Sound and Fury
US Navy Threatens Whales to Safeguard Foreign Interventions

International Marine Mammal Project

by Chris Clarke

LFA is intended for use in the world's biologically-rich coastal regions during US incursions into other countries, to reduce the likelihood of politically damaging casualties.

A recently-declassified high-tech US Navy project to aid in detection of hostile sub-marines is shaping up as a major new threat to marine life. Nonetheless, the Navy is pressing ahead with the development of the project amid a growing chorus of opposition. The International Marine Mammal Project has learned that the Navy's official justification for the project is misleading, and that its major purpose is to provide political cover for interventions in foreign countries.

The project, called the Surveillance Towed Array Sonar System Low Frequency Active acoustic sonar system (SURTASS LFA), is designed to take advantage of the special acoustic properties of high-decibel, low frequency sound in seawater to detect what the Navy claims are increasingly quiet foreign submarines.

In years past, the US Navy and its allies have monitored movements of enemy submarines through a network of hydrophones (underwater microphones) placed on the seabed. This net-work, the Sound Surveillance System (SOSUS), proved effective for decades in monitoring the positions of Soviet nuclear-powered submarines in deep water in the Atlantic and Pacific oceans. Additionally, a previous generation of SURTASS ships without an LFA component listened for subs by means of a string of towed hydrophones. However, as propulsion technology advances, the Navy claims that passive sonar will soon prove inadequate to a new generation of quieter subs with redesigned propellers and more efficient power systems.

Enter SURTASS LFA, which consists of underwater megaphones, suspended from ships, that broadcast very loud pulses of low frequency sound into the ocean water. (That's the LFA part.) The sound travels readily through the ocean and echoes off solid objects, submarines among them. (Thus the term "active" sonar, as opposed to a "passive" system that merely listens to sounds the target ships make.) The rebounding sound is then picked up by an array of microphones towed underneath Navy vessels. (That's the SURTASS part.) The signals are then uploaded into ship-board computers, which interpret the echoes to distinguish submarines from rocks, schools of fish and sunken WWII destroyers. The Navy's claim is that SURTASS LFA will allow a fleet to detect even the quietest submarines as they lie on the bottom of the ocean waiting to ambush unsuspecting aircraft carriers.

But of more than three dozen mentions of SURTASS LFA in leading defense trade publications since 1990, none have described the system as a counter to quiet subs in the open ocean. The US Navy wants SURTASS LFA for use in littoral (coastal) anti-submarine warfare (ASW), to protect its ships and crew during interventions in foreign lands, where losing even one Navy sailor may prove politically damaging. And this expensive political cover may come at the expense of the health of marine mammals and other wildlife worldwide.

What SURTASS LFA does
Sound travels much more readily in water than it does in the atmosphere. Some marine biologists have speculated that whale songs emitted off the coast of Newfoundland are audible to whales in the Caribbean Sea. And whatever the medium, low frequency sound carries further than higher-pitched sound. You can hear the bass line in a rap song long before the car stereo responsible moves into view, where the higher notes are often harder to resolve at a mere block or so. Older, passive systems for submarine detection such as SOSUS have long taken advantage of the extreme degree to which low-frequency sound will propagate in water. Diesel-electric submarine engines, the turbines on nuclear subs, prop wash, and the wake generated by a sub under power all create low-frequency vibrations, which we and other living things hear as sound.

The speed of sound in water depends on the water's temperature, salinity, and pressure. When sound travels from warmer surface water past a deeper layer (which oceanographers call the thermic line, often at about 500 meters) that marks a transition into colder water, the speed of that sound wave slows. Like a beam of light through a glass lens, the sound will bend toward the direction in which speed is slowed. At about a thou-sand meters below the surface, the weight of a kilometer of ocean increases the ambient water pressure. Sound travels faster in this highly-pressurized water than in water at normal pressure, and thus at about 1000 meters the emitted sound will start to bend up toward the surface again. Thus there is a layer of ocean in which the sound, reflected in turn between the thermic line and the zone of increasing pressure, can travel for a significant distance. This is much the same phenomenon as fiber optics, in which light bouncing off the walls of the optical fiber is transmitted for remarkable distances and around curves.

Nowadays, the US Navy says that's not enough. Quieter ships, combined with an ambient ocean noise level that grows as more and more merchant ships ferry global commerce across the seas, make it increasingly difficult to find enemy subs as they lurk. True, the submarines once operated by the Soviet Union are now in the hands of people who are probably our friends, but the Navy warns against the day when advanced technology falls into the hands of those whose power might nor be of the super variety. "The danger", wrote Navy Captain N. E. Rondorf in a May 11, 1999 letter to Mark Giese of the Wisconsin Humane Society,

... lies in the proliferation of submarines by nations whose interests may be hostile to the United States and its allies. LFA sonar will allow the detection of these potential threat submarines and provide the ability to successfully defend our forces against the stealthy, well-armed submarine threat. LEA sonar is critical to protect United States sailors, soldiers, ships and equipment.

Rondorf failed in his letter to specify precisely where those hostile subs would be found, and why they might be hostile. As we shall see, these questions prove central to the origin and intend-ed use of SURTASS LFA.

The Danger to Wildlife
Why are representatives of the Wisconsin Humane Society, and of dozens of other animal welfare and environmental organizations, corresponding with the US Navy about SURTASS LFA?

Beneath the top few feet of seawater, the ocean is a dark place. The same water that conducts sound so well scatters and absorbs sunlight. Thirty meters down, human divers find the sea a murky, slightly mysterious place. Not much deeper than that, only the sparse bioluminescence of a handful of creatures provides any light at all.

Any ocean species that relies on remote sensing rather than just waiting for food to swim into its mouth had better find some sense other than vision to rely on. A few, such as the great white shark, have developed extraordinary olfactory senses. Others have invented whole new senses: electric rays are thought to scope out their neighborhood by discharging and then measuring the electrical impedance of nearby objects.

But for most marine species, especially those whose ancestors came from the land with a developed set of terrestrial senses, hearing is the key to the door of perception. Marine mammals in particular are renowned for their sharp ears. Bottlenose dolphins can distinguish between a cube and a sphere of similar size, just by listening to their echoes. A mother humpback whale can keep track of her calf by voice, and vice versa, over a distance of miles.

Imagine being told to drive down to the soccer field and pick up your kid, and to stop at the grocery store on your way back, all the while blinded by a brilliant strobe light. This is mote or less the scenario activists fear: that the deafeningly loud sound pulses generated by SURTASS LFA will prevent marine mammals from feeding, from navigating successfully to calving grounds, from finding members of their families. Animals other than marine mammals are also potentially threatened by SURTASS LFA. Many seabirds are known to be quite sensitive to low frequency sounds in air, and it's a safe bet that diving seabirds such as the common murre are sensitive to underwater LF sound as well. Some species of salmon are repelled by sounds of frequencies less than 150 cycles per second or Hertz (Hz). Other fish are vulnerable to damage in their swim bladders and other organs from certain types of low-frequency sound.

Activists and the Navy disagree as to the subjective intensity of the sound generated by SUR-TASS LFA. On paper, the numbers are apparently unambiguous. Eighteen bathtub-sized speakers, suspended approximately a hundred meters below the hull of the ship, will emit synchronized pulses of sound ranging in frequency from 100 to 500 Hz. The pulses will reach intensities as high as 230 decibels (dB) at the source. (Decibels are calculated on a logarithmic scale; a 20 dB sound is ten times louder than a 10 dB sound, and a 30 dB sound a hundred times as strong. The human nervous system processes sounds on a similar logarithmic scale, which is why a lawn mower in the next yard doesn't sound five thousand times louder than a normal conversation.) Within a nautical mile of the SURTASS LFA array, the Navy says that sound intensities will fall off to below 180 dB, an intensity which it claims poses no long-term threat to marine life.

After sweeping up and down the water column to a point 300 nautical miles away from the source, the noise may still be as loud as 140 dB. Most people find their threshold of immediate pain at about 135 dB. Standing next to a jet engine at full power, you'd be subjected to a noise level of 160 dB. A minute and a half of 170dB sound will cause permanent hearing loss in human ears.

Problems arise in translation from air to water, and from human to nonhuman ears. Sound not only travels further and faster in water than in air, but the relationship between a sound's intensity and the pressure it exerts on objects is different in water. Acoustic scientists disagree as to what level of sound in air would be the equivalent of a 140 dB pulse from a SURTASS LFA array 300 nautical miles away, but most generally subtract 26 dB from underwater sound intensities to find equivalently loud sounds in air at sea level. In other words, sounds in water are about 500 times weaker than subjectively similar sounds in air. However, in its July 1999 Draft Overseas Environmental Impact Statement/Environmental Impact Statement (OEIS/EIS) for SURTASS LFA, the Navy states that due to the relative impedance of air and water (the stiffness or density of the medium) a roughly 5,000 times greater power level (35.5 dB) is necessary in air than in water to produce an equivalent power level. Therefore, 61.5 dB must be subtracted from a sound level in water to produce an equivalent acoustic intensity in air ... [A] 60 dB difference represents a million-fold power difference; so, [sic] it can easily be seen how misleading it can be to try to compare underwater sound that a system like SUR-TASS LFA sonar makes with in-air sound that a jumbo jet makes.

In other words, the Navy disagrees that 26 dB is the correct conversion factor, arguing instead for 35.5 dB, but then - as if to offer a compromise between the two positions - subtracts them both.

Battery by Boom Box
An exact correlation between sounds in air and water may never be agreed upon. However, no one disputes the fact that a 230 dB sound in water poses an immediate and severe threat to humans and wildlife in the vicinity. Ironically, the best existing set of safety standards for exposure to low-frequency sonar comes from the same institution planning to contravene those standards with SURTASS LFA: the US Navy. In Exposure Guidelines for Navy Divers Exposed to Low-Frequency Active Sonar, a 1996 report by F. Michael Pestorius of the University of Texas at Austin and Capt. M.D. Curley of the Naval Submarine Medical Research Laboratory in Groton, Connecticut, the authors describe a diver who was exposed to an underwater low-frequency sound of 160 dB. After twelve minutes, the diver experienced "dizziness, somnolence, irritability to concentrate and residual tingling in arms. He received medical attention on the spot and recovered, only to suffer a relapse an hour after the event and another while driving home from and chronic depression.

Based on this and other examples of adverse human reaction to low-frequency subaquatic noise, the Navy established a 140 dB threshold of safety for human exposure to LF sound. One hundred forty decibels, says she Navy, is the loudest underwater sound to which a diver can safely be exposed.

A sound of 140 decibels is one ten-thousandth the intensity of a 180 dB sound, the Navy's "safe" level for marine mammal exposure to LFAS. The Navy claims that marine mammals, with their extraordinary sensitivity to the slightest sounds, can withstand a sound ten thousand times more intense than that proven to cause human beings immediate and lasting damage.

There is abundant and increasing evidence that the Navy is as wrong as common sense would dictate. On May 12 and 13, 1996, twelve Cuvier's beaked whales beached themselves in a 39 kilometer stretch of the Kyparissiakos Gulf, along Greece's Innian coast. A thirteenth was found in an advanced state of decomposition two weeks later. Cuvier's beaked whales rarely beach themselves: Dr. A. Frantzis, in a short article published in the peer-reviewed journal Nature on March 5, 1998, observed that the NATO vessel Alliance had conducted LFA tests in the Kyparissiakos Gulf beginning on May 11. Frantzis noted "We know that LFAS was used in the Kyparissiakos Gulf. We also know that no other LFAS tests or mass strandings have occurred in the Greek Ionian Sea since 1981. Taking the past 16.5 years into account, the probability of a mass stranding occurring for other reasons during the period of the LFAS tests is less than 0.07%."

A similar incident took place as this article was being prepared, on March 15, 2000, when the US Navy tested active sonar equipment off Abaco Island in the Bahamas. Within two days, thirteen whales had beached themselves on Ahaco, Grand Bahama, and Eleushera islands. The toll included Cuvier's whales, dense-beaked whales, an unidentified species of baleen whale, a minke whale and a spotted dolphin. According to the US National Marine Fisheries Service, two whales were bleeding from the eyes, suggesting acute trauma.

The Navy has denied any connection between the whale deaths and the active sonar tests. However, Michael Breynan, Director of the Bahamian Fisheries Department, told the Associated Press that he was unaware of any similar incident happening before in the Bahamas. Biologist Ken Balcomb, who has been involved in cetacean field research in the Bahamas since 1992, says that one or two whales strand in the Bahamas in an average year.

Scientists and environmental organizations, including Earth Island Institute, are calling on the Navy to suspend all LFA tests while an investigation is conducted into the strandings.

Other SURTASS LFA tests have done damage to whales. In March 1998, two humpback whale calves died after being separated from their mothers during tests of SURTASS LFA off the Hawaiian Islands. (The tests were Phase III of the SURTASS LFA Scientific Research Program (SRP), phases I and II having taken place off the California Coast near San Nicolas Island in fall of 1997, and west of Monterey Bay in January 1998, respectively.) Humpbacks keep track of their young by voice, and any injury to the calves' (or mothers') hearing may have prevented them from reuniting with family members. Contemporary reports in the Honolulu Star-Bulletin described an unusually whale-free whale watching season following the tests.

Low-frequency noise need nor kill an animal outright to do damage to the marine ecosystem. As noted, whales and other marine mammals rely on their hearing to feed and breed. Even if a whale is not mortally wounded by the intense shock of an LFA "ping," any hearing loss the whale suffers as a result may keep that whale from finding food, traditional breeding grounds, or members of its pod. As Benjamin White Jr. of the Animal Welfare Institute puts it, "A deaf whale is a dead whale, but it can rake a very long time to die."

Animal activists and marine biologists say that even a few uses of an LFA system could damage populations of marine species past the point where recovery is likely, and fear that such damage may not be visible for weeks or months after the boom goes off They decry the fact that the Navy's Draft OEIS/EIS claims SURTASS LFA poses no overwhelming threat to cetaceans or other wildlife, despite the fact that the Navy's tests included no long-term monitoring of animals in the test areas. Migrating gray whales swerved dramatically off their normal route while LFA SRP phase II was in progress near San Francisco Bay, and again during the next winter's southward migration. During phase I of the SRP in the Channel Islands area, researchers noted that fin and blue whales respond-ed to the pings by decreasing the number of their vocalizations: shutting up, in effect. Cetacean biologist Lindy Weigart of Canada's Dalhousie University notes that "we don't even know what these vocalizations are used for, but the best guess is that they are important in mating. A decrease in calling whales ... could easily translate into fewer mares being located and thus a decline in population." In a response to the draft OEIS/EIS, Weilgart said "The most biologically significant effects are on population parameters such as birth rate, growth rate, death rare, etc. These are largely unknown, and moreover unknowable, for most populations of cetaceans. A very limited, short-term study... would certainly nor even begin to address such questions of biologically significant impact."

It is instructive to note that despite the marked effects the LFA SRI? activities had on marine mammals, none of the SRP test pings even reached intensities as high as 160 dB at the source. SURTASS LFA's planned operating intensity, as noted before, is 230 dB: ten million times more intense than 160 dB.

The Navy has responded to concerns about SURTASS LFA's potential for devastation of marine life by agreeing to a couple of mitigations, including attempts to monitor for the presence of marine mammals by high-frequency sonar and shutting down the system in their presence, a proposition of dubious likelihood during hostilities. At the forefront of the Navy's environmental promises is a stated commitment to refrain from using SURTASS LFA in proximity to the coast-lines of the world, where much of the oceans known biological diversity lies. A technical report for the SURTASS LFA EIS prepared on the Navy's behalf (and with Navy funding) by scientists at the University of California, Santa Cruz's Institute of Marine Sciences, baldly and repeatedly states that SURTASS LFA will not be used in near-shore waters, thus minimizing the effects on the biologically-rich littoral (coastal) environment. The Draft OFIS/EIS says that the Navy won't be using SURTASS LFA anywhere where a signal of 180 dB would be detectable within 12 nautical miles of land.

Looking at these assurances, and at the map in the OEIS/EIS of SURTASS LFA Sonar Potential Operating Areas (see graphic), one could logically reach the conclusion that SURTASS LFA is intended for use in the open ocean, much as SOSUS was used to detect the Soviet submarines of a generation ago. This conclusion would be reached in error. SURTASS LFA is intended, and has apparently always been intended, for use along the world's coastlines.

Going Coastal
In 1982, during the Falklands Islands war, an Argentinean fighter plane fired an Exocet missile at the British ship Sheffield, sending it to the bottom and killing twenty sailors. The incident propelled the navies of the world - or at least those whose governments insisted on invading other countries - to adjust their expectations of the kinds of risks they would face in wartime. The subsequent demise of the USSR capped this sea change in naval strategy. As the nature of naval warfare shifted from a long-term game of chess on the high seas to something more closely resembling Whack-A-Mole, anti-submarine warfare strategy and equipment came up lacking. Passive low-frequency sonar had been, and still is, adequate for detection of even the quietest submarines in deep water. Despite the increasing noisiness of the world's oceans, an undisputed fact which the US Navy advances as justification for SURTASS LFA, marked advances in computing and remote sensing more than make up for any increased masking of submarine noise. In February, 1997, the US Navy's Director of Submarine Warfare Rear Admiral Edmund Giambasriani told Janei Defense Weekly, "Our view is that because of significant capabilities in processing, sensor apertures and the ability to net sensors together, passive is nor dead ... We feel there is [sic] still a lot of dB out there that we can mine."

On the continental shelf, it's a different story: passive sonar has never been effective in the littoral (coastal) environment. Shallow water, contorted rocky coastlines, and changes in salinity near estuaries and lagoons have been a source of frustration for anti-submarine warriors relying on sonar. Inconsistencies in the acoustic medium make passive sonar next to useless in the littoral environment. As long as littoral warfare remained a sideline to the main event on the high seas, this technological blind spot was considered not much more than an annoyance. But as littoral anti-submarine warfare moved to center stage, discussion of active sonar began in earnest, and that's when the LFA component was added to a SURTASS that had worked just fine on the open ocean. As Norman Friedman put it in a June 1, 1995 essay in International Defense Review:

During the Cold War, the major navies were concerned mainly with countering nuclear-powered submarines, often (though not always) in deep water, where low-frequency, long-range [passive] sonar was the best sensor. Further, had a Third World War actually broken out, Western navies would have hunted Soviet submarines anywhere in the world's oceans, attacking them whenever they were found and, given the scale and scope of the war, errors would have been acceptable. Today, from a technical point of view, the threat now coincides quite closely with that faced by smaller navies for many years: diesel-electric submarines operating in coastal (littoral) waters. In addition, a limited operation against a Third World country entails different rules, and operations are likely to be geographically constrained and may be short of war, so that a potentially hostile submarine will have the initiative. Indeed, attacks which are premature or which accidentally sink other countries' submarines will cause grave diplomatic problems, possibly even leading to the operation being terminated.

Of the many references to SURTASS LFA in defense trade publications throughout the 1 990s, none - zero - have mentioned a use other than protecting US Navy ships as they enter the littoral waters of hostile foreign nations. There are no references to combat on the open ocean, nor to defending the coasts of the United Stares. LFA is, and has always been, intended for use in the world's biologically-rich coastal regions during US incursions into other countries, to reduce the likelihood of tactically acceptable but politically damaging casualties. The US Navy has weighed the extinction of marine mammals against perennial political inconvenience, and decided in favor of politics.

There are plenty of places where continental shelves extend far enough from the coast that the Navy could illuminate the shallow water while remaining outside their "180 dB at 12 nautical miles" limit. There are also plenty of places in the world where the shelf is only a narrow strip along the coast, or where broad shallow seas hold such diverse marine life that an arbitrary 12-mile limit means little in any biological sense. Such places include potential political hot spots like the west coasts of Ecuador and Peru; the horn of Africa; the Bay of Bengal; the East China, South China, and Yellow seas; the Adriatic and Ionian seas; the Red Sea; and the Persian Gulf. It is possible that the US Navy, out of a deep and abiding respect for marine life and the sanctity of its promises, will refrain from ever using SURTASS LFA in such vulnerable areas. It is far more likely that the exigencies of combat and - so be fair - an officer's concern for the safety of the personnel under his or her command will outweigh concern for wildlife. Once SURTASS LFA is deployed, it will be used wherever it is deemed necessary.

SURTASS LFA is not the first or only example of a technology injurious to wildlife created to sup-port an interventionist foreign policy. It may, how-ever, be the first time a weapon other than strategic nuclear arms threatens the inadvertent extinction of a whole raft of species. Viable alternatives to LFA exist in the field of littoral antisubmarine warfare. ASW helicopters, intelligent torpedoes, and other tech solutions have been advanced as LFA -replacements. There is also the radical notion of forestalling the conflict before it begins, by refraining from selling diesel-electric submarines to nations we know we'll likely be invading, or by reconsidering the lost art of diplomacy without gunboats to back is up. Only public opposition to SURTASS LFA will force consideration of these alternatives. Whether the Navy sacrifices marine mammals out of fear of stateside political opposition to its operations depends largely on the voices of the US citizens the Navy so fears.

What You Can Do: Please write or call your Representative and Senators, urging them to DEFUND the Navy's LFA program (if you do not know who your members of Congress are, contact your local Registrar of Voters or City Hall; the Congressional switchboard is (202) 224-2121). Send the same message by writing or calling President Bill Clinton, The White House, 1600 Pennsylvania Ave., Washington, DC 20500; (202) 456-1414 or e-mail <president@whitehouse.gov>. For more info, send your e-mail address so IMMP <marinemammal@earthisland.org> and ask to be put on our special LFA alert list.