In the most severe cases, where the noise exceeds a level of tolerance, many species of whales and seals will beach themselves and die. Because sound introduced into marine environments can travel very long distances if unimpeded by landmasses, underwater mechanical or electronic noise can present special problems. This is apparent, for example, when assessing the impact of the excessive levels emitted by U.S. Navy Low Frequency Active Sonar (LFAS), which is thought to be a contributing factor to the deaths of Cuvier’s beaked whales in both the Bahamas and the Mediterranean. Shortly after the sinking of the Titanic in 1912, researchers in the U.K. and Canada began experimenting with low-frequency ranging devices and developing a primitive class of oscillators and hydrophones that were used to detect submarines at the beginning of World War I. By World War II, mine and ship sonar (an acronym for Sound Navigation and Ranging) technology had vastly improved, with fairly accurate reception. As with bat echolocation, sub acousticians would send out a ranging signal that, when it bounced off a distant object, could help determine (by the returning difference signal) the object’s distance and if it was static or moving. And, if moving, approximately in what direction and at what speed.
Breakthroughs in advanced naval ship design and construction during the Cold War made vessels much quieter and thus harder to identify; with those changes, more accurate detection equipment became necessary. By the 1980s, the U.S. Navy decided that the best alternative to the older models was the new LFAS. Without any environmental impact statement (EIS), the Navy bypassed the usual permitting required under the Endangered Species Act (ESA) and the National Environmental Policy Act (NEPA) and began testing. By 1996, after an increase in multiple whale beachings and public outrage, the Navy agreed to a review by a team that would evaluate the environmental response to the sound, in particular by marine mammals. Called the Scientific Research Program (SRP), the team consisted of both government and academic members. The output from the Navy’s systems, the team determined, was reported to be in excess of 235 dB. At three hundred miles from the source, it still retains an intensity of 140 dB, potentially harmful and even lethal to many marine organisms within range. In 2003 a federal court judge in San Francisco mandated that the Navy reduce the system’s use so that ocean wildlife would not be harmed.
In 2001 Ken Balcomb, a whale biologist and founder of the Center for Whale Research located in Friday Harbor, Washington, wrote an open letter to the LFAS program manager. In Balcomb’s words:
When Cuvier’s beaked whales are exposed to high intensity sonar at their airspace resonance frequency via LFAS or midrange sonar it can be painful and life threatening. Envision a football squeezed to the size of a ping-pong ball by air pressure alone. Now envision this ping-pong ball compressing and decompressing hundreds of times per second. Imagine this ping-pong ball located in your head, between your two ears. This is what the Cuvier’s beaked whales experienced as a result of the Navy’s sonar testing in the Bahamas in March 2000. Airspace resonance phenomena resulted in hemorrhaging which caused the stranding and deaths in the Bahamas.
The lethal impact of the LFAS signal—which can transmit extremely high levels of signal from twelve to sixty miles—affects beaked whales and other marine creatures such as dolphins, minke whales, killer whales, and fish.
But sonar is not the only anthrophonic source that affects marine life. While I was working on my doctorate, I was involved in a study done for the national parks in Glacier Bay, Alaska. We wanted to determine why, despite ample food resources, humpback whale populations in the bay were declining. Humpback whales were seen swimming away from the perceived danger of large tourist vessels that generated huge amounts of propeller and engine noise, and hiding in the acoustic shadows of island land-masses or large bodies of calved ice. The report concluded that uncontrolled loud vessel noise had been at least one of the major probable causes of the population decline. For several years the report wasn’t made public because, according to Charles Jurasz, a biology teacher and naturalist from Juneau and the principal investigator of the study, the National Park Service was ordered to quash the findings by James Watt, then secretary of the interior. Given the negative impact it might have on tourist-vessel traffic in the bay, the park service complied with the order. Jurasz was never again allowed into Glacier Bay to confirm his data or to do a follow-up study. When I asked if he had tried, he told me that he had many times but was unable to obtain the necessary permit to continue his work. The rejection left him devastated. Nevertheless, Jurasz’s groundbreaking humpback-whale bubble netting and identification efforts were recently honored by the National Oceanic and Atmospheric Administration.
Over the past few decades the noise emitted by commercial vessels in Glacier Bay has been somewhat mitigated with vessel engines, hulls, and propellers designed to generate less vibration. And recent reports show that the whale populations have returned to “near normal” numbers. Allison Banks and Chris Gabriele, National Park Service employees at Bartlett Cove in Glacier Bay, told me in June 2010 that the humpback whales are once again thriving.
In a recently published study on marine anthrophony, Hans Slabbekoorn of the Institute of Biology at Leiden University in the Netherlands demonstrated that loud industrial sounds of short exposure—like blasts and sonar pinging—can harm fish. Unlike marine mammals that receive and process sound and vocalize, many fish species have two organs that detect marine pressure waves, as mentioned earlier. One is the inner ear—they have no middle or outer ear—which can detect frequencies into the thousands of hertz. The other is the lateral line—a thin organ that runs in a straight, narrow line from the gill to the tail—which picks up low-frequency sound waves, usually those below 100 Hz.
Noises with longer exposures potentially impact larger areas and numerous species. Slabbekoorn noted that:
Recent experimental evidence has unequivocally shown that sounds can modify mate choice decisions in fish. Female haplochromine cichlids provided with a choice between two males, matched in size and color, preferred to interact with the male associated with playback of conspecific sounds … [but] the sounds of passing boats were inferred to reduce detection distances by up to 100 times. Masking, leading to a reduction in detection distance, or the so-called active space, can lead to failure in mate attraction.
So, noise can affect sexual selection, breeding cycles, and population dynamics—but exactly to what extent remains unclear.
Several publications have resulted from current National Park Service noise studies. Among the recent studies in 2009 and 2011 are those by Jesse Barber, Kevin Crooks, and Kurt Fristrup, which examine the effects of noise on what is referred to as the “effective listening area,” the territory over which animal vocal signals carry so that they can be heard and responded to. Each points out in different ways that even though minimal levels of noise were observed (such as a 3 dB increase from a wind farm, aircraft, or road traffic), the impact reduced the listening area (the ability of the study animals to receive their respective biophonic signals) by 30 percent. These studies are important because they go beyond the former tendency to concentrate obliquely on issues of noise vis-à-vis what humans are able to discern with the aid of technology or by real-time listening. In other words, previous focus concentrated on “audible noise” emanating mostly from aircraft without addressing the core questions of animal impact, causal behavior, and the effect on visitor experience. Instead, these new studies begin to address the ways in which anthrophony affects living organisms across all species lines and what specific classes of aircraft (or other) noises affect animal behavior and visitor experience. By finally embracing these fundamental issues, researchers have begun to examine evidence of cause and effect on a grander scale, taking seriously the idea that different species are affected by different types of noise, in different ways, at different times of day and night, and over the seasonal course of each year.
One late-fall holiday when I was a child, my parents took my sister and me to the snow-cover
ed valleys of Yellowstone National Park. From where we stood, midway between the park entrance at West Yellowstone and Old Faithful, overlooking a wide valley, a complete absence of human noise engulfed us, even close to the road: a stillness punctuated by an extensive repertoire of ravens and the vocalizations of jays, magpies, horned larks, elk, and other four-legged creatures that were drawn to lower elevations by better prospects for protection and food. At moments, it was so still that we could locate organisms from the sounds of their breath, faintly detected over distance across the snowy fields. Even more subtle was the softer texture of space created by the hush of faraway streams and the slightest breezes diffusing through the upper reaches of the conifers. I dream of that enchanting moment still.
The last time I visited—February 2002, standing in the same spot where my parents had lingered beside the road to hear the winter over half a century ago—the magic was entirely gone, obliterated by engine noise and smog. More recently, the snow-mobile issue has been moderated to some extent by restrictions on noise and speed, four-cycle technologies, and the number of vehicles allowed in the park at any one time. But nobody’s completely happy. At one extreme—if you can call it an “extreme”—environmentalists don’t want any snowmobile or straight-piping motorcycle noise in the parks. Snowmobilers don’t like being confined to the park’s speed restrictions and the necessity of traveling in convoys, thus having a government agency restricting their individual “freedoms.” At least there is an option: there are two thousand miles of open, unrestricted national forest trails just outside the park boundaries in West Yellowstone. But for the promise of some tranquillity in the park itself, there is no such similar haven outside its protective borders for the rest of us and, without a long hike, relatively little within.
National parks are protected areas—it takes an act of Congress to establish one—yet anthrophony, such as snowmobile noise at Yellowstone, has been a problem at many nonurban U.S. national parks.
At Grand Canyon, noise from sightseeing flights and the whistling tourist steam train that travels along the rim intrudes into any awestruck reverie one might otherwise enjoy while standing above or hiking within the chasm. The pictures of the park really do convey only a tiny fraction of the experience.
And in Grand Teton National Park, a regional airport is situated midway in the valley that defines Jackson Hole. It’s the only such airport located within national park boundaries. The Jackson tower releases as many as twenty flights an hour between six a.m. and eleven p.m., repeatedly annihilating the natural soundscape of one of the most beautiful spots in America. (The bulk of the flights are private; the airport in 2007 handled only about seven commercial flights each day.) In California’s great Mojave Desert, dune buggies and dirt bikes fracture the natural quiet at many sites.
Still, there have been rays of hope. We are beginning to understand—albeit late in the game—that pristine natural soundscapes are reserves and resources as much as unimpeded sight lines and are just as critical to our enjoyment and awareness of the natural wild world. When sole federal authority for noise control fell under the aegis of the Federal Aviation Administration in 1982, the National Park Service was left struggling to deal with its noise issues. However, recognizing the crucial link between humanity and the soundscapes of the wild, a couple of activists within the NPS initiated a strong educational and administrative model to protect natural soundscapes as a valued resource.
The late Wes Henry and his colleague Bill Schmidt undertook this radical feat through a series of below-the-radar meetings and incremental steps beginning in the mid-1990s and concluding in 2001. For a short time within the NPS acoustic program, wild soundscapes were treated as a component of great value worth preserving for visitors and creatures alike. Henry, Schmidt, and a few others who later joined the program recognized that there were vast areas within the parks where soundscapes could still be enjoyed. Visitor reaction to the noise in the national parks convinced enough NPS and Interior Department employees that it was important to attempt to hear and treat soundscapes differently—as necessary to visitor enjoyment as the informed management of wild critter life and the habitats in which they thrive.
Efforts like these have had some positive results: snowmobiles have been moderately controlled and monitored in Yellowstone; tourist overflights in Rocky Mountain National Park have been pretty much eliminated; and flights over Grand Canyon have varying restrictions on a certain number of aircraft, areas, times, and conditions that the FAA and the NPS review and change from time to time, pretty much determined by the political climate in Washington at any given moment. Recently, tourist sightseeing aircraft noise in Grand Canyon has gotten much worse: as of this writing and according to the Grand Canyon Chapter of the Sierra Club, it is estimated that the daylight tourist overflight aircraft noise has increased to the point where 75 percent of visitors hear aircraft 100 percent of the time, and the remaining 25 percent hear it a minimum of 60 percent of the time in all but the most remote areas of the park. However, given the sweeping changes in priorities since 2000—when George W. Bush was elected president—and a current focus on other, more pressing matters, the ultimate fate of these policies remains uncertain, since the original directive under which they were implemented expired in 2004. Depending on the political climate of the moment, the resistance of many in government to environmental protections means that, at least in the near term, there is a high risk that activities such as the visitor soundscape program will not continue to be supported in the visionary ways they were originally intended.
In fact, I’m convinced that the concept of natural soundscapes represents a threat to some people. At one point, I was commissioned by Wes Henry to write the visitor soundscape activity plan for the program. Titled Wild Soundscapes in the National Parks: An Educational Program Guide to Listening and Recording, its agenda was, at first, administered under the “Natural Soundscape Program” moniker. The goal of the program was to preserve natural soundscapes within park boundaries as much for a more complete visitor experience as for wildlife protection, and its mandate extended within the parks and to some other Department of the Interior (DOI) areas. It gave large populations of folks accessibility to the sounds of the natural world many would not otherwise have been able to enjoy. But the name, Natural Soundscape Program, was changed in 2004 to the Natural Sounds Program—a neutered term evocative of nothing in particular—and the targeted visitor focus all but disappeared along with the title change.
On the surface, altering a name seems inconsequential enough. But the event did not come about without some powerful influence from outside the DOI, with the result that the change emasculated much of the insightful work that had preceded it.
Secretary of the Interior Gale Norton had been urged by Alaska representative Don Young, then chairman of the House Appropriations Committee, and his colleague Richard Pombo, the ex-representative from the 11th district of California, to alter the name. They felt that the term soundscape was too loaded (translation: “green,” although the etymological roots of the word have no more political or social resonance than the words landscape or seascape).
Howie Thompson, a friend and part of the NPS soundscape program during the height of its development and subsequent discussions before he retired, recalled that because of the political pressure in early 2004 (a consequence of the Young-Pombo letter in November 2003), within a number of weeks of the new year, word had filtered down from Norton’s office, apparently through Fran Mainella, then director of the National Park Service, advising the group that it would be wise to change the name to the Natural Sounds Program. Don Young, also chairman of the Committee on Transportation and Infrastructure—the group that oversaw the Department of the Interior—called the shots and spoke plainly about his contempt for restrictions on open public spaces and for those who tried to implement them. An impression of Young’s passion can be found in a 2006 Rolling Stone article, where Young is quoted as saying that “environmentalists are
a self-centered bunch of waffle-stomping, Harvard-graduating, intellectual idiots” who “are not Americans, never have been Americans, never will be Americans.” During a debate on native Alaskans’ right to sell the sex organs of endangered animals for the purpose of aphrodisiacs, he pulled out an eighteen-inch penis bone of a walrus and brandished it like a sword on the House floor.
When initiated by Wes Henry and Bill Schmidt, the NPS soundscape program was astute and two-pronged. One component concentrated on abating noise introduced by tourist helicopters, fixed-wing aircraft, and ground-level modes of transportation. The second dealt with protection of natural soundscapes for their own intrinsic value and involved comprehensive visitor programs and activities focused on the subject of soundscapes. This second component was a crucial step in making people aware of the importance of preserving them. During the Bush II administration, however—and according to Howie Thompson, fueled by the Young-Pombo warning letter to Norton—the visitor component of the Natural Soundscape Program was sidetracked, diminished, and, except for a small web presence still in place, minimally implemented. At the same time, federal funding resources directed to the national parks were reduced substantially, the underlying political idea at the time being that most operations within the system could be outsourced and privatized. Where the soundscape concept had been originally framed for visitors as an important resource, for several years that focus did not have the same sense of import within the agency. In the spring of 2011, there appeared to be a shift in direction when the NPS Natural Sounds Program office in Fort Collins issued an internal interpretative handbook titled The Power of Sound, designed, once again, to introduce the public to a natural soundscape overview.
The Great Animal Orchestra Page 18
