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NRDC, allies mount new legal challenge to Navy sonar

Effects of Noise on Wildlife, News, Ocean, Sonar Comments Off on NRDC, allies mount new legal challenge to Navy sonar

2012 is shaping up as the year when the legal battle over the US Navy’s active sonar systems ramped back up to full-scale confrontation.  A 2009 agreement between NRDC and the Navy put legal challenges on the back burner – actually, entirely off the stovetop – in favor of dialogue.  But recent permits issued by NOAA’s National Marine Fisheries Service (NMFS) are now being attacked for the small sizes of the off-limit areas.  NRDC has continued to call, in pubic and presumably in private, for the Navy to keep their sonar activity out of biologically important areas as they move forward with both low-frequency (LFAS) and mid-frequency (MFAS) active sonar deployments.  This week, a new set of rules to govern LFAS was challenged in federal court on the grounds that the exclusion zones are far too limited.  In January, a similar challenge was filed for existing MFAS permits issued by NMFS; see this earlier AEI coverage for details on the MFAS action.

The new suit, like the January one, differs from the initial round of sonar challenges in that the target is the NMFS permits, rather than the Navy’s operations.  As you may recall, the Supreme Court ultimately ruled that Naval priorities deserved wide latitude in the interpretation and implementation of environmental laws.  By challenging NMFS’s analysis of the risks and the mitigations included to protect marine wildlife, these challenges may well take a different path through the legal maze.

The new LFAS rules allow the Navy, for the first time, to operate the high-power sonars in most of the world’s oceans.  The previous 5-year planning process focused on the western Pacific (in part due to the US stategic focus/concern on China and North Korea, and in part due to legal pressure during that round of planning).  A previous AEI post goes into some detail on the new LFAS “letter of authorization,” which covers the first year of the 5-year period (short version: during the first year, operations will remain predominantly in the western Pacific, with a couple of operations north and south of Hawaii).

In a statement, NRDC says:

Because a single LFA source is capable of flooding thousands of square miles of ocean with intense levels of sound, the Navy and NMFS should have restricted the activity in areas around the globe of biological importance to whales and dolphins.  Instead, they adopted measures that are grossly disproportionate to the scope of the plan – setting aside a mere twenty-two “Offshore Biologically Important Areas” that are literally a drop in the bucket when compared to the more than 98 million square miles of ocean (yes, that’s 50% of the surface of the planet) open to LFA deployment.  The apparent belief that there are fewer than two dozen small areas throughout the world’s oceans that warrant protection from this technology is not based in reality.

NRDC also stresses that the LFAS is loud enough to remain at levels that can cause behavioral disruptions at up to 300 miles away.  The Navy has said that take numbers, especially takes for injuries or death, will be low or zero once mitigation measures are implemented, though the permits allow for some of these “Level A” takes; for the first year, they are authorized to kill or injure up to 31 whales and 25 seals and sea lions.

On the water with orca D-tag research crew

Bioacoustics, Effects of Noise on Wildlife, Ocean, Science, Shipping Comments Off on On the water with orca D-tag research crew

Oregon Public Broadcasting recently sent reporter Ashley Ahearn out with the researchers that are listening in on orca activity underwater (covered here last month), and her wonderful, detailed report is now online; check it out!  It includes two videos, one showing a tagged orca’s swimming track, along with every boat in its vicinity over the several hour journey, and the other offering a “poles-eye view” of attaching the D-tag to an orca:

Judge OK’s construction of Undersea Warfare Training Range near right whale habitat

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A US District Judge has ruled against NRDC and others who had challenged the Navy’s permit to build an instrumented training range off the coast of Georgia and Florida, claiming that construction should not proceed until the Navy completes the full EIS for the training activities that will take place there.  Construction is slated to begin within a couple of years, with training commencing sometime around 2018; the range would have about 300 sensors installed on the ocean floor over an area of about 500 square miles, and would host training missions involving submarines, surface ships, and airplanes.

The Undersea Warfare Training Range (USWTR) would begin 50 miles offshore, while a key winter birthing and nursing ground for North Atlantic right whales extends out to 20 miles offshore.  Only about 400 North Atlantic right whales remain, with ship strikes being a major concern, along with the effects of any additional stress on mothers or young whales near the Navy’s operations. “We understand that’s the right whale’s critical habitat,” said Jene Nissen, the range’s program director. “We looked at the type of effects that training could have on right whales, and we are confident it will be very minimal.”  Construction will be suspended from November to April, when the whales are migrating and congregating in the birthing grounds, but the Navy has not agreed to suspend training in those months, or to comply with offshore speed limits imposed on private and commercial ships, saying that this would interfere with their ability to carry out realistic and effective training.

The groups that filed the suit in 2010 are considering an appeal; Sharon Young of the Humane Society of the United States stressed that “We certainly would never argue to undermine our national defense, but it’s also reasonable to ask the military not to jeopardize a species that is just barely hanging on.”

See more AEInews coverage of the USWTR here.

Navy receives NMFS OK for LFAS operations 2012-2017

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In August, the National Marine Fisheries Service issued its Record of Decision that will allow the Navy to operate its Low Frequency Active Sonar systems for the next five years.  NMFS will issue a new Letter of Authorization each year, in order to accommodate new information as needed, but the overall parameters of the permits will remain essentially the same throughout the five years.

AbleWEBWhile the Final Rule allows the Navy to operate the SURTASS-LFA sonar in most of the world’s oceans (Pacific, Indian, Atlantic Oceans and Mediterranean Sea), the Navy’s operational plans for the first year remain centered in the western Pacific, given its particular focus on tracking Chinese submarines (see previous AEI coverage of tensions with China over LFAS surveillance).  Only four missions are planned in other areas, and all these will take place in north and south of Hawaii. The Navy has four ships outfitted with the SUTASS-LFA sonar; three (USNS Victorious, Effective, and Able, seen at left, appear to be based in the Pacific, and one (USNS Impeccable) in the Atlantic; each ship could operate for up to 240 days and transmit SURTASS LFA sonar for up to 432 hours per year (the ships transmit sound roughly 7.5% of the time they are operating).

The Rule and the Letters of Authorization allow the Navy to cause temporary behavioral effects (a “Level B Harassment,” defined as animals hearing the low-frequency sonar at levels ranging from 120-180dB, possibly changing their behavior) on 94 species, with no more than 12% of any regional stock of each species being exposed to the sonar in any given year.  The Navy anticipates, based on species abundance in each of the eleven designated operational areas for the first year, that for most species, the percentage will be far lower: usually well under 1% and topping out at 3% for a handful of species in the 9 western Pacific operational areas; around Hawaii, several species will see 1-3% of the population having behavioral impacts, with a handful of species topping out at 6-7%.

Few animals are expected to be close enough to be injured, and the Navy and NMFS presume that physical harm (Level A Takes) will be avoided completely thanks to various mitigation measures, including marine mammal observers, passive acoustic monitoring, and power-downs when whales are close.  But given the uncertainties, NMFS is authorizing injurious or lethal takes of up to 31 whales and 25 seals and sea lions.

The previous five-year LFAS permits, issued in 2007, faced a court challenge based largely on the ways that the Navy and NMFS designated offshore biologically important areas (OBIA), and on the idea that nearshore exclusion zones should extend at times beyond the 12 nautical mile zone covered by those permits.  Most designated and potential Marine Protected Areas (340 of 403) are already within 12 nautical miles of coasts, so are protected from high-intensity ensonification; a more thorough examination of the rest led to the inclusion of one additional OBIA in this round of permitting, with two more being monitored for possible inclusion as more research is done in them (many were omitted because the species of concern in those areas are high- and mid-frequency vocalizers, and LFAS sounds will have more of an effect on larger whales that hear lower frequencies).  A total of 22 OBIAs are designated worldwide, some considered important year-round, and some seasonally.  Sonar sounds must be below 180db within an area extending 1km beyond the boundaries of the OBIAs (thus aiming to keep sounds under 175dB within the OBIAs); likewise, the same 180dB maximum will apply at the boundary of the 12 nautical mile coastal zone.  The Federal Register notice of the Final Rule contains many pages of comments from the NRDC, Marine Mammal Commission, and others, along with responses from NMFS.

German offshore wind construction aims to limit noise impact on porpoises

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Aggressive offshore wind energy plans in Germany are pioneering innovative new approaches to reducing the noise impacts of wind turbine construction, according to a recent Bloomberg News article.  It’s a good, long piece, well worth a read.  A few highlights:

“Quite a large proportion of our sea area will probably be used for offshore wind farms,” said Hans-Ulrich Rosner, head of the Wadden Sea Office for WWF in Germany. “This will have a serious impact on nature, which needs to be mitigated.”  Harbor porpoises, common in the North and Baltic Seas, appear to be especially sensitive to noise, adding to the challenges. 

Construction of the 108 MW Riffgat offshore wind project is nearing completion; it’s been utilizing a double-walled, water-filled casing in which bubbles are produced to absorb some of the sound from pile-driving of the turbine foundations into the seabed.  In addition, a less intense vibration method is being used for almost half the depth of the piles, with the louder hammering of classic pile driving being used for only the last 40 meters.  These noise reduction techniques amount to half of one percent of the total cost of the wind farm.

Germany’s Federal Maritime and Hydrographic Agency, or BSH, has set a noise limit of 160 decibels for 750 metres around offshore wind construction work. Developers regularly overshoot the limit, which is not applied to detonating old bombs, the BSH’s Christian Dahlke said.  “Our regulations are creating a new industry,” Dahlke said. “If environmental rules to protect animal life are tightened in other countries as well, our companies may even export these technologies.”

At the Nordsee Ost project, a large hose perforated to produce a curtain of air bubbles around each of the 48 turbine foundations to absorb the noise from pile driving, which “brought the noise level much closer” to the 160 decibel cap.  But RWE, a utility involved in the project, said that more research and development is needed “to meet the limit reliably in the future.”

New paper quantifies shipping noise impact on whale communication space

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The latest paper to be published by the research team that’s been studying noise levels in and around the Stellwagen Bank National Marine Sanctuary concludes that in the waters off Boston, increasing shipping noise has reduced the area over which whales can hear each other to about one-third of what it used to be.

“We had already shown that the noise from an individual ship could make it nearly impossible for a right whale to be heard by other whales,” said Christopher Clark, Ph.D., director of Cornell’s bioacoustics research program and a co-author of the work. “What we’ve shown here is that in today’s ocean off Boston, compared to 40 or 50 years ago, the cumulative noise from all the shipping traffic is making it difficult for all the right whales in the area to hear each other most of the time, not just once in a while. Basically, the whales off Boston now find themselves living in a world full of our acoustic smog.”

Below: Ship tracks for one month, in and out of Boston; Stellwagen Bank National Marine Sanctuary outlined in white, bottom-mounted recording units in yellow. (Graphics from NOAA’s Passive Acoustic Monitoring website)

Sb nopp ais tracks

“A good analogy would be a visually impaired person, who relies on hearing to move safely within their community, which is located near a noisy airport,” said Leila Hatch, Ph.D., NOAA’s Stellwagen Bank National Marine Sanctuary marine ecologist. “Large whales, such as right whales, rely on their ability to hear far more than their ability to see. Chronic noise is likely reducing their opportunities to gather and share vital information that helps them find food and mates, navigate, avoid predators and take care of their young.”

Nine hours in Stellwagen:

Sbnms nopp ani

Kathy Metcalf of the Chamber of Shipping of America said her group has no doubt noise is increasing and affecting the whales. But measures such as slowing down ships or retrofitting them with new, more efficient propellers are costly and may not even work, she said. A better remedy would be devising and incorporating quieter designs in the hulls and propellers of new vessels.  “We’re kind of a slow industry,” Metcalf said. “But the bottom line is if we could do something now that can be used as guidelines for new construction, 15 years from now, half the world’s fleet would have already been built that way.”

Bonus:  2010 Science magazine audio interview with Leila Hatch, lead author of the new paper.

Listening to the undersea world

Ocean, Science Comments Off on Listening to the undersea world

A great post over on Artemia, a University of British Columbia blog, from Jessi Lehman, reflecting on listening to the LIDO online undersea sound streams.  Go read the whole thing for sure!

A teaser:

…These ocean observatory networks are about science and whale conservation but also about industry, development, and geopolitics.

But I want to come back to the experience of listening. What is it, exactly, that we hear? Mostly just faint static, like the sound of rain falling. Mostly I find myself listening in apprehension, for what could be there. Some would call this kind of undersea listening remote sensing, but it feels more like interspecies or even otherworldly eavesdropping. To be honest, it feels a bit weird. And it’s not just that I’m so far from the ocean, in a place dry and hot and decidedly un-marine. I can’t say that I understand the undersea environment better by listening to these sounds (though I can’t preclude the possibility that on some level I do). Mostly I am made aware that this is a world I don’t know, can’t know, and can only access thanks to complex technological mediations – and even then only marginally. This makes the experience of listening even stranger.

French philosopher Jean-Luc Nancy writes “to be listening is always to be on the edge of meaning”…

Quite of few of the posters on Artemia seem to be giving a lot of consideration to sound.  Of special note is this project preview from a student who’s right now on the central coast of British Columbia aiming to bring some of Steve Feld’s ideas about acoustemology into the underwater world of cetacean sound-making:

My project puts the concept to work at a whale research laboratory, Cetacea Lab, located on a remote island in Caamaano Sound, Northern, BC. Through a seven-week fieldwork residency (August- September 2012), I hope provoke thoughts on how broader knowledges relate to sustained acts of whale listening. In particular, I will pursue two questions 1. how work in acoustemology, hitherto focused on Indigenous encounters in the developing world, can be challenged and extended by an outdoor laboratory science setting, (Feld, 1996, 2003; Daniels, 2008; Maxwell, 2008; Ramnarine, 2009); 2. to understand how Cetacea Lab’s activities produce an acoustemology of Caamano Sound and its environs.

The central actors of the pilot study are the scientists who conduct Cetacea Lab’s activities. Since 2001, Cetacea Lab scientists have been monitoring whale activity through a network of radio-linked hydrophones, remote observation, and boat-based surveys. Every summer, their efforts are supplemented by two groups of volunteers (5-7 per group), who live at Cetacea Lab for 6-8 week periods (May-July; late July-September). These volunteers provide crucial support for the monitoring activities required during ‘peak’ times of cetacean activity: In late summer especially, Caamano Sound, and neighbouring Campania Sound and Whale Channel play host to an array of migratory and resident fin, humpback, and killer whales variously involved in annual mating, feeding, and socializing… (Ford et al, 1989, 2007). Hearing all the complex sonic activity generated by these creatures is perhaps the most pronounced feature of daily life at Cetacea Lab…

Mediterranean fin whales displaced by oil and gas noise

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Ongoing acoustic research in the Mediterranean has confirmed earlier indications that fin whales are far more affected by oil and gas exploration noise than has long been assumed. Manuel Castellote’s most recent paper details a set of disturbing findings, here summarized by the website Science Codex:

Maritime traffic and geophysical exploration –including the search for hydrocarbons– “drastically” reduces the song effectiveness –linked to reproduction and which propagates hundreds of kilometres beneath the Sea– of the whales, which are also the group of marine mammals with the greatest acoustic sensitivity at low frequencies. “The noise generated through human activity in the oceans leads to possible chronic effects on the health of this species”, Castellote states.

After analysing 20,547 hours of recordings of the sounds emitted by the whales, the study published in Biological Conservation indicated that the whales modified the characteristics of their songs in order to try to reduce the impact of noise on their propagation. In addition the researchers recorded a massive displacement of fin whales, triggered by the noise from geophysical prospecting at a distance of 285 km from the study area. “These recurrent displacements, together with the changes in acoustic behaviour, could increase the energy expenditure and reduce the reproductive success of whales affected by the noise”, the expert indicated.

In the long-term the consequences for these mammals are clear: chronic effects which impact on their survival emerge. “Noise in the marine medium, despite being recognised as a significant pollutant, is far from being controlled and regulated within the waters of the Exclusive Economic Zone of Spain”, warns Castellote

Whales can dampen hearing: implications for ocean noise concerns

Animal Communication, Bioacoustics, Effects of Noise on Wildlife, Ocean, Science Comments Off on Whales can dampen hearing: implications for ocean noise concerns

You may have noticed a recent flurry of press reports about research in Hawaii that begins to quantify a long-suspected quality of cetacean hearing: the ability to dampen hearing sensitivity so that loud sounds don’t cause damage.  Given the extremely loud volume of many whale calls, which are meant to be heard tens or hundreds of miles away, researchers have long speculated that animals may have ways of protecting their ears from calls made by themselves or nearby whales, perhaps using a muscle response to reduce their hearing sensitivity (not unlike a similar muscular dampening mechanism in humans).  Indeed, earlier studies by Paul Nachtigall’s team had found that some whales could do indeed reduce their auditory response to the sharp clicks they use for echolocation.  In the new study, Nachtigall trained a captive false killer whale named Kina to reduce her hearing sensitivity by repeatedly playing a soft trigger sound followed by a loud sound.  Eventually, she learned to prepare for the loud sound in advance by reducing her hearing sensitivity.  “It’s equivalent to plugging your ears…it’s like a volume control,” according to Nachtigall.

Well, that sounds like a pretty useful trick, given all the concern about human sounds in the sea.  And the media, led by the New York Times, jumped on board with headlines following on the Times‘ assertion that suggested whales  already “are coping with humans’ din” using this method. (Among the exciting headline variations: Whales Can Ignore Human Noise, Whales Learning to Block Out Harmful Human Noise, and UH Scientists: Whales Can Shut Their Ears.)

Oops, they did it again!  Grab some interesting new science and leap to apply a specific finding to a broad public policy question, often, as this time, giving us a false sense of security that the “experts” have solved the problem, so there’s no need to worry our little selves over it any more (as stressed in this NRDC commentary).  To be fair, the Times piece included a few cautionary comments from both scientists and environmental groups, but the headline rippled across the web as the story was picked up by others.

Two key things to keep in mind:  First, this whale was trained to implement her native ability, meant for use with her sounds or those of nearby compatriots, and to apply it to an outside sound made by humans.  This doesn’t mean that untrained whales will do the same.  

And second: If whales can dampen their hearing once a loud sound enters their soundscape, this could indeed help reduce the physiological impact of some loud human sounds, such as air guns or navy sonar. If indeed this ability translates to wild cetaceans, the best we could hope for is that it would minimize hearing damage caused by occasional and unexpected loud, close sounds that repeat.  There would be no protection from the first blast or two, but perhaps some protection from succeeding ones; or, if the sound source was gradually approaching or “ramping up,” as often done with sonar and air guns, animals may be able to “plug their ears” before sounds reach damaging levels, if for some reason they can’t move away.  Even then, the animals are very likely to experience rapidly elevated stress levels, as they would be less able to hear whatever fainter sounds they had been attending to before the intrusion. Yet research in the field suggests that most species of whales and dolphins prefer to keep some distance from such loud noise sources; this hearing-protection trick doesn’t seem to make them happy to hang around loud human sounds.  

Most crucially, these occasional loud sounds are but a small proportion of the human noises whales are trying to cope with. Noise from shipping, oil and gas production activities, offshore construction, and more distant moderate sounds of air guns all fill the ocean with sound, reducing whales’ communication range and listening area, and likely increasing stress levels because of these reductions.  This is the “din” of chronic moderate human noise in the sea, and Kina’s ability would not help her cope with any of it.  We’re a long way from being able to rest easy about our sonic impacts in the oceans.

To end this rant with a bit of credit where due, here’s what may be the more important take-away from the Times article:

Peter Madsen, a professor of marine biology at Aarhus University in Denmark, said he applauded the Hawaiian team for its “elegant study” and the promise of innovative ways of “getting at some of the noise problems.” But he cautioned against letting the discovery slow global efforts to reduce the oceanic roar, which would aid the beleaguered sea mammals more directly.

Offsore oil development expanding in remote Arctic seas

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The Anchorage Daily News ran a  great, detailed piece on the expansion of offshore oil and gas development in the Beaufort and Chukchi Seas north and west of Alaska.  It’s well worth reading in full.  The nut of the story is that Shell Oil, which has conducted seismic surveys in the northerns seas for the past few years, is gearing up to drill their first new exploratory well in over a decade.  If they find the oil they expect to, further seismic exploration and drilling is likely to follow in these remote waters, home to many species of whales.  Bowhead whales are especially sensitive to noise, especially cow-calf pairs, and have been found to give seismic surveys a wide berth.

Oil companies have been doing extensive research into the seasonal distributions of whales (especially belugas and bowheads), and have agreed to suspend operations in late August to accommodate the Alaskan natives traditional bowhead hunting season.  Meanwhile, Chris Clark, the Bioacoustics Research Program director at Cornell says, “There are unanswered science questions.  It’s not clear what happens if a whale hears 1,000 of the explosions from air guns, or where it will go if an area is saturated with the sound. In addition, scientists are only beginning to study the effects of the sound on fish and other animals that make up the whole ecosystem.”

Go read the whole article!

Floating in whalesong

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Humpback 460x230 fct372x229x52 t325

For a welcome change of pace from stories about contentious acoustic ecology issues, check out this column from Australia about a group of people who were treated to two sessions of whale song while floating near their inflatable raft. Here’s a teaser:

“This time the singer was right before my eyes, and the singing was so powerful you could actually feel it in the water. As I drifted on the surface, the sound vibrated through my body. It was an amazing experience.”

Tension builds over expanded whale “takes” in new Navy sonar EIS

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The US Navy has released its initial Draft Environmental Impact Statements for the next 5-year round of permits it will seek from the National Marine Fisheries Service for its at-sea training activities, and the numbers of animals expected to be affected have skyrocketed.  This is in part thanks to the new EISs combining areas that were dealt with separately in the first round of permitting, which occurred after the NRDC challenged the lack of permits in court.  The new Hawaii-Southern California EIS not only combines these two previous separate areas, but also accounts for impact to animals in waters between Hawaii and California that were previously not considered.  In addition, the new EISs draw on more recent scientific evidence of lower impact thresholds for some species, including beaked whales, and on more advanced models that predict animal concentrations and movements.

While this expanded focus and better data is a valuable step forward, the numbers of animals expected to be injured or to have their behavior affected has increased so much that NRDC termed it “harm of staggering proportions.”  Clearly, attempts to foster more constructive dialogue between the Navy, NMFS, and NRDC during the EIS process has not led to a shared vision or lowered the heat all that much.  The Navy’s estimate of the number of animals whose behavior could be affected has jumped from 770,000 to 14 million, including 2 million cases of temporary hearing impairment, in addition to 2000 animals experiencing permanent hearing loss.  And, the Navy estimates that explosives training and testing could kill 1000 animals. 

But, Navy officials told CNN, these alarming numbers — a result of mathematical modeling — are worst-case scenarios.  “We believe … with our mitigation efforts and the Navy commitment that those injuries and mortalities will be none,” said John Van Name, U.S. Pacific Fleet senior environmental planner in Pearl Harbor, Hawaii. The report also indicated monitoring in 2009-2010 off Hawaii and Southern California showed 162,000 marine mammals with no evidence of distress or unusual behavior during Navy activities.  By comparison, the previous round of EISs estimated injury or death to about 100 animals in Hawaii and California during the five years from 2009-13; to date, two or three dolphins are known to have been killed by explosives testing.

Zak Smith of the NRDC responds that “I am not saying they are not well-intentioned. But I am not sure their choices make them the best environmental stewards they could be.”  In a blog post, Smith elaborates:

While the Navy’s understanding of how much harm it’s activities cause marine mammals has increased, it hasn’t taken any corresponding steps to minimize this staggering level of harm.  It’s mitigation protocol remains largely unchanged, with the Navy refusing to set aside areas of high marine mammal density where sonar should not be used.  This means sensitive breeding and foraging habitats and biologically unique areas within the training area can still be used for sonar and underwater explosives training. We know that safeguarding specific areas of sensitive habitat is the best way to lessen harm to whales and dolphins from sonar and other activities — don’t use the technology in the same areas where whale and dolphin numbers are high or during breeding seasons.  Faced with such incredible numbers and levels of harm, the Navy must do more to identify and set aside portions of its training areas (areas often the size of large states, like California) where it will not conduct training and testing.

For more on the EIS process, see the Navy’s information sites for the Hawaii-Southern California EIS and the Atlantic Fleet EIS.  Comments on both are being accepted through July 10.

Cook Inlet seismic survey permits challenged in court

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Permits issued by National Marine Fisheries Service to allow seismic surveys in Alaska’s Cook Inlet have been challenged in Federal Court.  Cook Inlet is home to a dwindling population of beluga whales (under 300), and the permits allow behavioral harassment of up to 30 belugas per year. In part, the challenge contends that this likely underestimates the impact, as, “NMFS based its analysis on an unrevised, outdated, 15-year-old assumption about take levels that some of the world’s leading bioacousticians recently urged NMFS to discard – and that ignores the only existing study of airguns and belugas, showing impacts at far greater distances than NMFS has predicted here.” Saying that the Marine Mammal Commission recommended against issuing the permits, the suit claims that NMFS erred in its finding of “no significant impact.”

BelugaIn addition to three environmental organizations, the Native Village of Chickaloon is party to the lawsuit, saying that NMFS did not fulfill necessary consultation with the tribe, and noting that while the tribe is barred from its traditional hunts due to declining beluga numbers, the permits allow oil and gas development to put whales at risk.

The suit claims that an Environmental Impact Statement should have been prepared, rather than a less comprehensive Environmental Assessment.  As covered in previous AEInews posts over the past four years, NMFS has declared parts of Cook Inlet to be essential habitat for the belugas, though the 180-mile long inlet continues to bear the brunt of substantial industrial activity, including the Port of Anchorage and ongoing oil and gas development.

Tubular wind turbine foundation much quieter to install offshore

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As countries around the world gear up to expand offshore wind development, one of the major concerns of ocean biologists is the exceedingly loud noise of pile driving during construction. Studies suggest that some ocean species move at least 20km from turbine construction areas, and in areas with lots of planned construction (such as the North Sea), it’s possible that large swatches of shoreline could be impacted each summer for many years.

PREONmarine 2

A new mounting system from the French firm Vallourec uses a series of thin tubes to anchor three octagonal “feet”; these are inserted in to holes drilled only 20m into the seabed, rather than the 60m that piles are driven into the seabed, supporting the huge concrete foundations used in today’s standard construction technique.  Vallourec claims that construction noise is limited to about 75dB, as compared to pile-driving’s 200dB (though I suspect they’ve neglected to correct the 75dB for measurement in water; even the resulting 138dB would be a moderate noise by comparison to pile driving).  The initial press release and website does not give a ready sense of how the cost of the new “PREON Marine” system compares to traditional pile-driving and foundations.

 

Japan commits to floating offshore wind

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In order to compensate for the abandonment of many nuclear plants, the Japanese government has set its sights on the abundant wind resources off its coast.  A 15MW pilot floating wind turbine project is under construction not far from Fukushima; if all goes well, the project could expand to as large as 1000MW.  Along with smaller pilot projects in Norway and Maine, the Japanese effort will be a key player in moving floating offshore wind forward.

Currently, capital expenditure is about $1.7 million a megawatt for an onshore wind project and $5.5 million a megawatt for offshore, according to Bloomberg New Energy Finance; floating offshore designs are still under development, raising initial costs even higher.  Over time, though, the cost is expected to come down enough to support widespread deep water floating wind farms; a feed-in tariff program promoting clean energy allows projects to receive higher-than-market rates as the sector develops.  Floating turbine designs are larger than onshore turbines, and can take advantage of stronger, steadier winds; foundation systems for floating turbines are much smaller than bottom-mounted near-shore foundations, minimizing impacts on the seabed and reducing the noise impact of construction.

US east coast seismic survey EIS draft released

Effects of Noise on Wildlife, News, Ocean, Seismic Surveys 1 Comment »

The US Bureau of Ocean Energy and Management (BOEM) has released the Draft Programmatic Environmental Impact Statement that is the first step toward oil and gas development off the east coast.  The PEIS assesses the impacts of geological and geophysical (G&G) activities, primarily seismic surveys and test wells.

OCS seismicI’ve yet to dig into the PEIS to examine its alternatives or proposed mitigation measures, but a quick look at maps illustrating applications already received from oil and gas exploration companies affirms that the entire east coast could become an active seismic survey zone (the map at left is one of nine applications; there is much overlap among them).

UPDATE, 3/30/12: While those maps look impressive, both the International Association of Geophysical Contractors and the American Petroleum Institute have issued statements that surveys are unlikely to take place until the path opens for actual leases to be issued; the decision was already made to not issue any Atlantic leases during the current 2012-2017 planning period.  The applications for surveys currently on file were submitted during a period in 2008 when a long-standing Presidential order excluding oil and gas development on the Atlantic coast was lifted. “Without an Atlantic coast lease sale in their five-year plan, theadministration’s wishful thinking on seismic research has no ultimate purpose,” said Erik Milito, upstream director at API. Chip Gill, IAGC President, stressed that “contrary to the statements [by US Interior Sec. Ken Salazar and BOEM Director Tommy P. Beaudreau], we do not expect seismic surveys to be conducted for years, and thus we don’t expect it to be available to help the federal government evaluate the resource base anytime soon.”

(and now back to our original post):
While very few animals are killed or injured by air gun sounds, behavior can be affected for tens of miles, and airgun sound can be heard (and so drown out some distant communication) for hundreds of miles.  I just returned from a BOEM workshop on the effects of ocean noise on fishes and invertebrates, where scientists shared research on reduced fish catch rates near surveys (the fish move away for a few days or weeks, then gradually return), and attempted to come up with a shared understanding of how to investigate whether ocean noise can affect fish communication, larval or egg development, or other aspects of ocean ecology (so far, there is little direct evidence of impacts, but some concern remains about masking of sounds fish use for many purposes, and the possible negative stress impacts of chronic noise exposure).

From looking at the maps of existing applications to do surveys (download pdf of rough maps of all 9 applications), it’s immediately apparent that BOEM could work to minimize duplicating of efforts by several companies.  It may be that there will be areas that are clearly inappropriate for oil and gas development (eg, key fishing grounds or other biologically important areas), or seasonal exclusions to reduce impacts on spawning or migration.

Of course, there’s also the bigger-picture climate change question of whether we really want to be continuing to pull more oil and gas from the ocean in the years after 2020 anyway; any new leases will be issued after 2017, with development following years later.  Meanwhile, BOEM is working hard to lay the groundwork for renewable energy development in offshore waters, targeting areas for wind, tidal, and wave energy systems.  For now, continuing to plan for oil and gas development is part of the Obama administration’s “all of the above” approach to meeting America’s future energy needs.

For more on the Draft PEIS, see BOEM’s PEIS website, which includes links to download the documents and submit comments, this press release from the Department of the Interior, and this blog post from NRDC (which stresses that quieter alternative technologies for oil and gas exploration are expected to be commercially available in 3-5 years).

AEI invited to shape renewables conference agenda, NOAA ocean noise mapping effort

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My dance card is filling up for the spring!  AEI’s years of working hard to play a constructive role in public and professional dialogue about policy responses to noise-related environmental issues has been rewarded with two invitations that I’m very excited about.

The first was an invite to server on the Wind subcommittee of the program committee for this year’s Renewable Energy World North America conference.  The big event takes place in December, but this week the program committee began its work with a conference call, and during April we’ll be assessing presentation proposals and coming together to meet for two days in Orlando.  I’m honored and pleased that the good folks at Renewable Energy World, the premier trade magazine for all renewables, thought that my input would be valuable.

Chronic Noise NE US oceanI’ve also been invited to participate in a small, invitation-only symposium being convened by NOAA (National Oceanic and Atmospheric Administration) and BOEM (Bureau of Ocean Energy and Management) to gather feedback on NOAA’s recent efforts to engage in ocean sound and cetacean distribution mapping, and to discuss ideas about how to use and develop these new tools to inform future ocean management decisions.  As a long-time advocate of more concerted mapping of current human sound in the oceans, I’m especially excited to participate in this event. We’ll gather in DC for two days in late May.  I got the good news on this invitation earlier this week while attending a BOEM workshop on the effects of noise on fish and invertebrates; I hope to post a brief summary of the proceedings later this week.

 

Ocean noise assessment needs to look past dB, to context of exposure

Bioacoustics, Effects of Noise on Wildlife, Ocean, Science, Seismic Surveys, Shipping, Sonar Comments Off on Ocean noise assessment needs to look past dB, to context of exposure

A paper recently published in Conservation Biology suggests that current ocean noise regulations are likely not providing sufficient protections against impacts on marine life.  The authors note that current regulations are based on preventing direct physical injury from very close exposure to sound, while considering behavioral impacts to decrease consistently with greater distance, or the “zones of influence” approach to noise impact assessment.  However, some key impacts, such as interruptions in feeding or temporary abandonment of important habitat, are not accounted for.

Rather than fully summarizing the paper here, I’ll turn you over once again to Caitlin Kight of Anthropysis, who has recently been providing excellent coverage of anthropogenic noise issues as part of her larger focus on human impacts in the natural world.  Please see her full post to get the whole story; here’s a teaser:

In a previous study on behavioral responses of marine animals to noise, one of the authors of the current paper found that the “zones-of-influence approach did not reliably predict animal responses.” Furthermore, we know from terrestrial studies that a variety of additional factors–an animal’s past experience and conditioning, current behavioral state, acoustic environment, and type of exposure, to name a few–all affect the extent to which it will be impacted by noise pollution.

…(Studies in terrestrial and ocean environments have shown that) noise can have more subtle, but equally important, effects on wildlife. For instance, abundance and diversity may shift as animals flee from, or learn to avoid, particularly noisy areas; individuals may alter their behaviors in counterproductive or even dangerous ways; and noise may make important acoustic signals difficult to hear, even in the absence of actual deafness. In short, the researchers write, the current marine noise concept “ignores a diverse suite of environmental, biological, and operation factors” that can impact both perception of, and response to, anthropogenic noise. Thus, they argue, it is necessary to overhaul the system and “[incorporate] context into behavioral-response assessment.”

Ellison, W.T., Southall, B.L., Clark, C.W., and Frankel, A.S. 2012. A new context-based approach to assess marine mammal behavioral responses to anthropogenic sounds. Conservation Biology, online advance publication.

Canadian sonar heard in US critical orca habitat

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HMCS OTTAWA 300x207A Canadian frigate used its mid-frequency active sonar this week during a training exercise in Haro Strait, north of San Juan Island and south of Vancouver Island.  The sonar emissions from the HMCS Ottowa (right) were picked up by whale researchers at Beam Institute, who raised concerns about sonar use in an area designated by the US as critical habitat for orcas. You can read a detailed report from Beam, including sonograms and MP3 files of the sounds heard, at their website. They note that “the peak power frequency is consistent with the 2-8 kHz frequency range specified for the SQS 510 sonar system, which is manufactured by General Dynamics Canada. Each ping had high intensity receive levels for ~0.5 second duration and pings were separated by about one minute.”

According to the Seattle Times:

The frigate was in Canadian waters at the time, said Lt. Diane Larose of the Canadian navy.  But the Ottawa’s sonar can travel 4,000 yards — more than two miles — and the sound was picked up by instruments in U.S. waters. Larose said the Canadians are well aware of sonar’s potential to hurt killer whales, which communicate by sound at similar frequencies. In 2008, the Canadian Navy adopted a policy requiring the use of radar, passive acoustic systems, underwater listening devices and night-vision goggles to make sure marine mammals aren’t present when sonar is deployed. “We take this very seriously,” Larose said. “It’s a very well-thought-out policy.”

Scott Veirs of Beam Research said that their monitoring network had tracked both transient orcas and endangered southern resident orcas in the area within 24 hours both before and after the incident. “This was a fairly high-risk event as far as we can tell…it’s concerning to me that the U.S. Navy has voluntarily refrained from unnecessary testing and training in the inland waters of Washington state, but the Canadian navy apparently still does,” he said. “The nightmare scenario is that you turn on sonar not knowing they are there and essentially deafen them either temporarily or permanently.”  Ed. note: Beyond this worst-case scenario, the use of this high-intensity sonar in waters close to designated critical habitat goes against the purposes of designating such protected zones; the US has banned all boat activity in some parts of the habitat, with the goal of assuring that the whales are not discouraged from using this region, one of their primary feeding grounds.

Interestingly, a commenter on the Beam Reach website notes that the Canadian Navy’s safety zone for their mid-frequency active sonar is 4000 yards, or over two miles.  Whether they can effectively detect whales at that distance, especially at night, is highly questionable. The Seattle Times clip above mistakenly presumes that the sounds travel only that far. In fact, this is just where they tend to drop below the sound levels considered likely to seriously disrupt behavior; mid-frequency active sonar can be heard for tens of miles, and in the complex underwater landscape of where this event took place, is likely to create dramatic peaks and drops in sound levels as the noise bounces from islands and the seabed, making it difficult for animals to know how to reduce their exposures.

Serendipitous study: whales relaxed in shipping lull after 9/11

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Ship and whaleA fascinating new study provides the first direct evidence that shipping noise may increase stress levels in whales.  During the days after the World Trade Center attacks, global shipping was halted; a team of researchers studying right whales in the Bay of Fundy decided to go ahead and continue collecting fecal samples, and were struck by how peaceful it was: Rosalind Rolland recalls that day and those following were like a primal ocean scene, “There was nobody out there except for us and the whales.”

In 2009, Rolland realized that another researcher, Susan Parks, had recordings of noise levels for the days before and after 9/11, and so they joined forces to see whether the samples taken from whales on those days showed any changes in stress levels (fecal matter contains stress hormones that can be measured).  As it turns out, the days after 9/11 mark the only time during Rolland’s five-year study that stress hormone levels were markedly lower than the overall average, and corresponded to a dramatic reduction in noise, especially low-frequency noise.

““This is what many of us had been looking for,” said Christopher Clark, director of the bioacoustics research program at the Cornell Lab of Ornithology, who was not a paper co-author. “Here is the first solid piece of evidence that says there’s a link between noise level and stress.” Clark noted stress has long been tied to longevity, reproduction, disease and other key health indicators in whales. Researchers have long speculated that noise could be a stressor for ocean creatures, but there is no practical way to test a correlation, since ocean noise is nearly omnipresent in most areas.

The fact that this is an opportunistic study does mean that it’s unlikely to be considered solid proof, or to influence ocean noise policy.   As Dr. Rolland noted, “These are after all 50 tonne animals so they don’t make terribly easy things to study…Past studies have shown they alter their vocalisation pattern in a noisy environment just like we would in a cocktail party, but this is the first time the stress has been documented physiologically.”

Dr. Ian Boyd of the University of St. Andrews in Scotland, home to many top ocean noise researchers expressed uncertainty that such a short time period and small sample “shows what is claimed.”  Boyd is one of a group of researchers advocating for a Quiet Ocean Experiment, in which large portions of ocean would be quieted for brief periods, allowing for more comprehensive studies of animal behavior and physiology before, during, and after the experimental periods.  To implement this idea, global shipping routes would need to be shifted for the duration of the experiment.

NRDC re-opens legal battle with Navy, NOAA over sonar

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Three years after the NRDC and U.S. Navy reached an agreement that was meant to create avenues for dialogue and collaboration, a new lawsuit filed this week suggests that the hopes both sides held have not been realized. The main sticking point remains the same now as it was then: environmental advocates insist that some biologically rich areas should be entirely off limits to any sonar training activity, while the Navy holds that short-term exercises pose no great risk to wildlife. The final Environmental Impact Statements submitted by the Navy, and the permits issued by the NOAA Fisheries Service (which collaborates closely with the Navy in developing guidelines), allow the Navy full access to extensive training ranges that stretch along most of the coastlines of United States. The suit filed this week challenges NOAA permits issued in 2010 for one of the Navy’s dozen or training ranges, off the coast of Washington, Oregon, and northern California. It differs from an earlier high-profile legal challenge, which reached the Supreme Court, in that the previous suit challenged the Navy’s sonar operational guidelines, whereas this one challenges NOAA’s permits.

Navy ranges WEB

The Navy is already beginning work on Environmental Impact Statements that will accompany new permit request for all of its ranges, each of which must receive fresh authorization from NOAA every five years. The Navy has recently completed its first-ever EIS’s for training ranges around the world (a process spurred largely by earlier legal challenges); these 5-year permits were issued for some ranges in 2009, and are due for renewal in 2014 and beyond.  The operating conditions proposed by the Navy and approved by NOAA for the first-round EISs and permits are generally similar to the way the Navy had been doing things for many years. Marine mammal monitoring is maintained on sonar vessels, with sonar intensity reduced when whales are seen nearby, and operations stopped when whales approach very close to boats. The litigants point out that visual monitoring misses 25-95% of whales, and is particularly ineffective in high seas. “We learn more every day about where whales and other mammals are most likely to be found,” said Heather Trim, director of policy for People for Puget Sound, “We want NMFS to put that knowledge to use to ensure that the Navy’s training avoids those areas when marine mammals are most likely there.”

By and large, ocean noise regulations concern themselves only with noise that may be loud enough to cause injury, which occurs only at very close range (under a half mile). More moderate noise, which may cause behavioral changes up to 50 miles away, is assessed in the EIS, but these behavioral changes are generally considered to be of negligible impact to the animals. Recent NOAA permits routinely allow for tens or hundreds of thousands of animals to respond in some way to the sounds of naval maneuvers, with sonars mounted on ships, on floating buoys, and dangled from helicopters being the primary noise source triggering behavioral responses (any behavioral response is considered a “take” in permitting language).

The Navy says that in the Northwest Training Range Complex sonar training exercises typically

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UK researchers examine effects of noise on fish, crustaceans

Effects of Noise on Wildlife, Ocean, Ocean energy, Science 2 Comments »

A research project in England is preparing to do some of the first field studies designed to see how human-made sound may affect non-cetaceans.  While many field studies have tracked the responses of whales and dolphins in both opportunistic and controlled settings, and some lab studies have noted how fish or other sea creatures react to noise when introduced into tanks, a team from the University of Hull is preparing to project human sounds from a research vessel and see how fish and crustaceans (crabs and lobsters) respond.

The researchers plan to film animals while playing the sounds of ships, concrete pile driving, or operating wind turbines; the results will provide data for far more accurate environmental impact assessments of offshore construction and renewable energy projects.

For more, see this recent article from OffshoreWind.

Leading scientists call for reducing ocean noise

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NOAA humpback with calf copyTwo of the US’s most widely-respected ocean bioacousticians have called for a concerted research and public policy initiative to reduce ocean noise.  Christopher Clark, senior scientist and director of Cornell’s Bioacoustics Research Program, and Brandon Southall, former director of NOAA’s Ocean Acoustics Program, recently published an opinion piece on CNN that is well worth reading in full.  They stress the emerging scientific awareness that chronic moderate noise from shipping and oil and gas exploration is a more widespread threat to marine life than the rare injuries caused by loud sound sources like sonar.  Here are a couple of teasers:

Today, in much of the Northern Hemisphere, commercial shipping clouds the marine acoustic environment with fog banks of noise, and the near continuous pounding of seismic airguns in search of fossil fuels beneath the seafloor thunder throughout the waters. In the ocean’s very quietest moments, blue whales singing off the Grand Banks of Canada can sometimes be heard more than 1,500 miles away off the coast of Puerto Rico. But on most days, that distance is a mere 50 to 100 miles.

Whales, dolphins and seals use sounds to communicate, navigate, find food and detect predators. The rising level of cumulative noise from energy exploration, offshore development and commercial shipping is a constant disruption on their social networks. For life in today’s ocean, the basic activities that we depend on for our lives on land are being eroded by the increasing amount of human noise beneath the waves.

These stark realities are worrying. But emerging technologies for quantifying and visualizing the effects of noise pollution can help drive a paradigm shift in how we perceive, monitor, manage and mitigate human sounds in the ocean. Ocean noise is a global problem, but the U.S. should step up and lead the way.

Clark and Southall make three specific recommendations: to establish a more comprehensive network of acoustic monitoring stations in order to better understand our overall acoustic footprint in the seas; to encourage and accelerate development of noise-reduction technologies (especially to make ships quieter, and also to develop new technologies for oil and gas exploration and underwater construction that generate less noise); and a shift in federal regulations from avoiding acute injury, toward protecting ocean acoustic habitats and ecosystems.

Ocean listening stations go online; US Navy aims to filter out its activities

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A growing network of ocean observatories are adding hydrophones to their arrays of instruments, opening ears into the undersea world.  The data has been shared widely among scientists for the past few years, and a website, Listening to the Deep Ocean Environment, is now compiling the real-time acoustic streams from 15 of the observatories, allowing anyone to listen in; another 11 observatories will be added in the coming months.  This excites scientists and citizens alike. (Though truth to tell, most of the audio streams aren’t all that interesting to listen to most of the time!)

The US Navy isn’t quite so pleased, however. According to a recent BBC article, US Navy oceanographers have arranged to filter data from one of the largest ocean observatories, NEPTUNE, off the coast of British Columbia.  Citing concerns that the recordings will disclose areas of Navy operations, real-time recordings are cleansed of Navy ship (and presumably sonar) sounds, then returned to NEPTUNE operators for uploading to the web. 

Cornell University’s Chris Clark doubts that the Navy’s approach will catch on at other observatories around the world.  According to a piece on The World, from PRI and the BBC, (sounds above from there; roll over tiny screens to ID the sounds), Clark says the US Navy doesn’t own the ocean acoustic environment and has to accept that what was once military technology is now in the hands of civilians.  “The cat’s out of the bag, the horses are out of the barn, whatever the metaphor is, it’s happening,” he says.  The piece notes that this is similar to what happened with satellite imagery. For decades, it too was sensitive military data, but now anyone can go on Google Earth and look down from space.

Fish survey sounds reduce humpback songs 120 miles away?

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AEI lay summary of the following paper:
Risch D, Corkeron PJ, Ellison WT, Van Parijs SM (2012) Changes in Humpback Whale Song Occurrence in Response to an Acoustic Source 200 km Away. PLoS ONE 7(1): e29741. doi:10.1371/journal.pone.0029741
Read or download online (free)

An ongoing research project that monitors whale calls and shipping noise in Stellwagen Bank east of Boston Harbor has reported an unexpected reduction in humpback whale songs during an 11-day period in which their recorders picked up low frequency sounds from a fish-monitoring system 120 miles away.  If this data does indeed represent whales ceasing singing or moving away in response to the distant sonar, this would be the first clear-cut indication that discrete human noise events may affect marine mammal behavior outside the immediate area.  The authors note that these results could suggest that impact assessments need to consider effects at longer ranges, and that effects may occur at received sound levels much lower than those generally considered worthy of concern.  This study simply reports the reduction in singing; any longer-term effect that may have on the animals is unknown (these are not mating calls).

The reduction in songs occurred at a time of year (early fall) when humpback songs are beginning to increase in this area; on years when the fish sonar was not in operation, the numbers of songs steadily increased over the 33-day study period.  But in 2006, when the fish sonar was heard at Stellwagen Bank for 11 days (8 of which included sonar sounds for over 7 hours), the number of minutes per day when humpbacks were singing dropped, some days to zero.  The average (mean) number of hours of whale song dropped from about 75 in the previous 11 days to about 15 minutes during the time the fish sonar was heard, before increasing to close to 3 hours per day once the sonar transmissions ceased.

The figure below shows the data from each of three years.  For each year, there are 33 days of data, with the middle 11 days being the period (Sept. 26-Oct 6) in which the sonar sound occurred in 2006.  The open circles are the mean minutes/day for each 11-day period, with the rectangular boxes representing the upper and lower quartiles of data for each period; black dots represent one or two days in each period in which the calling rates for that day were unusually far outside the range for other days in that period.

Risch 2012 dataWEB

Ed. note: Interpreting the results of vocalization studies is complicated by the fact that there is much variability in vocalizing rates, and response/sensitivity to human noise, from one animal to another; and similarly, in numbers of whales in the area from year to year.  (This acoustic data counts singing minutes, but not animal numbers, which must be monitored visually.)

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