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.

A 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.

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.

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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Two 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.

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.

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.

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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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):

http://www.facebook.com/home.php#!/pages/Behavioral-Response-Studies-of-Marine-Mammals/153316228012219

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:

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:

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.

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.

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.

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.

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.

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

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.

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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.

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.

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.

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.  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 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.

(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 »

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 DocStock.com.  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.

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)

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 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.

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)

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 »

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 »