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Acoustic monitoring increases in US northeast waters

Bioacoustics, Ocean, Science No Comments »

Several independent research projects that are listening to fish and whales in waters along the coast from New Jersey to Maine have joined together as the NorthEast Passive Acoustic sensing Network (NEPAN).  This map shows the location of the various research programs that will be taking place through 2017:

NEPAN_labels_MT

The NEPAN website offers a good overview of the aims of each of these projects.  Of particular interest is a real-time buoy deployed near a Coast Guard gunnery range off Rhode Island, which will help the Coast Guard to avoid initiating live-explosive exercises when any of the few remaining critically endangered North Atlantic right whales are in the area.  The array of long-term recorders along the edge of the continental shelf will also provide some key new information on seasonal presence of many whale species, as well as helping clarify how far offshore they tend to be during migration (again, especially crucial information for the right whales).

Scientists object to new Atlantic oil/gas exploration plans

Bioacoustics, Ocean energy, Seismic Surveys No Comments »

A letter from 75 leading bio-acoustics researchers urges President Obama to derail current plans to open much of the US eastern seaboard to oil and gas exploration and development.  Last year, the Department of Interior opened the door to new seismic surveys from Delaware to Georgia, which will clarify which areas of the continental shelf are most promising as drilling sites; these could begin as soon as this year or next.  So far, nine applications have been filed for surveys, all 50 miles or more offshore.  In January of this year, Interior announced plans to issue drilling leases beginning in 2017, with the initial five-year leasing period targeting roughly the same region (UPDATE, 3/15/16: Interior cancels lease planning); in conjunction with opening this area, development was banned in some Alaskan waters (small areas off the north slope and a larger area in SW Alaska).

map All this has spurred much public outcry, and in March an impressive array of ocean scientists from dozens of universities and research organizations around the world took the unprecedented step of sending a letter to President Obama expressing deep concern about the acoustic impacts of these plans. “The magnitude of the proposed seismic activity is likely to have significant, long-lasting and widespread impacts on the reproduction and survival of fish and marine mammal populations in the region, including the critically endangered North Atlantic right whale, of which only 500 remain,” say these researchers (see the full letter).

New dynamic maps from NOAA’s new Cetacean & Sound Mapping project indicate that these right whales use the southeast coast intensively in January and February, and are present along much of the coast in March and April moving north, and November and December heading south.  Only during the months of June-October are these whales mostly in northern waters away from the region currently being targeted.  Of course, other marine species are present year-round.

The Department of Interior suggests that since all activity will be more than 50 miles offshore, it should not interfere with commercial or recreational fishing, or near-shore areas of critical habitat; however, airgun sounds are often audible at much greater distances than that.  Energy companies also stress that heavy seismic survey activity in the Gulf of Mexico has co-existed for decades with both commercial and recreational fishing activity.

While initial push-back has largely been focused on the seismic surveys, which use pulses of loud sound to image deep below the seafloor (here’s a good explainer), the longer-term acoustic footprint of oil development is likely to also be significant. Ocean Conservation Research has been focusing on this for several years, tracking the new generation of seafloor processing facilities that are making deep-water development possible:

Much of the technology that makes deepwater drilling possible hinges on creating pre-refineries on the sea floor. These include seafloor separators, reinjection pumps, multi-phase pumps and other equipment all operating under extreme pressures and often very high (and noisy) differential pressures. Additionally these deepwater operations are typically performed from dynamically stabilized drill ships and “semi-submersible” platforms that are always churning away.

Listening array documenting rare natural quiet on BC coast, in face of development proposals

Bioacoustics, News, Ocean, shipping No Comments »

PacificWild, a British Columbian environmental organization, has deployed a network of 6 hydrophones in waters along the northern coast of that province.  This region of offshore islands and dramatic forested fjords is relatively wild, and quiet, especially as compared to the shipping-intensive region in southern BC around Vancouver Island and nearby Puget Sound in Washington State. But development proposals (including tar sands and other oil and gas ports) may mean up to 3000 supertankers per year will pass through these northern waters, bringing an expansion of the acoustic smog that already blankets most of the world’s oceans.

farshot      closeshot

Ian McAllister of Pacific Wild stresses that “Most of the species that are acoustically sensitive rely on a quiet ocean in order to communicate, in order to forage, in order to survive here,” and notes that the hydrophone array will gather crucial baseline acoustic data that can help inform management decisions to be made in the next few years.

Live streams of the hydrophones are available, though at most times, there’s not all that much going on; a collection of highlights, as well as streams, is available on this page. To learn more about the project, see PacificWild’s website, or take a look at this brief video (see it here if it doesn’t load for you).

Navy, NMFS slammed by judge over training permits

News, Ocean, Science, Sonar No Comments »

The Navy and NMFS suffered a stunning legal defeat over the latest 5-year EIS and permits governing training exercises in Hawaii, California, and waters in between.  In marked contrast to other recent court rulings, which found fault with some procedural issues but largely backed the Navy and NMFS’s collaborative planning results (see detailed AEI summaries of 2014 rulings on the Pacific Northwest training range and global low-frequency sonar permits), US District Court Judge Susan Moki Olway vehemently rejected several key aspects of the permitting for the Hawaii-Southern California Training and Testing (“HSTT”) Study Area. (Note: while sonar has been the focus of most public concern, these trainings also involve live ammunition, explosions, etc., that are responsible for most of the anticipated behavioral disruptions and nearly all the injuries and deaths.)

120511bighsttregionWEB

The primary target of the legal challenges was the National Marine Fisheries Service (NMFS), which issues the permits (Letters of Authorization) and the Biological Opinion that underly the permit conditions and take numbers. The Navy’s Environmental Impact Statement (EIS) was not directly challenged (a Supreme Court ruling has left the Navy with broad discretion and little room for legal challenges), but the EIS is accepted as sufficient by NMFS, and Judge Olway made a point of chastising NMFS for being too quick to simply adopt much of the Navy’s reasoning about both the impact on animal populations and the practicality (or lack thereof) of keeping training activities out of some areas.

The ruling seems to call for a fairly substantial revision of the EIS, the Biological Opinion, and the take numbers authorized by the permits; still, it may be likely that these documents can indeed be revised to fix the shortcomings identified by the Court, without substantially reducing the training activities being planned.  Also, an appeal to a higher court is possible, or likely, given the broad implications of the ruling.

UPDATE, September 2015: As it turned out, the Navy and NRDC negotiated a settlement, adding a few exclusion zones for the duration of the current five-year authorization. It remains to be seen how the larger issues raised by the ruling may affect the next round of Navy EIS and NMFS authorizations.

Nonetheless, this ruling is the most fundamental challenge to the current Navy and NMFS planning process since the original lawsuits that helped trigger the Navy to begin producing EISs and NMFS to issue permits.  Among the key issues that were successfully challenged:

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No-go zone proposal splits orca advocates

News, Ocean, shipping No Comments »

A proposal to exclude whale-watching boats from nearshore waters off San Juan Island in Puget Sound has been revived by a local orca protection group, Orca Relief Citizens Alliance.  A similar plan was proposed by NOAA in 2009-11,  but was abandoned after push-back from whale-watching groups, with a speed limit introduced instead.  In recent years, the population of resident orcas has fallen to a 30-year low, and is down to 77 after 4 deaths during 2014, including the first new calf to be born in two years.

“This is only an immediate solution to a dire situation,” said Orca Relief Executive Director Bruce Stedman. “When salmon levels are so low, the whales are very stressed when searching for food. Pursuit from whale watching boats causes more stress.”

However, the proposed “no-go” zone contains just 0.5% of the resident orcas’ federally designated critical habitat and is heavily used by orcas for just a few weeks a year,  so the idea been criticized by both whale watching groups and some orca advocates, including Ken Balcomb of the Center for Whale Research. “The no-go zone is an absurd waste of concern and a futile effort legally,” Balcomb said. “The whales will go where the chinook salmon are in abundance, and it is these fish that should receive our concern.”

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

Bioacoustics, News, Ocean, Science, shipping, Sonar No Comments »

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:

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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.

NJ sues Feds over academic seismic survey planned for July

Effects of Noise on Wildlife, Ocean, Seismic Surveys No Comments »

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 No Comments »

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 No Comments »

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.

UPDATE, July 2016: A federal appeals court has overturned much of this ruling, suggesting that the NMFS failed to meet the “least practicable impact” standard by choosing to include only those 22 OBIAs as exclusion zones.  See details here.

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 No Comments »

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 No Comments »

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.

NATO sonar exercises, strandings in Crete

Effects of Noise on Wildlife, Ocean, Sonar No Comments »

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.

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.

Legal challenges mount to new round of Navy training permits

Effects of Noise on Wildlife, Ocean, Sonar No Comments »

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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New research listening in on whales as they hunt

Bioacoustics, Effects of Noise on Wildlife, Human impacts, Ocean, Science, Seismic Surveys, shipping No Comments »

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

Bioacoustics, Effects of Noise on Wildlife, Human impacts, Ocean, shipping No Comments »

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.”

First ruling in new sonar challenges fails to limit huge take numbers

Effects of Noise on Wildlife, News, Sonar No Comments »

The first ruling is in from the latest round of legal challenges to Naval training permits, and it’s a split decision.  You’ll need to click through to read the full post to get all the details, but here’s a preview of the conclusion you’ll find at the end:

It appears that the places that the court found NMFS falling short are in the details of how they prepare and analyze information, while the end results of the Navy activities and NMFS analysis and permits were upheld as valid. The court did not accept the plaintiff’s core concerns about the huge numbers of animals authorized to be affected (as litigated on the questions of protected habitats, mitigation measures, and cumulative impacts), deferring to the NMFS analysis that deemed even these large numbers to be acceptable, largely because most impacts are minor and temporary. The rulings that went against NMFS each appear to require simply more data analysis, which will then be fed into the same decision-making process that has been upheld as valid. 

In 2012, Earthjustice, NRDC, and others challenged both the 2010 Northwest Training Range Complex permits authorizing five years of mid-frequency active sonar and explosions at sea, and permits authorizing global deployment of low-frequency active sonar through August 2017. While earlier challenges targeted the Navy’s environmental analysisor originally, the lack thereof—and ran aground when the Supreme Court ruled the Navy has broad discretion to weigh environmental safety against national security interests, this new round of lawsuits is directed at the National Marine Fisheries Service’s regulations and permits for the activities. 

In both cases, the primary focus of the challenges, at least as described in press releases, was insufficient protection of biologically important areas.  For several years, NRDC and others have stressed that Navy training ranges, which stretch along nearly the entire east and west coasts of the US, contain enough area for diverse training while setting aside some seasonal or year-round exclusion zones where training is avoided due to concentrations of marine animals.  Navy estimates of the numbers of animals likely to hear sonar or explosions, leading to either behavioral changes or injury, are alarmingly high, and the plaintiffs suggest that these numbers could be reduced significantly by setting some areas off limits, at least at key times. Unlike in previous challenges directed at the Navy itself, the plaintiffs did not seek any sort of injunction to halt the training exercises; rather, they asked that the court require the NMFS to revisit and revise their previous rules or authorizations in light of any deficiencies the court determined to be present.

As the NWTRC case moved into the argument phase, several specific challenges to NMFS procedures, analysis, and conclusions were raised and addressed. In a ruling issued by US Magistrate Judge Nandor Vadas in late September, the plaintiffs came away with at least a temporary win on several points, while the NMFS prevailed on several other fronts, including on the fundamental arguments about habitat protection and long-term impacts.  As in previous rounds of this legal battle, it appears that the end result will be Navy training continuing pretty much as it was before any of the legal challenges began—though with detailed analysis of potential impacts continuing to be pushed into new realms by the legal challenges.

The court ruled that the NMFS had improperly failed to include some relevant studies from 2010 and 2011 when issuing a 2012 Letter of Authorization and Incidental Take Statement, two years after the initial Five-Year Regulations were issued, and so did not rely on the “best available evidence” and likely underestimated the number of animals affected by Navy activity in its 2012 permitting documents.  In addition, the court ruled that the NMFS should analyze impacts not just over the five years of each planning cycle, but for a longer (unspecified) time period, because Navy training is considered to be a permanent, long-term activity.  Over the next month, NMFS will file a brief describing what they see as an appropriate scope and duration of any order to change their previous documents, and the plaintiffs will file a reply; presumably, the Court will rule shortly thereafter on specific remedies.

However, the NMFS prevailed on several substantial issues, including the primary one and two important related challenges.  On the central question of setting aside exclusion zones to better protect essential habitats, the court ruled that the NMFS had given such exclusions due consideration, and lawfully concluded that such exclusions would not be likely to reduce take numbers significantly.  Likewise, the court ruled that NMFS determination of no significant impact did not rely on insufficient mitigation measures (primarily visual observers) in making its assessment of likely harm; rather, NMFS determined that even before mitigation measures were implemented, the numbers of animals affected and the degree of impact did not pose long-term risks to local populations.  

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Powerful mapping sonar likely triggered Madagascar mass stranding

Effects of Noise on Wildlife, Ocean, Sonar 1 Comment »

AEI lay summary of:
Southall, B.L., Rowles, T., Gulland, F., Baird, R. W., and Jepson, P.D. 2013. Final report of the Independent Scientific Review Panel investigating potential contributing factors to a 2008 mass stranding of melon-headed whales (Peponocephala electra) in Antsohihy, Madagascar.
Download full report or executive summary.
See IWC website for report and all supporting materials 

Madagascar whalesWEBFor the first time, a mass stranding appears to have been triggered by a relatively high-frequency mapping sonar; most previous strandings (though rare) have been associated with mid-frequency military sonars.  An international, independent scientific review panel (ISRP) of five well-known marine mammal researchers has concluded that a 2008 stranding event on the northwest coast of Madagascar was likely precipitated by an avoidance response to a multi-beam echo-sounder system (MBES) being used to map the seafloor.

Over a hundred melon-headed whales, deep-water foragers who normally live far offshore, became trapped in a shallow estuary one day after the MBES was active 65km off the coast; locals and international marine conservation organizations collaborated for three weeks to save floundering whales, with at least 75 confirmed dead.  The ISRP investigated all known possible causes for such events, and concluded that the most likely trigger was that the whales were moving away from the sonar, and became trapped in the unfamiliar surroundings of the narrow La Loza Bay estuary.  There, they found it hard to orient and navigate in the shallow, murky water; lack of food sources, stress/fatigue, and an accumulation of small injuries led to eventual death for most.

Madagascar mapWEBAcoustic modeling suggests that the whales would have been able to hear the MBES signals for at least 30km from the survey vessel, to near the island seen on the map to the right, 25km offshore, at which point they apparently continued moving toward shore until straying into the stranding zone.  Why the animals continued moving inshore after the sonar was no longer audible is unclear.  This is a species that normally lives only in deep waters; once the whales moved past the cliff near the survey area and into shallow shelf waters, they may have been quite confused, and further behavioral anomalies (including ending up in the estuary) may be unrelated to the survey sounds.

UPDATE, 10/10/13: This WaPo article includes some skeptical responses, centering on the uncertainties about other factors (before and/or after the MBES sound exposure) that may have contributed to the stranding, and concerns that the strong language of this report could lead to an over-reaction among regulators.  A spokesman for Exxon-Mobil, which helped fund the study and the initial stranding responses, said, “our contract vessel happened to be there in that time frame, but there are so many uncertainties in the area that we’re not sure it’s us.” Still, the company has changed its practices to avoid use of MBES near sharp cliff faces, since the panel speculated that echoes off the cliff may have confused the whales, sending them further inshore.

The ISRP report concludes that “this clearly appears to be an atypical event,” yet also stresses that the MBES system may pose previously unrecognized risks:

It is important to note that these systems, while regularly used throughout the world in hydrographic surveys, are fundamentally different than most other high-frequency mapping or navigational systems (ed. note: or fish-finding sonars). They have relatively lower source frequencies (12 kHz is within the range of likely best hearing sensitivity for all marine mammals), very high output power, and complex configuration of many overlapping beams comprising a wide swath. Intermittent, repeated sounds of this nature could present a salient and potential aversive stimulus.

Click on through for more details on the stranding, the ISRP report, and maps.

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IMO shipping noise guidelines complete, awaiting approval

Ocean, shipping No Comments »

After a couple of years with no progress to report, the International Maritime Organization (IMO) appears to be nearing completion of “Voluntary Guidelines for the Reduction of Underwater Noise from Commercial Shipping.”  This process began in 2008 with a burst of activity and focus from the US and European IMO representatives, but appeared to languish in recent years (see this earlier AEInews report, with links to key documents).

Ship and Barge2

The effort falls under the purview of the IMO’s Marine Environmental Protection Committee (MEPC), which assigned development of the standards to its sub-committee on Ship Design and Environment (DE).  The DE formed a “drafting group” led by the US, and this group has nearly completed its work, with just one paragraph in the preamble still to be solidified.  At its March 2013 meeting, the DE subcommittee approved the draft guidelines; their next step along the long and winding bureaucratic road will be their submission to the full MEPC at its next meeting, in April 2014.

The draft guidelines are currently not publicly available, but the DE meeting summary notes:

The non-mandatory Guidelines are intended to provide general advice about reduction of underwater noise to designers, shipbuilders and ship operators and consider common technologies and measures that may be relevant for most sectors of the commercial shipping industry. Designers, shipbuilders, and ship operators are encouraged to also consider technologies and operational measures not included in these Guidelines, which may be more appropriate for specific applications.

The guidelines give recommendations on predicting underwater noise levels, such as using underwater noise computational models; standards and references that may be used, including ISO/PAS 17208-1 “Acoustics – Quantities and procedures for description and measurement of underwater sound from ships – Part 1: General requirements for measurements in deep water” (see this ISO press release on these new standards); design considerations; onboard machinery selection and location; additional technologies for existing ships; and operational and maintenance considerations.

Here’s hoping that the MEPC is able to take up the Guidelines at their 2014 meeting as planned, completing this modest first step of encouraging the shipping industry to incorporate noise emissions into the design of new vessels.  The ISO/PAS standards will provide clear guidance for measuring the noise footprint of ships, though the IMO is not ready to suggest or mandate any particular maximum noise levels at this time. See this AEInews post on NOAA’s recent ocean noise mapping project; shipping noise is the predominant human contributor to overall ocean noise levels.

SOCAL begins 2013 behavioral response study

Effects of Noise on Wildlife, Ocean, Science No Comments »

The 2013 field season of the 5-year Southern California Behavioral Response study is underway now.  This research applies suction-cup tags to whales, which track the whales’ movements (dive patterns, speed, direction, etc.) while also recording the sounds the whales are hearing, including sounds of mid-frequency active sonar played underwater by the researchers under carefully controlled conditions.  Earlier years’ results have begun to quantify the level of sound that can spur behavioral reactions in several species of whales, including the beaked whales that have appeared to be more sensitive to sonar sound, resulting in several stranding incidents over the past fifteen years.  Most recently, two new papers reported that both blue whales and Cuvier’s beaked whales seem to avoid sonar sounds, and at times stop feeding, at sound levels below most current regulatory thresholds.

SOCAL researchers will be posting updates from the field here.

Behavioral Response Study – Tagging Beaked Whales from Brandon Southall on Vimeo.

Blue, beaked whales stop foraging when exposed to sonar?

Effects of Noise on Wildlife, Ocean, Science, Sonar No Comments »

AEI lay summary of:
Goldbogen JA, Southall BL, DeRuiter SL, Calambokidis J, Friedlaender AS, Hazen EL, Falcone EA, Schorr GS, Douglas A, Moretti DJ, Kyburg C, McKenna MF, Tyack PL. 2013 Blue whales respond to simulated mid-frequency military sonar. Proc R Soc B 280: 20130657. http://dx.doi.org/10.1098/rspb.2013.0657 (download here)
and
DeRuiter SL, Southall BL, Calambokidis J, Zimmer WMX, Sadykova D, Falcone EA, Friedlaender AS, Joseph JE, Moretti D, Schorr GS, Thomas L, Tyack PL. 2013 First direct measurements of behavioural responses by Cuvier’s beaked whales to mid-frequency active sonar. Biol Lett 9: 20130223. http://dx.doi.org/10.1098/rsbl.2013.0223 (download here

Results from studies off Southern California have quantified for the first time the reactions of Blue whales and Cuvier’s beaked whales to simulations of naval mid-frequency active sonar.  In both cases, scientists found that whales tended to move away from sonar signals, and appeared to suspend feeding activity for an hour or more at times.   

The Cuvier’s beaked whale results marked the first time this species had successfully been monitored during a controlled exposure to sound while wearing a temporary suction-cup “D-TAG” that allows researchers to track animal dive and movement patterns while also recording the sound level of the sonar signal that the animal is hearing. As with similar experiments done on other species of beaked whale, the two whales tagged in this study changed their normal dive patterns, paused or stopped echolocating for food, and waited longer at the surface after the sonar sound ended before they began diving normally again.  The pause in foraging lasted for 6 hours in one whale, and at least 90 minutes for the other.  

The whales’ behavior was changed at sound levels (89-127dB) that are far below the levels typically considered problematic by regulators (typically 160-180dB; though some Navy EIS’s use 120dB for beaked whales, because of their previously observed noise sensitivity).
CORRECTION, 1/31/14: The current round of Navy EISs and NOAA permits consider exposures down to 120dB in their analysis of behavioral “takes” for all species.

Researchers concluded that “The observed responses included vigorous swimming and extended time without echolocation-based foraging, imposing a net energetic cost that (if repeated) could reduce individual fitness.”  While they did not see rapid ascents from dives that would support an early theory that some beaked whales may suffer tissue damage similar to what human divers experience as “the bends,” they suggest that the disruption of normal dive and surface-resting patterns could affect the animals’ dive metabolism in ways we don’t yet understand.  Also of interest in this study was an unexpected period during which a tagged animal was exposed to sound from a distant (over 100km) naval exercise; in that case, the animal showed no response, though received levels were similar (78-106dB); researchers suggest that the animals could tell that these signals were much more distant than the test signals, which were under 10km away.

The Blue whale results were a bit more ambiguous, as there was significant individual variation among the 12 whales that were tagged and exposed to sonar-like sounds. Some whales were foraging at the surface, some were deep-diving feeding, and some were diving but not feeding.  Whales at the surface showed little response, while diving animals reacted more strongly, including some instances of clear avoidance (i.e., swimming away, or “horizontal displacement” in the research parlance).  

While the Blue whale results were not as uniform as the Cuvier’s results, this is the first time that blue whales have been studied to see how they respond to mid-frequency sonar, and the researchers consider even the modest effects to be significant, especially since blue whale populations are not rebounding similarly to other large whales.  As the  researchers conclude: “our results suggest that frequent exposures to mid-frequency anthropogenic sounds may pose significant risks to the recovery rates of endangered blue whale populations, which unlike other baleen whale populations (i.e. humpback, grey and fin whales), have not shown signs of recovery off the western coast of North America in the last 20 years.” 

Using a complex set of measurements of 54 behavioral metrics (including such factors as orientation angle to the sound, change in pitch or angle of descent or ascent, and the number of lunges per dive), and applying a statistical formula that resulted in the average “response” ratings on the left axis of the charts below, researchers found statistically significant changes three key areas.  The chart below shows the clear, yet subtle, changes in dive patterns (a), body orientation (b), and horizontal displacement (c), especially among the deep-feeding animals:

CEE blue whales500

Researchers note that the whale that showed the largest reaction stopped feeding as soon as hearing the sonar signal and swam away from the sound; it did not begin feeding again for an hour, during which time it would have eaten over a ton of krill, which is about the minimum amount a whale needs per day (i.e., it’s a metabolically significant loss).  

The responses noted occurred at average peak received levels of 130-160dB, again, notably lower than most regulatory thresholds for behavioral responses, which range from 160-180dB. CORRECTION, 1/31/14: The current round of Navy EISs and NOAA permits consider exposures down to 120dB in their analysis of behavioral “takes” for all species; in fact, the bulk of behavioral responses for “low frequency cetaceans,” such as blue whales, is expected at exposures similar to those here. There was a large range of response ratings for both dive patterns and body orientation (the chart above shows the average among all individuals); the avoidance responses showed a more modest range of variability, except for the one extreme response noted above.  Overall, the results confirm previously-observed importance of behavioral context: “Since some of the most pronounced responses occurred near the onset of exposure but other, higher level exposures provoked no response, the data suggest that the use of received level alone in predicting responses may be problematic and that a more complex dose – response function that considers behavioural contexts will be more appropriate. Management decisions regarding baleen whales and military sonar should consider the likely contexts of exposure and the foraging ecology of animals in predicting responses and planning operations in order to minimize adverse effects.”