From August 15-20, 250 ocean noise researchers, agency staff, and NGOs gathered in Cork, Ireland for the 2nd International Effects of Noise on Aquatic Life conference.  I’ll be posting more on the confab later, but for today I wanted to note the quick jump made by two of the folks I was most glad to finally meet, each of whom headed directly out into the field upon their return home from Cork.  Their field blogs certainly remind me that their lives are VERY different than mine, where the post-conference field work involves garden beds burgeoning with beets, carrots, tomatoes, and basil, along with today’s excursion to town, where I write from a shaded cafe table looking up at the Sangre de Cristos in full autumn sun.

After leaving Cork, Sarah Dolman touched down only briefly in Edinburgh before heading off to the beautifully foreboding Outer Hebrides, the islands off the country’s northwest shore, where her team is based on the island of Harris and Lewis. The research task at hand is a simple population survey, though in the North Atlantic, it’s often not so simple!  The team is posting entertaining recaps of their days on the water (and sometimes limited to cliff-top surveys from shore) at the Whale and Dolphin Conservation Society field blog.  Lots of great pictures and tales!

Meanwhile, Brandon Southall is basking in relative comfort along the Southern California coast, where the main meteorological challenge has been morning fog.  He’s leading the most extensive Controlled Exposure Experiment (CEE) yet undertaken, and is posting daily on his SEAblog.  Alternatively known as a Behavioral Response Study, the study aims to place temporary acoustic tags on several species of whales, in order to track their responses to various sounds, which are projected in a controlled way into the water near the tagged whales. The tags record the actual received level of sounds, while also tracking the animals dive patterns and vocalizations.  While the project descriptions do not specify the sounds being played, earlier studies have used mid-freqency active sonar sounds, as well as the sounds of predators (orcas), and various artificial sounds; the experiment protocol starts sounds at 160dB, increasing gradually to 210dB re 1uPa, and limits sound exposure to 30 minutes, with long pre- and post-exposure periods that should clarify which behaviors are clearly in response to the sounds.  This 6-week project builds on earlier work done on a Naval range in the Bahamas, during Hawaiian Naval exercises, and last summer in the Mediterranean; while these earlier studies focused primarily on very hard to tag beaked and pilot whales, the current study is focusing largely on much more numerous and easier to approach larger whales.  Between August 22 and the August 30, they managed to deploy 29 tags and do 14 sound exposures with individuals of three species; by the conclusion of the project on October 1, SOCAL-10 will have a far more robust data set of behavioral responses to sound exposures than has ever been available before.

Attaching two tags to a blue whale (Photo courtesy J. Calambokidis, Cascadia Research)

For more on the SOCAL-10 study, see the SEAblog daily reports, plus:
This 18-page pdf summary of the project, including a good overview of the results of previous CEEs
Brandon’s Vimeo page, currently featuring 6 videos, including an hour-long introduction to the project  (again, including slides of data from previous CEEs)and a series of short videos from the field, including one of a tag being placed.

Using the same recording units that have provided a rich stream of new data on the effects of shipping noise on whale communication off Boston, Chris Clark of Cornell is spearheading a new project to study the acoustic ecology of the Gulf of Mexico.  According to a press release from Cornell:

“The team will anchor 22 marine autonomous recording units (MARUs) to the sea floor in an arc stretching from Texas to western Florida, along the edge of the continental shelf. These units will record underwater sounds for three months before they receive a signal to let go of their tethers and pop to the surface for retrieval. After analyzing the data, the team will deliver a report to NOAA and other agencies involved in the oil leak response. The MARUs will listen for endangered sperm whales and a small population of Bryde’s (BRU-des) whales. They will also pick up sounds of fish and ship traffic. Some devices will be placed in areas apparently unaffected by the oil to collect “control” site information; others will be close to the gushing well. The goal is to document the state of the sounds in the ecosystem over an extended period of time and compare them with known information of the oil spill.

Researchers deploy recording units (Photo: Danielle Cholewiak, BRP)

“This will be the first large-scale, long-term, acoustic monitoring survey in the Gulf of Mexico,” Clark said. “We can provide one more layer of understanding about this ecosystem, using sound to measure animal occurrences, distributions and communication, as well as background noise levels from shipping and weather, and perhaps visualize how these features are being influenced by the oil. The whales are like oversized canaries in the coal mine — they reflect the health of the environment they live in.”

An impressive array of 76 acoustic monitoring buoys is planned to be deployed in Scotland’s Moray Firth this summer, to listen in on local populations of dolphins, porpoises, whales, and seals.  Scientists from Aberdeen University will place the recording devices up to 70 miles offshore, expanding on work carried out last summer on a smaller scale.  Dr. Paul Thompson, one of the lead researchers, explains: “This will help us get a better understanding of the distribution of particular species. We will be looking at the impact primarily of oil and gas exploration, but also the development of wind farms. During construction phase of these developments, it can be quite noisy and affect marine mammals. It will allow us to get a better understanding of how they use different parts of the Moray Firth and to understand what parts are most important” to each species.  Read more at The Scotsman.

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

Natural England, a recently-established “statutory consultee” charged with advising the UK government on projects that may affect wildlife or the English countryside experience, has published a document that outlines its approach to providing guidance on wind farm siting.  The guidance considers both established parks and other unprotected wild lands and geo-diversity sites, as well as areas of deep peat, and areas of hightened bird sensitivity.  It also mentions previously-mapped areas of the greatest tranquility, though it is not clear just how much weight each of these various designations will carry as it balances the many factors that go into its recommendations.

Read more about the guidance on this post at New Energy Focus, or read Natural England’s press release here.  You can download the guidance document from this web page.

Paul Spong and Helena Symonds are legends in the field of whale research; since the early 1970’s they’ve dedicated themselves to studying orcas from their independent lab on an island between Vancouver Island and the mainland.  Over those many years, they’ve accumulated 20,000 hours of tapes, which are now being digitized and cleaned up (to remove hiss and other noise and make the orca calls more prominent) by George Tzanetakis of the University of Victoria.  A recent article in the Toronto Globe and Mail focuses on Tzanetakis’ work, which is being posted online for researchers and curious listeners as the Orchive.  The entire collection isn’t online yet, but there’s plenty!

Those of us  who know the pleasures of cueing up Newport Jazz or good ol’ Grateful Dead shows from online taper archives like Archive.org and Bill Graham’s Wolfgang’s Vault will be familiar with the scope of this project: right now I’m nearly half-way through a 45-minute “set” from 9/1/05 known on the Orchive as Tape 449A.  As with jam band and jazz taper archives, the quality is decent though not crystal clear, creating a great background stream of pleasurable audio, ebbing and flowing from quiet and calm to more active, interspersed with moments of truly exciting interplay and melodic joy.  The audio is presented with a basic spectrogram, and even field notes (the scientific version of Dick Latvala’s show notes):

A sweet set from 9/1/05

Visit the Orchive!

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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A radical new approach to offshore wind turbines is being developed by UK researchers could solve one of the major challenges of offshore wind development.  The Novel Offshore Vertical Axis (NOVA) Demonstrator puts the moving parts at the bottom of the unit, greatly simplifying maintenance. (How they will deal with corrosive factors will be interesting to see!)  The units are 100m tall, and are planned to generate 5-10MW; however, they are some years away, with the initial test model planned for deployment in 2015.

Aerogenerator NOVA concept

For more on this new design, see this article in the Guardian and the NOVA website.

This one slipped past me when it happened last June, but it’s well worth noting now.  Complicating assessments of the risks of bird deaths at wind farms is the fact that two-thirds of migrating bird species migrate mainly at night; Cornell’s Bioacoustics Research Program, which has already done groundbreaking work in elephant communication and underwater listening systems, has proposed that combining their autonomous recording devices with radar data could provide the missing information on exactly when and where concentrations of migrating birds may exist near proposed wind farms.

A compelling animation highlights the large-scale patterns: The color-coded radar map illustrates areas of precipitation over the coasts as well as vast movements of tens of millions of birds, bats and insects across the entire country. In the densest areas, the color-scales indicate movement of 2,000 birds per cubic kilometer. ”You’re talking about a massive movement of birds overnight,” said post-doctoral fellow Andrew Farnsworth.

Radar imagery of night-migrating birds, bats, and insects

Although radar data can show the magnitude, location, timing, speed and direction of migration patterns and provide information on key stopover sites, they do not identify types of birds or accurate flight altitudes, Farnsworth said. But combining radar data with data from flight call recordings and tracking tags on birds could allow researchers to identify many species in key areas. Bioacoustics program director Chris Clark added that recorders are cost effective, can be automated for many months at remote sites, provide data on many species simultaneously, increase the probability of tracking secretive and endangered species, and could allow regulatory agencies to develop computer models to assess risks to birds from wind turbines. He acknowledged, however, that using such acoustic technology could produce a massive “data crunch”; a single microphone over a three-to-four-month period can record 120 to 140 gigabytes of data, so data from several hundred microphones would be too much to process without advanced software. Also, researchers would need to better recognize the wide variety of flight calls and learn to integrate data from radar with those from acoustics and tracking tags, he added. More research is needed, Clark stressed, to determine at what altitudes species tend to fly and whether birds sense turbine blades and avoid them.  Read full account of the presentation in the Cornell Chronicle, with link to the radar map animation.

The latest podcast from Touch Music, a British label that’s been the source of many of the best soundscape releases over the past decade, is a wonderful 45-minute radio documentary style piece from Chris Watson, who recently spent time in Antarctica.  The Disquiet blog has a nice introductory post and embedded audio, so go there to listen to Chris share his experiences in words and sounds.  His narrative descriptions of landscape and his travels (including flying into the south pole), and of course his stellar recordings of penguins, seals, and creaking ice, are well worth spending an hour with!

While pondering Antarctica, I want to also mention a recent CD release that will appeal to the science-minded among you: Andrea Polli, an educator and sound artist with a special interest in sonification of scientific data, especially as related to climate change, spent much of her time in Antarctica following working scientists around as they pursued their many fascinations.  Her CD, Sonic Antarctica was released last year on the fantastic German Gruenrekorder label; the CD is a uniquely satisfying immersion into the sounds and science of the southern continent.   Andrea’s site 90 Degrees South is also a great place to go to read and hear posts on her time there, and to view a short film she created, Ground Truth, which focuses on why  people go to remote, uncomfortable and often hazardous locations, to do what is known as ‘ground truthing.’

It seems that hooking a grant-ride on the Antarctic Express has become quite the rite of passage for many sound artists in recent years.  Doug Quin was among the first, going down in 1996 and again in 1999 to be there at the turn of the millennium. More recently,  Craig Vear, from the UK, created the most elaborate artistic response to the place with his DVD, CD, and book Antarctica: Musical Images from the Frozen Continent, which features compelling imagery, historic films, and a half-hour audio-video piece combining field recordings and spoken remembrances from Antarctic scientists.

The latest in AEI’s ongoing series of comprehensive special reports on key topics is finally done!

This one is modeled on AEI’s acclaimed annual reviews of science and policy developments in ocean noise, but focuses for the first time on wind farm noise issues.  The 30-page report covers new research, public concerns, and industry trends over the past year.

Read the report in the embedded pdf reader below, or download a pdf copy.  Click on to below the fold for a table of contents and the report’s brief Introduction.

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This came out in December, but I forgot to post about it then.  The National Park Service’s science magazine has published an entire issue devoted to the NPS’s soundscape studies and programs.

A couple strolls through Cathedral Grove on a quiet morning in winter when visitation is typically low. Signage at the entrance to this area reminds visitors that they are in a quiet zone. (NPS Photo/Lou Sian)

Articles include:

• Measuring and monitoring soundscapes in the national parks
• Integrating soundscapes into NPS planning
• Conserving the wild life therein–Protecting park fauna from anthropogenic noise
• Soundscapes monitoring and an overflight advisory group: Informing real-time management decisions at Denali
• Soundscape management at Grand Canyon National Park
• Generator noise along the US-Mexico border
• A program of research to support management of visitor-caused noise at Muir Woods National Monument

And, as they say, much, much more!  See the issue online here; from there, you can read every article in full. Note that the html views break each article into several separate pages, but you can also view in a “printer-ready” format that loads the entire article into a FlashPaper format, or you can view or download the full articles as pdfs.

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.

I’ve just finished reading what must be the most exciting research paper I’ve seen this year, barely nudging out a similar paper addressing terrestrial noise impacts. A small group of researchers, with Chris Clark of Cornell as the lead author, took a giant step forward in addressing the impacts of ocean noise on the communication ranges of whales.  They came up with a clear and strikingly rigorous set of new metrics that will allow researchers and ocean planners to have a much more practical picture of how numerous noise sources combine to create cumulative impacts on acoustic habitat.  The new approach centers on the “Communication Space” of individual animals, as well as groups, and provides an intuitively obvious way to both imagine and assess the effects of ocean noise – measuring the area in which an animal can hear or be heard by others of its species.

My formal “lay summary” of this paper is reprinted in full below the fold, and I encourage anyone with a deep interest in ocean noise to read through that five-paragraph overview, or to download the paper yourself.  The key takeaway for those of you with a more casual interest in these issues is that in the test case that they used to illustrate their new approach, the researchers found that shipping noise has dramatically different impacts on different species, even though all three species they studied are low-frequency communicators.  In the area off Boston Harbor that they investigated, the critically endangered right whale is by far the most affected by shipping noise: on a day when two ships passed through the area (the average is often six), right whale Communication Space was reduced by an average of 84% over the course of the day, with several hours in which they could hear and be heard in an area less then 10% of that which would be expected without shipping nearby. Since right whales call back and forth to find each other as they form groups for feeding, this is truly worrying (though the key question of how a reduced communication range actually affects animals remains unanswered).  Fin whales and humpbacks were far less dramatically affected, with their Communication Spaces reduced by just 33% and 11% respectively.

These first examples focus on the effects of low-frequency shipping noise on low-frequency communication by large whales, but this approach can easily be used to address mid- or high-frequency noise sources (sonars, airguns) and higher frequency animal sounds such as those used for echolocation, opening a vast and exceedingly useful new doorway for biologists and ocean managers, as well as the general public, to appreciate the impacts of human sounds in the sea.   (click through for complete lay summary)

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A report issued by the American Wind Energy Association (AWEA) and the Canadian Wind Energy Association (CanWEA) purports to assess all currently available research on the health effects associated with exposure to wind farm noise, and concludes that there are no such problems.  The report, funded by North America’s two key wind industry trade organizations, centers on the symptoms of the reported “wind turbine syndrome,” and while it offers a robust critique of the idea that low frequency noise from wind farms can cause direct health impacts, it’s hard to take its message of wind’s “clean bill of health” at face value, thanks to many topics that are ignored or underplayed.  The report minimizes the levels of annoyance and impacts on quality of life reported in other studies, and completely omits any assessment of the most widely reported health-related impact of living near wind farms, sleep disruption. (For more complete assessments of health-related issues related to wind farms and noise, see recent reports from the Minnesota Department of Health report and World Health Organization.)

The authors of the new AWEA/CanWEA report acknowledge that some people may be annoyed by the sounds of wind turbines, but stress that annoyance is not an “adverse health effect.”  They also seem intent on assuring that any mention of annoyance rates is kept to 10% or below, which necessitates some creative re-interpretation of one of their key sources, a recent paper by Eja Pederson that compiled results from three surveys near wind farms in Scandinavia, summarized in October by AEI. In particular, they combine results from two studies in rural areas and one in a suburban area, which Pederson explicitly presented separately, because they illustrate that annoyance rates are far higher in rural areas (since the suburban study had more participants, the overall average is dominated by the suburban results).  In AEI’s view (as regular readers will know), the bottom line in all annoyance studies is that while many (or even most) people who are within earshot of wind turbines are not strongly affected by the noise, a substantial minority (ranging from 5-40% depending on how close they live) are negatively impacted, sometimes to the point of abandoning their homes; our challenge is to decide how many people we feel OK disrupting, and regulating wind farm siting to match that choice.

The report also repeatedly states that “the sound emitted by wind turbines is not unique,” while it elsewhere briefly acknowledges the often fluctuating nature of turbine noise (amplitude modulation) and its role

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