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Leading scientists call for reducing ocean noise

Bioacoustics, News, Ocean, Science, Seismic Surveys, Shipping, Sonar Comments Off on Leading scientists call for reducing ocean noise

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.

New tech may reduce harmful noise of sonar, airguns

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Several new R&D projects are underway by providers of ocean technology, each of which either aims to reduce the harmful behavioral impacts on marine creatures, or may limit harmful impacts as a byproduct of their innovations.

My good friend Michael Stocker already wrote up a solid blog post  that summarizes three such projects, with links to source material and more information. Head on over to his Ocean Conservation Research blog to hear more about sonar signals modeled on sperm whale clicks (likely to be far less distressing for whales and dolphins that today’s grating signals), continuous low frequency sonar (which could reduce the source level), and airguns with less stray noise outside of the frequencies used to probe the seabottom.

Mass whale stranding during Italian Navy exercises: sonar heard?

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Over the past week, a mass stranding of Cuvier’s beaked whales has taken place along the shoreline of Corfu (a Greek island) and southern Italy. The first whales came ashore on November 30, halfway through an Italian Navy exercise taking place in waters on both sides of Italy, including the 130-mile wide Ionian Sea, which separates the two stranding sites. At least one of the Italian ships is known to be equipped with mid-frequency active sonar.

While it’s become common media sport to mention sonar in conjunction with any whale strandings, to the point that once I read the coverage, I rarely see any real evidence, this case is different.  Most strikingly, rescuers in two separate locations during the initial strandings report hearing a “whistling” noise at 10-15 second intervals; it’s quite likely that this sound was what drove the animals ashore. While rare, this is not the first time that humans above the water have heard underwater sound transmissions during stranding events.


On November 30, three or four Cuvier’s beaked whales stranded on Corfu, while two (a female and calf) came ashore across the Ionian Sea in italy. Some were helped back to sea by bystanders, and some died; two of the Corfu whales were collected and necropsies were done, with one being fresh enough for detailed observations.  On December 6 and 7, a total of four more Cuvier’s washed ashore in the same area of Corfu; these were all dead, and decomposed to the point that researchers believe they died at about the same time as the initial strandings took place. According to Alexandros Frantzis, a longtime beaked whale researcher, “It is reasonable to think that there are more animals in the pelagic waters of the Ionian Sea, which may never reach the coasts. The local and apparently small Ionian population unit has suffered three stranding events coinciding in time and space with use of military sonar in the past (plus one in east Sicily earlier this year). There should be little doubt (if any) that the cumulative damage at the population level is high.”

Marine mammal scientists in the region share Frantzis’ alarm about the vulnerability of this population of beaked whales. Both Guiseppe Notarbartolo di Sciara and Natacha Aguilar de Soto have sent urgent letters to officials at ACCOBAMS, a multinational binding agreement between most European and several North African and Middle Eastern countries aimed at coordinating cetacean conservation efforts in the Mediterranean and Black Seas. They ask ACCOBAMS to take the lead in investigating the circumstances of this stranding event, and stress the need to avoid further such incidents in this highly vulnerable population. di Sciara, a former chair of the ACCOBAMS Scientific Committee, notes agreements already made, and asks what steps have been taken to assure compliance and follow-through. In her letter, Aguilar de Soto notes that in the Canary Islands, after several such strandings, active sonar use was banned within 50 miles of the islands, and no further strandings have taken place; she note that similar policies may be necessary “in known important areas of distribution of beaked whales in the Mediterranean, to guarantee the sustainability of the populations.”

You can read the letters of Drs. di Sciara and Aguilar de Soto after the break.

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2nd year of behavioral response study underway off California

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For the second of a planned five summers, a team of researchers is spending a couple weeks in waters off southern California, attaching suction-cup acoustic tags to whales, then playing sounds underwater to see how they respond to different sounds and intensities. Another two weeks of field work will occur in late September. As Brandon Southall notes on his SEAblog, which provides excellent coverage of the trip, the team is “interested in testing the differences in responses of marine mammals in the various kinds of habitats in which they live and are exposed to human sounds.” After several years of study, the research is moving beyond simply getting one or two examples of any given species, toward the development of a wide array of examples of each species, in different circumstances (at least for the easier-to-tag species). The study is known as a Behavioral Response Study (BRS), which used to be called Controlled Exposure Experiments (CEE), with the CEE term still in use as the name of each individual playback to a tagged animal. This year’s southern California version goes by the name of SOCAL-11. The acoustic tags used in the study allow researchers to record the actual sounds heard by the animals (including of course their own foraging and communication vocalizations), while also tracking their swimming speed and dive patterns.

It’s always easier to find and approach the large whales, such as blue and fin whales, so the team tends to focus on these species when waves are higher; in light seas, they are largely seeking the harder-to-locate, and much harder to approach beaked whales, as well as Risso’s dolphins. Here’s a taste of what you’ll find if you follow the study on the SEAblog (the picture above is the animal he’s so enthused about):

Rissos dolphins are among our focal species for SOCAL-11 experiments.  We conducted one CEE on this species last year in SOCAL-10 and have been hoping for more this year.  This species has also proven somewhat difficult to tag in the past and our tags on last year were for just a few hours, so to get a nine hour deployment spanning several different behavioral modes was pretty exciting.  The tag came off late into the evening, but quite close to our anchorage and we made a beautiful late night ride in very calm seas and a red-yellow moon out to safely retrieve it.

In addition to increasing the data set of carefully measured behavioral responses to sound, the researchers are testing two leading-edge technologies: a next-generation acoustic tag, and a towed hydrophone system deployed from a sailboat that’s being used to try to find animals for possible tagging by hearing them from afar.  Plus, associated research is underway, including a study of the prey and oceanographic conditions around tagged animals, which aims to learn something about how the ocean conditions relate to where the prey is, and thus where the whales are, as well as to see whether behavior in response to sound is different when prey is present or not.

You can learn more about the SOCAL BRS study, including powerpoints describing last year’s findings, at the SOCAL-BRS web page.  Or, get more current updates by following the study on the SEAblog, or on the SOCAL-11 Facebook page (which includes some videos):!/pages/Behavioral-Response-Studies-of-Marine-Mammals/153316228012219



More detailed confirmation that beaked whales move away from sonar exercises

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This post is an AEI lay summary of the following paper:

McCarthy, Moretti, Thomas, DiMarzio, Morrisey, Jarvis, Ward, Izzi, Dilley.  Changes in spatial and temporal distribution and vocal behavior of Blainville’s beaked whales (Mesoplodon densirostris) during multiship exercises with mid-frequency sonar.  Marine Mammal Science, Volume 27, Issue 3, July 2011.

For the past several years, ongoing research at the US Navy’s AUTEC training range in the Bahamas has been providing data that confirms what many had long suspected: that beaked whales move away from active sonar transmissions.  A recent paper published in Marine Mammal Science quantifies the changes in more detail than has occurred before.

Using recordings from the permanently-installed hydrophones lining the seafloor of AUTEC, the researchers charted the foraging vocalizations of Blainville’s beaked whales before, during, and after extended Naval training exercises (85 hours in 2007, 65 hours in 2008). In 2007, when activity was high prior to the exercises, animals returned to the range in somewhat lower numbers within 24 hours:

AUTEC 2007

in 2008, when there was less activity prior to the exercises, very few animals returned in the first three days, but many were there shortly thereafter:

AUTEC 2008

Among animals who continued foraging while sonars were nearby, they appeared to tolerate received levels ranging from 101 to 157db, which correlate to sonar transmisisons from ships 2-28km away.  A key question considered is whether the animals left the area, ceased vocalizing, or were masked by the exercise sounds. Because of the way that vocalizations increased first around the edges of the range, moving toward the center, the researchers are confident that the animals predominantly left the range; the decreased levels of vocalizations even around the edges imply that most animals moved more than 6km from the range (the limit of confidently knowing they’ll be heard by hydrophones along the perimeter).

The paper concludes by summarizing related ongoing research, including studies that aim to determine whether decreased foraging, especially directly after exercises, is due to fewer beaked whales in the area, or less preay (ie, was the prey moved off the range by the exercise activity and noise?).  The authors also note many as-yet unanswered questions that are triggered by their results, including whether the displaced animals continue feeding elsewhere during their absence from the range, and whether this particular population is more habituated to the sonar sounds, so that they either tolerate it better or are less apt to exhibit the presumably more dangerous behavioral responses that lead to strandings.

Key step toward identifying key beaked whale habitat, avoiding sonar exposure?

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A study just published is a tentative first step toward knowing where beaked whales may be foraging, and so perhaps avoiding exposing them to mid-frequency active sonar without having to see or hear them first.

The study, briefly described in this press release, found that beaked whales were more numerous in an area of their known habitat where salinity and temperature conditions increased the abundance of their prey.  Yup, that’s right:: they found that beaked whales congregate in areas where there are more fish they like to eat!!  Ain’t science great?

Seriously, though, such studies are important to ocean planners, as they provide the necessary causal data that can later (once the results are replicated elsewhere) be used to craft operational measures meant to protect beaked whales from harm.  These whales, which surface for only a few minutes at a time between 90-minute foraging dives, are notoriously hard to see, and not much easier to listen for, making it difficult to be sure whether they are nearby before a Navy ship begins sonar exercises.  The Navy has been reluctant to set aside potential habitat as “no-go” zones for their training, since even in possible habitat, there is no way to really know that animals are present.  Studies such as this one are small steps along the way toward getting solid enough data to know, more specifically, where whales may be more likely to congregate. Previous studies on harbor porpoises and bottlenose dolphins have shown how modeling habitat can be a powerful tool to inform spatially adaptive management of ocean predators.

Beaked whales avoid sonar at low sound levels

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The latest in a series of studies looking at responses of beaked whales to Naval mid-frequency active sonar has provided some new details that reinforce our understanding that this family of deep-diving whales is extremely sensitive to noise intrusions.  The study, which took place on a US Navy training range in the Bahamas which is outfitted with seafloor recorders, found that beaked whales react to sonar signals below 142dB, and that they move an average of 16km away as soon as sonar operations begin, not returning until 2 to 3 days later.

It’s long been known that beaked whales tend to leave the range when exercises are taking place, but this study was the first time that some whales were tagged, to track exactly how far they went and how long they stayed away.

“Results… indicate that the animals prematurely stop vocalisations during a deep foraging dive when exposed to sonar. They then ascend slowly and move away from the source, but they do resume foraging dives once they are farther away,” said David Moretti, Principal Investigator for the US Navy.

“It was clear that these whales moved quickly out of the way of the [navy] sonars. We now think that, in some unusual circumstances, they are just unable to get out of the way and this ends up with the animals stranding and dying,” said Professor Ian Boyd, chief scientist on the research project. However, Boyd added “There is a tendency to blame the Navy for every stranding event and that is ridiculous.”

“Perhaps the most significant result from our experiments is the extreme sensitivity of these animals to disturbance,” said Boyd. “I am also worried that the general levels of sound that humans make in the ocean from all sorts of sources like ships, oil and gas exploration and renewable energy may be a much more serious problem for beaked whales and some other sensitive species.”

See good coverage from BBC and the Daily Mail, and read or download the research paper at PloS ONE.

Navy looks to “Continuous Active Sonar” for anti-sub protection, less impact on whales

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While it looks like it’s been on the drawing board since at least 2004, today I ran across a news report on what appears to be an increasingly well-defined plan to outfit surface ships with a new Continuous Active Sonar (CAS) system.  In the face of what is perceived as an increasing threat from quiet subs, along with the increasing costs of compliance with environmental regulations that now govern current sonar systems (primarily the mid-frequency active sonar deployed on hundreds of ships, along with gradually increasing use of low-frequency active sonar on two US and a few UK ships), research and development efforts are turning toward the possibility of using a continuous, lower power sonar system to protect Naval vessels.

The sinking of a South Korean vessel, along with the embarrassing appearance of a Chinese sub that surfaced, undetected, within firing range of a US aircraft carrier group in 2006, has highlighted the gaps in detection that are inevitable using a sonar surveillance system that is only activated at times.  While none of the news or technical pages that I found specified the projected source level or frequency range of the new CAS system, one of its benefits was repeatedly claimed to be that it would broadcast at a lower power level, thus reducing impacts on marine species.  It sounds like they would trade the drawbacks of high sound levels for the different but not insignificant effects of adding more continuous background noise to the ocean environment.  One of the rarely-noted factors that may well contribute to the behavioral responses seen in reaction to the the current generation of mid-frequency active sonar is the chaotic, and quite disturbing, nature of the sound source; this is sometimes referred to as the kurtosis of the sound (how many sharp or abrupt elements there are in the sound itself, including sudden rise times rather than more rounded sine-like changes in intensity that are heard in most naturally-produced sounds).  If there is to be a new generation of continuously-broadcasting sonars, let us hope that the sounds themselves are more closely modeled on naturally-occuring sound patterns.

For more on the Continuous Active Sonar system, see:
The recent news report, about research at Alion Science and Technology in Mystic, CT
These two pages from Signal Systems Corporation, also researching the system
A recent Congressional earmark for research
This 2006 news report on a Signal Systems contract that mentions CAS
A September 2009 Navy powerpoint presentation on advanced development plans for undersea systems, which includes a slide on CAS

Ocean Conservation Research has been studying the implications of kurtosis and rise times to ocean noise sources, especially sonar.  For more, see this research page, and especially these two papers and this audio-video demonstration.

Navy jumps on sonar EIS merry-go-round, aiming at 2014 renewals

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As many of you know, over the past two years, the Navy has completed its first-ever Environmental Impact Statements for mid-frequency active sonar, in concert with applying for permits to allow them to do sonar training missions in Naval training ranges off most of the coastlines of the US.  This training activity has been ongoing for decades, but after the infamous stranding event at a Bahama range in 2000, and legal pressure applied by NRDC and others, in the mid-2000’s the Navy initiated the process of complying with NEPA provisions that govern activities that may have harmful consequences for wildlife (an internal memo shortly after the Bahamas incident suggested the need to comply with NEPA, but formal compliance activities did not begin until after a 2004 lawsuit).

During 2009 and 2010, the Navy has filed its final EIS’s on most of its ranges, but the environmental compliance treadmill never really ceases, because their authorizations must be renewed every five years: this week, work began on the next round of EIS’s, aiming for 2014 deadlines by which the new ones must be finalized.  The initial scoping phase has begun for activities along the Atlantic Coast and around Hawaii and off Southern California, including some public hearings and fall deadlines for initial comments, which will inform the first Draft EIS’s for each area. The Portland (Maine) Press Herald covers the Atlantic process (and here’s a link to the Navy’s Atlantic Fleet Training and Testing EIS page) and the San Jose Mercury News chimes in on Hawaii and SoCal, which generated separate EIS’s in the initial round, but will be combined this time into a Hawaii-Southern California Training and Testing EIS.

Navy enviro mag features beaked whale research, with a slant

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The Spring 2010 issue of Currents, the quarterly magazine published by N45, the Navy’s environmental readiness division, features a long article on recent research by Ted Cranford of San Diego State University, which is revealing new details about the anatomy of beaked whales.  Cranford has developed an innovative technique to use x-ray CAT scanners designed to scan rocket motors, and with the data garnered there, is working with an expert in Finite Element Modeling (FEM) to model the ways that sound moves through and around the jaws of beaked whales before reaching their ears.

The results are not all that surprising, in a big-picture way: indications are that the whales’ auditory system filters sounds so that frequencies used in communication and echolocation are accentuated, with other frequencies dampened.  The frequencies used by mid-frequency active sonar, which are near the low end of beaked whales’ auditory range, are filtered by the sound transmission path, so that they impinge on the ear at levels 6dB or more lower than they arrived at the whale’s jaw.

The article doesn’t specify the sound levels used in the tests, to help us compare these results to what animals experience at sea. However, the captions and text repeatedly frame the results to mean that mid-frequency sonar is “largely filtered out before reaching the ear.”  The implication that a 6dB, or even greater, dampening largely removes the signal seems quite misleading; rather, only near the very faintest received levels that would be heard will the dampening render them inaudible.  It’s unsurprising that these frequencies are not of inherent interest to the whales, and it’s reassuring that their anatomy may help protect them from direct physiological damage by such sounds.  But clear behavioral responses to mid-frequency active sonar signals tell us that they clearly hear them, and respond more dramatically than most others to these sounds.  Perhaps these test results could also suggest that beaked whales are especially sensitive to sound in general, or to these sounds at the low end of their audible frequency range; for example, harbor porpoises are well-known to react to quieter sounds than many other species, and recent research has shown that they experience temporary hearing loss (TTS) at lower levels as well.  We may be simply learning that when beaked whales are exposed to, say, 160dB sonar signals, their bodies reduce the sound levels to 150dB by the time it reaches their ear–but they still react, even to this reduced sound.

While the new research is fascinating in its own right (and will be even more compelling if ongoing current research validates the modeling being used), it seems that the Navy needs to be careful in how they present the implications.  To imply that beaked whales are “largely filtering out” sonar sounds is no more helpful in fostering informed public and scientific dialogue than the perception that mid-frequency sonar is a “death-ray” for whales.

Currents is well worth following.  Each issue has a column by the Director or Assistant Director of N45, and about twice a year they run extensive features on various ocean noise topics:
Currents main web site
Spring 2010 feature on Ted Cranford’s research
Winter 2010 feature on Dave Moretti and the Navy’s Marine Mammal Monitoring program, including various tagging programs (Dave raised the “death ray” perception in his interview)
Winter 2009 feature on the Navy’s Marine Mammal Science program

AEI annual report, Ocean Noise 2009 is now available

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The Acoustic Ecology Institute has published Ocean Noise 2009, the fourth in its annual series of reports reviewing new research and regulatory developments in ocean noise. AEI’s annual recaps are widely anticipated and circulated among ocean noise scientists and regulators, as well as within NGO and journalist communities.

The report can be viewed or downloaded as a 45-page PDF, or viewed in the SlideShare plug-in, below.

This year’s report includes coverage of two ongoing issues, seismic surveys and Naval active sonars, with particular focus on the Navy’s continuing roll-out of Environmental Impact Statements for its offshore training ranges and the targeting of Columbia University’s seismic research vessel by environmental activists.

This year’s report introduces a new feature that will be of special interest to journalists: AEI Resource Collections on two topics that will be central to ocean acoustics policy and research in the coming years.

More details below the fold Read the rest of this entry »

MEAM newsletter provides great status report on Marine Spatial Planning around the world

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The most recent issue of the Marine Ecosystem and Management newsletter (download here) has several features that offer a good sense of current efforts to adopt Marine Spatial Planning (MSP) and its related management principle, Ecosystem Based Management (ESB).  The lead article centers on reports from Massachusetts, Norway, and Germany, each oriented toward the relationship between MSP and ESB.  Shorter pieces include interrviews on related topics and direct readers to recent management plans, proposals, and reports by the US Federal Government, the State of Massachusetts, and Papahanaumokuakea Marine National Monument in Hawaii.  For more on MEAM programs and publications, see the MEAM website.

Navy plans to add sonar training in Gulf of Alaska spurs local concerns, as NMFS prepares to issue permits

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The final EIS in the Navy’s multi-year effort to get its training activities into legal compliance with NEPA requirements is heading for the finish line.  Adding to the drama, however, is the fact that the Navy is pushing to introduce active sonar training into the Gulf of Alaska—while previous EISs at other training ranges proposed continuing sonar training at or near levels that have been taking place for years, the Alaskan proposal would bring sonar training for the first time into Alaskan waters rich with marine mammal habitat.  While the Alaskan range where sonar training would take place is relatively small compared to many of the other ranges on the east and west coasts of the continental US, it is within dozens of miles of key whale habitat, and locals have expressed much concern at public hearings.  For more detail, see these links to Alaskan newspaper coverage.



Meanwhile, as the Navy completes the EIS, it has also applied for the Incidental Harassment Authorization from the National Marine Fisheries Service, which announced in early February its intention to issue a Letter of Authorization to permit Navy activities as planned from December 2010 to December 2015.  The Navy estimates that its covered activities will take individuals of 20 species of marine mammals (15 cetaceans and 5 pinnipeds) through Level B behavioral harassment. “Further, the Navy requests authorization to take 3 individual beaked whales (of any of the following species: Baird’s beaked whale, Cuvier’s beaked whale, Stejneger’s beaked whale) annually by serious injury or mortality.” See the Navy’s IHA application here, and NMFS notice of intent to issue the LOA here.

NRDC, allies take Navy to court over training range near right whale habitat

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The new Navy Undersea Warfare Training Range (USWTR), being planned for off the coast of northern Florida, has hit a roadblock that’s been fairly visible since the location was announced last July: environmental groups are challenging the permitting process that allows construction to commence before the Navy completes its environmental assessment of future operations there.  The USWTR will encompass 500 square miles, beginning 50 miles offshore, while a key winter birthing and nursing ground for North Atlantic right whales extends out to 20 miles offshore.

UPDATE, 10/2013: Court sides with Navy, USWTR plans continue forward

While the Navy released its final EIS in July (see AEI summary), including its proposed operational and mitigation measures to protect whales, it became clear soon after that the Navy was only applying for permits from NOAA related to construction activities; the Navy said it would apply for permits to allow actual Navy training activities in 2012 or 2013, in advance of planned opening of the range in 2014. (Update, 2015: the USWTR website now estimates that operations will commence in 2019; no operations permits filed yet.) The EIS indicates that the range will be heavily used:  up to 480 anti-submarine mid-frequency active sonar exercises per year, including 100 ship-based events (2/week on average, lasting 3-4 hours each).

From the start, NRDC and other environmental groups questioned the Navy’s legal standing to commit to $100 million in construction costs before receiving National Marine Fisheries Service (NMFS) permits that would approve their plans for operations, including safety measures to protect marine life.  The new lawsuit alleges Read the rest of this entry »

NOAA steps up, announces new active sonar oversight with possible off-limits areas

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NOAA Administrator Jane Lubchenco has announced a series of sweeping new initiatives designed to push the Navy forward in its efforts to understand and mitigate the impacts of mid-frequency active sonar on marine mammals.  In response to a request from the Council for Environmental Quality (CEQ), which asked NOAA to conduct a comprehensive review of this controversial issue, Lubchenco outlined several important new initiatives which mark a more active role for NOAA in moving both the science and policy efforts forward.  Previously, NOAA had worked closely with the Navy on its Environmental Impact Statements, but had largely rubber-stamped the resultant Navy mitigation plans, which consistently rejected any alternatives that set biologically important portions of US coastal zones off-limits to sonar training.

The new NOAA initiatives include four key elements, three of which dovetail closely with long-time concerns and requests from environmental organizations for NOAA to more actively protect areas of biological significance from both Navy and oil and gas noise, and three of which will help fill key data gaps identified by research scientists over the past decade.

  • First, NOAA will work with other civilian agencies (e.g., MMS) to reinitiate comprehensive aerial cetacean and sea turtle surveys, in order to establish more fine-scale population estimates, especially in Navy training ranges.  Currently, many Navy EISs rely on coarse, regional population estimates, leading to unrealistic estimations of population density being spread evenly across large areas.
  • Second, NOAA’s National Marine Fisheries Service will host a workshop aimed at developing a plan to create a comprehensive “ocean noise budget.”  This is a long-time desire of both researchers and environmentalists, and would identify areas in the ocean where human noise is relatively sparse, as well as areas in which new human activity would not add substantially to already high noise levels.
  • Third, another NMFS workshop will be organized to identify marine mammal “hot spots” of particular biological significance.  All three of these initiatives tie together nicely to bring acoustics into the Obama administration’s stated aim of moving toward more coherent Marine Spatial Planning, a sort of ocean zoning approach that would help guide human activities toward areas where they will have less impact on animals.  In a clear indication that NOAA may take a more proactive role in pushing the Navy to leave some areas out of its training zones, the letter stresses that “Protecting important marine mammal habitat is generally recognized to be the most effective mitigation measure currently available.”
  • Finally, NOAA has already begun taking an active role in ongoing meetings between the Navy and the National Resources Defense Council; these meetings were part of a legal settlement and are designed to resolve outstanding differences about Navy active sonar operational and mitigation measures.  Lubchenco notes that “NOAA’s participation will enhance these discussions and help resolve differing views….I also expect the Navy to be open to new ideas and approaches to mitigation that are supported by the best available science.”

Indeed, including “spatio-temporal restrictions” (areas or times when activity is prohibited) in active sonar permitting has been a major sticking point between the Navy and NRDC and other environmentalists, and is something the Navy has consistently and explicitly rejected in the first round of sonar EISs, which have been finalized over the past year for most of the key Navy ranges (California, Hawaii, East Coast and just this week, the Gulf of Mexico), none of which included any limits on where and when the Navy could do sonar training. “The Navy’s Southern California range is over 120,000 nautical miles in size — about the size of California itself,” NRDC’s Michael Jasny points out. “The Bush administration did not put a square mile of this vast area off limits to sonar.”

All in all, this is a remarkable and very productive first step for this administration as it enters the long-contentious waters of active sonar regulation, ocean noise in general.  You can download Lubchenco’s detailed letter at the NOAA website.

Bias in Military (or Conservation) Funded Ocean Noise Research

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(this item first appeared in AEI’s lay summaries of new research)

Wade, Whitehead, Weilgart. Conflict of interest in research on anthropogenic noise and marine mammals: Does funding bias conclusions? Marine Policy 34 (2010) 320-327.

In the United States, the US Navy funds about 70% of the research into the effects of ocean noise on wildlife (and half, worldwide). For many years, conservation groups have questioned whether this preponderance of funding is skewing research results, whether by constraining the types of questions being studied, or by leading researchers to downplay negative impacts of noise in order to continue receiving funding. The authors of this new study report a significant correlation between Navy funding and results reporting “no effect” of noise, based on their analysis of  several wide-ranging reviews of ocean noise science, and of the primary research papers cited in these reviews.  While the data behind their conclusion is clearly explained, the results don’t look nearly as clear-cut to me; I question the comparability of the five reviews used, and while the trends in primary papers is more obvious, it’s hard to ignore the fact that the majority of military-funded papers still found that noise had effects.  Indeed, as the authors make clear, it’s the conservation-funded reviews and primary research that is most clearly one-sided in its results (though there are good reasons for this, also fleshed out by the authors and in AEI’s commentary below).  In AEI’s view, studies like this – and indeed, reviews such as those considered here – are diligent exercises in quantifying an issue that has become, for all practical purposes, an exercise in divergent world views and beliefs talking at and past each other.

This post includes more analysis and interpretation by AEI than we generally include in our science summaries; it’s a long read, but the issues that triggered this study are important ones. Though the clear-cut results reported here are difficult to take at face value, it is well worth considering the underlying forces that drive tensions between environmental groups and Navy/industry actions in the seas.  While primary research and even literature reviews funded by the military don’t appear overly biased toward finding no effect (since in both cases, they include far more results showing effects than not), it remains that in practical terms, the EIS’s generated by the Navy and the mitigation measures imposed by regulators on both military and oil and gas activities are largely grounded in the belief – and regulatory determination – that any effects of these activities are “negligible,” to use the formal term. Thus the focus of the conservation community on funding research and publishing overviews that emphasize credible studies outlining observed negative effects is understandable.

Of special note is that the authors did not find any strong trend toward bias of results reported by independent, academic researchers receiving Navy funding for research studies – these studies showed a similar proportion of effect and no effect results as studies funded by neither the military nor conservation groups (though when comparing military-funded studies with all the others, including consevation-funded, a non-statisticially significant trend of 1.64 times more “no effect” findings was observed).  This should diffuse widespread concerns that cash-strapped academic researchers are “cooking the books” or avoiding publishing negative findings in order to retain Navy funding (though it is perhaps unsurprising to note that few if any key Navy-funded scientists are among the researchers who are willing to speak out publicly to push for stronger regulations on ocean noise). The authors conclude that “much of the bias in military-funded research was in work carried out at military institutions, rather than in studies funded by the military but carried out at universities and other institutions.”  Thus, research coming directly out of military offices is likely to remain less reliable as representing “the whole picture,” as may research entirely funded by conservation groups. Still, by integrating and considering the full range of studies reported in all of these reviews, the public can get a pretty decent picture of current state of our understanding of the effects of ocean noise.

Of note, though, is that the proportion of “no effect” to “effect” findings is slightly lower in military-funded studies. In addition, military-funded studies are three times as likely to report BOTH effects and lack of effects in a single paper; this could indicate either a more careful assessment of the margins where effects are just noticeable, or a tendency to split the difference in order to either underplay the effects or accentuate the non-effects to assuage funders.

While ocean noise issues came to public awareness after a series of stranding deaths and lawsuits, the fact is that deaths and injuries caused by noise are very rare.  Even the leading environmental activists have shifted their focus, and today nearly all of the controversy over military and oil and gas noise boils down to differing interpretations of how important moderate behavioral changes are, and whether they should be avoided or not. And science is nearly incapable of shedding any definitive light on how important behavioral changes are, thus leaving the two sides largely reliant on their divergent faith: the Navy and oil industry’s faith that the behavioral changes are transient and negligible, and environmentalists’ faith that chronic behavioral disruption by human noise is bound to have negative consequences. Meanwhile, ethical questions about humanity’s relationship to the natural world are outside the bounds of discussion on one side, and central to the whole discussion on the other.  This is not as black and white a picture as either side may paint, but it’s where we are.

For AEI’s full summary and discussion of this important new study, dive in below the fold…..

Read the rest of this entry »

MMS acoustic monitoring workshop includes AEI ocean noise report as key reading

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Thanks to Brandon Southall’s blog on his new SEA-inc website, which is fast becoming one of the best places to stay abreast of key ocean acoustics research, I heard today the details of what’s planned at the upcoming Minerals Management Service three-day workshop on Acoustic Mitigation and Monitoring Systems for Marine Mammals.  The workshop website now has the agenda online, and will include links to conference documents.  I was surprised and delighted to see that my most recent annual ocean noise report is first on the list of Background Documents to be read by attendees! This report, Ocean Noise 2008: Science, Policy, Legal Developments, can be downloaded from the conference site; it is also available, along with its brethren from 2006 and 2007, at AEI’s page on  Several of my conference Powerpoint presentations are also now available for viewing and download as well, at AEI’s SlideShare page.


The three-day workshop takes place in Boston later this month, and is bringing together most of the key players in the field, including Southall, Cornell’s Chris Clark, Oregon State’s Dave Mellinger, Aaron Thode of Scripps, Leila Hatch of Stellwagen Bank, passive device designers Peter Stein and Gordon Hastie, and several key oil and gas industry players, including Bill Streever (check out his great new book on the north, entitled Cold), David Hedgeland, and Bernard Padovani.

Mediterranean Beaked Whale BRS Cruise: No Tags, New Passive Monitoring Technique

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A five-week beaked whale Behavioral Response Study in the Mediterranean concluded in early September with a mixed bag of results: while researchers were unable to affix D-tags to any beaked or pilot whales, they were quite successful in using a new mobile Passive Acoustic Monitoring system which could be very useful in years to come. The study was largely aiming to track whales’ responses to various (low to moderate) levels of mid-frequency active sonar sounds using D-tags on the animals; previous Behavioral Response Studies using such “controlled exposures” have taken place on Navy instrumented ranges where the local populations are presumably familiar with sonar sounds, so they may respond differently than whales who have not heard these sounds before.  However, due to many periods of rough seas, as well as the inherent difficulties of finding, getting close to, and attaching tags to beaked whales (who dive for over an hour and come to the surface only briefly), no D-tags were deployed on whales, and no controlled exposures took place. However, a document prepared before the cruise, summarizing previous BRS results, is well worth reading: see especially page 8, which includes a detailed analysis of beaked whale responses to sonar and orca sounds: in both cases, the whales cut short foraging dives, but returned to the surface more slowly than normal, not more steeply as is sometimes assumed, and they clearly moved directly away from the sounds.

Beaked Whale (click for cruise blog home page)

Beaked Whale (click for cruise blog home page)

However, researchers made the most of two other purposes of the cruise, both of which made use of a new passive acoustic monitoring technique.  The research took place on an extremely quiet research vessel, from which two hydrophone streamers were deployed, each of which had two hydrophones on it.  This gave listeners on the ship four separated sources from which to record and analyze sounds, so that most sounds could be quite well localized (direction and distance).  In addition, researchers deployed floating “sonobuoys” that provided more listening stations during times when groups of beaked whales were nearby.  This network of hydrophones provides much of the information that is provided by permanent bottom-mounted hydrophones on Navy ranges, and offers the potential to both find and monitor beaked whales in any location.  The hydrophone arrays were also collecting basic sound budget data, which will provide a better sense of the noises (both natural and man-made) that ocean creatures hear on a routine basis.  Click through for links to specific blog posts of interest, and a description of one day’s close encounter. Read the rest of this entry »

UK War Games Near Dolphin Conservation Area Spur Concern

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UK environmental groups have raised concerns about the move of a Europe’s biannual Naval exercise to waters outside Moray Firth, which is home to Scotland’s only bottlenose dolphin population, and an area in which an increasing number of marine species has been seen in recent years. Operation Joint Warrier will involve 20 ships, 4 subs, and 40 aircraft, and lasts from October 13-22.  Sarah Dolman, The Whale and Dolphin Conservation Society’s noise campaign manager, said that a full environmental assessment should have taken place before any such operations near a Special Conservation Area, continuing that ‘the Ministry of Defence should ensure compliance with legislation before it moves its exercise into this important, and protected habitat.”  A spokesman for the MOD says that active sonar will not be used within the Firth, and is limited areas more than 30 miles from the Conservation Area, assuring that noise will be within tolerable levels within the Firth’s important habitats.  After a stranding event last summer which was never conclusively tied to sonar, but appeared related to similarly distant military exercises, the area will be closely watched by all this month, I’m sure. For more detail, see articles in The Telegraph and BBC.

China, US Discuss LFAS in China EEZ

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During bilateral meetings on maritime safety, China asked the US to phase out surveillance activity using Low-Frequency Active Sonar near its coast.  Over the past year, there have been five incidents in which Chinese ships (Naval and fishing boats) harassed the USNS Impeccable, one of two US ships equipped with LFAS, and other Navy ships.  The Chinese object to surveillance activity within its EEZ (Exclusive Economic Zone), which extends 200 miles from each country’s coast; the US contends that such activity is only barred within the 12-mile territorial waters zone.

USNS Impeccable (US Navy photo)

USNS Impeccable (US Navy photo)

Navy survey ships were harassed five times this year by Chinese naval and civilian vessels as well as military aircraft in the South China Sea and Yellow Sea – in one case 75 miles south of Hainan island, the location of a strategic Chinese Navy base which reportedly houses ballistic missile submarines. Beijing said at the time that the unarmed Impeccable, was carrying out “illegal surveying” in its EEZ, violating Chinese and international laws. The U.S. Navy says the Impeccable is designed to detect quiet foreign diesel and nuclear-powered submarines and to map the seabed for future antisubmarine warfare purposes.

The key bone of contention is that the Chinese do not accept that the Impeccable’s activities fall under recognized right of navigation in EEZ waters; the U.N. Convention on the Law of the Sea (UNCLOS) provides for “freedom of navigation and overflight” in EEZs. It says military activities inside EEZs must be “peaceful” and must not harm the coastal state’s environment or economic resources. Read the rest of this entry »

Navy Outlines Recent, Ongoing Behavioral Response Studies

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A detailed article-cum-press release from Navy News provides the most information currently available on three studies that will be central to addressing ongoing questions about the Navy’s assessment of the behavioral responses of whales and dolphins to Navy mid-frequency active sonar. Two of the studies took place on US Navy instrumented ranges during normal Naval sonar training exercises, and the third is a Controlled Exposure Experiment taking place this summer in the Mediterranean.  Both the Navy and outside observers (including AEI) will be looking closely at the results of these studies, since the most contentious aspect of current Navy sonar planning involves identifying the sound levels at which behavioral responses (such as fleeing or suspending foraging) become widespread enough to warrant protective measures.  Current safety guidelines only kick in when whales are within 3000 feet, far less than the range at which behavioral responses occur.  Critiques of current Navy EISs focus on the large numbers of animals predicted to change their behavior, and on a “risk function” developed by NMFS that assumes very few whales are affected at sound levels below 145dB. Read the rest of this entry »

2004 Hanalei Bay Incident Not Related to Lunar Cycle; Sonar Link Remains

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During the 2004 RIMPAC multinational navy exercises in Hawaii, a pod of over 150 melon-headed whales appeared in a shallow bay, far from their normal offshore habitat.  Their agitation was obvious, and one young whale beached and died.  When it became apparent that sonar training was taking place offshore that day, the Navy initially said that the transmissions did not begin until later in the day, but later confirmed that some early-morning calibration of the sonar took place.  A NOAA investigation determined that sonar was the “likely, if not probable” cause for the stranding; this statement was clarified later by NMFS, to affirm that they were not sure of the link.  On the same day, another pod of melon-headed whales had appeared in a shallow bay on the western Pacific island of Rota, spurring speculation that the full moon may trigger this species to undertake feeding excursions into shallow bays, with the Hawaii pod subsequently getting disoriented and panicked (perhaps due to the sonar sounds offshore).  The similarity of the incidents led many observers (including AEI) to be less sure that the Hanalei event could be tied primarily to a reaction to Navy sonar.

A study in the July issue of Marine Mammal Science (and summarized here by ScienceNow), however, puts the lunar theory to rest.  NOAA researcher Robert Brownell examined the two incidents closely, along with 21 other mass strandings of melon-headed whales.  It turns out that the western Pacific population of melon-headed whales often retreat into shallow bays to rest; this trait is not shared by the whales around Hawaii. “That is their normal behavior,” says Brownell. In contrast, the whales’ actions in Hawaii were “identical to those that precede mass-strandings” of beaked whales, with pods swimming agitatedly in tight circles, spy-hopping (rising vertically out of the water), tail-slapping, and vocalizing.”  And, the timing of other strandings showed no correlation with full moons or any part of the lunar cycle.  Figuring out what caused the Kauai whales to strand is important, Brownell says, because so far only mass strandings of beaked whales have been conclusively linked to the Navy’s use of sonar. “It’s a big debate,” says Brownell. “Why are only beaked whales affected and not others? Well, other species are.” Brownell says that melon-headed whales probably aren’t affected as often by naval sonar exercises because, unlike beaked whales, they usually hang out far from shore. He thinks “it was purely a coincidence” that melon-headed whales were near Kauai the morning the Navy ran its sonar test. “If any other cetacean species had been going by that morning, the same thing would have happened,” he says. (Ed. Note: this statement is somewhat more speculative than scientists are usually willing to make…while sonar has induced agitated reactions in orcas who did not strand, beaked whales have not been observed prior to strandings.  And, the final statement is likely to drive other scientists crazy, thanks to its likely unwarrented certainty.  Still, the main point holds true: reactions to sonar are not limited to beaked whales, and this incident is becoming one of our clearest indications of this; other species have died in some multi-species strandings that are considered likely sonar-related by many non-Navy observers, and this summer Minke whales were seen racing away from sonar-emitting ships in the UK)

The U.S. Navy disputes Brownell’s paper. Chip Johnson, a Navy marine scientist, spun the news as well as can be expected, saying that the new study only “contributes more uncertainty” about what happened to the melon-headed whales that morning, presumably because it highlights previously unknown behavioral differences between different populations.  It does, however, seem to put to rest the idea that the two events that day, 6000 miles apart, represent a similar behavioral response to prey or the moon, since the whales in Rota were resting, and the ones in Hawaii were clearly agitated.  Spokesmen from various environmental organizations say this study helps move the Hanalei Bay event more clearly into the sonar-induced category; Michael Jasny of NRDC said of the uncertainty raised by the two events, “It’s really no longer an issue. The question is now, ‘What can be done to fix the problem?'”

Navy to Avoid Puget Sound in Sonar Training, But…

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After suspending the use of mid-frequency active sonar training activities in Puget Sound in the wake of an incident in 2003 in which sonar sounds appeared to agitate a group of orcas, the Navy confirmed this week that a new sonar training plan, with permits to be issued by the National Marine Fisheries Service, will keep future sonar training off the West Coast, and out of inland waterways. Chris Dunagan at the local Kitsap Sun gives the announcement his usual thorough coverage, including context from the past, as well as zeroing in on a key passage in the Navy’s public statement: “Any use of high- or mid-frequency active sonar for training purposes in Puget Sound would be beyond the scope of this permit,” the statement says. “However, outside of this permit, active sonar is used within Puget Sound for safety and navigation; testing; maintenance; and research, development, test and evaluation (RDT&E).”  An incident in January of this year, during which mid-frequency active sonar was heard through a night, was part of RDT&E activities.  Dunagan explores the question of these multiple activities a bit more in an accompanying blog post.

Georgia Questions “Considerable Speculation” in Navy sonar range assessment

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The Navy is facing some push-back from the states of Georgia and Florida in the initial stages of gaining the necessary approvals for proceeding with their plans for a 500 square mile training range offshore from Jacksonville.  The Navy had hoped to have the states’ comments in hand by this week, but Florida expects to take several more weeks to assess the Navy’s plan, and the head of Georgia’s Coastal Resources Division submitted comments with fairly strongly worded notes of skepticism regarding the Navy’s just-released Final Environmental Impact Statement:  the letter says that the Navy’s forecasts “require considerable speculation and are insufficient to assess the anticipated impacts.”  Sonar travels differently depending on water conditions, and the Navy hasn’t done real-world measurements off Jacksonville to see whether its models of what will happen are right, said Clay George, a Natural Resources biologist. George also noted that while the designated critical habitat for wintering right whales extends to just 20 miles offshore, biologists have not done much surveying further offshore, and so the whales may well inhabit waters closer to the range.  Because of such shortcomings in the Navy’s analysis,  Georgia’s Department of Natural Resources wants long-term monitoring of how the range affects endangered right whales that raise their calves offshore from the two states each winter.  If the whales were harmed by sonar that would be used in submarine exercises, training at the range should change, the state told Navy officials in a letter last week. (Ed note: the Navy’s analysis does take account of uncertainty about the area inhabited by grey whales in winter by assuming that some will occur even within the training range; however, they also assume that virtually no whales will be affected by sounds traveling into the critical habitat, and they explicitly reject the option of doing less training in winter months when the whales are present. For more on the key question of distant effects of sonar sounds, scroll down to the July 24 post below, or click here to read the earlier post.)

In related news, the Florida Times-Union also reported that the Navy will separate its permit applications for construction and operation of the range.  The Navy expects NOAA approval for construction this week, but does not plan to apply for permits to operate the range until 2012 or 2013.  Likewise, the State of Florida this week announced that it will follow the Navy’s suggestion to similarly  follow a “phased” approach to issuing the necessary permits. In addition to sonar issues, Florida officials agreed to put off final judgments about how fast ships should travel in the training range, whether low-flying helicopters using the range will disturb right whales and how much debris from the training exercises will affect coral and other protected species on the ocean floor.  This may trigger legal challenges, though, as Catherine Wannamaker, an attorney at the Southern Environmental Law Center responded to the news by saying that the phased approach “artificially separates the impacts to endangered species … that will result from both construction and operations.” According to Wannamaker, the Endangered Species Act doesn’t let the Navy spend money on the range without the National Marine Fisheries Service agreeing the project won’t jeopardize endangered species. (Ed. note: It appears from AEI’s admittedly naive legal perspective that the question of exactly what operational and mitigation measures are appropriate for the site can best be addressed at the time of the later permitting.  At this stage, there is little doubt that the Navy’s need for a littoral instrumented range is real and that the USWTR will proceed; the questions will include how much limitation on sonar activities should be imposed on the range while right whales are nearby.  There is no reason this cannot be addressed later, and indeed, there is likely to be better information at that time, including a revised Risk Assessment curve, which could well lead to more caution being imposed.)