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Denali Flight-seeing Guidelines End First Season

Human impacts, News, Vehicles Comments Off on Denali Flight-seeing Guidelines End First Season

In April, a set of voluntary guidelines for air tours in Denali National Park was released, meant to minimize noise intrusions on backcountry hikers.  An Aircraft Overflights Advisory Council spent a bit over a year coming up with the proposals, which included asking pilots heading for the summit of Mt. McKinley/Denali to avoid two high-altitude camps used by people climbing the mountain.

A  "sound station" on the Ruth Glacier is monitoring the noise level of aircraft landing on the glacier. NPS Photo.

A “sound station” on the Ruth Glacier is monitoring the noise level of aircraft landing on the glacier. NPS Photo.

Likewise, Kahiltna Glacier campers have been subject to planes climbing to cross Kahiltna Pass, where pilots are encouraged to climb to altitude before approaching the pass.  According to the Denali website, these “best practices” are designed to safely reduce sound impacts in key areas, and are subject to refinement and revision as operational experience is gained.  The Park Service is monitoring the effectiveness of the measures; Charlie Sassara, who is a member of the Council, says that “we will now try to look at additional mitigation measures to enact in 2010.”

Acoustic Deterrent Weapon Used in Pittsburgh

Human impacts, News Comments Off on Acoustic Deterrent Weapon Used in Pittsburgh

The Pittsburgh Police used a new acoustic deterrent device as part of its actions against protesters during last week’s G-20 meeting.  The  Long Range Acoustic Device (LRAD), which emits a high-frequency sound similar to a smoke detector, is designed to disperse crowds using sound at or near the human pain threshold. Termed a “non-lethal weapon,” it was originally intended for use by ships trying to deter attack, and has also reportedly been used against crowds in various Middle Eastern conflicts in recent years.  With a source Sound Pressure Level of 146dB, its sound is above the threshold for pain (130dB) out to about 20 feet; at 50 feet (120 dB), it can cause some permanent hearing damage in 30 seconds.  At distances out to about 100 yards, it is louder than 106dB, which  can cause hearing damage in about 4 minutes. The video that follows after the break focuses more on the truck than on the responses of the crowd; some people have their fingers in their ears, but no one seems incapacitated at all, indicating that sound levels were loud but likely not generally painful. Read the rest of this entry »

UK Study: Some Birds Avoid Wind Farms

Effects of Noise on Wildlife, News Comments Off on UK Study: Some Birds Avoid Wind Farms

A study commissioned by the Royal Society for the Protection of Birds (RSPB) found that many species of birds avoid nesting in areas within 500 meters of wind turbines.  The RSPB, like its US conterpart the Audubon Society, has been largely supportive of wind energy.  The new study was the most detailed yet of bird distribution around wind farms: twelve major upland wind farms were surveyed six times during the breeding season for a dozen common species including waders and gamebirds (golden plover, lapwing, curlew, snipe, red grouse), raptors (buzzard, hen harrier, kestrel), and songbirds (skylark, meadow pipit, stonechat and wheatear).  Of the 12 species studied, 5 seemed undisturbed, while populations of 7 were 15-53% lower when within 500m of a wind turbine.  The displacement effects continued out to a distance of about 800m (roughly a half mile).  The affected species were buzzard, hen harrier, golden plover, snipe, curlew, wheatear and meadow pipit.

Image from The Telegraph; click to read article

Image from The Telegraph; click to read article

It is crucial to note that this study was looking at nesting patterns, and does not suggest that birds are being killed by the turbines, but rather that they avoid nesting near them, presumably because of increased noise, which could disrupt communication between birds or reduce the amount of prey and make it more difficult to hunt (whether for insects or rodents).

UPDATE: I recently came across a paper from last year that found no obvious avoidance of wind farms by most wintering species of UK farmland birds.  This paper looked not at nesting patterns during breeding season, like the paper above, but rather at wintering birds’ presence (they walked randomized paths, and counted birds seen; most were seen when flushed from the grain).  Looking at numbers seen in 5 sets of distances (from 0-150, to 600-750m), wintering farmland birds (seed-eaters, corvids, gamebirds and Eurasian skylarks) showed no increase with increasing distance. A further investigation of 0-75m and 75-150m also showed no trend.  Only pheasants showed a tendency to be found in the segments further from turbines.

Blue Whale Call Rates Rise Dramatically Near Seismic Survey

Science, Seismic Surveys 5 Comments »

A new study published in Biological Letters found that a seismic survey in wide bay at the mouth of the St. Lawrence Seaway caused blue whales feeding and socializing nearby to double or triple their call rates.  The calls were near-range communication signals, rather than the long, loud songs that are heard over hundreds of miles. The research was meant to simply learn more about these social calls, but during the study, their recordings began to pick up the pulses from a seismic survey.  “The whales made more calls on days when the testing was happening. It seems they are having to repeat themselves in order to not lose information,” said lead researcher Lucia Di Lorio.  They also called more on survey days when the sounds were not audible than when they were, and tended to rapidly increase calls when the sounds appeared.

Blue whale at surface.    Image: Wikipedia Commons

Blue whale at surface. Image: Wikipedia Commons

Blue whales, the world’s largest animal, number just 5-10,000, are solitary for most of the year, making these summer-time feeding gatherings especially important; di Lorio notes that “We don’t yet know a lot about what these calls mean…They come to eat, but also to check out each other, maybe find a mate.”

The results were especially surprising, since the survey in question was using a much lower-power source than many surveys, and at levels much lower than those typically considered likely to cause problems.  “It’s used [here] because it’s thought to have a lower impact on marine life,” di Lorio told the BBC, “But we should definitely reconsider these things, because clearly it’s not only the sound level that’s important; and one thing might be not to do the test when there are lots of whales around.”

Read the rest of this entry »

Scientists Urge Pause in Alaskan Offshore Oil/Gas Expansion

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As the extended public comment period expired for input into the Obama administration’s approach to offshore oil and gas exploration, public pressure mounted to take a time-out on plans for expanded development in Alaska’s offshore waters.  During the Bush administration, the Minerals Management Service began planning for offering new leases in the Beaufort Sea (north of Alaska),  Chuckchi Sea (northwest of Alaska, north of the Bering Strait) and in Bristol Bay (north of the Aleutian peninsula).  Native groups and environmentalists have expressed concern about noise impacts on sea life during exploration, and risks to the fragile ecosystem should full-scale development proceed.   Signatures from 300,000 people supporting a halt in new leasing and drilling were delivered to the Department of Interior in DC, and a letter signed by 400 scientists urged the administration to “take a time out from offshore industrial activity to allow for a precautionary, science-based approach that better assesses the consequences of development in a rapidly changing ecosystem.”  One of the key arguments made in recent years has been that the Arctic environment is changing rapidly in response to global warming, and that further stressing habitats with oil and gas development is ill-advised.  “We still have a chance to do it right in the Arctic. All we’re really asking is that for once we look before we leap,” said Jeffrey Short, Pacific science director for Oceana and former National Oceanic Atmospheric Administration research chemist. That means taking a precautionary, science-based approach to oil and gas development, including assessing environmental impacts before issuing permits, sustained monitoring and comprehensive planning to determine the best way to proceed, the scientists say.

Obama family visit grounds Grand Canyon air tours, as NPS forges ahead with new plan in wake of consensus group failure to agree

Human impacts, News, Vehicles, Wildlands 1 Comment »

After eight years of struggling to bring conflicting interest groups together to support a consensus alternative for managing air tours at Grand Canyon National Park, an FAA-organized Grand Canyon Working Group has adjourned indefinitely.  The Working Group included NPS, FAA, tribal, environmental, and aviation industry representatives. At the Working Group’s last meeting, in late June, the GCWG disagreed on NPS alternatives, including a seasonal shift in air-tour corridors by alternatively closing the Zuni and Dragon corridors, which are now open concurrently.  According to a recent article in Aviation International News,  “The FAA does not have a role at this point,” said Lucy Moore, the GCWG mediation facilitator, adding “When the NPS presents one preferred alternative, the FAA will then review it for safety issues.”  In recent years, the NPS has clarified its goals to meet congressional mandates to “substantially restore” natural quiet in the canyon; they are aiming to have half the canyon be free of air tour noise 75% of the time, though high-altitude jet flight will not be regulated.  The Park Service is aiming to release a draft EIS in 2010; see their overflights web page for more details.  At the June Working Group meeting, participants noted that the Park Service seemed more engaged and prepared to push for protecting natural quiet than during the previous administration; however, it is unlikely that the NPS plan will have as dramatic an effect on reducing air tour noise in the canyon as did an August visit by the First Family, when dozens of air tours were grounded for much of the day during a peak visitation period.

Lynda Barry Leads Wisconsin Wind Farm Resistance; Pens Cartoon Featuring Suffering Neighbors

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Well-known cartoonist Lynda Barry lives in rural Wisconsin, and while her home is not in the midst of a wind farm, she has become a leader of local resistance, with a focus on the noise that keeps people awake, and strange physcial sensations, including one that she herself experiences when near operating turbines. “You know how sometimes, around your eye, you’ll get this little tic that kind of wiggles?” says Barry. “It was like having that in your ear and your chest. A pulsing. It’s the weirdest feeling!”  She experienced this while visiting a home 1100 feet from the nearest turbine, one of many homes she’s visited and spent the night in as she has worked to understand what some wind farm neighbors are living with.  Her work is highlighted in a recent feature article in Isthmus, a Madison weekly, which is illustrated with a classic-style Barry cartoon in which each panel highlights a different neighbor’s story.

Maine Medical Assoc Calls for State to Modify Permitting Process for Wind Farms

Health, News, Wind turbines 4 Comments »

Following up on concerns expressed by locals near the Mars Hill wind farm, and preliminary studies done by a local doctor, the Maine Medical Association overwhelmingly approved a formal resolution that stresses “a need for modification of the State’s regulatory process for siting wind energy developments,” in order to reduce controversy and incorporate the latest evidence-based research results. The statement urges the Department of Environmental Protection and Land Use Regulation Commission to refine their procedures to reflect potential health effects, and to concertedly explore these effects, and calls on the MMA and doctors to work with regulatory agencies to provide what scientific information is available (scroll down at link above to read the final resolution wording). Two weeks earlier, the MMA’s Public Health Committee had rejected the proposed resolution, which many members felt was worded more strongly than current evidence would support; the resolution was slightly re-worked, and met with approval at the MMA’s annual session.  One of the resolution’s sponsors, Dr. Michael Nissenbaum, MD, is in the midst of completing a study of the residents both near the Mars Hill wind farm, and those further away, in an attempt to assess any significant differences.  The first part of his study (centered on interviews with wind farm neighbors) is available now, with the second part (similar interviews with residents out of earshot) still underway. A two-part radio interview with Nissembaum is available here.  A two-part local news feature on the Mars Hill controversy is available here.

Puget Sound Boat Noise May Make Orcas Use More Energy While Foraging

Animal Communication, Effects of Noise on Wildlife, Ocean, Shipping 2 Comments »

Ongoing research by NOAA’s Northwest Fisheries Science Center continues to look more deeply into the effects of boat noise on Puget Sound orcas.  The research team, led by Marla Holt, had previously found that orca calls increase in volume in step with background boat noise: for each decibel of added background noise, their calls also got a decibel louder.  In their latest round of research, the team is trying to determine whether the background noise is diminishing their foraging success due to masking (drowning out) some of the critical group communication, and whether calling louder makes the animals use more energy.

Image courtesy National Geographic

Image courtesy National Geographic

A 20% population decline among the Southern Resident orcas during the late 1990’s has been attributed to a combination of fewer salmon, toxins, and vessel noise. According to a recent article on National, Holt, who will present the team’s preliminary findings in October at the Biennial Conference on the Biology of Marine Mammal in Quebec, said that their research indicates killer whale communication is particularly important during hunting. What’s more, previous studies in birds had suggested that the animals consume more oxygen to raise their voices above ambient noise, making their metabolic rates spike and burning up stored energy, Holt said, adding that it’s possible the same phenomenon could be occurring with killer whales, although it’s too early to know for sure.

NOAA’s recovery efforts for the orcas include new regulations that will keep whale-watching vessels 200 yards from orcas, as well as efforts to reduce toxin pollution and to restore salmon runs.  Longtime orca researcher Ken Balcomb feels it all comes down to the decline in salmon: “If you deny them the food, [there’s] basically no point in worrying about other factors,” Balcomb said. He calls the whale-watching limits “feel-good thing,” adding that “my observations over 35 years [are] that [whales] don’t really get disturbed by anything, much less vessels.”  Holt acknowledges the limits of the new regs, saying that “a lot of people would argue, Why focus on these vessel regulations? But it’s one thing we can do immediately.”  It appears to AEI that the question is not really whether the boat noise disturbs the orcas, but whether it may drown out parts of their foraging communication, making it more difficult for them to find and eat the few salmon that do remain available to them.  And, given their tenuous situation, if they are forced to use more energy to call during hunting, their overall health is likely to be at least somewhat affected.  Moreso, each time that a particular foraging attempt is aborted due to a noise intrusion, a larger bit of the daily energy budget has gone to waste.  Time will tell whether the new boat limits actually lower the received sound levels for foraging whales; if so, it’s a step in the right direction.

Nature Conservancy Creating Maps to Guide Prairie Wind Farm Siting

Effects of Noise on Wildlife, Human impacts, Science, Wind turbines 1 Comment »

A feature article in the fall issue of The Nature Conservancy’s magazine takes a close look at the rapid expansion of the wind industry in America’s prairie heartland.  The rolling hills of Kansas are a prime wind energy corridor, and TNC is concerned that the remnants of tallgrass prairie habitats could be irrevocably harmed if new wind farm development is not done carefully.  Rob Manes, TNC’s Director of Conservation for Kansas, sits on the Fish and Wildlife Service advisory committee that is developing wind farm siting guidelines, where he has proposed that key habitat be identified in advance, so that wind companies can plan around it.  Such landscape-scale analysis is already being done by some wind companies, and Manes urged the committee to recommend that the practice become standard procedure.  Manes imagines an ever-expanding regional database that would not only would provide maps of important environmental data, such as critical habitat for endangered species, but also would designate wind-friendly areas where turbines and wildlife are less likely to be in conflict.  (This idea is closely related to Marine Spatial Planning, as addressed in this recent AEInews post.)

From the TNC article: Manes is certain that a national set of detailed maps overlapping wind and wildlife resources is crucial to “doing wind power right.” That is because the Conservancy and its partners have already implemented a system of maps in Kansas. And local developers have responded enthusiastically. Horizon Wind Energy even worked with the Conservancy and the Ranchland Trust of Kansas to set aside protected lands to offset the footprint of one of its wind-farm developments.  “Our contacts in the wind industry said, Show us where we can develop our projects — so we did,” Manes says. The map shows the state’s native prairies, prairie chicken habitat, wildlife refuges and nature preserves, as well as where the best wind resources are. Now, when a wind developer wants to build in Kansas, the company knows which sites are likely to raise the ire of conservationists — and which areas aren’t.

The Conservancy has created similar maps in a handful of other states, including Colorado, Montana and Oklahoma. And in mid-2009, the Conservancy was awarded a contract to create a wind and wildlife resource map for the entire country. The map initiative is funded by the American Wind and Wildlife Institute, a coalition of wind-industry and conservation organizations with the aim of reducing conflicts between wind development and wildlife.

UPDATE: In the UK, the Royal Society for the Preservation of Birds, along with Scottish Natural Heritage, has initiated a similar project, centered on the production of a Bird Sensitivity Map for use in planning wind farms in Scotland. See this link for more information on the program, and click here to download the BSPB Bird Sensitivity Map Report.  Scottish Heritage previously released “Strategic Locational Guidance” for onshore wind farms.

Ontario Wind Projects Lack Independent Environmental Analysis

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While the province of Ontario appears to be onto something promising with its new Green Energy Act (see recent AEInews post), local wind skeptics point out that in recent years, the province has taken wind developers’ environmental assessments at face value.  Citizens can request that the province conduct a full-scale independent assessment, and indeed, such requests have been put forward 31 times since 2006.  In every instance to date, however, the request has been denied (nine are currently outstanding).  Provincial authorities assure that the required private assessments include taking into account citizen concerns, and often involve mitigation, as part of “a lot of back and forth” between the companies and provincial regulators.  Regarding noise issues (AEI’s primary concern), it would seem prudent to do some “ground-truthing” of industry sound propagation models: if there are instances in which neighbors are being affected by unexpectedly high noise levels, then future assessments should be sure to not use the same models that failed earlier.  This is but one example of the value that even a few independent assessments could offer as the province moves forward with its ambitious plans to abandon coal-generated power.

Animals Finally Respond to Music: It Just Has to be Written for Their Species!

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Fascinating discovery of the day: music written for monkeys, based on their vocalizations, finally triggers a notable response.  What follows is straight from the website of the composer, who also makes music for cats.  You can hear an NPR story on the monkey research here.

Many previous experiments on animal response to music composed for humans (hereinafter, “human music”) have been conducted, but none of these studies had demonstrated significant responses. Very recently a study of the effect of human music on cotton-topped tamarin monkeys was conducted at Harvard. The tamarins showed a slight preference for Mozart over German “techno” music, but preferred silence to either. This study was consistent with the findings of all previous studies: animals are largely indifferent to human music.

We performed tests at the University of Wisconsin on the same species of tamarins. As with all previous studies, the tamarins showed a lack of interest in the human music. By contrast, the effect on them of the species-specific music composed by David Teie was remarkably clear and convincing. They displayed a marked increase of activity in response to the music that was designed to excite them, while the “tamarin ballad” music induced a significant calming. This calming effect was measured against the baseline of silence; they moved and vocalized less and orientated more toward the audio speakers during and immediately following the playing of the tamarin ballad.

Following are quotes from a research paper about these experiments that will soon be submitted for publication. The psychologist Charles Snowdon, who conducted the testing and authored these statements, is a highly respected but extremely cautious and skeptical scientist not normally given to making sweeping statements: “Our predictions were supported. Music composed for tamarins had a much greater effect on the behavior of tamarins than music composed for humans. …tamarins displayed significant behavioral change only to the music that was specifically composed for them and were unaffected by human music.”

To the best of our knowledge, this marks the first time that an art form has been shown by scientific test and observation to engender the measurable appreciation of any species other than human. (Ed. note: true, little science has been done; yet there have been some compelling examples of animals themselves enjoying doing art: the painting gorillas and Thai Elephant Orchestra come quickly to mind.)

Ontario Wind Push Triggers Residents AND Industry

Health, News, Wind turbines 1 Comment »

A great short piece in Canada’s esteemed Maclean’s magazine from early August highlights the aggressive push being made by provincial minister of energy to open up the province for wind power.  George Smitherman, the self-styled “Mr. Wind,” may be on to something, because his initiatives are stirring up both anti-wind activists concerned about noise and health effects AND the industry itself, aghast at new setback requirements for large wind farms.

A combination of requiring utilities to enter into long-term, premium price contracts with wind farms and a massive upgrade to the distribution grid has spurred plans for 103 new “shovel-ready” windfarms in the Province, especially along its extensive Great Lakes shorelines.  This has locals worried, after hearing tales of woe from wind farm neighbors elsewhere.  Dr. Robert McMurtry, a former dean of medicine at the University of Western Ontario, says that  “When I first read about the side effects I thought that they didn’t sound very convincing. But then I did my homework, and I became alarmed.”  Based on surveys he has done, and others in Europe, McMurtry estimates that 25 per cent of people living within 2.5 km of turbines experience disruptions in their daily lives, especially sleep disturbances, which often balloon into other health problems. He thinks that there are enough problems, in wind farms worldwide, to justify a serious epidemiological look at the industry. “You can assume that all these people are liars,” says McMurtry. “But many of these folks will tell you that they welcome wind turbines. They just want someone to turn them off at night, or move them further back.”

New provincial set-back standards issued in June may well be just what this doctor ordered. While not going all the way to 2.5km (about 1.5mi), the new standards call for increasingly large setbacks for larger windfarms, peaking at 1.5km (just under a mile) for wind farms of over 26 turbines; smaller wind farms can be 550m away, loud small ones 950m away.  The Canadian Wind Energy Association claims that these new rules will require changes in 96 of the projects, with 48% of their turbines out of compliance; 79 of the projects are now either “non-viable” or require “back to the drawing board” redesign.

Smitherman is not phased by either side’s reactions.  “I totally understand that there aren’t many people out there looking for more electricity infrastructure in their backyards,” he says. And if somebody has to go back to the drawing board and redesign some projects, “I apologize that it will be inconvenient in some circumstances. But bigger setbacks are part of the Green Act.” But he’s unapologetic about the larger goal, one that would be truly revolutionary: to eliminate coal-fired electricity by 2014—only five years away.