For over a decade, the National Park Service has been on the forefront of public lands agencies in addressing the role of sound and noise on both wildlife and park visitors.  NPS’s Natural Sounds and Night Skies Division has catalyzed baseline acoustic monitoring in seventeen parks, and carried out groundbreaking research on the effects of noise on wildlife.

Now, NPS is planning a national survey on how the quality of park soundscapes affects visitation at national parks, and the economies of gateway communities.  An August 9 Federal Register notice is seeking public comment on the value such a study, with the hope of doing a small-scale pilot survey in 2014, in preparation for the full study in 2015.  The last time NPS sought comments on a similar proposal, they received no public comments and did not proceed.  Now’s the time to chime in, as comments close on September 9.  (Go here, and be sure to note the topics they want input on, and send your comments to both email addresses listed.)

“In addition to parsing out the extent to which visitors value being able to hear the sounds of nature, the study will provide other useful information such as how acoustic conditions affect the likelihood of repeat visitation to national parks,” the agency said in a summary of the survey.  

At a daylong public outreach workshop on Noise in Communities and Natural Areas earlier this month (which I was fortunate to attend), Kurt Fristrup and Frank Turina outlined some of the ongoing soundscape work in parks. Turina described a pilot project at Rocky Mountain National park that uses flashing signs to notify motorcyclists of the noise levels of their bikes (much like instantaneous speed-tracking signs), with the goal of encouraging riders to moderate their noise while enjoying park roads.  Fristrup shared some fascinating research revealing that hikers on the Hermit Trail at the Grand Canyon nearly universally reported lower levels of overall satisfaction with their visitor experience after overflight helicopters start flying each morning. Hikers were asked to rate their experience on a 7-point scale, from Very Pleasant to Very Unpleasant.  Prior to the start of flights, Very Pleasant (7) received was the most chosen rating, with no one choosing the lower Unpleasant to Very Unpleasant ratings of 3, 2, or 1.  After flights began, the graph of responses shifted distinctly toward the less pleasant ratings: the number of people rating their experience at 7 dropped dramatically and the lower ratings, all the way down to 1, joined the mix.

Add crabs, and perhaps by extension other crustaceans, to the list of animals negatively affected by shipping noise in the world’s oceans.  

A new study has found that ship noise markedly changes some important crab behaviors:

Working with the same common shore crabs that children delight in catching on crablines in UK harbours, the team found ecologically-critical effects of ship noise-playback on behaviour.

Matt Wale from the University of Bristol said: “Crabs feeding on mussels were often distracted when ship noise was playing compared to quiet harbour recordings. Furthermore, crabs took longer to retreat to shelter after simulated attacks in noisy treatments, and if turned upside-down they flipped back far quicker in noisy conditions rather than turning slowly to avoid attracting attention of potential predators.”

Dr Steve Simpson from Biosciences at the University of Exeter said: “We have already found that ship noise raises the metabolic rate and energetic needs of crabs. If coupled with reduced foraging and worsened responses to predators, this cocktail of impacts may negatively affect growth, fitness, survival and, ultimately, harvested populations and whole ecosystems.”

Cetaceans (whales and dolphins), fish, and larvae of reef creatures have previously been found to respond to shipping noise in ways that can increase energy expenditures and stress levels; this is the first clear indication that crustaceans are also negatively affected.

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.

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:

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.”

Thirty months after environmental groups sued to force ongoing seismic survey programs in the Gulf of Mexico to be subject to more robust compliance with the Marine Mammal Protection Act and Endangered Species Act, a settlement announced this week requires full EIS’s to be completed within thirty months from now.  In the meantime, surveys will be kept out of three key biologically important areas, as well as from nearshore waters during the spring calving season of bottlenose dolphins.  In addition, the oil and gas industry committed to continue working on alternatives that may affect sea life less widely, particularly vibroseismic techniques that would vibrate the seafloor directly (similar to a technique widely used for onshore oil and gas exploration), rather than via loud explosive sounds from airguns.  

And, the Bureau of Ocean Energy and Management will develop new standards to assure that airgun surveys are not unnecessarily duplicative.  Dozens of surveys take place every year in the Gulf, with repeat surveys sometimes needed to assess reservoir depletion, and as new and improved imaging capabilities are developed; often, survey results are considered proprietary, especially prior to bidding on leases.

3D seismic imagery, above; airguns firing, below.

“Today’s agreement is a landmark for marine mammal protection in the Gulf,” said Michael Jasny, director of NRDC’s Marine Mammal Protection Project. “For years this problem has languished, even as the threat posed by the industry’s widespread, disruptive activity has become clearer and clearer.”

Of particular concern are several populations of whales that are relatively few in number, and thus vulnerable to any disruption—in particular, the Gulf’s small population of sperm whales, whose nursery in Mississippi Canyon was ground zero for the spill. In 2009 an Interior Department study found that Gulf sperm whales subjected to even moderate amounts of airgun noise appeared to lose almost 20 percent of their foraging ability, which may help explain why the population hasn’t recovered from whaling.

International Association of Geophysical Contractors (IAGC) President Chip Gill stated, “Under the settlement agreement, permitting of seismic surveys in the Eastern Gulf of Mexico will continue. (The exclusion zones) are all areas where no lease sales are scheduled and where the prospective areas have recently been surveyed using modern surveying technology. . . . Some of the mitigation measures in the settlement agreement are voluntarily employed by industry around the world. Many of the others have been employed by industry in the GOM for the last several years.”

One of the new requirements that may not have been widely used in the Gulf is the employment of listening devices to help identify whales that may be nearby but unseen by observers scanning for surfacing whales.  As with the controversy over Navy noise-making, much of the nitty gritty of the new EIS process will focus on subtle behavioral impacts, and the difficult question of how much such disruption is tolerable while maintaining the health of animal populations.  A recent scoping hearing in Florida, marking the beginning of the long EIS development process in one zone of the Gulf, included some back and forth on this question.

For a full list of the settlement requirements, see this CBD press release.
Previous AEI coverage here and here.

RELATED: Australian environmentalists are upset about seismic surveys OK’d in an area important to blue whales.  According to an article in The Standard, “Government guidelines are clear that seismic surveys should avoid places and time of year when whales are highly likely to be present,” said Michael Collis of the International Fund for Animal Welfare. “We can’t think of a clearer example of this than Australia’s largest ever sighting of blue whales. People should view noise pollution the same way they view chemical pollution. The scientific community is slowly waking up to what a problem this is.” Collis said the fear was the giant mammals could be displaced from their feeding grounds, causing unknown repercussions, and knocked back suggestions that environmentalists opposed all off-shore gas mining exploration. “In Australia there are over 300 oil and gas reserves. We are talking about five areas that are special to whales,” Mr Collis said.

On June 9, 2008, 26 common dolphins, 21 of them infants, stranded and died in river estuaries around Falmouth Bay, as several days of Naval exercises involving over 30 ships wound down (see AIEnews coverage at the time).  A four-year study (read it online) has  concluded that unspecified Naval activities are “the most probable (but not definitive) cause” of the strandings, which involved at least 60 animals in all, with most of the adults re-floated and guided back to sea.  

The study ruled out other common causes of cetacean strandings, including foraging for fish in shallows, attack by orcas, illness, algal toxins, recreational boats, and earthquakes.  However, the researchers also could not identify a likely trigger among the Naval activities taking place on the morning of the strandings or the day preceding the discovery of the struggling animals.  Press reports at the time suggested that locals heard some large explosions on the day before and day of the strandings, though the researchers did not find records to indicate such activity. Mid-frequency sonar transmissions ended four days earlier; that or other ongoing activity is thought to have driven the dolphins into the bay, with unknown further disruptions triggering the fatal strandings early on the 9th.  According to lead author Paul Jepson, “Eyewitnesses described their behaviour as swimming continuously in tight circles, being vocal, fluke-slapping, leaning sideways, and often with one or more individuals attempting to strand.” 

The lack of a clear cause for the final stranding event during a relative pause in Naval activity on the day before the early-morning discovery of the floundering dolphins adds a familiar ambiguity to the situation.  A Naval spokesman noted that they disagreed with the report’s conclusion and stressed their decades of similar exercises in the area without mass strandings, while conservation groups including the NRDC and the UK-based Whale and Dolphin Conservation called for exercises to be redesigned. While cetaceans can often move away from unwanted noise, it’s long been known that strandings can occur when animals become trapped in areas with no escape route, such as apparently happened here.

Despite Naval denials of responsibility, this event did spur some changes that have led to later exercises being temporarily suspended when dolphins appeared on the verge of being trapped in a similar situation.  As detailed in the new study:

Following this MSE (Mass Stranding Event) and recommendations from the organisations involved in the rescue of dolphins in the MSE, the UK Ministry of Defence initiated the Marine Underwater Sound Stakeholders Forum in the UK to regularly meet with all interested stakeholders (scientists, other Government Departments like Defra and a range of non-Governmental organisations) to discuss these issues in some detail. A direct line of communication was also established after the Falmouth MSE to facilitate rapid exchange of information between cetacean strandings/sightings organisations and Royal Navy Naval Command Headquarters to report groups of pelagic cetaceans seen unusually close to shore and potentially at increased risk of stranding. This was used to report a near-MSE of over 20 common dolphins in the Fal estuary in April 2009 that was seen 15 minutes after RN sonar trials were initiated in the region. The RN immediately modified the naval exercise (including use of active sonars) until the group of dolphins had returned to open sea several hours later. The need to alter training excercises due to the presence of dolphins has not subsequently occurred in this region.

According to the authors, “Such continual improvement of mitigation strategies by the military themselves is probably the best way to limit future environmental impacts of naval activities, including cetacean MSEs.”

When the US Forest Service initiated far-reaching Travel Management planning in 2005, mandating that all National Forests analyze off-road vehicle use on their lands, and specify roads and trails where off-road vehicles would be allowed, wilderness and quiet-use advocates were thrilled.  Before that, many forests allowed free-ranging use of ATVs, dirt bikes, and other vehicles on any trail not specifically designated as off-limits with posted signs.  Thanks to the all-too-common practice of removing such signs, along with the more-than-occasional off-trail use that created “new” trails over time, the new rules, which turned the tables by allowing vehicles only in areas clearly designated for their use was a big step forward.  Those traveling by foot could look forward to having a bit more separation between themselves and lovers of motorized recreation; often, ridgelines separated basins where visitors could expect to find substantial natural quiet.

Except in winter.  The groundbreaking Travel Management Rule specifically exempted snowmobiles from being subject to the limits contained in each forest’s local Travel Management Plan.  The reasoning was that many of the damaging aspects of unfettered ORV use were less relevant in winter; in particular, damage to vegetation and streambeds, and all the related risks of increased erosion.  These impacts are indeed significantly less in winter, though some soil compaction can occur beneath snowmobile trails over meadows.

But one key impact from motorized use can actually be worse in winter: the noise footprint of the vehicles.  Thanks to better sound transmission in cool air and across frozen, leafless landscapes, the sounds of snowmobiles often travel much further than the sounds of ATVs and dirt bikes in summer. This can clearly impact other forms of recreation, as well as disturbing animals who are sensitive to noise intrusions. In Idaho, lovers of “quiet recreation” worked hard to get snowmobiles included in national and regional travel planning, and when they failed, the national Winter Wildlands Alliance took the question to the courts.

This week, a Federal Judge in Boise agreed that the exclusion of snowmobiles from an otherwise comprehensive approach to travel management planning was “arbitrary and capricious” and “contrary to law,” ordering the Forest Service to revise the 2005 Travel Management Rule within 180 days to include snowmobile management.  According to the AP:

Mark Menlove, executive director with the Winter Wildlands Alliance, said the decision was a monumental victory for backcountry skiers and other winter recreationists seeking a peaceful experience in the woods.  The group’s goal is to not shut down snowmobiles in national forests, but force the agency to designate specific boundaries that carve out distinct areas for those who want to explore on powered sleds and those preferring skis, snowshoes and hiking boots.

“Many of our members use snowmobiles more and more to get to certain places, so we’re not in any way asking the forest service to ban them,” Menlove told The Associated Press on Monday. “But we are asking for some balance there, where our constituents can go and find peace and powder snow in the backcountry.”

While this ruling applies only to National Forests in Idaho, it may lead to similar reviews and expansion of travel management planning nationwide.  

Researchers at Woods Hole Oceanographic Institution (WHOI) have completed a proof of concept study that appears to be able to identify individual whale calls in the data collected by seismic surveys.  In the initial data, the researchers were able to cull fin whale calls from the recordings made as airguns blasted their pulses of sound into the ocean floor.  Blue whales are also likely candidates for being heard on the recordings, since their calls also overlap with the frequencies of interest to seismic mapping efforts.

“We have a huge amount of data that can say, ‘Did they change their behavior? Did they stop feeding? Did they stop talking? Did they talk louder?’, and that’s what we want to know,” said WHOI seismologist Dan Lizarralde.

Lizarralde and collaborators are currently seeking funding to develop a computer algorithm that can help with the daunting task of extracting the whale calls from massive amounts of seismic survey data.

For the full story, including spectrograms and comments from other researchers, see this story on LiveScience.com

The California Coastal Commission has rejected the Navy’s 5-year plan for training and testing activities that recently received provisional approvals from the National Marine Fisheries Service.  In a unanimous vote, CCC members said the Navy’s environmental studies failed to back up its claim that impacts on marine life would be negligible during the years 2014-2019.

The Navy’s studies and permit requests suggest that its activities off Southern California could cause 9 million behavioral impacts, 2000 injuries, and up to 130 deaths, though the Navy and NMFS expect impacts to be far lower, and whatever effects do actually occur to have negligible biological impact on populations.  The CCC wants to see more solid science to back up the Navy’s claim that the large numbers will not reflect actual impacts.  Contrary to the Navy’s claim that their projected impact numbers are much higher than what will actually occur, Michael Jasny of the National Resources Defense Council told Commissioners, “We think these are underestimates.”  (See previous AEInews coverage of the Navy and NMFS assessments: New NMFS Navy “take” permits: outrageous or reasonable?)

During the previous 5-year planning round, the CCC took a similar stand, and a Federal Court agreed to some additional precautionary requirements that somewhat limited Navy operations; that ruling led first to a Marine Mammal Protection Act exemption issued by President Bush, and finally to a Supreme Court ruling granting the Navy broad discretion to make operational decisions, and limiting court oversight.

Mark Delaplaine, a coastal manager for the CCC, noted the difficulty of assessing actual impacts: “I’m just torn between the fact that we haven’t seen strandings in this area, and these very large numbers (in Navy estimates) that are really a cause for alarm,” he said.  Still, he stressed that “you have to have additional precautions….It doesn’t make sense to train where there are large amounts of sea mammals.”

The CCC asked the Navy to voluntarily adopt a set of additional precautions in California waters, including larger safety zones in which they would shut down sonar and explosive operations when animals are nearby, avoiding several designated marine sanctuaries and areas known to host seasonal concentrations of blue, fin, and gray whales, and remaining at least 1km (a bit over a half mile) offshore.  The NRDC concurs with these requirements, and encourages a couple more, including avoiding sonar and explosive activity at night, when nearby animals are much harder to detect, and using the Navy’s instrumented ranges to help detect animals.

The Navy declined these requests. “We understand that the Navy is obligated to be consistent with the state’s coastal zone requirements, to the maximum extent practicable,” said Navy spokesman Mark Matsunaga. “And we believe we are.”

For more details on the hearing, see these articles from the Orange County Register and AP.  For a deeper look at the Navy and NMFS studies, see the AEInews lay summary of the Atlantic and Pacific 5-year plans.

It’s been a couple of years since we’ve checked in on the eternal Snowmobiles in Yellowstone debate, and in what’s sure to be a shock for those who’ve been following the issue since the Clinton administration, not much has changed!  During Team Obama’s first summer, Ken Salazar announced that the ongoing string of temporary winter use plans would be extended for a couple of years while the NPS accepted comments on yet another round of EIS preparation.  The Clinton adminstration completed an full EIS process, and announced its final ruling (which banned snowmobiles) just in time for the winter during which W was sworn in; the Bush NPS team suspended that plan and launched a brand new round of comments under a new set of temporary rules.  While the Bush plan didn’t ban snowmobiles, it did require, for the first time, that all groups of snowmobilers go with a local professional guide.  This requirement led to a dramatic decrease in snowmobiles entering Yellowstone; most snowmobilers prefer being able to be footloose, and the huge expanses of National Forest land in the region became their preferred playground.  Complicating implementation of that plan, however, were dueling Federal court rulings that appeared to contradict each other; some of these uncertainties lingered on into 2009, as the Obama administration began overseeing the process.

In the years since, the two-year extension of the Bush-era temporary plan stretched to four, and finally the new proposed plan has been released.  In truth, it isn’t all that different than the Bush plan in terms of total numbers of snowmobiles and snowcoaches, though it tweaks a few elements in ways that may reduce some impacts, especially air quality, over time.   It seems likely that the noise impacts will be roughly similar to those documented in a series of studies we covered here in 2009, in which NPS researchers found that snowmobiles or snowcoaches were audible over half the day in many popular areas, including at Old Faithful 68% of the time, and 59% of the time at Madison Junction.  Still, the new plan does include some absolute dB limits for snowmobiles (67dB) and snowcoaches (75dB), and requires best-available technology on all vehicles by five years from now. The plan opens the door a crack to unguided groups (allowing one per day from each Park entrance), and continues the expensive practice of using explosives to keep a rarely-used pass open to snowmobiles (at the behest of the businesses in nearby Cody, Wyoming).  While the plan slightly increases the average number of snowmobiles to be allowed (from 318 to 342), the actual daily average over the past several winters has been under 200 per day.

Given that previous plans have triggered lawsuits from both environmental groups seeking stricter rules and local business interests wanting fewer restrictions, it’s probably a good sign that both the Greater Yellowstone Coalition and the snowmobile group Blue Ribbon Coalition responded with generally positive comments, while unlike 2009, no instant legal challenge came from the State of Wyoming, either. Fatigue has finally settled in, it appears, as the BRC’s spokesman suggested: “I think for my organization it would be important to resolve this and come up with a long-range plan that doesn’t get challenged in the courts.”

For detailed coverage of the new plan, see this article from National Parks Traveller.  The local Billings Gazette is always a good source for those wanting to track how this all unfolds.

The release of Proposed Rules to govern US Navy training and testing operations in the waters of the Atlantic, Gulf of Mexico, Southern California, and Hawaii from 2014-2019 has put the National Marine Fisheries Service (NMFS) in the crosshairs of an outraged response from environmental groups.  NRDC, the Center for Biological Diversity, and others point to the staggering numbers of “Level B” harassment that will be allowed: over 31 million incidents, along with “Level A” injury predictions including permanent hearing loss numbering in the thousands, capped by several hundred deaths.  These numbers reflect far more than sonar training; also included in these permits are impacts from ongoing training and testing of systems used in live gunnery and torpedo exercises, explosive mine-neutralization, air, surface, and submarine battle exercises, and ship-shock trials (in which large explosives are set off near ships to test their resilience).

“We’re talking about a staggering and unprecedented amount of harm to more than 40 species of marine mammals that should give any federal agency involved, be it the Navy or the National Marine Fisheries Service, pause,” NRDC attorney Zak Smith said in a statement.  The take numbers are generally about twice as high as those in the last round of permitting, which covered a five year period from 2009-2013.

“We absolutely share the concern about protecting marine mammals,” said Alex Stone, an environmental program manager with the Navy’s Pacific Fleet. “We think that the mitigation measures are effective, but it’s true, you’re never going to see every marine mammal that’s there. But in terms of impacts on species, we really haven’t seen any of those after years and years of doing these same types of training and testing activities in these same areas.”

“That’s always been a dubious argument but in light of new information it’s wearing especially thin,” said Michael Jasny of the Natural Resources Defense Council, in a KQED segment. “We now know that beaked whales off California are declining precipitously. We know that blue whales aren’t recovering.” Jasny says the Navy should avoid key areas, like gray whale migration routes and the summer feeding grounds of endangered blue and fin whales. “Southern California is a globally important feeding habitat for them,” said Jasny. “It should be elementary common sense to avoid the core feeding habitat of blue whales. “

How could NMFS sign off on such a seemingly devastating number of permitting takes?  Well, as is often the case, the picture isn’t quite as clear as the headlines may make it seem.  Indeed, we are once again thrust into a funhouse-mirror world of wildly divergent ways of framing the proposed plans.  Press releases and resultant popular press headlines trumpet the NMFS rule as “allowing the Navy to harm whales, dolphins more than 31 million times,” with the permitted incidental takes being described as including “a wide range of harms, including destruction of habitat, physical injury and death.”  The Navy’s statement offers a much more sanguine perspective on the tens of millions of behavioral takes, describing these effects as “e.g., turning head, changing swim direction.”  Huh? What to make of all this?

I dug into the Draft EISs and Letter of Authorization requests developed by the Navy, and the two Proposed Rules announced in January, in order to try to understand how Navy and NMFS biologists could have approved the scary numbers.  I came away far less freaked out, though still disappointed that the Navy and NMFS don’t appear ready or willing to keep noisy Navy activities out of some biologically rich areas.  This has been one of the central points of contention pushed by environmental groups for the past few years, and it remains valid to ask why this practical protective step has not been taken, at least regarding explosive activities with a higher risk of injury. (The vast distances over which some of these sounds travel likely means that exclusion zones to avoid behavioral “takes” may need to extend up to 50-100 miles from the regions of concern in order to provide full protection from noise disruptions; the practicality of such large exclusion zones may be harder to establish, though worthy of discussion.)

After a few hours of reading and digesting several hundred pages of environmental analysis and permitting documents, I was able to distill a few of the key take-aways that may help readers to understand NMFS’s reasoning, as well as the shortcomings of the plans.  Click through for my ten-minute version of what’s in these permits.

Read the rest of this entry »

Deepwater Wind, developers of a proposed 5-turbine wind farm off Block Island, Rhode Island, has agreed to refrain from pile driving for one month a year in order to minimize impacts on critically endangered North Atlantic right whales.  Pile driving, a key part of building the foundations for shallow-water offshore wind turbines, is the loudest aspect of offshore wind construction and operation.  Deepwater Wind, in consultation with the Conservation Law Foundation (which is deeply involved in right whale protection), agreed to suspend pile driving in April, the time of year when right whales are most commonly present in nearby waters.

In the wake of NOAA’s large-scale ocean noise mapping project, two much more detailed studies from the Pacific Northwest have highlighted the likelihood that current shipping noise is already pushing the limits of what biologists think many ocean creatures can cope with.

The first study recorded the sound from several types of boats and ships traversing Admiralty Inlet, between Whidbey Island and Port Townsend, WA, and used these recordings, correlated with ship traffic records, to model sound levels throughout the area.  The Seattle Times summarizes this work, which found that at least one large vessel (container ship, ferry, or large tug) was in the area at least 90% of the time, and that the average noise level was about 120 decibels, which is the threshold above which federal agencies begin being concerned about behavioral impacts on some ocean species.  

“Continuous noise at that level is considered harassment of marine mammals,” said University of Washington’s Christopher Bassett, one of the authors of the paper. “About 50 percent of the time, we even exceed that threshold.”

“It is concerning that the noise levels are so high,” said Marla Holt, a research biologist at Seattle’s Northwest Fisheries Science Center. “When you see how often this happens and how chronic the noise exposure is, that’s when you start to say, ‘Wow.'”

Interlude: Brief OrcaLab recording of threatened Northern Resident killer whales in Caamano Sound, BC, chatting with each other and then being drowned out by a cruise ship:
 

To the north, another study mapped shipping noise in the Salish Sea (south and east of Vancouver Island), and on up the British Columbia coast to the port of Prince Rupert.  This work, funded by World Wildlife Fund-Canada, introduces a comprehensive approach to modeling sound transmission from ships, incorporating differences between vessel types, transmission loss in a variety of bathymetric and seabed conditions, and temperature-driven variations in sound speed during different seasons. (Download a PDF presentation summarizing the full WWF-Canada report here; a shorter version appeared in JASA in November). Here, too, large areas are subject to excessive shipping noise; the maps below show total sound levels, and the areas where the annual average of two specific low frequencies are above the 100dB threshold that the European Union considers the target for biologically sensitive areas:

But now, check out that lighter colored patch about halfway between BC’s two big offshore islands.  

That’s an inland waterway that heads up to Kitimat, the proposed site of a major new port, the Northern Gateway, which would serve as the primary port for shipping tar sands oil to Asia.  An annual total 220 super-tankers would head though that currently mostly-yellow zone, all the way up that long, narrow channel that points to the upper right hand corner of this close-up (and leave again—so more than one passage a day on average).  As you might imagine, there is widespread concern about the risks of accidents and spills in these often treacherous passages, but the increase in shipping noise is also being raised as a question.

A second study by the same research team, led by Christine Erbe, took a close look at current and likely increases in shipping noise, should Northern Gateway go forward, and what they found is not reassuring.  Noise levels will increase by up to 6dB in the approach lanes in Caamano Sound, and by 10-12dB in the narrow fjord into Kitimat (see map on right).  In the western channel (the wider approach), where sound would likely increase 3-6dB (representing a doubling to quadrupling of sound energy), Humpbacks would hear tankers and their accompanying two tugboats for 43% of daylight hours, and orcas (due to thier higher-frequency hearing, less intruded upon by low-frequency ship noise) would hear the tankers 25% of the time.  Fewer whales venture all the way up the fjords, but some would likely be present in the bend in the route, where noise levels would increase by 10dB, representing a 10-fold increase in sound energy.

“There is a worry they will go away and not come back to these fiords,” says Erbe. “This is critical habitat, important to them. Are they going to be able to feed elsewhere? We can only answer that with long-term monitoring.”

These studies, one of which utilized four seasons of recordings, and the other presenting a comprehensive and verifiable sound modeling approach, both offer exciting steps forward in the study of coastal and oceanic acoustic habitats.  Let’s hope that coming years produce many more studies from other regions around the world that continue to develop these innovative techniques.

Detailed Northern Gateway study: Erbe, C., Duncan, A., and Koessler, M. 2012. Modelling noise exposure statistics from current and projected shipping activity in northern British Columbia. Report submitted to WWF Canada by Curtin University, Australia.

BC sound modeling study: Erbe, C., MacGillivray, A., and Williams, R. 2012. Mapping Ocean Noise: Modelling Cumulative Acoustic Energy from Shipping in British Columbia to Inform Marine Spatial Planning. Report submitted to WWF Canada by Curtin University, Australia.
Shorter version:   Erbe, C., MacGillivray, A., and Williams, R. 2012. Mapping cumulative noise from shipping to inform marine spatial planning.  J. Acoust. Soc. Am. 132 (5), November 2012. 423-428.

Puget Sound study: Bassett, C., Polagye, B., Holt, M., Thomson, J. 2012. A vessel noise budget for Admiralty Inlet, Puget Sound, Washington (USA). J.Acoust.Soc.Am. 132(6), December 2012

Related:
Kathy Heise and Hussein Alidina.  Ocean Noise in Canada’s Pacific Workshop, January 31-February 1, 2012.  Summary Report.  WWF-Canada.  54pp.  Read or download PDF

WWF-Canada Submission to Enbridge Northern Gateway Joint Review Panel, 9/19/12. (mostly terrestrial impacts; some ocean noise sections) Read or download PDF

Boston’s WBUR recently interviewed Jesse Ausubel, of Rockefeller University and Woods Hole Oceanographic Institution, about an ambitious project dubbed the Quiet Ocean Experiment.  The idea is to dedicate a year to making detailed observations of wildlife responses to temporary reductions in normally noisy ocean activities, and ideally, to spur a period of several hours to a day during which nearly all human activity in the oceans might cease, in order to see what effect that may have.  Rather than studying the impacts of new noise sources, Ausubel and his colleagues hope to see what removing sound might do.

Here’s a link to a transcript of the five-minute interview.  Or listen below:

As the US Federal government takes up a petition calling for the removal of Puget Sound’s resident orcas from the Endangered Species list, a lack of funding at NOAA continues to hamper efforts to enforce regulations meant to protect them from harassment by whale watching boats.  Seattle’s Q13 TV news team tells the sorry tale here, in both a text and 7-minute video version. Meanwhile, the area’s shipping din may increase yet again, as an EIS Scoping Period has begun as the Army Corps of Engineers begins planning for what could be the nation’s largest export facility, the Gateway Terminal, proposed for shipping coal to Asia. 

NOAA Fisheries announced on Monday that it would review the status of the southern resident population of killer whales, in response to a delisting petition from California farmers.  In addition to  boat noise, a decrease in salmon runs is a key driver of reduced orca populations, and protection plans for the orcas include protections for salmon, including maintaining river flows.  The farmers claim this is denying them the water they need.  The heart of the petition is a challenge to NOAA’s determination that this local population is genetically distinct and deserving protection, although the species as a whole is not threatened.

The Seattle Times has a good detailed article on the challenge, including this reaction from Fred Fellerman, who has championed the ESA listing from the beginning:

“Oh great, here is a chance to biopsy them and tag them and chase them all over town until we don’t have to worry about them any more,” Felleman saidTo hi.  m, the distinct behavior of the southern residents sets them clearly apart from other orcas. They eat only fish, while other orcas eat seals and other mammals. They have distinct family groups, dialects, greeting ceremonies and migratory patterns.

“If there was ever a poster child for this type of subspecies, it’s the killer whales,” he said. “It’s not just their genetics, it’s culture. These clearly are the tribes of the sea, and if you extirpate that population not only do you lose the genetic code, you lose a unique brain trust.”

The question of whether the southern resident killer whales are a genetically distinct population ran through the early years of the listing question, with NOAA initially determining they were not, a court ruling that the question should be studied more thoroughly, and a science task force finding they are distinct enough to warrant protection.  One of two populations in the area (the other ranges over a wider area, and passes through seasonally), the southern resident population is under a hundred individuals.

An article in The Province, a BC newspaper, fleshes out the controversy a bit more:

“Don’t forget that the whale’s listing is based on the government’s seat-of-the-pants determination in 2005 that there suddenly existed an unnamed and theretofore unknown subspecies of killer whale in the North Pacific,” says the Pacific Legal Foundation’s Liberty Blog. “Our delisting petition is not anti-whale, but it certainly is pro-farmer and pro-freedom.”

“The petition presents new information from scientific journal articles about killer whale genetics, addressing issues such as how closely related this small population is to other populations, and meets the agency’s standard for accepting a petition to review,” says a NOAA release.

The petition exasperates Howard Garrett of Orca Network, a Washington state-based non-profit advocacy group for Pacific Northwest whales, but he believes the National Oceanic and Atmospheric Administration is simply doing due diligence.

“I think NOAA is duty-bound to review it, but I don’t think they are going to do anything about it,” he said. “[The Pacific Legal Foundation] is dressing it up as science … but it’s way out of the consensus of geneticists.”

Researchers from Woods Hole Oceanographic Institute have begun a 2-3 year project that will monitor the soundscape at the Cape Wind site before, during, and after construction of the planned 130 wind turbines.  This is the first time such a long-term acoustic monitoring study has taken place at an offshore wind site.  

“We want to evaluate the importance of this kind of research for future offshore wind farm development, which is a rapidly growing field of interest in the U.S.,” Aran Mooney said. He and his colleagues are outlining a methodology for how acoustic monitoring may occur in other wind farm construction. Mooney said, “That will be valuable for industry, policymakers, and the public.”

Two kinds of acoustic recorders are being used: one records the full range of frequencies continuously for a week at a time; the other samples one minute of sound every ten minutes for 2-3 months, at frequencies up to 40kHz (thus missing echolocation clicks but capturing most other vocalizations of interest). “So we’re making the best of both worlds, putting one device out to get a really in-depth look for one week, and then we continue with the other device to get a sampling period of several months, then we replace both,” Mooney said.

During wind farm construction, pile driving will add significantly to existing human noise in the area; at European wind farm sites, some species tend to move  as far as 20km away during construction.  During operation of the wind farm, noise is not expected to be audible at distances more than a few tens or hundreds of yards, but this study will help to quantify exactly what frequencies are propagating into the waters.

Mooney would like to see the project also contribute to a growing research focus on using sounds to monitor overall environmental health of various habitats.  “Animals make sounds when they attract mates or reproduce, and you can track those activities just by listening,” Mooney said. “What I’d love to do with this project is to look at biological diversity. In a nice healthy habitat, you have a spectrum of sounds: low-frequency sounds of fish, then invertebrates a little bit higher, and then the seals and the dolphins.” The soundscape of an undersea area under an environmental stress would sound different; the impacts could be assessed by listening to what’s missing, for example.

For more on the project, see this page on the WHOI website, which also includes recordings of more than a dozen species of ocean creatures.

At long last, I’ve completed this year’s overview of science and policy developments on wind farm noise issues.  It features over 50 pages of new material, along with about the same in Appendices consisting of three research summaries I wrote earlier in the year.  You can download a pdf version of Wind Farm Noise 2012 here. 

AEI’s three Wind Farm Noise annual reports go into depth on different topics, and they complement each other quite well, though each one clearly engages the issues with more detail and reflects a more nuanced appreciation of the topic than the ones that came before. You can access all three, and AEI’s other publications on the issue, on our Wind Farm Noise Resources page.

But today, this is the one you should take a look at! AEI Wind Farm Noise 2012: Science and policy overview

2012 is shaping up as the year when the legal battle over the US Navy’s active sonar systems ramped back up to full-scale confrontation.  A 2009 agreement between NRDC and the Navy put legal challenges on the back burner – actually, entirely off the stovetop – in favor of dialogue.  But recent permits issued by NOAA’s National Marine Fisheries Service (NMFS) are now being attacked for the small sizes of the off-limit areas.  NRDC has continued to call, in pubic and presumably in private, for the Navy to keep their sonar activity out of biologically important areas as they move forward with both low-frequency (LFAS) and mid-frequency (MFAS) active sonar deployments.  This week, a new set of rules to govern LFAS was challenged in federal court on the grounds that the exclusion zones are far too limited.  In January, a similar challenge was filed for existing MFAS permits issued by NMFS; see this earlier AEI coverage for details on the MFAS action.

The new suit, like the January one, differs from the initial round of sonar challenges in that the target is the NMFS permits, rather than the Navy’s operations.  As you may recall, the Supreme Court ultimately ruled that Naval priorities deserved wide latitude in the interpretation and implementation of environmental laws.  By challenging NMFS’s analysis of the risks and the mitigations included to protect marine wildlife, these challenges may well take a different path through the legal maze.

The new LFAS rules allow the Navy, for the first time, to operate the high-power sonars in most of the world’s oceans.  The previous 5-year planning process focused on the western Pacific (in part due to the US stategic focus/concern on China and North Korea, and in part due to legal pressure during that round of planning).  A previous AEI post goes into some detail on the new LFAS “letter of authorization,” which covers the first year of the 5-year period (short version: during the first year, operations will remain predominantly in the western Pacific, with a couple of operations north and south of Hawaii).

In a statement, NRDC says:

Because a single LFA source is capable of flooding thousands of square miles of ocean with intense levels of sound, the Navy and NMFS should have restricted the activity in areas around the globe of biological importance to whales and dolphins.  Instead, they adopted measures that are grossly disproportionate to the scope of the plan – setting aside a mere twenty-two “Offshore Biologically Important Areas” that are literally a drop in the bucket when compared to the more than 98 million square miles of ocean (yes, that’s 50% of the surface of the planet) open to LFA deployment.  The apparent belief that there are fewer than two dozen small areas throughout the world’s oceans that warrant protection from this technology is not based in reality.

NRDC also stresses that the LFAS is loud enough to remain at levels that can cause behavioral disruptions at up to 300 miles away.  The Navy has said that take numbers, especially takes for injuries or death, will be low or zero once mitigation measures are implemented, though the permits allow for some of these “Level A” takes; for the first year, they are authorized to kill or injure up to 31 whales and 25 seals and sea lions.

Oregon Public Broadcasting recently sent reporter Ashley Ahearn out with the researchers that are listening in on orca activity underwater (covered here last month), and her wonderful, detailed report is now online; check it out!  It includes two videos, one showing a tagged orca’s swimming track, along with every boat in its vicinity over the several hour journey, and the other offering a “poles-eye view” of attaching the D-tag to an orca:

Brad Hanson and colleagues at NOAA’s Northwest Fisheries Science Center are currently conducting a second year of exciting new acoustics field research with the Southern Resident killer whales of Puget Sound.  As they did last year, researchers are attaching suction-cup digital acoustic recording tags (DTAGs) to orcas; the tags remain attached for up to four hours, all the while collecting both dive profile data and recording the sound heard (and made) by the animal.  Hanson says that “we’re interested in trying to figure out if the noise levels are interfering with the whale’s ability to communicate effectively during foraging and or actually interferes with their foraging.”

A US District Judge has ruled against NRDC and others who had challenged the Navy’s permit to build an instrumented training range off the coast of Georgia and Florida, claiming that construction should not proceed until the Navy completes the full EIS for the training activities that will take place there.  Construction is slated to begin within a couple of years, with training commencing sometime around 2018; the range would have about 300 sensors installed on the ocean floor over an area of about 500 square miles, and would host training missions involving submarines, surface ships, and airplanes.

The Undersea Warfare Training Range (USWTR) would begin 50 miles offshore, while a key winter birthing and nursing ground for North Atlantic right whales extends out to 20 miles offshore.  Only about 400 North Atlantic right whales remain, with ship strikes being a major concern, along with the effects of any additional stress on mothers or young whales near the Navy’s operations. “We understand that’s the right whale’s critical habitat,” said Jene Nissen, the range’s program director. “We looked at the type of effects that training could have on right whales, and we are confident it will be very minimal.”  Construction will be suspended from November to April, when the whales are migrating and congregating in the birthing grounds, but the Navy has not agreed to suspend training in those months, or to comply with offshore speed limits imposed on private and commercial ships, saying that this would interfere with their ability to carry out realistic and effective training.

The groups that filed the suit in 2010 are considering an appeal; Sharon Young of the Humane Society of the United States stressed that “We certainly would never argue to undermine our national defense, but it’s also reasonable to ask the military not to jeopardize a species that is just barely hanging on.”

See more AEInews coverage of the USWTR here.

In August, the National Marine Fisheries Service issued its Record of Decision that will allow the Navy to operate its Low Frequency Active Sonar systems for the next five years.  NMFS will issue a new Letter of Authorization each year, in order to accommodate new information as needed, but the overall parameters of the permits will remain essentially the same throughout the five years.

While the Final Rule allows the Navy to operate the SURTASS-LFA sonar in most of the world’s oceans (Pacific, Indian, Atlantic Oceans and Mediterranean Sea), the Navy’s operational plans for the first year remain centered in the western Pacific, given its particular focus on tracking Chinese submarines (see previous AEI coverage of tensions with China over LFAS surveillance).  Only four missions are planned in other areas, and all these will take place in north and south of Hawaii. The Navy has four ships outfitted with the SUTASS-LFA sonar; three (USNS Victorious, Effective, and Able, seen at left, appear to be based in the Pacific, and one (USNS Impeccable) in the Atlantic; each ship could operate for up to 240 days and transmit SURTASS LFA sonar for up to 432 hours per year (the ships transmit sound roughly 7.5% of the time they are operating).

The Rule and the Letters of Authorization allow the Navy to cause temporary behavioral effects (a “Level B Harassment,” defined as animals hearing the low-frequency sonar at levels ranging from 120-180dB, possibly changing their behavior) on 94 species, with no more than 12% of any regional stock of each species being exposed to the sonar in any given year.  The Navy anticipates, based on species abundance in each of the eleven designated operational areas for the first year, that for most species, the percentage will be far lower: usually well under 1% and topping out at 3% for a handful of species in the 9 western Pacific operational areas; around Hawaii, several species will see 1-3% of the population having behavioral impacts, with a handful of species topping out at 6-7%.

Few animals are expected to be close enough to be injured, and the Navy and NMFS presume that physical harm (Level A Takes) will be avoided completely thanks to various mitigation measures, including marine mammal observers, passive acoustic monitoring, and power-downs when whales are close.  But given the uncertainties, NMFS is authorizing injurious or lethal takes of up to 31 whales and 25 seals and sea lions.

The previous five-year LFAS permits, issued in 2007, faced a court challenge based largely on the ways that the Navy and NMFS designated offshore biologically important areas (OBIA), and on the idea that nearshore exclusion zones should extend at times beyond the 12 nautical mile zone covered by those permits.  Most designated and potential Marine Protected Areas (340 of 403) are already within 12 nautical miles of coasts, so are protected from high-intensity ensonification; a more thorough examination of the rest led to the inclusion of one additional OBIA in this round of permitting, with two more being monitored for possible inclusion as more research is done in them (many were omitted because the species of concern in those areas are high- and mid-frequency vocalizers, and LFAS sounds will have more of an effect on larger whales that hear lower frequencies).  A total of 22 OBIAs are designated worldwide, some considered important year-round, and some seasonally.  Sonar sounds must be below 180db within an area extending 1km beyond the boundaries of the OBIAs (thus aiming to keep sounds under 175dB within the OBIAs); likewise, the same 180dB maximum will apply at the boundary of the 12 nautical mile coastal zone.  The Federal Register notice of the Final Rule contains many pages of comments from the NRDC, Marine Mammal Commission, and others, along with responses from NMFS.

Aggressive offshore wind energy plans in Germany are pioneering innovative new approaches to reducing the noise impacts of wind turbine construction, according to a recent Bloomberg News article.  It’s a good, long piece, well worth a read.  A few highlights:

“Quite a large proportion of our sea area will probably be used for offshore wind farms,” said Hans-Ulrich Rosner, head of the Wadden Sea Office for WWF in Germany. “This will have a serious impact on nature, which needs to be mitigated.”  Harbor porpoises, common in the North and Baltic Seas, appear to be especially sensitive to noise, adding to the challenges. 

Construction of the 108 MW Riffgat offshore wind project is nearing completion; it’s been utilizing a double-walled, water-filled casing in which bubbles are produced to absorb some of the sound from pile-driving of the turbine foundations into the seabed.  In addition, a less intense vibration method is being used for almost half the depth of the piles, with the louder hammering of classic pile driving being used for only the last 40 meters.  These noise reduction techniques amount to half of one percent of the total cost of the wind farm.

Germany’s Federal Maritime and Hydrographic Agency, or BSH, has set a noise limit of 160 decibels for 750 metres around offshore wind construction work. Developers regularly overshoot the limit, which is not applied to detonating old bombs, the BSH’s Christian Dahlke said.  “Our regulations are creating a new industry,” Dahlke said. “If environmental rules to protect animal life are tightened in other countries as well, our companies may even export these technologies.”

At the Nordsee Ost project, a large hose perforated to produce a curtain of air bubbles around each of the 48 turbine foundations to absorb the noise from pile driving, which “brought the noise level much closer” to the 160 decibel cap.  But RWE, a utility involved in the project, said that more research and development is needed “to meet the limit reliably in the future.”

The latest paper to be published by the research team that’s been studying noise levels in and around the Stellwagen Bank National Marine Sanctuary concludes that in the waters off Boston, increasing shipping noise has reduced the area over which whales can hear each other to about one-third of what it used to be.

“We had already shown that the noise from an individual ship could make it nearly impossible for a right whale to be heard by other whales,” said Christopher Clark, Ph.D., director of Cornell’s bioacoustics research program and a co-author of the work. “What we’ve shown here is that in today’s ocean off Boston, compared to 40 or 50 years ago, the cumulative noise from all the shipping traffic is making it difficult for all the right whales in the area to hear each other most of the time, not just once in a while. Basically, the whales off Boston now find themselves living in a world full of our acoustic smog.”

Below: Ship tracks for one month, in and out of Boston; Stellwagen Bank National Marine Sanctuary outlined in white, bottom-mounted recording units in yellow. (Graphics from NOAA’s Passive Acoustic Monitoring website)

“A good analogy would be a visually impaired person, who relies on hearing to move safely within their community, which is located near a noisy airport,” said Leila Hatch, Ph.D., NOAA’s Stellwagen Bank National Marine Sanctuary marine ecologist. “Large whales, such as right whales, rely on their ability to hear far more than their ability to see. Chronic noise is likely reducing their opportunities to gather and share vital information that helps them find food and mates, navigate, avoid predators and take care of their young.”

Nine hours in Stellwagen:

Kathy Metcalf of the Chamber of Shipping of America said her group has no doubt noise is increasing and affecting the whales. But measures such as slowing down ships or retrofitting them with new, more efficient propellers are costly and may not even work, she said. A better remedy would be devising and incorporating quieter designs in the hulls and propellers of new vessels.  “We’re kind of a slow industry,” Metcalf said. “But the bottom line is if we could do something now that can be used as guidelines for new construction, 15 years from now, half the world’s fleet would have already been built that way.”

Bonus:  2010 Science magazine audio interview with Leila Hatch, lead author of the new paper.

Ongoing acoustic research in the Mediterranean has confirmed earlier indications that fin whales are far more affected by oil and gas exploration noise than has long been assumed. Manuel Castellote’s most recent paper details a set of disturbing findings, here summarized by the website Science Codex:

Maritime traffic and geophysical exploration –including the search for hydrocarbons– “drastically” reduces the song effectiveness –linked to reproduction and which propagates hundreds of kilometres beneath the Sea– of the whales, which are also the group of marine mammals with the greatest acoustic sensitivity at low frequencies. “The noise generated through human activity in the oceans leads to possible chronic effects on the health of this species”, Castellote states.

After analysing 20,547 hours of recordings of the sounds emitted by the whales, the study published in Biological Conservation indicated that the whales modified the characteristics of their songs in order to try to reduce the impact of noise on their propagation. In addition the researchers recorded a massive displacement of fin whales, triggered by the noise from geophysical prospecting at a distance of 285 km from the study area. “These recurrent displacements, together with the changes in acoustic behaviour, could increase the energy expenditure and reduce the reproductive success of whales affected by the noise”, the expert indicated.

In the long-term the consequences for these mammals are clear: chronic effects which impact on their survival emerge. “Noise in the marine medium, despite being recognised as a significant pollutant, is far from being controlled and regulated within the waters of the Exclusive Economic Zone of Spain”, warns Castellote