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Vermont PSB proposes stricter sound standards

Wind turbines 1 Comment »

Vermont’s Public Service Board has released a draft of new rules for wind turbine siting which embraces a happy medium approach that should minimize adverse effects from noise, while providing wind developers the option of negotiating participation agreements with neighbors who are willing to live closer to turbines than the rules would stipulate.

Current Vermont wind projects are required to keep noise at non-participating homes lower than 45dB outside and 30dB inside; this inside/outside distinction has become a primary bone of contention (especially in summer with open windows), and some sound monitoring has found occasional periods in which noise was slightly above the limits.  45dB is a widely-used noise limit, though it’s also a level at which noise can be quite prominent and disruptive at times.

The new draft rule adopts a fairly precautionary approach, in line with some of the stricter rules that have been appearing elsewhere in places where turbine noise has triggered discontent: the PSB calls for a daytime limit of 42dB and a nighttime limit of 35dB, measured 100 feet from non-participating homes.  In addition, Read the rest of this entry »

Warming spurs new 400km undersea sound channel in Arctic

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

Beaufort icebreaker cropIn yet another unforeseen consequence of global warming, scientists have begun charting the extent of a new underwater sound channel in the Beaufort Sea north of Alaska. As recently as the 1970’s, the water here was coldest just below the ice, but in recent decades two warmer layers have developed, one in the first 50 meters of water, and the second at around 200 meters deep.  Since sound in water tends toward the coldest layers, it used to be dissipated by the rough bottom side of the ice, but now it’s reflected between the warm layers and travels much farther. Research in 2014 and 2016 documented sound transmission across 400 kilometers (250 miles), four times farther than before the emergence of this channel, dubbed the Beaufort Lens.

The near-surface has been warmed by an increased flow of meltwater from rivers and by larger ice-free areas exposed to the sun; this slightly warmer surface water has long been present in summer, but used to disappear in winter.  Meanwhile, warmer waters entering the Beaufort from the North Pacific through the Bering Strait (and perhaps even from the Atlantic, through northern Canada) have contributed to the growth of the deeper warm layer. As is the case for most ocean noise research, the US Navy is a key funder; they’re interested in how increased noise transmission might “dramatically impact the effectiveness of sonar operations.”

The full extent of the Beaufort Lens sound channel is not yet known; further research is planned in the spring of 2018. The area affected is likely to vary with annual changes in the influx of warmer waters and to expand over time as longer-term climate change progresses. Increased shipping traffic is projected to be a major factor in rising ocean noise levels in the Arctic over the coming decades; oil and gas exploration could add to the din if the offshore oil industry rethinks its abandonment of these waters in recent years. In addition, general background noise in some areas could also increase thanks to longer-range transmission of whale calls, which have always been one of the primary sources of ambient sound in these waters.

Vancouver reduces harbor rates for quiet ships

News, shipping No Comments »

The Port of Vancouver has enacted a new incentive program to encourage tankers and other ships to adopt noise-quieting technologies.  Beginning on January 1, 2017, ships that have achieved any one of three widely recognized noise-reduction criteria will receive a 47% discount on harbor fees. Ships that have adapted wake flow or cavitation noise technologies will receive a smaller 23% discount.


This is great news, and we encourage other ports to follow in Vancouver’s enlightened footsteps. It is entirely possible to stop the steady increases in global shipping noise, and even to reverse these trends of the past few decades. Twenty years from now, our oceans can be quieter than they are today, and the isolated pockets still free of humanity’s noise footprints could expand, providing new hope for the world’s ocean creatures.

Much ado about not much in Obama’s offshore oil bans

News, Ocean, Seismic Surveys No Comments »

While I was certainly glad to hear that President Obama has declared most of the Chukchi and Beaufort Seas in the Alaskan arctic “indefinitely off limits” to oil and gas development, the roar of approval from the media and environmentally-minded public was louder than the action actually merits. And the Atlantic withdrawals appear next to meaningless. I know we should never look a gift horse in the mouth, but even a quick glance reveals more gum than enamel in this one. Nonetheless, I’ll take an over-enthusiastic celebratory shout over even the fading ghost of the chance of much more enduring and disruptive roars from seismic surveys, crazy-loud engines on stabilized drilling platforms, and decades of crew transport and tanker traffic. It’s not for nothing that diverse group of scientists and activists have been calling on Obama to do just this for the past couple of years.

Still, I’m here to temper the joy. Before looking at the maps that put the modest impact of this move in perspective, there’s a red flag right up top that deserves a bit more clarification. All commenters, enviros and energy companies alike, seem to agree that this withdrawal is more consequential than the November announcement by the Department of Interior that no lease sales would be offered in either the Arctic or Atlantic for the upcoming 2017-2022 leasing period, a decision that’s won’t be finalized until July and could have been vulnerable to reversal by the incoming administration. Obama’s new declaration likely closes the door on such a rapid reconsideration of these upcoming five-year plans. But notice that the magic word in the withdrawals is “indefinitely,” not “permanently.” It seems that the door is left open to reconsideration: the White House statement detailing the withdrawal states that the “indefinitely off limits” designation is “to be reviewed every five years through a climate and marine science-based life-cycle assessment.” (To be fair, the text is somewhat ambiguous as to whether this 5-year review applies to both the US and Canadian actions, or just the latter.)

UPDATE, 1/11/17: The outgoing administration tied up a worrisome loose end this week by denying six pending applications to do exploratory seismic surveys in the Mid- and South-Atlantic planning areas. This is a one-time denial; future re-applications can be considered at any time. New surveys will be necessary to inform any future lease sales in these areas.

So for now, let’s celebrate that at least the first term of a Trump administration has its hands fairly well tied in its ambitions to expand US offshore oil production from its current focus on the Gulf of Mexico and in a 200 mile strip of waters along Alaska’s Arctic coast. Wait, what’s that? Yep, the big withdrawal announcement doesn’t remove any of the areas already being actively developed off Alaska’s northern shores (brown in this map):


The good news is that there are currently only a handful of producing wells in that brown strip, on three of the five lease areas owned by one company, Hilcorp, just offshore from Deadhorse (they’re the tiny green areas in the next map, below). In fact, out of the peak of 480 lease tracts in the Chukchi and Beaufort Seas that had been acquired by energy companies as of 2008, only 43 leases (including 53 lease blocks) are still even nominally in the planning pipeline; 42 of them are in this area that remains available to future leasing as well. Falling oil prices, disappointing test well production, and both logistical and increased regulatory hurdles have led many of the companies that were once so enthused about moving into these waters to formally abandon their leases.

Here’s a look at where things stood as recently as July 2015, when the Chukchi was still the focus of industry hopes and dreams: Read the rest of this entry »

Good news and bad news on BC shipping traffic

Ocean, shipping No Comments »

British Columbia has been a hotspot of concern—and research—about the extent and the impacts of shipping noise. The southern BC coast is close to acoustic saturation, with any increase in noise having the potential to completely overwhelm the underwater soundscape; meanwhile the northern coast holds a few areas that are still nearly free of human noise intrusion, and we need to do all we can to preserve these increasingly rare acoustic refuges. These contentious waters have been roiled in several contradictory though perhaps ultimately productive ways by recent Canadian government actions. In the month between Thanksgiving and Christmas, a northern pipeline was rejected and a southern one approved; meanwhile, ongoing research aims to identify the noisiest ships and help inform new regulations that could reduce overall noise levels.

bc-tanker-vanc-to-burnabysmThe biggest headlines and fears have been spurred by the final approval of the Trans Mountain Pipeline expansion that will deliver oil from the Alberta tar sands to an existing port in Burnaby, BC. The port currently hosts about five tankers a month; the increased flow in the expanded pipeline (75% the capacity as the proposed Keystone XL) will necessitate about 35 ships a month, meaning an average of two tanker transits a day past Vancouver as they travel to and from the Strait of Georgia off the coast. These waters are currently burdened by shipping noise 85% of the time, and the increased traffic will push this to 100% in some areas. Concern centers on the tenuous status of the region’s orca populations, which are struggling to find the salmon they need; shipping noise makes it harder for them to track salmon with their echolocation clicks and to communicate with each other as they search for food. “Death by a thousand cuts, and this is a very deep cut,” says Deborah Giles, research director for the Center for Whale Research. “They’re spending more energy to find less food and we’re adding the equivalent of a rock concert,” she says. “These whales will not survive.”

Environmental groups will likely file suit challenging the approval, citing the government’s failure to mitigate the increased impact. At the same time, though, Fisheries Minister Dominic LeBlanc and Transport Minister Marc Garneau are working on a revamped recovery plan for the 80 remaining resident orcas.  LeBlanc notes that  Read the rest of this entry »

VT towns reject wind farm & town-wide personal payments

Human impacts, News, Wind turbines No Comments »

Two central Vermont towns have voted against plans to build a wind farm on the hills along their border, despite a late-in-the-game offer from wind developers to mitigate some of the downsides by making direct annual cash payments to residents. While landowners that host turbines always receive payments from wind developers, and some projects have included “good neighbor” payments to nearby landowners, this is the first time I know of in which a project extended a cash-payment program to include all local citizens.*

The votes were not close, with over 60% of voters in both towns giving thumbs-down to the wind farms. Iberdola, the developer, had pledged to respect the voters and discontinue its efforts to build there if they lost.

A key factor for many locals was the unusually high number of homes relatively close to the ridge where the turbines were slated to be built (click image to enlarge). As compared to two other large projects in the state (Sheffield and Lowell Mountain), this project had a concentration of homes close enough to more or less guarantee that the turbines would be easily heard regularly—over a hundred within a mile, and another 150 between a mile and a mile and a half. This increased home density (4-6x more than Sheffield or Lowell) continued out to 2 miles, where noise could be audible at times.

What to make of the payment offers?
While many locals took offense at what could easily be seen as an attempt to buy their votes, the cash payments plan was also a long overdue acknowledgement that the presence of turbines in a community does amount to a “dis-amenity,” a negative contribution to local sense of place and quality of life. Read the rest of this entry »

5th vote in Dixfield retains embattled wind ordinance

Default, Human impacts, News, Wind turbines No Comments »

ME Timberwinds~Dixfield-2mi simulationYou really need to have a history degree to keep track of the twists and turns in the 4-years-and-counting Dixfield Wind Energy Saga. Ever since the adoption of a wind ordinance in 2012, local citizens, Planning Board, and Selectmen in this Maine town have been proposing revisions that have been rejected by voters.  The 2012 ordinance, which still stands, includes a 2000-foot setback and noise limits in accordance with state standards of 55dB day/42dB night.  In both 2013 and 2015, the updated ordinances contained some stricter standards (both include low-frequency standards and the 2015 one would have doubled the setbacks and lowered the night noise limit to 35dB), but both times the voters narrowly rejected the changes. Local officials have remained concerned that some of the zoning language in the 2012 ordinance is unenforceable, and this spring, they once again took a shot at finding a middle ground by resubmitting the language they liked in the 2015 attempt, but tweaked to return the noise limits to the state standard; as one Planning Board member put it, “The vote on the proposed wind power ordinance has provisions that both sides dislike. Maybe that makes it a reasonable compromise.”  But that, too, failed to win support in a June 2016 vote. These 2012-2016 votes were all narrow victories for the pro-windfarm contingent in town, which maintained that the setbacks would preclude development and the low-frequency noise requirements would require cumbersome monitoring.

Now a 5th vote in November 2016 has once again rejected a change, this time a proposal to simply nullify the 2012 town ordinance and let the state regulate the wind farms, which is now the preferred option by those who want the town to get out of the way and let the wind farm proceed. It was once again very close, 616-642 (14 switched votes would have changed the outcome), and I guess it marks the first loss by the pro-wind group, but no one will be happy with the outcome—local officials still say the 2012 version is unenforceable and advocates for greater local control have repeatedly pushed for more stringent standards.  So the merry-go-round will continue spinning, the gold ring still out of reach for all concerned.

For a recap of the tortured history, click on through to read the post I put together in June 2015 recounting the events up till then—including, in fact, a vote recount that dramatically overturned the one previous victory by the more cautionary contingent.

Read the rest of this entry »

Not OK!—Military jets mar Olympic National Park wilderness experience

Human impacts, News, Wildlands No Comments »

Pat McMahon says it so well that I’ll simply reprint this letter to the editor, published in the Peninsula Daily News:

LETTER: Jet noise takes away from natural beauty
Olympic National Park has lost a vital component with the persistent sounds of jets overhead.

Many of us visit national parks as a way to balance the rigors of everyday life with an experience of wilderness and solitude.

During the last week of June, while participating in the annual sea otter census near Hoh Head north of the Hoh River, my colleague and I experienced persistent and loud military jet noise.  The noise would suddenly erupt as the aircraft transitioned from land to sea. One of the abrupt sounds echoed such that we thought we might be experiencing the beginnings of a landslide. During the three days I participated in the sea otter census, we experienced persistent, loud jet sounds most of the day.

One week later while backpacking with my grandchildren at Toleak Point, we experienced the same persistent, loud jet noise. It was not what I was expecting on a coastal wilderness hike in Olympic National Park.

We have suffered a loss in Olympic National Park, where you will no longer be able to get lost in the natural sounds of moving water and marine animals. When you least expect it, the loud sounds of military aircraft will take you away from peacefulness and remind you of the reality of everyday life. There are over 7 billion humans on our planet now, and we need quiet natural places more than ever. Someplace to go where your spirit can regenerate.

It is so sad that we have lost this component of Olympic National Park.

Pat McMahon,
Sekiu, Washington

Humpback bottom-feeding is (somewhat) affected by shipping noise

Ocean, Science, Sonar No Comments »

AEI lay summary of:  Blair HB, Merchant ND, Friedlaender AS, Wiley DN, Parks SE. 2016. Evidence for ship noise impacts on humpback whale foraging behaviour. Biol. Lett. 12: 20160005.

Sand lance 350pA new study looks for the first time at the impact of human noise on an important type of humpback whale foraging activity, bottom-feeding on sand lance.  The research took place in the Stellwagen Bank National Marine Sanctuary in the southern Gulf of Maine, where humpback whales routinely do deep dives at night, rolling to their sides when they reach the bottom to forage for the small fish.

To assess the whales’ responses to human noise, D-Tags were placed on ten individuals over the course of two years.  These temporary suction-cup tags record received sound levels that the animal is hearing, as well as tracking the details of their dives.  The tagged whales made 218 dives, 83 with ship noise exposure and 135 without ships nearby.

Here’s an example of the sort of picture that the D-tags can provide:

Blair 2016 Humpback side roll Dtag track plot

The results show a 29% decrease in the number of “bottom side-roll feeding events” as the received level of the ship noise increased, as well as a 13-14% decrease in both the descent and ascent rate of the dives.  Interestingly, the increase in received noise level was rather small overall (received level was higher when ship noise was present, but not statistically significantly higher), perhaps indicating that the ships were, on average, not all that close.  As is typical, the team used advanced statistical techniques to tease out modest effects from the subtle and varied data. (In case you’re wondering, they used “linear mixed-effects models” with data “square root transformed to approximate normality,” then calculated effects by “summing Akaike weights of all models.” Sounds good to me!)

The raw numbers put the effects into some more straightforward perspective.   Read the rest of this entry »

Belugas struggling in Cook Inlet, St. Lawrence rivers

Bioacoustics, Ocean, Science 2 Comments »

Two troubling reports have surfaced regarding beluga whale populations in waters that have become increasingly industrialized and noisy in recent years.  In Quebec’s Saguenay River, the major river system draining into the St. Lawrence, recent years have seen a sharp uptick in dead beluga babies and pregnant mothers; in 2015, these sensitive individuals were half of all known mortalities.  Increased noise is the primary culprit; according to the CBC, “The researchers are working from the theory that beluga calves have soft calls, which may be drowned out by the noise from ships, ferries and boats in the Saguenay and St. Lawrence rivers.”

In Alaska’s Cook Inlet, beluga range has shrunk dramatically over the past couple of decades (see map below), and accelerated in recent years, as ongoing port construction and oil and gas development has introduced increasing levels of noise into these key waters.  It’s unclear whether the smaller range is simply a reflection of a reduced local population, meaning they don’t need to range so far to avoid competing with each other for food, or if they are responding to the increasing chronic noise.  See previous AEInews coverage of the Cook Inlet belugas here.  Recent NMFS research papers on the changes can be accessed at this link, and this in-depth article from a couple years back is a good overview of the current development and research activities.

Beluga range Cook Inlet 1978-2014

Marine invertebrates also affected by ocean noise

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

Some of the most interesting new work in ocean noise is revealing the myriad ways that humanity’s sounds can have negative impacts on ocean life other than marine mammals.  Sure, everyone loves our warm-blooded kin, but there’s way more to the ocean ecosystem than dolphins, humpbacks, and seals.  AEInews has been covering this leading edge for years (see these posts on shellfish larvae, crabs, and squid).  Recently, at the triannual Effects of Noise on Aquatic Life conference, held this year in Dublin, a slew of new papers revealed further concerns.

blue-banded_hermit_crabThis post from NRDC summarizes the highlights.  One of the most striking findings was that 6 hours of shipping noise can damage the DNA in the cells of mussels, perhaps due to a stress response; similarly, protein structures in the sensory cells of cuttlefish were damaged by low-frequency noise.  These would be some of the most profound impacts yet discovered; note, though, that the brief summary here does not specify the sound levels—some research on health effects use much higher exposures than are likely in the wild, as a way of identifying possible effects for further study at lower exposure levels.  Other new studies followed on previous ones that suggest many animals respond to noise as if it were a predator; these responses often suggest increased stress, and are waste of precious energy, or disrupt feeding.  Also of note is a one-off anecdotal observation (not yet studied systematically) of a hermit crab exiting its shell after exposure to low-freqency sound; it appeared to be examining its shell, perhaps trying to determine the source of the disruption, or checking for physical damage. While out of its shell, it would be vulnerable to predation.

All this new research is both exciting, as it reveals the vast and subtle role of sound in the natural world, and sobering in facing us with the widespread consequences of our heedless sonic intrusions into wild ecosystems.


New court ruling on Navy sonar has big implications

News, Ocean, Sonar No Comments »

A new court ruling could fundamentally change the standards that the Navy and National Marine Fisheries Service have been using to regulate Navy sonar, by requiring more areas to be set aside as off-limits to the Navy’s routine peacetime operations.  A federal appeals court has ruled that simply determining that Navy activities will have “negligible impact” on populations is not sufficient; regulators must also, and separately, set standards for sonar use that assure the “least practicable adverse impact” on marine mammals and their habitats.  (Download the ruling; it’s only 35 pages, not a bad read!)  As those who have been following the evolution of the NMFS’s ongoing cycle of five-year authorizations for Navy activities will know, the routine procedure has been to dutifully tally the numbers of animals that may be affected—generally they predict relatively few injuries or deaths (more when explosives training is involved), as well as behavioral effects on millions of animals—and then to determine that the long term effects on each species’ population levels will be negligible.  This negligible-impact finding then allows NMFS to issue permits allowing for the predicted effects.

NMFS has been presuming that negligible impact is sufficient to also satisfy the requirement for “least practicable impact.”  Their basic argument was that you can’t get a lower impact than negligible.  However, there were a couple of flaws in this approach.  First, the threshold for population-level effects in this permit was presumed to be 12% of the regional population of any given species being able to hear, and have their behavior potentially changed, by sonar transmissions; clearly, there IS room to reduce this degree of impact.  But more importantly to this court, the NMFS’s approach to determining what areas are “biologically important,” and so worthy of some protection from routine sonar operations, was found to violate the “least practicable impact” standard—and it appears that designating more protected habitat will be essential to meeting this standard.

Note: This court case concerns the SURTASS-LFA low-frequency active sonar, currently deployed on four US surveillance vessels, rather than the mid-frequency active sonar that has been the focus of most of the previous legal wrangling.  This LFA lawsuit challenged routine, peacetime use of the sonar worldwide; by contrast, all the mid-frequency challenges up til now have only sought to constrain testing and training activities in Naval training ranges off the US coasts, not its widespread routine use by over a hundred Navy ships around the world.  So this case has a limited immediate scope, though the underlying theme of setting aside more areas as off-limits is a core element of all the sonar and naval training legal challenges, and this new clarification by the courts on the separate requirement for “least practicable impact” could apply to all NMFS permitting.  

This court ruling does not prescribe a new management plan; it merely found that the current one does not meet the letter of the law.  This case is now remanded back to the district court for further deliberation.  However, we are approaching the end of the 5-year authorizations that have been challenged here (2012-2017), so the most likely consequence of this ruling is that the NEXT round of authorizations, due in 2017, will need to take more care in meeting the “least practicable impact” standard, either by expanding the areas off-limits to sonar, or by more adequately justifying why NMFS feels they are meeting this standard in other ways.

An apparently deciding factor in the court ruling was a 2010 white paper written by four NMFS “subject matter experts,” Read the rest of this entry »

Wind farms increase stress in nearby badgers

Effects of Noise on Wildlife, Science, Wind turbines No Comments »

Lay summary of
Rosanna CN Agnew, Valerie J Smith, Robert C Fowkes.  Wind Turbines Cause Chronic Stress in Badgers (Meles meles) in Great Britain.  Journal of Wildlife Diseases, 52(3), 2016. DOI: 10.7589/2015-09-231.  Download PDF

A new study out of Britain provides one of the clearest looks at whether wind farms create chronic stress in wildlife populations.  The results are striking—badgers living near turbines had stress levels 265% higher than the control groups—though not yet conclusive.

The researchers used what appears to be a very solid study design, testing cortisol levels in badger hair among 25 badger “setts” (dens, occupied by one or more badger families) separated into two groups: 9 “affected” setts were within 1km of wind farms, and 16 control setts were more than 10km from any wind farm.  They made an effort to assure that control setts were comparable in their habitat types, distance from roads, and geographic spread across Britain.

Agnew 2016 badger cortisol 1km and controlThe overall results are fairly clear-cut.  Here’s a graph of the two groups; the boxes show the 3 quartiles of results in each group (the bottom of the box being the level that 75% of the animals were above; the line across the box showing the level where half the animals were above, half below; and the top of the box the level that 25% of the animals were above), with the bars outside the box showing the remaining scatter of individuals.  The mean among controls was .87, and among the affected group the mean was 3.16

Agnew 2016 badger cortisol and distanceA closer look at the results suggests that, as usual in field studies, there is a lot more going on than the means and medians suggest.  Here we see a plot of the 9 affected setts, with distance to nearest turbine on the bottom axis.  Interestingly, there is a wide scatter of results, with some setts (2 of the 9) showing levels very similar to the controls, about half (4 of the 9) having somewhat elevated levels, and only 3 setts being highly elevated, above the highest of the control setts.  Our first image shows this skew, with the upper quartile of the affected box stretching far above the middle line (and thus pulling up the mean to a significant degree).

This skewing does not invalidate the results; such scatter is very typical of most impact studies.  But it does remind us that there is rarely a simple, universal cause-and-effect.  The authors address many factors that could have contributed to anomalous results, and consider most of them to be quite unlikely; as they summarize, “Although certain intrinsic factors, such as sex, age, and disease status, have been thought to influence cortisol levels, it is very unlikely that the 264% cortisol increase experienced by affected badgers is a result of these factors alone.” Still, these and the other possible confounding factors will deserve closer scrutiny in followup studies.

The authors presume that vibration and noise, and likely infrasound, are the primary stressors, but did not do sound measurements as part of the study.  There was no mention of whether badgers are stressed by tall structures, as some small mammals are (due to predation by hawks).  While it seems likely that badgers are too large to be at risk from above, some confirmation of this would have been helpful to add, if true.

The researchers suggest that their results could have implications for controversies about humans who have reported negative reactions to wind farms, noting that badger hearing range is similar to humans.  A final finding was that the badgers did not appear to acclimate to the wind farms: setts near new wind farms had only slightly higher stress levels than those near long-established ones, where the mean remained well above that of the controls.

AEI presentation at Ecoacoustics 2016

Bioacoustics, Effects of Noise on Wildlife, Ocean, Science, Wildlands 1 Comment »

I recently returned from the 2016 Ecoacoustics Congress, the 2nd meeting of the new International Society of Ecoacoustics, held this year at Michigan State University in Lansing. It was a very informative gathering of fascinating researchers from around the world; several traveled from Australia, a couple from Taiwan, many from Europe, and some from South America. I’ll add more here soon about this rapidly-advancing field, but for now, I wanted to quickly post a PDF version of my presentation:

Saving High-quality Acoustic Habitat: Identifying areas of relative natural quiet by Jim Cummings

Top researchers urge US to hold off on Atlantic seismic surveys

Bioacoustics, Ocean, Ocean energy, Science, Seismic Surveys No Comments »

Oceana Right Whale map250WEBIn a second letter to the Obama administration, 28 top ocean noise and whale researchers have raised serious concerns about planned seismic surveys along the east coast of the U.S.  The scientists cite several recent studies that shed light ways that the long term health and reproductive rates of right whales have been affected by temporary stresses, and suggest that the planned seismic program could push this extremely endangered species over the edge.  With only 500 individuals remaining, the loss of each individual creates a significant impact on long term population viability.  According to the letter,

Notably, according to analysis by the New England Aquarium, even a small decline of only ten percent in right whale health can impair reproduction or eliminate it entirely. A newly published study shows that a population-wide deterioration in North Atlantic right whale health from 1998 to 2000 was correlated with a drastic drop in calving rates, further indicating that factors influencing health can be responsible for suppressing reproduction.

With previous studies showing noise causing lasting stress in right whales, and that whales that have been through an entanglement experience with fishing gear show lasting health effects and reduced reproduction, the researchers conclude:

In light of the desperate level of endangerment of the North Atlantic right whale and the serious consequences of entanglement, it is critical that other major stressors are minimized or removed to ensure the recovery and long-term survival of this species. The additional stress of widespread seismic airgun surveys may well represent a tipping point for the survival of this endangered whale, contributing significantly to a decline towards extinction.

A year ago, 75 scientists wrote to the Obama administration to urge them to reject plans for seismic surveys and oil and gas development along the Atlantic seaboard.  In March of this year, plans to offer drilling leases for the five-year period 2017-2021 were abandoned.  A future administration may re-open the area for later five-year planning periods, and the oil and gas industry wants to conduct new surveys in the meantime.  Currently, four companies have applied to the Bureau of Ocean Energy and Management (BOEM) for permits to conduct surveys in the Atlantic (see maps above and below).  This new letter from 28 of the same researchers who wrote last year asks the administration to follow up its announcement to keep the Atlantic closed to drilling, by now also withdrawing the 2014 decision to open the area to new surveys, in the light of the new research that is not included in the previous environmental impact statement—or at the very least, to refrain from issuing any permits until after NOAA’s planned 2017 right whale status review, which may confirm whether recent slowdowns in the species’ population growth have continued.

The NRDC elaborates on the expertise of these researchers:

The statement is signed by some 28 marine biologists with particular expertise on the right whale, from such institutions as Cornell, Duke, the New England Aquarium, Wildlife Conservation Society (the conservation arm of the Bronx Zoo), UNCW, and Woods Hole Oceanographic Institution. For right whales, it doesn’t get much more authoritative than this.

The map at the top of this post highlights designated right whale Essential Habitat (red) and Seasonal Management Areas (blue cross-hatches).  Note that the areas largely overlap; this duplication of effort and noise is among the concerns expressed by regional and national ocean advocacy organizations; oil and gas exploration companies routinely duplicate each others’ surveys, with everyone’s data being held as proprietary information.  The larger map below shows designated Essential Habitat for a wide range of Atlantic species.  One of the proposed survey areas is well offshore, fifty or more miles from the key right whale habitat, while the other three come right to the edge of the designated habits, or even overlap with them.  Seismic survey sounds can routinely extend for tens of miles from the survey vessels (and up to 1500 miles in deep offshore waters), so concerns about increased stress—especially in the nursery areas along the southwest coast—apply to all the proposed survey areas, if they take place when whales are present.

For more from the researchers involved, see this press release that includes several quotes, and for more on the maps, produced by Oceana, see this article from the Coastal Review and this page on Oceana’s website.

Oceana Essential Habitat Map Atlantic500WEB

Taming ship traffic in the warming Arctic

News, Ocean, shipping No Comments »

Ship traffic through Canada’s Northwest Passage has more than doubled since 2004 and tripled since the 1980s, mostly thanks to much longer open-water seasons as the Arctic continues to warm.  Today’s 300-350 voyages per year is expected to double again as both mining and tourism rise in the years ahead.

In response, there are increasing calls to manage the increased ship traffic, both to improve safety and minimize environmental impacts.  A new report from Pew Charitable Trusts draws on recent data, previous Canadian government reports, and First Nations concerns to make the case. “Corridors give people a roadmap to follow,” said Louie Porta, one of the report’s authors. “A robust corridor system is a recommendation for vessels to stick to a very, very small portion of the Arctic waters as opposed to now, where there are no limits – vessels can basically go wherever they want.”  The map below shows 2014 ship tracks criss-crossing key biologically important areas in the western part of the Northwest Passage; here’s a link to the full map.

Pew report-2014 ship tracksCROP

According to an in-depth article on the excellent new website Arctic Deeply:

Government and Inuit groups have identified at least 38 areas of ecological and biological significance (EBSAs) occupying nearly 50 percent of Canadian Arctic waters. “There’s a high concurrence of vessel traffic patterns and areas of biological significance. We can’t say that ships can’t go where the environment is significant, but it’s possible to create a more flexible, dynamic policy that identifies what times of year ships can be in certain locations,” said Porta. . . . Under the proposed framework, shipping corridors would be identified by integrating human and vessel safety, environmental protection and Inuit rights.

The Canadian Coastguard has been working on a similar plan to concentrate shipping traffic.  However, their current proposal for the Beaufort Sea allows shipping in 45% of regional ecological, biological and Inuit areas of significance, while the Pew report’s recommended lanes overlap just 25% of these key areas.

Arctic shipping is a much bigger issue than just the Northwest Passage.  Arctic Deeply has been quick to dive into this important topic, including a recent piece on the impact of Arctic shipping noise on whales, and a long Q&A with a geographer who focuses on climate change and the Arctic.


Using gliders to listen for whales 24/7

Bioacoustics, Ocean, Science No Comments »

gliderWEBOver the past few years, researchers have developed an increasingly diverse set of platforms for listening in on the world beneath the ocean’s waves.  Now, in addition to recorders deployed in key areas for months at a time and temporary suction-cup acoustic tags on individual whales, a long-anticipated mobile option is moving into more widespread use.  Autonomous gliders offer an enticing combination of attributes: they can operate for weeks or months at a time, exploring a region rather than staying in one place; they can be outfitted with a range of sampling capabilities; and they are relatively inexpensive to build and deploy.  Subsea gliders can dive to 200 meters deep and resurface periodically to transmit data to data centers on shore; they’ve been used for physical sampling of oceanographic data (temperature, salinity, etc.) for many years, but it’s only more recently that acoustic sampling has become common.

The most exciting thing about putting recorders on gliders is that they can operate around the clock, monitoring for whales even in bad weather and at night, when ship-based researchers cannot.  Plus, the cost of operating research ships means that field studies are short and targeted to areas already known to be hot spots for whale activity, while gliders can be used to explore regions that we know less about. In particular, we know that whales tend to move around season-to-season in search of the best feeding opportunities; on the Scotian Shelf in the Canadian Atlantic, some areas that are protected feeding habitat have been largely abandoned in recent years due to lack of prey.  Gliders can help identify where the alternative feeding grounds may be, so they, too, can be protected.

This spring the Canadian WHaLE project (Whales, Habitat, and Listening Experiment) is expanding to the west coast. For three weeks, a six-foot glider will explore waters off Vancouver Island.

“Ocean gliders are a new technique for gaining insights into whale ecology on Canada’s West Coast,” says David Duffus, who leads the west coast project. “Many species of concern under Canada’s Species at Risk Act are termed ‘data deficient.’ We need more information on whale habitats and whale feeding ‘hot spots’ so we can put in protective measures, such as real time whale-alerts for shipping traffic.”

In addition to the longer-term goal of increasing our understanding of changing habitat use patterns, the gliders could also help reduce ship strikes. There is hope that in some especially busy shipping lanes, gliders may offer a new way to let ship captains know when whales are nearby; this is especially important for the critically-endangered North Atlantic right whale.

New maps offer more detail to ocean planners about how animal concentrations change during the year

Ocean, Science No Comments »

An ongoing challenge for ocean regulators has been our relatively coarse understanding of where ocean animals are at any given time.  For many species, we’ve been limited to relatively broad-brush data, such as regional population estimates or having a moderately clear idea about particular feeding or breedings areas, with limited knowledge of where these same animals go at other times of year.  All this has made the crucial task of estimating the impacts of human activities (Naval sonar and explosives exercises, oil and gas seismic surveys, construction of new shipping ports) somewhere between difficult and impossible—leading to a mountain of EISs, agency determinations, and court filings over the question of how best to protect ocean life from our noisy actions at sea. Confounding matters for all concerned, on the matter of protecting key habitat, the Navy has sometimes prevailed and sometimes lost in recent challenges.

Over the past decade or so, several projects have been bringing data together from a slew of historical studies, along with doing new surveys in the field that flesh out our understanding of animal distributions.  These efforts are beginning to bear fruit.

baleen two seasonsWEB500

This week, a team from Duke University’s Marine Geospatial Lab released a series of maps and new mapping tools to the public and to other researchers, making available data they’ve been compiling for use in the current round of environmental analysis for the Navy’s east coast and Gulf of Mexico training ranges, and for inclusion in NOAA’s ongoing Cetacean and Sound Mapping project (also known as CetSound).

In addition to an open-access paper published in Nature Scientific Reports, a set of comprehensive species-specific supplemental reports (each one running to over a hundred pages), and a good layman’s overview using the Story Map platform, the Lab also has an online mapping portal, OBIS-SEAMAP, that displays annual animal densities for marine mammals, seabirds, sharks, rays, turtles, and even a few lizards of conservation concern.  OBIS-SEAMAP—short for the Ocean Biogeographic Information System: Spatial Ecological Analysis of Megavertebrate Populations—archives hundreds of surveys, satellite telemetry datasets, and photo-ID collections, and has now expanded to include long-term archival of species distribution models. Read the rest of this entry »

1st recordings from deepest spot in ocean: whales, typhoon, ships

Ocean, Science No Comments »

challenger deepWEB250A team of researchers from Oregon State University has made the first-ever recordings of what the soundscape is like in the ocean’s deepest spot: the Challenger Deep.  This part of the Mariana Trench is more than 36,000 feet below the surface, but it’s not all that isolated from the normal cacophony of the seas.  As lead investigator Robert Dziak says,

“You would think that the deepest part of the ocean would be one of the quietest places on Earth. Yet there is almost constant noise. The ambient sound field is dominated by the sound of earthquakes, both near and far, as well as distinct moans of baleen whales, and the clamor of a category 4 typhoon that just happened to pass overhead.”

deep graphic WEB500They also heard large ships coming in “loud and strong,” and even the calls of a smaller  toothed whale or dolphin relatively near the surface; you can listen to short sound clips here.  It may seem surprising that sound penetrates so deep.  But of course, seven miles is not really all that far in the ocean; whales routinely communicate over larger distances, and several human sounds sources are readily heard for tens of miles around (or hundreds when caught in a sound-reflecting layer).  What sets the ocean’s depths apart is the extreme density of the water, which can facilitate sound transmission.  Still, it’s a bit disconcerting to realize that no part of the sea is truly free of the acoustic footprints of man.


New gas port proposals adding injury to insult in BC

Ocean, shipping No Comments »

The British Columbia coast is a wild territory, yet one pockmarked with major shipping facilities.  Four related ports stretch down the coast from Prince Rupert, sending coal, grain, and other products to Asian markets and south to the U.S. and beyond.  Canadian First Nations and environmental groups have been raising alarms about the cumulative impacts of increased development in this remote area, while innovative ocean noise research is modeling the ways different species’ listening and communication ranges may be affected by more shipping.

Pacific Northwest LNG and Prince Rupert LNG dredging map -Skeena Wild Conservation Trust Ocean Ecology-850x720Now, plans for two more port facilities, on islands just down the coast from the current Prince Rupert complex, have perhaps gone too far.  These are natural gas facilities, next to and literally on top of the Flora Bank, a primary feeding area for juvenile salmon.  Project proponents stress that their design will avoid damaging the area, but they seem to be discounting the potentially devastating acoustic impact of the bringing huge ships this close to a sensitive habitat.

eelgrass sockeyeSMFlora Bank, in intertidal waters off Lelu Island, contains about 60 per cent of the eel grass habitat in the Skeena Estuary, a watershed that gives birth to 200 million young salmon each year.  This expanse of eel grass is a crucial way station for those that exit out the northern branch of the Skeena (the waterway off the right side of the image above); studies indicate 2-8x more salmon enter the ocean here than in other areas to the south; by some accounts, 90% of the Skeena salmon run comes through here. “It is absolutely clear that Lelu Island is the worst location for such a facility,” says Dimitry Lisitsyn, a Russian biologist who has seen the effects of oil and gas development in his country.

The companies behind the projects are making efforts to minimize disturbance of the seabed by building a raised pier, jetty, and suspension bridge and will fund the establishment of new seagrass beds nearby, with a goal of doubling the number of young salmon being supported—though similar habitat-creation projects have a spotty success rate.  Yet even if they do keep a light physical footprint and avoid creating new sediments that would damage the eelgrass beds, the ships coming into both of the new ports will change the acoustic habitat irrevocably.

Alexander Vedenev, head of the Ocean Noise Laboratory at the Russian Academy of Sciences, says that noise levels from the plant and ships will be audible to young salmon out to about 3km away; some young fish will avoid such sound levels or be startled away with the approach of a ship, while those who linger are likely to experience higher than normal stress levels.  Both stress and reduced feeding time can affect long-term survival rates; the worst-case scenario is an abandonment of this crucial feeding ground. The current Ridley Terminals—and shipping lanes serving the other Prince Rupert ports—are just beyond the 3km range, while the new Prince Rupert LNG facility will be 2km from the edge of the Bank, and the Pacific Northwest LNG facility is right on its edge, thus flooding the entire Bank with noise.

Lelu locationWEB

So here we have a stretch of wild and beautiful coast, already burdened by significant shipping noise and facing the prospect of many other proposed ports, including a big one at Kitimat, in the lower right of the above image.  Now, they want to extend the already-developed stretch of coastline right down to the very edge of an established critical habitat for salmon, building a jetty over the eelgrass itself and dredging a pier area off its outer fringes.  This is indeed adding clear injury to an already-existing insult of prime oceanic habitat where the bulk of the Skeena’s salmon travel to and from the sea.  How much is enough, folks?  Yes, yes, I suppose we could just consider that stretch of coast south of Prince Rupert to be a sacrifice zone; why not extend it right to the lip of the estuary?  And I don’t know the area well enough to say with certainty that the salmon can’t find other areas to feed as they make their initial foray from the inland waters of their birth and out into the wild unknown of the seas….but I can easily look at that map above and appreciate the incredible beauty of such a big, wild river, pouring through the mountains from headwaters deep in the heart of British Columbia.  Why would we want to desecrate its mouth?

HowLoud offers nationwide neighborhood sound maps

Human impacts 1 Comment »

I’ve been following this project since its Kickstarter beginnings, and am pleased to see how well they’ve implemented their innovative idea at  The goal is to provide a standardized measure of community noise levels in cities and towns across the country; they’re up to over a thousand now, including all mid-sized urban areas and many connecting regions of smaller towns in the east and midwest.  Their “Soundscore” is a combination of traffic noise, airport noise, and general hubbub of nearby businesses; it’s all computer modeled, and overlaid on zoomable maps.  Here are a couple of examples:

Screen Shot 2016-02-15 at 4.09.30 PMTroy, NY, a mid-sized college and old industrial town along the Hudson River.  Note the I-787 corridor on the far side of the river, and the relatively rapid drop-off of neighborhood noise as you move away from the core downtown area.


Screen Shot 2016-02-15 at 4.11.12 PMAnd my current home in Kennebunk, ME, in a quiet neighborhood.  You can see the much smaller downtown noise footprint in the lower right, and the more modest highway noise from the Maine Turnpike on the left.

Check out your city or town here!

You can zoom in on these maps to pick out individual homes; part of HowLoud’s financial model is licensing these maps to real estate companies, in hopes that the relative Soundscore may become a selling point for homes in quieter areas.  I can well imagine renters being equally interested in having better idea of where the sounds of a city center begin to moderate a bit.

The folks behind HowLoud have prioritized using a consistent metric nationwide, so that comparisons are valid.  It seems to me that their 100-point scale is slightly nudged toward a suburban tolerance for noise, rather than than a deeply rural baseline.  By that I mean that the dark-blue areas of their maps are probably not as totally free of noise as you may imagine; I’m thinking of the spot not far from my current home in the screenshot above, which looks to rate around 90, and a deeper blue zone in a land trust property in town that appears to be close to 100, neither of which is truly close to noise-free.  I suspect that this may be largely due to the fuzziness of the Federal Highway Administration highway noise model that provides their foundation.  These are based on 24-hour averages, which is practical for assessing impact, but doesn’t reflect on-the-ground experience: the 24-hr average is lower than the daytime peak of traffic noise, but higher than the nighttime average (but again, usually lower than the sound of a single car or truck passing in the night).  The FHA model may also somewhat underestimate sound propagation from roads (for example, that Turnpike in the lower picture is readily audible at night, even in the dark blue zone).

But I’m nitpicking!  This is a fantastic first take on an initiative that we really should extend to include the vast, un-urbanized parts of the country as well.  NOAA is beginning to do these sorts of noise model maps for the world’s oceans, while the National Park Service and other researchers have done some country-wide modeling similar to this project.  I’m all for the potential to use these techniques as a way to target remaining refuges of natural quiet for recognition and protection in the years and decades to come; every little relatively quiet pocket is valuable, and maps like these can help us realize what’s still there, just far enough from roads that we can still experience the landscape on its own terms.



Ohio “wind energy killing” setbacks: reports of wind’s death were greatly exaggerated

Human impacts, Wind turbines No Comments »

windenergygraphicOnce again the wind industry has been caught crying wolf about reasonable and workable setback increases.  In 2014, the Ohio legislature tweaked the state’s wind farm siting standards to require setbacks of 1300 feet from neighboring property lines, rather than from neighboring homes.  Wind energy advocates gnashed their teeth, with an executive of the national trade association, AWEA, claiming that “This would kill further wind energy development in Ohio unless the governor vetoes it,” while the CEO of wind developer Apex Clean Energy chimed in that with such odious setbacks, Apex “will have no choice but to take its investment and its business elsewhere. ”

Get ready for a shock, AWEA: Amazon, not phased at all by the setbacks, has announced plans to build a 100-MW wind farm to power two new distribution centers in Ohio.  And, in a late-2014 review of the status of 11 projects that are in the pipeline, it was federal tax credits and lapsed state renewable energy incentives that were cited as current challenges, not the setbacks.  While it’s quite possible that previously-approved projects are proceeding under the old setback rules, the same statewide overview notes that “several other companies, including Apex Clean Energy of Virginia, are acquiring lease rights and working on plans.” (Wait, what? Yup, the same outfit that just told us the setbacks ruined everything so they’d be taking their toys and going home still have four Ohio projects in the pipeline.)

It’s disheartening to see the wind industry employing these same shopworn scare tactics about moderate setbacks; no matter what the proposal, if it’s an increase over something that has been on the table, it’s decried as “killing” the possibility of wind energy in the area.  Anything over the 750-1000 foot setbacks that the industry prefers is considered extreme; in Ohio, claims that the old 1300-ft to homes setback was among the most stringent in the nation are practically a joke, with 1250-1500-foot limits now becoming the norm, and many areas going much further.  In Minnesota, a 1500-ft setback was eagerly embraced in lieu of a proposed 2700-ft rule; in Maine, a 2000-ft setback was deemed perfectly workable by a developer who was fighting a change to 4000-ft, after which they switched gears and pinpointed a 35dBA noise limit as the real “deal killer.”

Indeed, nighttime noise limits of 35dB or less can mean that setbacks will need to be large enough (4000 feet or more) to rule out development in most communities.  Still, it’s entirely reasonable for some towns to choose such low noise limits, or setbacks of a half mile or more, if the priority is to preseve the rural character of place and assure that few if any residents will hear turbine noise on a regular basis.  Ideally, these more restrictive rules would also include the option that wind developers can obtain noise easements from neighbors who are willing to live closer to turbines (often in return for a financial payout, either one-time or annual).  And guess what?  The much-decried Ohio rules do allow individual landowners to waive the setback requirement, if they wish to; this may be part of why so many projects are still happening.  It’s time for the wind industry to stop moaning about setbacks meant to preserve some semblance of rural character, and begin making peace with the fact that not all communities will make the same choices about opportunities for economic development.

Looking ahead in Ohio: Even as Amazon, Apex, and others proceed with their plans in Ohio, representatives from several northwestern Ohio districts have introduced a bill to let counties supersede the state rules and revert to the old setback standards on a case by case basis. (Will it surprise you to hear that it’s in this very region where Amazon is happy to build with the current rules? I thought not….)  So far, there does not seem to be any active reconsideration of the other key element of the 2014 rule changes in Ohio, a 2-year freeze of the state renewable energy portfolio standard (RPS) at 2.5%—foregoing the planned 1% annual increases toward a 2025 goal of 12.5%—while the legislature reviews the RPS program. Presumably, a decision will be made during the coming year whether to revert to the old schedule or adopt new, lower targets.

UPDATE, 1/29/2016:  While I’m not tracking all the news related to new projects, a couple of things caught my eye recently.  Two companies, including Apex, abandoned plans for wind farms in Ohio, though the news reports, and perhaps the formal notices filed with state regulators, don’t specify why; there are many reasons that proposed project aren’t completed, including the financial health of the companies themselves, and the fact that they often do preliminary work in many more places than they ultimately choose to build.  Relatedly, the Scioto Ridge Wind Farm, which was among those supposedly threatened by the new Ohio rules, is still under development; on January 26, the project’s Facebook page recently posted a local news article about an agreement reached between Everpower and a local opposition group, which reduced the number of turbines from 176 to 107; such reductions sometimes involve a move to bigger turbines, and it’s unclear whether the footprint is smaller (and so some setbacks larger) under the agreement.  Nonetheless, another local group has vowed to continue fighting the plans.

Ocean listening stations sprouting around US

Bioacoustics, Default, Ocean, shipping No Comments »

NOAA NRS_Stations_plus Cordell BankA new network of long-term acoustic monitoring stations is being deployed by NOAA-funded researchers in ocean waters from Massachusetts to the Arctic and Samoa. The Ocean Noise Reference Station (ONRS) Network represents the next step in data collection for NOAA, which has increased its focus on ocean noise in recent years.

Agencies, researchers, and NGOs are all concerned about the effects of chronic moderate noise on whales, seals, and fish (along with crustaceans and even eggs and larvae).  NOAA’s ocean noise mapping project is a big step forward, but it’s largely based on modeling of known ship and seismic survey activity.  Actual recordings made at sea by various researchers serve as “ground-truthing” for these models; early indications have been that the models are pretty good, usually within 5-10dB of actual recorded levels.

The ONRS network takes acoustic monitoring another step forward by deploying identical equipment in many regions, thus collecting “consistent and comparable multi-year acoustic data sets covering all major regions of the U.S.”  In addition to getting a better idea of regional differences (and consistencies), researchers will be investigating “how the ‘soundscapes’ at each of these sites changes, i.e. does it become noisier, are there more or less biological sounds, and is there a dramatic shift in the species present?”  All this will feed into NOAA’s ten-year effort to develop an Ocean Noise Strategy.

cordellThe most recent deployment took place this fall at the Cordell Bank National Marine Sanctuary off the coast near San Francisco (it’s not even on the maps on the NOAA site yet, though I added it above as NRS11).  The hydrophone deployment mission (right) received substantial funding from the International Fund for Animal Welfare (IFAW), along with the ongoing NOAA support for data collection and analysis.  Cordell Bank is one of the richest foraging grounds for marine mammals, thanks to an upwelling of cold water that attracts a wide range of species to feed.  At the same time, many of the thousands of ships traveling from Asia to ports in San Francisco Bay and further south along the California coast pass close enough that their “acoustic footprint” extends into the Sanctuary.  This can, at the very least, make it harder for whales or fish to hear each other as well as they’re used to, limiting the area over which they can communicate and causing them to raise their voices.  There are also indication that some species expend energy avoiding moderate noise, and that feeding and perhaps mating can be temporarily disrupted.  Most pernicious may be the possibility that living in elevated noise can increase physiological stress, triggering “a suite of negative effects,” according to one of the researchers.

Other research efforts are also adding to our understanding of the effects of shipping noise.  In Canada, Port Metro Vancouver recently deployed a hydrophone to examine the underwater noise from container ships headed into its facilities.  3000 such vessels traverse the waters each year, along with even more ferry transits and various recreational boats.  It’s part of the Port’s Enhancing Cetacean Habitat and Observation Program. One of its most interesting goals is to zero in on ships that may be unusually loud and in need of some maintenance:

The hope is to establish baseline information to track noise levels and to identify noise levels from specific ships. The results could lead to simple mitigation measures such as hull and propeller cleaning, shore-based financial incentives, and information for regulatory agencies and for naval architects to build quieter ships.

Here’s some more from the researchers on that project.

And in the Bering Sea, acoustic monitoring is providing important baseline data on marine mammal presence, which will play into any future oil and gas development, as well as the potential for global shipping to extend into Arctic regions as polar ice melts:

“This passive acoustic monitoring technique allows us to detect the presence of vocalizing marine mammals continuously — 24 hours per day — in all weather conditions, over periods of weeks to months, over distances of 20 to 30 kilometers, and is a proven sampling method in the waters offshore Alaska,” explained lead researcher Kathleen Stafford.

Meanwhile, eavesdropping went on during the summer and fall in the Gulf of Mexico, and plans are being made for a recording network all the way around Antarctica, in some of the world’s most remote and acoustically pristine waters.

We’re listening more closely and widely than we ever have—the next question will be, are we willing to actually do something with what we learn, and find ways to slow or roll back our relentless intrusion into the natural soundscapes of the oceans?

VT study sheds light on how often wind farm noise reaches bothersome levels

Wind turbines 2 Comments »

VT SheffieldA sneakily fascinating legal response was recently released, in which the State of Vermont Department of Public Service (DPS) responds to request by wind farm neighbor Paul Brouha for relief from noise coming from the Sheffield Wind Farm.  Most of the technical back-and-forth amounts to quibbling between sound experts about 1-3dB differences, caused by slightly different monitoring techniques.  This minutia matters, in that it may determine whether the Sheffield project is just barely in compliance or just barely too loud at times; after all, limits are limits.  However, as usual in such situations, even if slight adjustments in operations were made to bring the sound levels down 1-3dB, such small changes are unlikely to change how loud the sounds seems at the home in question (the human ear generally can’t perceive a difference of less than 3dB).

Still, buried in the data at the end of the submission is some interesting information about how often sound levels reach various thresholds in each season.  The wind farm company, Vermont Wind, had done some on-the-ground sound monitoring at a location slightly closer than Brouha’s home, and the results shed some light on why some wind farm neighbors may be bothered by the noise.

Click through for the full story. Read the rest of this entry »

New paper pinpoints “opportunity sites” for acoustic habitat protection near proposed oil sands shipping route

Bioacoustics, Ocean, Science, shipping No Comments »

AEI lay summary of Rob Williams, Christine Erbe, Erin Ashe, Christopher Clark. Quiet(er) marine protected areas. Marine Pollution Bulletin (2015), j.marpolbul.2015.09.012  View or download paper online

Over the past decade or so, concern about ocean noise has expanded from its initial focus injuries and deaths caused by periodic loud events, such as sonar or seismic surveys.  Many researchers are now working to understand the ways that widespread, chronic shipping noise affects marine creatures’ behavior, foraging success, and stress levels.  Long-term deployment of hydrophones, sound models that extrapolate from shipping data, and slow-but-steady improvements in our knowledge of the hearing ranges and population densities of particular species have all combined to open exciting new avenues for research that can inform policy decisions in the years to come.

Using these new measurement and modeling techniques, researchers can quantify the “acoustic quality” of marine habitats.  This starts with charting the extent of shipping noise, while also considering the different auditory ranges of various species of interest.  Next, researchers map where animals tends to congregate in various seasons, to identify areas that are especially important to each species.

Of particular importance is identifying areas that have, so far, remained relatively free of shipping noise.  If at all possible, we’ll want to avoid extending the human noise footprint into these increasingly rare acoustic havens.  A research team that’s been active on Canada’s southwest coast over the past few years has been at the forefront of these techniques, and has just published a new paper that introduces the concept of “opportunity sites”—areas used by each species that are still relatively quiet, and so have high long-term conservation value.

“We tend to focus on problems in conservation biology. This was a fun study to work on, because we looked for opportunities to protect species by working with existing patterns in noise and animal distribution, and found that British Colombia offers many important habitat for whales that are still quiet,” said Dr. Rob Williams, lead author of the study. “If we think of quiet, wild oceans as a natural resource, we are lucky that Canada is blessed with globally rare pockets of acoustic wilderness. It makes sense to talk about protecting acoustic sanctuaries before we lose them.”

Below left: population density of harbor porpoise in coastal waters of British Columbia; below center: ship noise, weighted to harbor porpoise hearing; below right: opportunity sites to preserve high-quality acoustic habitat for harbor porpoises. Red indicates “highest”, blue “lowest” on all maps.


These new opportunity maps make it painfully obvious how little of each species’ habitat is free of excessive shipping noise. In the example above, harbor porpoises can only find high quality acoustic habitat in a couple of small areas.  Without some concerted effort to protect these areas, they will continue to shrink.

While recognizing that many areas of critical habitat are already too loud (in particular, the entire Seattle/Vancouver region), the authors acknowledge that reducing existing noise is difficult—limiting shipping, or reducing the noise made by boats, has social and economic costs that can be hard to accept.  By contrast, the areas they’ve identified merely need to be maintained in close to their current acoustic condition, which will be far easier to accomplish.  As the authors note:

In our professional opinion, if two places are equally important to whales, with one being noisy and the other being quiet, it would be helpful to identify those areas and present that information to decision-makers. The noisy area may require mitigation, whereas the quiet area may make a more attractive or convenient candidate for critical habitat protection, either because it represents higher quality habitat to the animals or because it imposes lower economic costs to society to mitigate anthropogenic threats.

This may not mean excluding new activities from these regions, because, again in the authors’ words, “a particular marine environment could be dominated by anthropogenic underwater noise that is perceived as being loud to one species, but quiet to another.” Indeed, the opportunity maps differ for each species (though that area on the eastern side of the large island of Haida Gwaii recurs in most).  So, we will need to pay close attention to what species are present, how well they’ll hear the new noise sources, and the ways they may respond.

Generally, large ship noise is far more audible for baleen whales (humpback, fin, etc.) than for smaller toothed whales (dolphins, orca), which vocalize and hear at higher frequencies. That’s not to say that the smaller whales don’t hear big ships; they often do, and in many cases, they respond at a lower sound level than larger whales, so even if the ships are “fainter” to their ears, their reactions may be similar.

humpback opportunityWhile this paper steers clear of any sort of advocacy tone, and does no more than present the new “opportunity sites” analysis and mapping technique, the waters being studied are at the center of a contentious public policy debate.  The proposed Northern Gateway pipeline from the oil sands region of Alberta would dramatically increase tanker traffic to the existing deep-water port at Kitimat (yellow arrow, left).  Such an increase through Caamano Sound (red arrow, left) would threaten the humpback whale opportunity site (map, left) identified just south of the Sound.  Several years ago, co-author Rob Williams told reporters, “Caamano Sound may be one of the last chances we have on this coastline to protect an acoustically quiet sanctuary for whales. … We don’t exactly know why this area is so rich, but there are some long, narrow channels that serve as bottlenecks for food, making it easier for whales to feed.” A consortium of environmental organizations is currently challenging the Canadian government’s approval of the pipeline, claiming that the approval did not take into account the humpback recovery plan, identifying Hecate Strait (the larger area between the mainland and the large offshore island) as a critical humpback feeding ground.  The pipeline is being challenged on several fronts (including strong opposition from B.C. First Nations communities); considering acoustic habitat protection, limiting new ship traffic during the times of year when the current opportunity sites are being heavily used would seem to be the least we can do.