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Maine town stands firm on one-mile turbine setback

News, Wind turbines No Comments »

Each time the residents of Frankfurt, Maine have been asked to weigh in on a proposed wind farm on Mount Waldo, the results have the same: “no thanks”—and by ever increasing margins.  In 2011, an ordinance establishing a one-mile setback passed by 22 votes; the ordinance also set noise limits of 45dB during the day and 32dB at night (a range that’s in line with what turbines would be expected to produce at that distance).  The town was sued by the landowners who were planning to host a six-turbine project; both sides agreed to put the question of allowing the project to go forward to a March 2013 town meeting vote, which fell 47 votes short.  This year, a measure to repeal the 2011 ordinance and revert to state standards (55dB day/42dB night noise limit) was on the election day ballot, and that proposal lost by 138 votes, or 62%-38%.

windagain090414.jpgThe citizens of Frankfurt have spoken clearly and repeatedly.  They have said that they want turbines to stay far enough away from neighboring properties that they will be rarely heard.  While the one-mile setback (and perhaps even moreso the 32dB night noise limit) make the proposed Mt. Waldo project unfeasible, standards such as these are not inherently unreasonable; indeed, several other Maine towns (including Woodstock, Sumner, Rumford, and Clifton) have adopted 4000-5260 foot standards, rather than outright bans.  [The photo simulation above, created by the wind developer, shows a view from about two miles away.] While such standards clearly aim for much smaller impacts on neighbors than more typical 1200-1700-foot setbacks, turbines in the range of a mile away are still a dominant visual presence and can be readily audible; the larger setback/lower noise standards are generally aiming to find a middle ground that allows wind development while minimizing impacts.

The Record Hill Wind Farm in Roxbury is over a mile and a quarter from most homes, and those who spoke up about noise issues early on have found that the turbines are only rarely audible—though they still dislike seeing the turbines over the pond and the string of lights at night.  A look at Google Maps seems to show more homes within a mile of Mt. Waldo than at Record Hill (a dozen or so, rather than a couple), so the option of getting agreements with all of the closer landowners may not be practical.  Across the country, many other towns have weighed the costs and benefits differently and adopted the standard, less restrictive setbacks; they’ve been more willing to accept that a small to moderate proportion of those within a half mile or mile will find the noise intrusive, leading to complaints and in some cases the need to move.  It’s altogether right for towns to make their own choices about how to navigate the grey area of how much visual or acoustic impact they’re willing to live with; Frankfurt and other towns like it are making a clear and reasonable decision.  It’s time for wind developers to accept such choices, choosing sites and designing projects that fit with local sentiments, rather than pushing towns to loosen siting standards simply to make it easier for particular projects to move forward.

UPDATE, 11/5/14: Another Maine town was considering a change in its wind ordinance this week, and that one went the other way, an apt illustration of the self-determination point I just made.  Dixfield had enacted a 2000-foot setback in 2012, but in 2013 the Planning Board was charged with revisiting that decision.  This past summer, a set of amendments were proposed that would have doubled the setback to 4000 feet, and applied more restrictive sound limits as well: 42dB during the day, 35dB at night (again, about what we’d expect at the greater distance).  On Tuesday, in a very high turnout election, the amendments were defeated in a nail-biter, 562 to 557.  So in Dixfield, a 20MW wind project that’s been conducting wind and environmental studies for the past few years still has a relatively amenable path toward approval and construction.

Seabed mining facing high hurdles from NZ EPA

Effects of Noise on Wildlife, News, Ocean, Ocean energy No Comments »

In recent years, there’s been a growing sense of concern in the ocean noise community about the worldwide emergence of plans for mining the seabed for a wide range of minerals.  Some of these plans are moving toward completion, as mining companies have solved the cost and technical complications and begun submitting actual project plans to regulators.  An early glimpse of this process has just emerged from New Zealand, where the EPA is now evaluating a permit to mine rock phosphate offshore from the South Island.  See this article in Pundit (a tamer Kiwi version of Huffington) for a very good summary of the process going on there.

In particular, Pundit’s Claire Browning notes that the first seabed mining proposal to come before the EPA was turned down, and she details some of the extravagant non-acoustic impacts of the current project—the process involves scooping up masses of seabed and dumping most of the material back, creating plumes of debris (including uranium and other heavy metals) in the water column.  All this in a Benthic Protected Area where no bottom-trawling is allowed.  Meanwhile, a consortium of environmental groups is stressing the insufficient acoustic and population assessments included in the application:

…the company had carried out no visual or acoustic surveys to establish what whales were in the vicinity, and there was no empirical data on noise that would be generated by the mining. Instead, CRP contractors had constructed a model extrapolating noise from a shallow-water mining operation, a model that, for example, did not take into account noise from pipes taking sediment 450 metres up to the ship – or back down.

“There are a number of potentially serious impacts on marine mammals. More rigorous environmental impact assessment would be needed to assess the severity of the impacts of this development,” said Ms Slooten.

It’s especially good to see that local watchdogs are thinking broadly about the potential acoustic emissions, including the sounds of material being pumped through pipes; our colleagues at Ocean Noise Conservation have been raising questions about such largely-ignored subsea industrial noise around oil and gas sites for several years.  Also interesting in the Pundit piece is a moderately deep dive into the question of how much the Kiwi EPA is taking the precautionary principle into account; the lack of concrete direction to do so was a controversial element of the statutory directions to the newly-formed agency, but it appears that its decisions are indeed deferring activities that carry uncertain risks to sensitive areas.  It’s worth noting that seabed mining may not always be a bad thing; much terrestrial mining has high environmental and social impact, with the resulting raw material shipped large distances to its eventual markets.  Such pressure may be relieved at times by moving offshore; in this case, the company’s website highlights the benefits of mining rock phosphate domestically rather than importing it from Morocco, the primary current source.  But of course, offshore sites need to be thoroughly assessed, and any new activity directed toward areas that will create minimal impact on marine life.

 

More evidence that ship noise can have dramatic impacts on non-cetacean sea life

Animal Communication, Bioacoustics, Human impacts, Ocean, Science, shipping No Comments »

AEI lay summary of four recent papers:
Simpson SD, Purser J, Radford AN (2014). Anthropogenic noise compromises antipredator behavior in European eels. Global Change Biology (2014), doi: 10.1111/gcb.12685
Voellmy IK, Purser J, Simpson SD, Radford AN (2014). Increased Noise Levels Have Different Impacts on the Anti-Predator Behaviour of Two Sympatric Fish Species. PLoS ONE 9(7): e102946. doi:10.1371/journal.pone.0102946
Nedelec SL, Radford AN, Simpson SD, Nedelec B, Lecchini D, Mills SC (2014). Anthropogenic noise playback impairs embryonic development and increases mortality in a marine invertebrate. Sci. Rep. 4, 5891; DOI:10.1038/srep05891 (2014).
Erica Staaterman, Claire B. Paris, Andrew S. Krough (2014). First evidence of fish larvae producing sounds. Biol. Lett. 2014 10, 20140643.

It used to be that most concern about human noise and ocean life was centered on whales and the two loudest sound sources: sonar and seismic surveys.  But in recent years, we’ve seen a growing wave of studies looking at how chronic, moderate ship noise can interfere with normal behavior and development of other creatures, including squid, fish, crustaceans, and other “lower” species.  Four recent studies add to the list of known or suspected ways that shipping and recreational boat noise may be wreaking previously unsuspected havoc throughout the oceanic web of life.

eelsWEB

The most dramatic results came in a study of eels’ responses to predators (above). When exposed to ship noise, only half as many eels responded to an ambush attack from a predator (just 38% reacted, down from 80%); and, those that did react did so 25% slower than normal. Likewise, researchers tested eels’ ability to detect a “pursuit” predator that follows the eels before attacking; in this case, the eels in ship noise were caught twice as quickly.  Looking deeper, the researchers examined how noise affects metabolic rates, stress, and breathing rates, and an interesting feature of eel life, the preference for using one side of their body when interacting with other eels and when hunting.  The researchers explain:

“In the same way we write using our right or left hands, fish have a preferred side to approach a predator or to stay next to shoal mates with. We watched each eel as it explored a maze in ambient conditions to classify its right or left bias, then we exposed half to ship noise and half to more ambient noise. Their preferences went away when they were exposed,” says Dr Steve Simpson of the University of Exeter, lead researcher on the study. The team suspect this means ship noise affects eels’ cognitive processes, which could mean other processes, like learning, may also be affected. Alongside raised metabolic and ventilation rates, the scientists note the stress being caused by the shipping noise is similar to the levels fish exhibit in ocean acidification studies.

“We know shipping isn’t going to stop, but we can do things like move a shipping lane so it doesn’t interact with the migrations paths of animals,” Simpson suggests. “It’s a pollutant we have more control over than something like atmospheric carbon dioxide. These animals are having to deal with all the stressors globally, so if we can alleviate just one it might give the animals more resilience to other stressors like ocean acidification, which will come later.”

A study of two species of small fish highlights species differences and the ways that noise can alter behavior in unexpected ways.  Here, one species of fish exposed to ship noise actually responded more quickly to the presence of a predator,

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MI turbine suit settled; another lesson in operating too close to already-generous noise limits

Human impacts, News, Wind turbines 4 Comments »

MI Lake Winds under constructionFor the past couple of years the Lake Winds Energy Park in Mason County, Michigan has been embroiled in a contentious dispute about its noise levels (image to left is the “Park” under construction).  In April 2013, five months after the 56 turbines began operating, 17 neighbors filed suit, claiming that wind farm noise, vibrations and flickering lights were adversely affecting their health. A few months later, after commissioning an independent sound study, the Mason County Planning Commission formally declared the wind farm out of compliance and demanded a mitigation plan; the developer, Consumers Energy, disputed the findings yet lost two appeals, one at the Zoning Board of Appeals and one in Circuit Court. During that series of challenges, Consumers developed a plan to modify turbine operations for 7 turbines closest to the four sites where they were found to be marginally too loud.

Marginal is indeed the word: the sound study found 4 locations where the sound level peaked at 0.3 to 1.2 decibels over the 45dBA noise limit (it takes 3dB for a difference between two sounds to be audible); when using 10-minute averages, there were no violations.  The various explanations by the consultant, Brian Howe, illustrated the fine line that the turbine operations were walking.  His report stressed “general compliance with sound level criteria,” and noted that the brief violations “do not represent a statistically significant portion of time and do not indicate a systemic exceedance.” In his initial testimony at an August Planning Commission meeting, he said that there are no recommendations to correct for these times because “there is not a situation where they are predictably going over 45.”  Later, in a November letter to the Commission, after learning that the county had previously decided NOT to allow for occasional exceedances, he stressed that “I can assure the County that competent, material and substantive evidence supports the conclusion that the turbines are not in compliance at certain residences on occasion” and elaborated:

Excursions over 45 dBA should have been anticipated since, as outlined in the acoustic study by Tech Environmental prepared in June 2011, the wind energy park was designed with sound levels identically equal to the 45 dBA criteria at some key receptors with no factor of safety to address the fact that the prediction methodology has a stated accuracy worse than +/- 3 dBA. If Tech Environmental was aware that achieving the criteria even 95% of the time was unacceptable to the County, it would have been prudent to incorporate a suitable safety margin to account for the statistical variation in sound levels.

And this is the first half of the central lesson here: it’s essential that enough of a safety factor is built in to the sound models to account for known variability in sound production (how loud the blades are in various unsteady wind conditions) and sound propagation (how far sound travels as it gradually loses power).  Regular readers will know that variability is indeed, as Howe mentioned, often more than the simplified 3dB margin of error that was neglected here (see AEI’s 2012 report). The second half the lesson is related: when noise limits—for the sound of the turbines when it reaches nearby homes—are set as high as 45dBA, they will be regularly audible at these homes, and likely well above night-time ambient sound levels.  As many acousticians have stressed for years, these situations are very apt to trigger a significant number of complaints, especially if there are dozens of homes in that nearby range.  Here, we had the worst of both worlds: turbine siting plans that pushed sound right at the limit into nearby homes, and a limit that was on the high end of tolerability for many neighbors.  Indeed, after one such cautionary report was presented to the Mason County Planning Board, it decided to lower the limit to 40dB, but that change was revoked after push-back from Consumers Energy.

With this backdrop, this week the 17 original plaintiffs in the noise nuisance lawsuit agreed to a settlement offer from Consumers;

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Ocean observatory audio streams: navies nix bits of data that scientists savor

Bioacoustics, News, Ocean, Science, shipping, Sonar Comments Off

For several years, AEI has been excited about the ever-expanding networks of ocean observatories coming online around the world.  A recent article on LiveScience detailed some of the benefits of the arrays of research stations deployed offshore by Ocean Network Canada, which collect all manner of data: physical, chemical, biological, geological, and acoustic.  Their two networks, the offshore NEPTUNE (left below) and the near-shore VENUS (right below), consist of permanent installations on the floor (“nodes,” shown as orange squares below) as well as mobile moored sensors that may take measurements higher in the water column (yellow dots). A similar US network, dubbed Regional Scale Nodes, is being planned off the coast of Washington and Oregon.

NEPTUNE VENUS

While the observatories are enabling in-depth study of complex process in ways not previously possible (click that link for a glimpse of the amazing topics being explored…yes, do it!), the audio feeds coming from some of the nodes hold special excitement for many researchers. “If you want to study what’s going on in the ocean, the best tool by far is sound,” said Tom Dakin, an acoustic specialist at ONC’s sensors technology development office.”There are all kinds of sounds being made in the ocean, and they all have a telltale signature. . . . If you start putting in a bunch of external man-made noise, [whales] are going to have a hard time communicating,” Dakin said. It’s like trying to have a conversation with somebody at a rock concert — you have to shout, you can’t hold a conversation for very long and you wouldn’t be able to detect different inflections that you would normally be able to hear.  He has been diving when a big ship has gone by, and “it feels like somebody’s whacking you in the chest with a two-by-four,” he said.

navy listeningBut while scientists are keen to hear what the new undersea recordings have to tell us, the US and Canadian Navies are far less enthusiastic.  They’re concerned that the audio feeds, which are freely available to scientists and the public as downloads and via live online feeds, will reveal sensitive information about submarine and ship movements, navy training activities, and even the sound signatures of individual vessels. The two navies have arranged with researchers to have an audio bypass switch that allows them to divert the audio streams into a secured military computer—sitting in a locked cage at the research facility where the data comes ashore—at times when their ships are nearby (and also at some random other times, so that their diversions don’t give away any secrets on their own!).  This article from The Atlantic dug into the way this system works, along with a quick look at naval concerns about sound from as far back as 1918.  The data diversions from Ocean Networks Canada’s system (often triggered by the US Navy) occur several times a month and last from hours to days. As noted by The Atlantic:

While the Canadian military has yet to return a request for comment, the U.S. Navy reminds me that naval ship movements are classified information, and the fact that those movements might potentially be broadcast on the internet is obviously of concern. “The value of having a cabled system is that it releases data live to the internet,” says U.S. Navy oceanographer Wayne Estabrooks. “But there are some times where we want to protect information, so we have to do diversions.”

“There’s a long tradition of the ocean being the exclusive domain of the militaries and the fishing community, and we’re more or less interlopers in this world,” says [Kim] Juniper, the microbiologist who showed me the photo of the computer in the cage. “The world is changing. . . It’s going to come to a point in the future where this is no longer going to be feasible for the navies to put resources into sorting all this data,” he later says. The hydrophones alone generate 200 gigabytes of raw data each day, and there are other, similar networks of Internet-connected sensors that already exist, or are soon to come online.

Dakin notes, though, that only 4% of the data is lost, and is returned to the science pipeline, often immediately and nearly always within a week.  The military filters out their ship noise, but leaves the rest of the data intact (at least, whatever data is not also in the frequency range of the navy ships or other sensitive sonic activities). “At end of the day, we hardly miss any data at all,” he says.  You can listen to live streams of ONC acoustic data here, and, since that’s rarely very exciting, to a collection of highlights of images and sounds here.

A beautiful new view of humpback whale songs

Animal Communication, Bioacoustics, Ocean 1 Comment »

We’ve all heard that humpback whale songs have complex, repeating structures, and that the themes evolve over course of months and years. Yet listening to the gruts, guffaws, and groans of humpback recordings, it’s hard for most of us to really hear the large-scale structure that ties together these deeply alien sounds. In an article recently published on Medium David Rothenberg and Mike Deal have built on work done back in the 1970s by Scott McVay, and created a visual representation for humpback songs that makes it all suddenly and delightfully clear.

whale song staff WEBFor starters, Deal created glyphs to represent particular “song units.” Each of these distinctive utterances is shown in a different color; the shapes mimic the shape of the sonogram of the sound. Following on McVay’s work with Roger and Katie Payne, Deal and Rothernberg show how these units are combined to create “phrases” lasting 20-40 seconds; several phrases create a “theme,” and a sequence of themes lasting 5-30 minutes is the “song.” Deal and Rothenberg take McVay’s work one step further by overlaying the units on an expanded musical staff to represent the frequqency of each phrase (each utterance of the whales includes a broad range of tones, like a chord with many audible overtones, so the glyphs stretch over a substantial span of the musical staff).

Finally, they present full songs in this new notational language:

1413051978_thumb.jpeg
As Rothenberg notes, “The pattern in the phrases starts to seem like an alien language. But even eerier is how much more human-like the order appears than most known animal vocal behaviors.” Go read the full article; it includes several videos of note, including one that animates the above notation while the 8-minute song is played, and one that explores the compelling similarities between humpback song and mockingbird songs. Also featured are many of the original notations done by McVay, which inspired this new take on it, and exceprts from a recent lecture by Katie Payne (see it here) that dives deep into the questions of cultural change and linguistics that are raised by the extraordinary nature of the these songs.

Scottish study looks at actual vs. predicted impacts on neighbors

Human impacts, Wind turbines 1 Comment »

The Scottish government has commissioned a study addressing an all-too-rarely considered question: do pre-construction impact studies accurately predict the extent of shadow flicker, noise, and visual impacts on nearby neighbors?  ClimateXChange will survey two thousand residents near 10 wind farms, including all residents with in 0.5km, and a sampling of residents at greater distances (somewhat over 30,000 families live within two miles of these wind farms, mostly around two of them).

The steering committee for the study includes at least one concerned citizens group, Scotland Against Spin, along with the leading national trade organizations, Scottish Renewables and Renewable UK, and Scottish Natural Heritage, a quasi-public advisory organization often concerned with landscape impacts. The surveys went out in June and are currently being assessed, with the final report due this winter.

Surprisingly, though ClimateXChange clearly outlines the purpose of the survey as described above, both wind advocates and concerned citizens groups have characterized the study as an investigation into health effects complaints, a topic actually addressed in a previous report (including some in-depth back-and-forth with a prominent critic of their approach and conclusions). ClimateXChange has also completed some other relatively unique reports for the Scottish government, including one on legal compensation frameworks for wind farm disturbance and a look at the long-time informal standard of keeping wind farms 2km from villages (both of these reports are relatively brief and inconclusive, however). A property values study is also currently underway.

NJ sues Feds over academic seismic survey planned for July

Effects of Noise on Wildlife, Ocean, Seismic Surveys Comments Off

The State of New Jersey has gone to federal court to block a seismic survey planned for this month fifteen miles offshore.  The survey, funded by the National Science Foundation, received its final permits from the National Marine Fisheries Service last week; the permit (similar to those issued routinely for oil and gas exploration or Navy sonar training) allows the sound from the airguns to incidentally harass marine mammals, including the possibility of some permanent injuries.  The New Jersey Department of Environmental Protection is aiming to stop the surveys from commencing in the next week or so; they claim that this is a poor time of year to introduce potentially harmful or harassing sounds, that the surveys could disrupt local fisheries for scallop, flounder, and squid, and that the National Science Foundation should have undertaken a more comprehensive public comment and environmental assessment process.

UPDATE, 8/14/14: Mechanical issues have sidelined the survey for this summer; the National Science Foundation plans to carry out the survey next year instead, while local activists vow to push for more thorough analysis and public input.

LangsethWEBThe survey, by Columbia University’s research vessel the Marcus Langseth (left) would examine seafloor sediment, as part of research looking at how climate change has affected river runoff and deposition over the past sixty million years.  Some critics, though, seem to be conflating the purpose here with a broader initiative underway to open Atlantic waters for new seismic surveys exploring for oil and gas; those plans have stirred controversy in states up and down the eastern seaboard.

“We believe the timing of this program will be detrimental to various marine species that migrate and breed off the New Jersey coast and will negatively impact the commercial fishing industry that relies heavily on these resources,” said New Jersey DEP commissioner Bob Martin.  Similarly, Bob Schoelkopf of the Marine Mammal Stranding Center in Brigantine, was quoted as saying: “Right now, bottlenose dolphins are mating and giving birth off the coast of New Jersey. May and June are the birthing periods. They are totally dependent on their parents to provide nursing for the first two to four years of their life, and if the mother, for some reason, cannot catch fish to eat, she can’t produce milk.”  It’s not obvious from these statements whether there is another time of year that either would suggest for a survey such as this.

Meanwhile, the Asbury Park Press spoke to the project’s lead scientist, Rutgers geology professor Greg Mountain, likens the technology to medical sonograms, and says it will cap years of investigations using sea floor corings to recover ancient sediment. The goal is to understand climate and sea level changes over millions of years, information that will be critical to foreseeing future sea level change along the East Coast, Mountain says.

[Click through for more info on seismic surveys in general, and AEI’s quick take on this situation]

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Airguns infect summer soundscapes in remote polar Atlantic Ocean

Effects of Noise on Wildlife, Ocean, Ocean energy, Seismic Surveys Comments Off

AEI lay summary of:
Holger Klinck, Sharon L. Nieukirk, David K. Mellinger, Karolin Klinck, Haruyoshi Matsumoto, and Robert P. Dziak. Seasonal presence of cetaceans and ambient noise levels in polar waters of the North Atlantic. J. Acoust. Soc. Am. EL176, 132 (3), September 2012.

I somehow missed this study when it was published a couple years ago, but the findings are so striking that I can’t resist turning back the clock to cover it.  Researchers from Oregon State University and NOAA’s Pacific Marine Environmental Laboratory analyzed data from two hydrophones deployed for a year in some of the most remote areas of the very northern Atlantic Ocean, and found seismic survey airgun sounds to be a dominant presence, audible for 95% of each day for five months a year (and over half the hours for two more months).

Klinck map and 3 spect350Luckily for the fin whales who are the most populous marine mammal in these remote waters east of northern Greenland, they tend to show up toward the end of the summer airgun season, and concentrate their polar activity in the winter, when the airguns go silent.  But blue whales and a relatively few sperm whales like to be there in late summer, and must co-exist with the steady rumble of airgun sounds, which increase the ambient sound levels by an average of 5-10dB, and up to 20dB.  By contrast, the roar of storm-driven winter waves adds up to 12dB, and the calls of thousands of fin whales add up to 10dB.

The authors don’t speculate about the location of the seismic surveys being heard in the region, which lies well north of the Arctic Circle (the two sites are between 75 and 80 degrees north latitude; the Arctic Circle is at 66.5).  But it’s a straight, if rather long, shot from the North Sea oil fields between the UK and Scandinavia, with Norway’s offshore arctic developments a bit closer. I suspect that the offshore concentrations of red between Norway and the study sites are likely active oil fields, with heightened airgun activity; the dark red North Sea hosts one of the world’s highest concentrations of ongoing seismic surveys.

Shipping global graphic WEB Polar Atlantic CROP copy

What’s especially discouraging about these findings is that this is one of the increasingly rare parts of the world’s oceans that is largely spared the scourge of shipping noise.  The more northern site lies close to a minor shipping lane between Norway and its remote arctic island outposts, but compared to the din of ships in most of the temperate latitudes (where shipping noise has roughly doubled in intensity each decade since the 1950s), this should be—or couldbe an acoustic refuge. The map to the right shows the study areas, on the sparse fringes of the red cloud of global shipping routes. (Ed. note: Fish, which are not as wide-ranging as whales, and often use low-frequency sounds, are also likely affected by the increased background noise caused by airguns.)

The whales who visit seasonally seem to be putting up with the additional noise from seismic surveys; hundreds of blue whales are heard during 60-80% of hours in August and September, even as airguns continue to be heard nearly 100% of hours; the newly-arriving fin whales are heard close to half the time in those months, increasing to 70-80% of hours as their numbers climb to an estimated 6000 in mid-winter. Of course, at close range the whale calls are much louder than the distant airguns; but the steady hum of airguns at 5-10dB above what would otherwise be the background sound level can make it difficult for whales to hear their brethren across the dozens or hundreds of miles that they might otherwise communicate. As the authors note: “(D)uring the summer months. . . reverberation effects associated with the propagation of airgun signals often caused a continuous series of transient sounds.” 

The authors note that recordings made in the early 1970s show winter-time sound levels similar to those recorded in this study; that study, however, did not find the summertime increase that is now associated with the distant seismic surveys.

Navy (mostly) prevails in LFA lawsuit

Effects of Noise on Wildlife, Ocean, Sonar Comments Off

Eighteen months after a lawsuit challenged the latest 5-year authorization for the US Navy’s SURTASS-LFA low-frequency active sonar system, Federal Judge Elizabeth Laporte ruled in the Navy’s favor on nearly all counts.  And last week, the Navy agreed to do a Supplemental Environmental Impact statement that will address the key point on which she found in favor of the plaintiffs.

As reported here earlier, the Navy was authorized to deploy LFA sonar on four ships, though initially only two were so equipped, both generally deployed in the western Pacific, monitoring North Korean and Chinese vessels (in 2009, their presence spurred a multi-month spat with China). The legal challenge addressed here, filed in late 2012 by the NRDC and several allies, targeted both the Navy’s EIS and the National Marine Fisheries Service’s five-year incidental take regulations.  In her ruling last March, Judge Laporte sided with the Navy and NMFS on most counts.  Most centrally, Judge Laporte ruled that the relatively limited set of Offshore Biologically Important Areas (OBIAs) that should be avoided by LFA sonar was justified by the science, and was not, to use the legal-standard terms, arbitrary and capricious (by contrast, NRDC charged that the 22 OBIAs were “literally a drop in a bucket” within the 50% of the earth’s oceans open to LFAS deployment). In addition, several specific ways in which the Navy and NMFS limited OBIA protections were ruled valid, including using only seasonal OBIAs to protect sperm whales, and omitting harbor porpoises and beaked whales from OBIA protections because the sonar’s frequencies do not overlap their hearing ranges.  And, in several areas, Laporte also rejected claims that the Navy failed to use the most recent available evidence (this is a new angle of attack, one that Laporte showed some openness to in a related suit on the Navy’s mid-frequency active sonar plans).  In addition, she ruled that the Navy and NMFS did not fail to consider alternatives to LFAS, and did not fail to “take a hard look” at effects on non-marine-mammal species such as fish.

However, in one area, Laporte found that the Navy’s EIS fell short: it failed to update its stock estimates for bottlenose dolphins around Hawaii based on a new study (released after the initial impact assessments were done, but before completion of the final EIS) that showed more bottlenose dolphins in waters around Hawaii than previously estimated (two exercises with the Pacific LFA ships occur near Hawaii).  Thus, the Navy’s impact estimates, using the old numbers, are too low.  In a final agreement approved by Laporte in late May, the Navy agreed to re-run its estimates in a Supplemental Environmental Impact Statement, to be completed by February 2015; if past is prologue, the Navy will run its new numbers and find that the impact is still negligible.  However, the LFA plan aims to impact no more than 12% of any regional stock of each species, and it may not yet be clear whether the new numbers will push impacts above that threshold (the earlier estimates peaked at 6% of the stock of Hawaiian bottlenose dolphins in offshore pelagic waters). 

If that’s not enough legal reporting for ya, then click over to this post from January 2014 detailing the most recent round of lawsuits, filed against new 5-year permits for Navy training areas in US offshore waters.

IMO adopts shipping noise guidelines, adding to ISO measurement standards

Effects of Noise on Wildlife, Ocean, shipping Comments Off

The International Maritime Organization (IMO) has adopted the first-ever comprehensive guidelines on shipping noise.  The voluntary guidelines mark the first step toward a longer-term goal of bringing noise factors into planning for both ship design and shipping routes.

ShippingContainerSFBay 250This marks the successful completion of a six-year process, largely spearheaded by NOAA, the US Coast Guard, and their German counterparts at IMO. The US Chamber of Shipping, a trade organization, has also been engaged from the start.  While the guidelines are voluntary, leading some observers to question their value, it is expected that many key players will begin to work with the guidelines in coming years. In general, the shipping industry is far more willing to design new ships to be quieter, than to retrofit older ships. Ed. note: one fascinating insight from the early IMO process was that global shipping noise may be dominated by relatively few unusually loud ships in each size class. 

PacNoise475

In this ocean noise map created by NOAA, the darkest areas represent noise about 60dB above natural ambient levels

As summarized by NRDC, the new guidelines mark a milestone in ocean noise awareness on several fronts, as they:

  • recognize that shipping noise can have short-term and long-term impacts on marine life, especially on marine mammals;
  • call for measurement of shipping noise according to objective, available international standards;
  • identify computational models for determining effective quieting measures;
  • provide guidance for designing quieter ships and for reducing noise from existing ships, especially by minimizing the roar produced by ship propellers, in a process known as cavitation; and
  • advise owners and operators on how to minimize noise through ship operations and maintenance, such as by polishing ship propellers to remove fouling and surface roughness.

UPDATE, 6/4/14: In 2012, the International Organization for Standardization (ISO) developed formal standards for the measurement of underwater sound from ships.  ISO standards provide detailed specifications that assure consistency in what is being measured (frequencies, reporting metrics), and how (distance from sound source, conditions, etc.).  Combined with the IMO guidelines, shipping companies now have the tools they need to provide clear information on the noise footprint of their vessels and the design choices they make to reduce noise; although neither the IMO nor ISO specify specific limits or targets for ship noise, they provide standardized ways of reporting on the noise of ships.  RINA Services, which provides a wide range of independent marine certifications, has just added a new voluntary notation, DOLPHIN, that combines the IMO and ISO reporting standards, and gives shipowners a third-party certification option to specify commercial vessels which have implemented solutions to minimize radiated underwater noise.

Fantastic ocean noise presentation from Leila Hatch of NOAA

Bioacoustics, Effects of Noise on Wildlife, Human impacts, Ocean, Science Comments Off

Earlier this month, Leila Hatch, one of NOAA’s leading experts on ocean acoustics and a long-time researcher in and around Stellwagen Bank National Marine Sanctuary, presented an hour-long talk on ocean noise.  It’s been archived on the Open Channels website, and is available for streaming and download on Vimeo.  

It’s by far the best introduction I’ve seen to this wide-ranging topic, including some basic information on ocean noise, along with a good summary of ongoing work at NOAA to map ocean noise and to learn more about how shipping noise, in particular, can impinge on whales’ communication space. Highly recommended!!

Listening to our Sanctuaries: Understanding and Reducing the Impacts of Underwater Noise in Marine Protected Areas from OpenChannels on Vimeo.

Deepwater Wind agrees to limit activities to protect Right whales

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Deepwater Wind, which recently won the first-ever competitive lease auction for US offshore wind, has signed an agreement with a consortium of environmental organizations that affirms its intention to minimize potential impacts on critically endangered Right whales. The wind farm’s location, in Rhode Island Sound, is host to foraging Right whales each spring; the agreement delays any pile-driving activity until after May 1, when whales have generally moved north.  In addition, pile driving later in the year will take place only during the day, when any lingering whales can be more easily seen.

Deepwater2 WEB

The agreement marks an important step forward in marine conservation, with wind energy developers agreeing to key provisions that the Navy and oil and gas exploration companies have resisted: changing their operational schedule to avoid times of particular biological importance in a given area, and agreeing to limit loud noise-making activities to daylight hours.

The current agreement covers pre-construction activities, including pile-driving five foundations, for meteorological towers and perhaps test turbines (the press release does not specify). The Deepwater ONE wind farm will ultimately be home to 150-200 turbines; construction of that phase of the project will create a significant noise footprint, and we will hope that the company agrees to continued protective conditions at that time. A similar agreement by Deepwater for its smaller 5-turbine Block Island Wind Farm does cover the actual construction period; that press release does not mention daylight-only construction, but does delay construction until May. However, a broader agreement between environmental groups and several wind developers does include a provision precluding pile driving at night or in heavy fog; one hopes that this good-faith agreement will indeed be reflected in actual final operational plans. 

NATO sonar exercises, strandings in Crete

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While recent years have seen an apparent reduction in the number of sonar-related strandings, one of the world’s hot spots for such tragedies saw a rash of strandings in recent days.  Two different stranding events occurred along the southern shore of Crete, the first involving 5-7 Cuvier’s beaked whales along a 16km stretch of coast, and the second occurring a few days later and 48km east, where three members of the same species came ashore.  In both cases, many of the animals were refloated and returned to sea (and unknown fates), while four whales died, including a fetus that was apparently close to term.

CRETE web

 

A NATO naval exercise, Operation Noble Dina, is ongoing in the area, involving US, Greek and Israeli forces. This part of the Mediterranean has been the site of several previous strandings, as noted by NRDC’s Michael Jasney:

For Greece, none of this is new. In 1996 and again in 1997, dozens of beaked whales of the same species turned up along the Peloponnesian coast; in 2011, they stranded on the island of Corfu as well as the east coast of Italy, across the Ionian Sea. In each case, navies were training with high-powered sonar in the area. Indeed, according to the Smithsonian Institution and International Whaling Commission, every multi-species beaked-whale mass stranding on record everywhere in the world has occurred with naval activities, usually sonar exercises, taking place in the vicinity.

One of the ongoing areas of contention between environmental advocates and the US Navy and federal regulators is whether sonar training (and naval live-fire and explosion exercises creating loud and potentially harmful noise) should be planned to avoid areas with known concentrations of marine mammals, especially those, such as beaked whales, that are especially sensitive to noise.  As it turns out, the area of this stranding is one of a large number of areas recommended as Areas of Special Concern for beaked whales by that the Scientific Committee of ACCOBAMS (Agreement for the Conservation of Cetaceans of the Black and Mediterranean Seas, a consortium of governments in the region).  As reported by a long-time chair of its Scientific Committee, the recommendation fell on deaf ears when presented to the full ACCOBAMS meeting of the parties last year; military preparedness was the explicit reason for the rejection.

In the wake of the two stranding events, Operation Noble Dina continues, but was moved 100km south of Crete—now outside the boundary of the proposed Area of Special Concern, yet apparently still able to complete its military preparedness mission.

FAA adds insult to injury with new Grand Canyon flight permits

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Eighteen months after Senators John McCain (R-AZ) and Harry Reid (D-NV) joined forces to undermine the National Park Service’s Grand Canyon air tour management plan just before it was set to go into effect, the Federal Aviation Administration apparently feels that the discounted per-flight fee for quiet aircraft is not incentive enough to encourage the air tour industry to invest in new-generation planes. Rather, the FAA has decided that the best way to do so is to allow 1721 additional flights to the annual parade of planes piercing the skies over the Grand Canyon, so long as these new flights utilize “quiet” aircraft.

Grand Canyon view from air tour500

 

“The so-called quiet technology is not quiet,” said Sandy Bahr, director of the Sierra Club’s Grand Canyon Chapter. “It’s less noisy, but it’s not quiet.” Flagstaff resident Jim McCarthy, who did a master’s thesis at Arizona State University on noise pollution in the Grand Canyon, said air tour companies are “gaming the park.” Because the quiet technology is defined by noise per seat, aircraft can be noisier as long as they hold more people, he said. “It can be completely counterproductive.” (above image is the view from an air tour)

A park spokesperson notes that the additional flights only add about 3% to the flights already occurring; at peak times, planes take off every 90 seconds, heading for the two most popular air tour corridors.  As with snowmobiles in Yellowstone, the annual cap on allowed flights is far higher than the number of flights that have been occurring in recent years: the FAA authorized about 90,000 flights in 2012, the most recent year for which numbers were available, though only (!) 55,185 commercial air tours were actually flown that year.

See earlier AEI coverage of this fiasco here

Oregon project aims for floating offshore turbine future

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After nearly five years of floating offshore wind farm planning off the coast of Maine, a project in Oregon may leapfrog those efforts.  An initial go-ahead from federal ocean regulators marks the starting line for a pilot project off Coos Bay, which will need to clear several more regulatory and financial hurdles before being built.  

Perhaps optimistically, Principle Power (the developer) is holding a target date of 2017 to have its initial five turbines operational.  These will be huge, 6MW, 600-foot turbines, similar in design to a model that’s already being tested in the water in Portugal.  The project is expected to cost $200 million, which would build around 100MW of capacity on land, as compared to the 30MW this pilot project will construct; Principle Power expects that steadier, stronger offshore winds will let these turbines operate at a higher capacity factor than onshore projects, partially making up that difference. Of course, experimental pilot projects are always far more expensive than later, full-scale build-outs; still, the financial feasibility of projects like this is a work in progress.

Virginia offshore wind developer agrees to avoid right whales for evaluation, but not for construction

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Last fall, Dominion Virginia Power won the first federal lease for developing wind power off the coast of Virginia.  As with all offshore energy and Naval activity on the east coast, one of the first environmental concerns to be raised was what measures would be taken to minimize impact on the critically endangered North Atlantic Right whale. While their population has been more or less steadily rising since 1990, with only about 400 individuals, they remain vulnerable to any negative impacts, from ship strikes to increased stress levels, which may reduce reproductive rates and success. (See NOAA’s most recent stock assessment report for details; it notes lower reproductive rates than other Right whale stocks, and concludes that the population will be negatively affected if it loses more than 0.9 whales per year to human impact.)

Turbine being boated offshoreWith all this in mind, Dominion Virginia Power’s first commitments to the Virginia Offshore Wind Development Authority fell far short of what many had hoped.  The company agreed to limit installation activity of test platforms (meteorological towers and preliminary test turbines) during the period when whales are most apt to be migrating past the Virginia coast, but made no such commitments about later, and much more extensive, pile-driving for hundreds of turbines in the eventual wind farm.

“We’re happy to talk” with environmental groups, said Mary C. Doswell, Dominion Resources Inc.’s senior vice president for alternative energy solutions, though she noted, “we can’t overlook the costs of compliance.”

The company said they’d minimize their first-phase activities from late November to late March.  The whales spend the summers in a large area off the coast of New England and the Canadian Maritimes, and concentrate at birthing grounds off the coast of northern Florida in winter. NOAA maintains a reduced speed zone along the mid-Atlantic coast, to protect migrating Right whales, from Nov.1 to April 30, close to two months longer than the company set aside as their cautionary season; even the speed restriction is seen by some as a potential obstacle to offshore wind data collection.

UPDATE: See also this article from last fall, which suggests that Dominion plans only to erect a 2-turbine test platform, with full-scae development of 200 or more turbines on hold until costs come down for offshore wind construction.  Some wind advocates suggest that Dominion, which has fought renewable energy initiatives in the state, secured the lease largely to prevent others from developing a large offshore capacity.

Vermont PSB asking for input on turbine noise standards

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The state Public Service Board has initiated a public process for re-examining the noise standards used at wind and natural gas energy facilities in Vermont.  Geoff Commons, the PSB’s public advocate, notes that neighbor complaints from wind projects operating in compliance with a 45dB standard are part of the driver for this review.

VT SheffieldWEB“Even with these restrictions placed on several recently constructed facilities, the board has received complaints regarding sounds produced by the operation of some facilities. These complaints have raised questions about whether the limitations that the board has previously adopted are adequate,” the PSB stated in December.  “As a result, the board has determined that it is appropriate to commence a general investigation into the issue of appropriate sound standards for facilities that are subject to the board’s jurisdiction.”

The PSB has established a website to track this process.  A pre-hearing conference was held on January 8, and based on discussions there, a scoping document outlining initial ideas about procedures and key questions for the process have were released on January 29, and can be downloaded here.  Public comments are being accepted through March 3, after which the final scope of the process will be determined, followed by a series of public workshops to address specific issues.  The outcome of this process will be a determination as to whether a new set of binding sound-related standards is needed; if so, that will occur during a separate formal process.

From my first reading of the preliminary scoping document, it appears that the focus may be strongly oriented toward health effects, and the standard effort to determine “state of the art” scientific information; the initial list of questions doesn’t appear to consider quality of life impacts.  However, the final scope may change, based on comments during this scoping phase.

Legal challenges mount to new round of Navy training permits

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In December, the Navy’s current five-year plan for training and testing activities around Hawaii and off the southern California coast were approved by NOAA regulators, covering the years 2014-2018.  The approval authorized incidental takes of marine mammals, including both widespread behavioral changes and close-range injuries and some deaths, as a result of sound exposure from sonar and explosives, as well as ship strikes.

ShoupImmediately after NOAA’s approval, environmental organizations filed suit in federal court in Hawaii, and this week, other organizations filed suit in a San Francisco federal court (the Navy pushed back in a brief statement).  It’s unclear from early press coverage how much overlap there is between the two; the Hawaii suit, led by Earthjustice, initially named just NOAA, but has been amended to also name the Navy as a defendant.  The San Francisco suit, led by the NRDC, targets NOAA, charging that federal regulators did not use “best available science” and that their finding of “negligible impact” violates the Marine Mammal Protection Act.

At issue in both suits is the shockingly large numbers of animals that are permitted to be affected, amounting to nearly 10 million behavioral responses, the potential for 2000 permanent injuries (including hearing impairment), and 155 deaths over the course of five years.  “This is an unprecedented level of harm,” Zak Smith, an attorney with the Natural Resources Defense Council, said. “In order to authorize these impacts on marine mammals, the service had to turn its back on the best available science.”

It’s important to note that while sonar has been the focus of most public concern, explosions during testing and training are predicted to cause most of the injuries and deaths.  The Navy and NMFS consider the estimates to be extremely cautious (ie far higher than actual likely impacts) for a number of reasons; see the bullet list in this earlier AEI post for more on why.

NRDC, Earthjustice, and the other plaintiffs continue to stress that the Navy can and should limit its activities in areas and times of particular biological importance to marine species; the lack of such “spatio-temporal restrictions” has been a bone of contention for many years, and this time, as in past rounds of permitting, the Navy and NMFS determined that such restrictions would yield little biological benefit.  A largely similar lawsuit filed in 2012, challenging NOAA permits for Navy training in the Pacific Northwest, ended up in a split decision, with the “best available science” ruling going against NOAA, but the large takes challenge (including the lack of exclusion zones, as well as faulty negligible impact ruling) falling short, with the court approving of NOAA’s analysis and actions.

UPDATE, 2/10/14: See this article from NRDC, outlining their reasons for this lawsuit and how it fits in with their 20-year history of focusing on ocean noise issues.

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23 Texas wind farm hosts sue over noise, nuisance

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In what may be an unprecedented move, 23 Texans who host wind turbines on their property have filed suit against two different wind farm developers, claiming that companies “carelessly and negligently failed to adequately disclose the true nature and effects that the wind turbines would have on the community, including the plaintiffs’ homes.”

The plaintiffs host hundreds of turbines on projects developed by Duke Energy and E.ON, and as a Duke spokesman noted, they did consent to the placement of the turbines.  However, the lawsuit stresses that the companies told residents the turbines “would not be noisy, would not adversely impact neighboring houses and there would not be any potential health risk.”  

This court challenge stands apart from most previous nuisance suits, nearly all of which been filed by non-participating neighbors of wind farms (ie, local residents who are not hosting turbines themselves).  Most annoyance surveys suggest that wind farm hosts are less likely to be bothered by turbine noise than non-participating neighbors, and many wind projects make an effort to spread the financial benefits to include some non-host neighbors, because of suggestions that broader project participation will increase community acceptance.  In this case, however, the plaintiffs are receiving lease payments and tax benefits that will exceed $50 million over the life of the projects.

Among the plaintiffs are Willacy County Commissioner Noe Loya, who is said to “no longer enjoy sitting outside because of the loud noise,” with turbine noise inside and outside his home “disturbing the peace and making it difficult to enjoy living there.”  Another plaintiff, a local Justice of the Peace, “has difficulty sleeping, cannot have his windows open (and) cannot enjoy the sound of nature, due to loud noise from wind turbines.”  The lawsuit also claims that some residents have abandoned their homes. In addition to noise issues, the suit includes visual impact, property value, and health effects claims.

E.ON spokesman Elon Hasson, says the company is reviewing the suit. “We develop all of our wind farms in a safe, state-of-the-art and responsible manner. . . We believe these claims will be shown to have no validity.” 
UPDATE, 1/31/14: Spokesmen from both companies issued statements noting that one claim of the suit—that the companies had no plans to remove the turbines at the end of their useful life—is false, and stressed their ongoing monitoring and maintenance of the machines.  They more generally dismissed the other accusations, as well. 

The suit was filed in State District Court in November.  In December, the companies requested that it be moved to federal court, where U.S. District Judge Hilda Tagle has called for a response from the companies by February 6.  

Ed. note: Some wind development leases I’ve seen explicitly preclude hosts from filing nuisance suits. There is limited information online about this case, and it’s unclear whether the plaintiffs’ contracts include such restrictions; if they do, then the legal case may be open-and-shut, or it may be that the crux of the legal challenge is the veracity and completeness of information provided to hosts prior to signing contracts. (It may be worth noting that lease agreements don’t usually include “gag clauses” against speaking publicly about noise or other post-construction experiences; confidentiality clauses usually cover only financial terms and development plans.)

New research listening in on whales as they hunt

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Two new research projects are taking important next steps in understanding the importance of sound, and clear listening, to whales.  In recent years, ocean bioacousticians have introduced the concept of “communication space” or “effective listening area” to scientific parlance. This began as a conceptual framework for thinking about how human sounds (especially shipping noise) may reduce the area across which whales can hear and be heard; researchers are now digging into more of the details of how this may actually impact animals in their daily lives.  After several recent studies that focused on whales hearing each other (and so framing their results in terms of “communication space”), two new studies are gathering initial data that may inform considerations of the ways whales listen for the presence of prey.  While whales can, and do, change some of their communication signals or patterns in order to be better heard by other whales in noisy conditions, there’s no such compensation that can help a whale hear their prey through a wash of noise.

Both of the new studies are taking advantage of acoustic tags to allow scientists to listen in on whales as they are foraging.  These tags are about the size of a large cell phone, and are attached to the animals with suction cups; they remain attached for up to 16 hours, then float to the surface for retrieval.  While attached, they record all sounds the whales hear and make, as well as logging swimming speed and dive orientation.

Orca attack seal near shoreWEBOne study is further along, having just published its first results, which confirm that orcas can hunt in near-total darkness, apparently relying only on zeroing in on their prey (in this case, seals) by listening for their mating calls.  These orcas do not use echolocation while hunting (other orcas, hunting salmon, do echolocate); they hunt in stealth mode, then dispatch their victims with a swat of their tail flukes.  This initial evidence is not totally conclusive; followup studies will confirm that orcas do, indeed, seek out seal sounds.  And, this sort of study is but the first step toward quantifying the extent to which ocean noise may limit the range over which orcas can hear seals while hunting.

The second study will begin next year, and will be putting the acoustic tags on large whales, to see whether they’re using acoustic cues to help locate aggregations of fish.  According to Dr. Rochelle Constantine:

“Acoustics within the marine space are really important for many organisms, yet we don’t know a lot about how it drives organisms’ interaction with their environment. We’re interested in looking at how the larger animals use the acoustic environment, particularly for food, and testing the hypothesis that food patches have specific sound signatures.”

Lunging Brydes Wha 300WEBShe said the sound of “bait balls” of prey, such as schools of fish, could be greatly heightened when a feeding frenzy involving larger fish and seabirds broke out.  Dr Constantine said whales had been observed swimming rapidly from over a kilometre away toward prey aggregations, “so we’re very interested to find out if there are specific acoustic cues they home in on”.

This study plans to play recorded sounds of fish aggregations and other prey sounds while the tags on the whales.  (I suppose if they happen to get lucky and have an actual feeding event occur while tags are attached, that will be a bonus, but the playback will serve as a reliable testing condition.)  This team is also interested in using acoustic tags on large fish and sharks, to explore the ways they may rely on listening, as well.

New paper details the acoustic quality of critical whale habitats

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AEI lay summary of:
R. Williams, C.W. Clark, D. Ponirakis, and E. Ashe.  Acoustic quality of critical habitats for three threatened whale populations.  Animal Conservation (2013).

Innovative research along the coast of British Columbia has quantified the degree to which shipping noise is reducing the distance at which whale vocalizations can be heard.  This is one of the first studies to use recordings of actual ocean noise levels to examine how the “communication space” of whales is affected by shipping noise in an area where whale conservation is a priority.  Among its troubling findings is that endangered orcas are facing the highest levels of noise in areas that are legally designated as critical habitat, with communication space reduced to 25% or less even in average noise conditions; over the entire study region, the area over which orcas can hear each other can be reduced by 62% during average noisy conditions, and 97% during the noisiest times.  Humpback whales face nearly as large reductions in some key areas (though not formally designated critical habitat; and, notably, are showing signs of a tenuous recovery in some of the areas studied), while fin whales, who have louder calls than the other species, are only mildly affected by shipping noise.

WilliamsCROP(noise levels and communication space in median noise conditions)

Communication space (alternatively termed “effective listening area”) is a relatively recent introduction into scientific parlance; it’s a measure of the area within which a particular species can hear and be heard by others of its kind; both marine and terrestrial bioacousticians have begun using this framework to better understand the ways animals may be affected by increased background noise introduced by human activities, including shipping, roads, and airplane overflights.  Previously, small increases in background noise were commonly considered to cause only negligible impacts, since there is rarely a clear or consistent behavioral reaction.  However, many animals rely on hearing things at the edges of audibility (calls of their kin, the approach of predators, the presence of prey), and a significant reduction in an animal’s communication space can cause a need to use more energy hunting, or to be in a heightened state of alertness (and stress) to avoid predation.

 

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Ocean noise may disrupt larval development

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AEI lay summary of:
Natasha Aguilar de Soto, Natali Delorme, John Atkins, Sunkita Howard, James Williams, Mark Johnson.  Anthropogenic noise causes body malformations and delays development in marine larvae.  Nature Scientific Reports, 3:2831.  DOI: 10.1038/srep02831 Download PDF

Just months after shipping noise was shown to cause dramatic behavioral changes in crabs, this new paper provides the first evidence that low-frequency seismic airgun sounds may trigger developmental delays and malformation in the larvae of shellfish.  Over the past decade or so, as researchers have looked more closely at behavioral disruptions caused by human noise sources, including temporary displacement of some fish stocks away from seismic surveys, there has been some concern that acute noise exposure from high-intensity sound sources such as airguns could also affect larval development.  If this were shown to be so, then regulators may need to consider protecting some vulnerable areas from intense noise exposure during seasons of key larval development.

This study exposed scallop larvae to recorded sounds of airgus, and compared larval development beginning after 24 hours of sound exposure and continuing until 90 hours.  This encompassed several stages of larval development, with 470-800 larvae examined at each sampling time.  

AirgunsLarvae350For the first day and a half, larvae exposed to airgun noise showed significant developmental delays.  At close to two days, the noise-exposed group appeared to be nearly as likely to be fully developed as the control group (upper right chart).  But, after passing the 48-hour mark, as the larvae moved into the next stage of development, those in noise lagged again; at 66 hours, all of the control larvae had completed the D-veligar development, while a large proportion of those exposed to noise did not complete this transition.  In addition, a significant proportion of the noise-exposed larvae began exhibiting physical abnormalities (localized bulges in the soft body of the larvae, but not in the shell).  By the end of the study, at 90 hours, an average of 46% of noise-exposed larvae showed malformations, ranging from 27%-91% in the four flasks being independently analyzed. (Ed. Note: I’ve reproduced five of the seven charts here, omitting samplings at 54hrs and 90hrs for the sake of better readability.)

The authors note that “the abnormalities observed here are comparable to those caused by chemical pollutants or water acidification, which have a clear impact on larval survival.”  They suggest several possible mechanisms for the abnormal bulges observed, and conclude that “although the exact mechanism is far from evident, physiological stress is likely the mediator for the developmental delays and growth abnormalities reported here.”  Further, the authors note that while behavioral responses vary widely both among and within species, stress response mechanisms are more generally similar across taxa, “suggesting that other invertebrates with similar growth patterns may be similarly affected.”

Of course, the nature of sound exposures in the ocean will be markedly different than those in this laboratory experiment, in which larvae were repeatedly exposed to a steady stream of 160dBrms impulses, once every three seconds for 24-90 hours.  In particular, the authors suggest that particle motion, rather than sound pressure, is the likely trigger for the effects, and acknowledge that several factors make it difficult to accurately predict the impact zone around an airgun in which particle motion would approach the 4-6mm/s RMS experienced by the sound-exposed larvae here.  In addition, the long periods of continuous exposure used in this testing procedure, while necessary in order to determine if there were indeed clear dose-response effects, may not be widely replicated in the wild.  Accordingly, the authors recommend that future research aim to establish the thresholds of exposure levels and durations that cause the effects seen here.

However, the authors stress that “given the strong disruption of larval development reported here, weaker but still significant effects can be expected at lower exposure levels and shorter exposure durations, especially if some ontogenetic stages such as the D-veliger prove to be particularly sensitive.”

Aussie wind farms moving forward with 2km setbacks

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Despite much gnashing of teeth among wind developers and some wind advocates, it appears that the Australian wind industry is adjusting to larger setback requirements.  In the past two months, two large wind farms have cleared key approval hurdles in New South Wales, with both incorporating the 2km setback requirement from non-participating homes that is included in draft NSW wind planning guidelines.

The 33-turbine Bodangora Wind Project received approval from the NSW Planning Assessment Commission in late August, which noted that while “noise emissions from the turbines will be audible from some surrounding dwellings,” sound models suggest that sound at non-participating neighbors will be 30dBA or less (and 52dBC or less), noting that “the 2km buffer provided in this instance is highly precautionary.”

CollectorMeanwhile, the 63-turbine Collector Wind Farm has been received a recommendation for approval by the NSW Department of Planning this week, and now awaits final approval from the Planning Assessment Commission.  Despite the recommendation, Tony Hodgson of Friends of Collector said strong opposition remained in the community, which would be enthusiastically voiced at a community meeting with the PAC at the end of October. “We spent a lot of time and a lot of energy putting in our submission, and nobody from the department ever talked to us,” Mr Hodgson said. “We feel very, very hard done by. We think it’s an outrage, and the whole thing’s been a complete waste of our time.”  The Collector project includes one home just inside the 2km buffer, and a couple more just outside it, as seen on the most recent site map (above; yellow line is 2km; red turbine sites have been removed). The project’s Sound Assessment found that the three closest non-participating homes would remain just under the 35dBA noise limit (10-minute average), as well being well below the 60dBC limit.

The NSW Draft Planning Guidelines, which were released in December 2011 and have yet to be finalized, included a requirement that projects receive permission from all homeowners within 2km.  NSW’s southern neighbor Victoria has been operating under a 2km setback requirement for two years now; over 20 wind projects are in the planning stages, with one in the midst of the approval process.  NSW’s other neighbors, South Australia and Queensland, are also charting cautionary paths, though without absolute 2km limits on the table so far (both have 35dBA noise limits, which generally requires setbacks of 1.5km or more).  As in Australia, the US state of Oregon appears to have a robust wind development environment, despite the widespread use of a 36dBA noise limit, which similarly pushes turbines significantly further away from neighboring homes than is typical in much of the US and Canada.

Sandia workshop highlights new understanding of turbulence in wind farms

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A long, detailed article in Windpower Engineering provides a fascinating look at current efforts to understand the complex wind flows in and around wind farms.  Recent research at NREL, Sandia National Laboratory, and Texas Tech is highlighted in the article, which also includes several compelling graphic representations of the patterns of turbine wakes inside wind farms.  For the first time, researchers are now able to measure wind speed and direction in three dimensions in working wind farms, using multiple dopplar radar units; this data has led to new and far more detailed computer models that can be used to investigate how small changes in turbine operations may reduce stresses on downwind turbines.

Read the whole thing at the link above; here are a few teasers:

“It’s almost as if we added a dye into the wind that changes color with speed,” says Moriarty, commenting on the video he presented. “The images show high winds in red or hot colors, and slower winds speeds in blue, and how well downstream turbines are working.

What has been known for a while, he says, is that under certain atmospheric conditions, turbines are getting beat up by what’s called a mildly stable atmosphere. “Even though this has been known for a while, we don’t know exactly what is happening in the flow that influences damage events” says Moriarty.

Although tuning a wind plant is difficult, Moriarty’s simulations suggest adjustments. “We have run several simulations, for example, that de-rate (reduce the power) the first row to let more energy through. That works under some conditions. And then there’s wake steering, moving a wake. Changing the yaw on one or more turbines allows controlling where the wake flows, ideally away from downstream turbines. Depending on yaw angle, results show a 4.5% increase in energy capture.”

UPDATE, 10/17/13: Here’s more on turbulence research, this time in India, where the Tamil Nadu province has some insane turbine densities (check out the image at the link; note the 2km bar at the bottom right).