to the extinction and diminishment of life’s diversity elsewhere, especially in tropical forests. In Borneo, forest-based local communities are being extinguished in favor of logging, mining, and tree plantations. These commodities all serve the global economy and are transported by ship. The worldwide decline of local economies, caused by ever-growing volumes of international trade, results in deforestation, loss of land rights to local communities, and ocean pollution of all kinds, including noise. The impoverishment of sonic diversity on land and water, then, is part of the same crisis. Were we to re-create vibrant local economies, we’d have less need to transport materials and energy across oceans. We would also directly sense the human and ecological costs of our actions, a stronger foundation for wise ethical discernment. Such a reformation of the economy would not resolve the many problems we create, but it would better position us to find solutions and answers.
We possess the technology and economic mechanisms needed to reduce our noise. But we lack sensory and imaginative connection to the problem and thus the will to act in solidarity with “our relatives under the waves.”
My turntable spins. The humpback whales’ songs are alive again in my headphones. I try to imagine where these animals are now. Watlington and the Paynes recorded them in the 1950s and 1960s, and so the whales were likely born sometime in the first decades of the twentieth century. These animals lived through and within the peak of our slaughter of their species. More than two hundred thousand humpbacks were killed between 1900 and 1959. Nearly forty thousand were killed in the 1960s. The singers I hear from the album on my turntable may, if they were the unlucky ones in the 1960s, have been killed and turned into soap, transmission fluid, textile mill lubricant, rust-resistant paint, and, after their oils were hydrogenated, margarine. Certainly, many of their kin met these fates.
If they survived, the singers on the album may still be with us. These animals would recall the sonic magnificence of the oceans before the mid-twentieth century. For bowhead whales that can live for centuries, the sonic revolution in their world is more drastic. In their younger years, some of these animals knew the oceans before engines, air guns, or sonar penetrated the waters. In those days, and for millions of years before, whales filled the oceans with sounds. Whales were up to one hundred times more abundant then than now, a total population of millions of individuals. Today a single whale can sometimes be heard from across an entire ocean basin. Imagine millions of these animals giving voice. Every water molecule in the oceans continually thrummed with the sound of whales. Vociferous fish, now decimated, formerly sang by the billions on their breeding grounds and added their sounds to the whales’ calls. The ocean world pulsed, shimmered, and seethed with song. Unlike air guns, sonar, and shipping noise, these sounds did not kill, deafen, and fragment the community of life. Instead, as sound does in all living communities, they connected animals into fruitful and creative networks. Given a chance, this could return.
The work of Roger Payne and other apostles of whale song in the mid-twentieth century drew our imaginations into the oceans. What we heard compelled us to act. Now the seas are riven with new crises, yet our cultural imagination is mostly disengaged from the sonic tumult we create. Networks of hydrophones along coasts, feeding sound into homes, classrooms, and museums, are now healing this disconnection. Journalists, such as Lynda Mapes and her colleagues at The Seattle Times, are creating stunning multimedia evocations of coastal whales and their environments. These are inspiring catalysts. But most who profit from the sonic destruction of the oceans—almost all of us in industrial societies, from consumers and shareholders, to regulators and corporate heads—seldom feel the appalling nature of the world we create. Even ocean activists mostly rely on visual tools in their campaigns, hanging banners and writing screeds, rather than bringing seismic pounding, the shriek of sonar, or the roar of propeller cavitation home to their sources.
I watch the needle track its furrow through the plastic disk. Sound—coming to me through the ocean water of my inner ears—joins me to whale bodies, nerve to nerve, cousin to cousin. We loved you enough to rocket your voices into space. We curtailed our ravening appetites just in time to save the last of your kind. Can we now listen and act, saving you from sonic nightmare?
Cities
From the apartment’s open window come two seconds of whistled melody, then a quiet chitter like an afterthought. A pause for another couple of seconds, then the song repeats, a new arrangement of fluted warbles, crowned with a soft squeak. The song continues for ten minutes, each phrase a variation of whistles and short trills.
A Eurasian blackbird perches on the apartment building’s gutter and casts his song into the courtyard. The paved space is enclosed on all four sides by high walls, and so the sound is trapped, reverberating and bouncing back to me in lush, vigorous tones as I listen from my window on the fifth floor. As he sings, the bare walls are gilded and the cool, dewy air of this May morning glows. Usually, this center courtyard in a Parisian apartment block is an acoustic annoyance, catching and transmitting to every window the clatter of rubbish bins on concrete pavers and the chatter of passing residents. But the blackbird uses this space to his advantage, posting himself at its rim and pouring in his song. This modern open-topped cavern gives a richer, longer reverberation than the one I heard at Geißenklösterle cave, listening to the blackcap. I’m astonished to hear such sonic beauty from a bird in an unexpected place. There are no trees in the courtyard, yet the song blooms here as if in a wooded valley. The French name for the bird, merle, captures some of the spirit of the sound, rolling on the tongue like his introductory whistles. The English name is accurate enough for the charcoal feathers of the male, although he also sports a golden, sometimes amber, beak and a yolk-yellow eye-ring, and the female is dusky brown.
