After a bit of a lull, I’ve spent much of the past couple days catching up on the folder full of research published in recent months, and summarizing key papers on the main Acoustic Ecology site.  Among the studies worthy of attention are:

• The first direct test of harbor porpoise sensitivity to seismic survey airguns confirms many observations from the field that this species is especially sensitive to noise; both temporary hearing loss and avoidance of sound occur at relatively low noise levels
• Orcas and dolphins seen to reduce foraging in the presence of boat noise
• Wind turbines don’t seem to replace most small wintering farm birds, but oil development noise can reduce forest bird abundance
• Right whales summer habitat is loud most of the time, suggesting a pressing need to identify their breeding grounds and assure they can hear each other there
• Two great overviews of fish hearing

See these and more at the AEI lay summaries of new research page.

Nice find of the day: A page on the Yosemite website describing the work they did over the past two summers to assess the soundscapes in the park.

http://www.nps.gov/yose/naturescience/soundscape.htm

And that’s not all!  There’s also a link to a half-hour MP3 file/podcast featuring the NPS Natural Sounds Program’s lead scientist, Kurt Fristrup, talking about his studies of the effect of noise on predator-prey relationships (a line of research that I tell people about more often than nearly any other), as well as noise effects on animal communications and human physiology. The audio feature also addresses the acoustic health of Yosemite as well as some interesting discoveries made possible through recordings made in the wilderness.  See the webpage here, and listen to the MP3 story here.

The revised draft of wind energy wildlife impact guidelines released by a US Fish and Wildlife Service Federal Advisory Committee was released in March, and like the first version, contains not a single occurrence of the words “noise” or “acoustic.” The Committee is directed to “recommend effective measures to avoid or minimize impacts to wildlife and their habitats related to land-based wind energy facilities.” How they can provide provide this guidance without considering acoustic impacts is simply unimaginable.  Modern wind turbines are hundreds of feet tall, and create significant sound; even the minimal setbacks for human residences are 1000 feet, with many cases of bothersome noise (especially at night) at a half mile or more.  Wildlife impacts of wind farms are sure to include increased ambient background noise over a fairly large area (half mile to a mile in diameter), which can make it more difficult for predators such as owls and coyotes to find their small prey, and likewise force prey animals to be more vigilant against attack, which has clear energy costs for the animals.  In addition, low-frequency noise radiated into the ground could affect burrowing animals.  Especially in “islands” of woods along ridgelines surrounded by farm land, this acoustic degradation could displace animals from key habitat; even in larger woodlands, steep terrain along ridgelines often contains a different mix of trees and thus habitat that is locally important.  As AEI noted in comments submitted to committee members in February, “In at least some situations/locations, acoustic impacts could be a primary or substantial contributing factor in displacement from habitat, as well as triggering stress that may have synergistic relationships with other impacts.”  Such considerations are basic requirements for effective analysis of impacts on wildlife.  The Committee briefly considered noise impacts, but concluded that no data (specifically involving turbine noise) was available with which to assess the possible effects.  As with ocean noise, though, this lack of specific data does not preclude assessing possible or likely impacts, using studies of other noise sources or even other species than those present at a given project area; NOAA and the Navy routinely take this approach to assessing the impacts of various ocean noise sources.  There is plenty of research on the noise impacts of oil and gas installations, road noise, and aircraft noise on many families of wildlife (birds, rodents, large mammals, etc.).  The National Park Service Natural Sounds office and bioacoustics researchers at universities across the country are good sources of information that this Federal Advisory Committee surely needs to consult before moving forward with guidelines for assessing the impacts of wind farms on wildlife.  These guidelines will shape wildlife impact analyses for years to come, and need to be done right.  

For more on the FWS wind advisory committee, see:
http://www.windaction.org/articles/21154
Industrial Wind Action Group letter to Sec. of Interior Salazar, May 2009

http://www.fws.gov/habitatconservation/windpower/wind_turbine_advisory_committee.html
Advisory Committee website 

The University of Utah’s free digital archive of recordings from wild habitats in the American West has grown to over a thousand items. “Our premise is that the sounds of the west are unique and that they deserve a closer listen,” says research librarian Jeff Rice. “As our lives become more urbanized, we are losing our connection to the natural world and its rich sounds. There are whole generations of kids growing up that have never heard coyotes, or even frogs, in the wild. This is our heritage and we want to help restore some of that connection.” By focusing on the sounds of the western U.S., the archive emphasizes the connection between sound and place—something that is not only culturally valuable, but also biologically crucial, say scientists. Scientists recognize that even the same species of animals can sound different based on their geography. Birds, especially, can sing in dialects unique to their areas“Frequent recordings in many areas help create a database that will give insight into how the ‘singing culture’ of birds changes over time and space,” says Dr. Franz Goller, a biologist at the University of Utah. “Efforts like the Western Soundscape Archive are therefore very important in documenting acoustic behavior.” Source: Innovations Report, 3/18/09 [READ ARTICLE]
Western Soundscape Project Website: [MAIN SITE] [VIDEO INTRODUCTION]

The early 2009 issue of Conservation magazine, the popular press publication of the Society for Conservation Biology, has a great overview piece on the effects of noise on animals. It focuses on changes in animal behavior and song that have been observed over the course of the past decade, drawing on studies from several different researchers. Much will be familiar to AEI regulars, but it remains highly recommended for sharing with others and for the concise overview it provides.

See the article at http://www.conservationmagazine.org/articles/v8n2/not-so-silent-spring/

A three-year research project in Scotland has been announced, which will study the impacts of tidal energy turbines on sea life. From Wave and Tidal Energy News:

The groundbreaking study will be conducted through a PhD studentship at the Scottish Association for Marine Science (SAMS UHI). It will look specifically at the background noise levels in areas being considered for tidal renewables development, as well as the noise made by tidal turbines. It will also explore the extent to which marine animals, particularly protected species, can detect and, potentially, avoid colliding with such devices.

Marine ecologist Dr Ben Wilson, who will be supervising the project, said: “This is an exciting opportunity to contribute to both sustainable marine energy extraction and conservation. Scotland is rapidly becoming a magnet for the companies developing devices to capture energy from tidal currents. These machines however will have to share the sea with vulnerable and protected species like whales, seals and fish. Understanding how these animals will perceive and behave around underwater turbines is a mystery but sound will undoubtedly be the most important sense for them, particularly at night and in murky water. Knowing what the natural sound-scape is like in prospective tidal energy sites and the noise output of different devices will help us identify those devices that marine animals will most easily move around without harm. With this understanding we will be better able to promote those machines that have the most gentle ecological footprints.”

The Bush administration’s 8-years of Yellowstone winter use meddling continues to the bitter end: after immediately overturning the Clinton-era phase-out of snowmobiles in the Park during the winter of 2001, it has, in its final month in office, issued a rule to maintain a 720 snowmobiles/day limit, after a year in which the Park Service proposed a long-term cap of 540, then lowered its proposal to 318 when a DC Federal Court tossed its plan as not protective enough.  I took my eye off this ball for a couple months, and it ricocheted around the country, through two Federal District Courts (just as the initial Bush rule did in the middle of this eight years of chaos) and through the businesses and bar-rooms of West Yellowstone, WY, continuing to boggle the journalistic mind to cull the madness into a readable narrative.  The bottom line for this winter appears to be a “limit” of 720 machines, which, if the past few years are any indication, is more than will want to enter the Park (thanks to rules that require all snowmobiles to be part of guided tours).  Read our best attempt at a summary below the fold, or see AEI’s Special Report: Yellowstone Winter Use for ten years of gorey details. Read the rest of this entry »

Responding to a September Federal Court ruling that tossed the 3rd Yellowstone Winter Use Plan on the cusp of a new winter season, Park managers have released a proposed interim plan that will, for the first time since the original Clinton-era plan, reduce the actual numbers of snow machines in the Park on most of the busy winter holidays and weekends. Earlier plans had capped snowmobiles at 720, then more recently, 540 per day; the interim proposal will allow 318 per day. Last winter, an average of 290 snowmobiles entered the park each day, but on many weekends and other peak days, numbers reached 400-500, with the single highest day seeing 557. Read the rest of this entry »

Miller, Solangi, Kuczaj II. Immediate reponse of Atlantic bottlenose dolphins to high-speed personal watercraft in the Mississippi Sound. Journal of the Marine Biological Association of the United Kingdom (2008), 88:1139-1143 [ABSTRACT, CONTACT AUTHOR]

This study, using opportunistic observations in the Mississippi Sound (a 90-mile intercoastal waterway, between the coast and a series of barrier islands; depths up to 20 feet), evaluated the responses of bottlenose dolphins to the appearance of personal watercraft (jetskis). In just under half the incidents, a dolphin group’s behaviour changing within one minute of the presence of a high-speed personal watercraft. The most notable changes were that groups that were feeding shifted dramatically to “traveling”mode. Interestingly, groups of dolphins that were already in “traveling” mode often paused and began “milling.” In addition, mean dive duration increased dramatically, from 12-16 seconds to 42-82 seconds. Researchers note that “The results demonstrated an immediate, short-term change in dolphin behaviour, suggesting that an increase in the frequency of high-speed personal watercraft in this area could produce long-term detrimental effects.” The authors suggest more research into the differences in reactions to high-speed and lower-speed jetskis and the effects of increasing distance of jetski approach; in addition, they note that long term studies of growth and reproduction in places with different densities of personal watercraft would help clarify any population-level impacts that may accumulate over time.

An interesting sidelight to this research highlights the difficulty inherent in almost all field research of cetaceans: the study took place over two years, four days per month, and resulted in 329 encounters with dolphin groups, among which there 137 instances in which a watercraft passed by. However, only 17 of these 137 were suitable for the study purposes (ie, they were high speed personal watercraft, and 10 minutes of video of the dolphins was captured before the watercraft passed). Two years of diligent study resulted in just 17 useable encounters! And, truthfully, n=17 is pretty impressive compared to most cetacean field studes….

The eternal cycle of Yellowstone Winter Use Plans looks to continue for at least one more round, as the third “final” National Park Service rule governing snowmobile access to Yellowstone and Grand Teton National Parks has been tossed out by a Federal District Court after challenges form a consortium of environmental organizations.  DC-based judge Emmet Sullivan found that the NPS plan that would allow 540 snowmobiles to enter the parks each day was “arbitrary and capricious.” Sullivan expressed three key objections: the current average use of 263 snowmobiles is already exceeding the noise standards set by the Park Service (with the additional snowmobiles likely to further increase the area in which snowmobiles are audible for over half the day from 21 square miles to 63 square miles); NPS “utterly failed to explain why none of the seven alternatives would constitute impairment or unacceptable impacts” (despite NPS figures that suggest an increase in exhaust gasses and particulates of 18-100%); and NPS “failed to provide a rational explanation for the source of the 540 snowmobile limit.” The case turned on how to interpret the Organic Act, a 1916 law that established the Park Service

Read the rest of this entry »

A week after the UK’s worst dolphin stranding since 1981, reports from locals and the UK Navy are conflicting. Two weeks of live-fire exercises were wrapping up in the area over last weekend, with the Navy first claiming to have concluded those exercises Sunday afternoon, then saying that in fact the last live-fire took place far offshore on Friday, with a mid-frequency submarine-hunting sonar used on Thursday. However, local Falmouth Coast Guard personnel report heavy Naval activity through Sunday afternoon in Falmouth Bay. And, Nick Tomlinson, a local fisherman working 12 miles offshore, experienced a most dramatic blasts than he has felt in the 35 years he has been working the waters off the Cornish coast. “I’m used to the big military guns going off but this was something different – bang, bang, bang, very close, very loud. The vibrations went through the boat and up through my backbone. The whole boat was shuddering.”
Read the rest of this entry »

Reports of unusual stranding events around the world this week are each triggering questions about possible sonar connections, despite little clear evidence thus far. In Madagascar, over fifty melon-headed whales stranded and died after becoming trapped in a bay; in the UK, 26 common dolphins (mostly juviniles) died along the shores of an estuary river a pod of fifteen strayed into, likely feasting on fish feeding at an algae bloom, with up to seventy more following in the hours that followed, perhaps responding to their distress calls; other dolphins were found dead on two other nearby shorelines within 15km, including another estuary. In Japan, three Cuvier’s beaked whales have been found dead on beaches in the past three weeks, the latest of 81 whale fatalities (9 of them Cuvier’s) since March. Read the rest of this entry »

 A surge in lease sales along Alaska’s west and north coasts has spurred predictable resistance from locals and environmental groups. While the effect of any possible oil spills in harsh waters is certainly a major focus of concerns being voiced, the impacts of the first phase of oil and gas exploration have moved to the forefront of discussions. The oil industry is gearing up to explore a record number of offshore lease areas in the next few years, and this summer, up to five seismic survey vessels are scheduled to be off the Alaskan coast, firing airguns 2-4 times per minute and listening for the echoes Read the rest of this entry »

Bristol Bay Oil and Gas Planning Announced by MMS; CBD Vows to Stop Leasing Process Due to Critical Habitat Designation – The Minerals Management Service has officially announced the start of a planning process to consider a 2011 lease sale for offshore oil and gas exploration in the North Aleutian Basin in Alaska. The publication of the proposal marks the start of the process, which will involve a public comment period and months of gathering information for an environmental impact statement, said Robin Cacy, a minerals service spokeswoman in Anchorage. “No decisions have been made on the sale. This is just the beginning,” she said. The area, which had been protected from drilling since 1990, is north of the Aleutian Islands near Bristol Bay. On the same day that the plan was announced, NMFS published its final decision naming parts of the lease sale as Critical Habitat for the North Pacific right whale. Read the rest of this entry »

Urban Noise Threatens Dawn Chorus and Bird Populations – European researchers are increasingly concerned about accumulating evidence that urban and suburban noise is having dramatic effects on bird populations. Some birds may be adapting by developing new behaviors, perhaps changing dramatically enough to be considered new species: nightengales sing up to 14dB more loudly in the city (some at 95dB, enough to cause discomfort to human ears), great tits are singing at a higher pitch, and robins have abandoned their noisy dawn (i.e. rush hour) chorus and now sing at night, when it is quieter. Birds must hear each other in order to mate and warn each other of predators. Declining populations of house sparrows (down by two-thirds over the past couple of decades) and overall bird populations (down 20% in the past four years) could be due to difficulty in finding mates, or abandonment of urban and suburban habitat.Source: Daily Mail, 3/26/08 [READ ARTICLE]

The latest AEI Special Report takes a close look (or, listen) to the growing concerns about noise impacts from wind farms.  While it appears that only about 20% of wind farms trigger noise complaints, it is crucial that wind energy developers take a close look at these, to assure they don’t repeat the same mistakes.

As usual with AEI Special Reports, the Wind Energy Noise Impacts report is designed to offer a comprehensive yet concise “ten-minute version” of the issue, with links to more in-depth source material.  It includes sections on wind turbine noise, current regulation, comments from neighbors disturbed by noise, possible factors in noise complaints (atmospheric effects top the list), emerging technology, and links to industry trade groups, government agencies, and advocacy groups, both pro and con.

To read or print the report, visit http://www.AcousticEcology.org/srwind.html 

Some excerpts are below the fold:

Read the rest of this entry »

Ship Noise in Santa Barbara Channel Studied – A hydrophone deployed on the ocean floor in the Santa Barbara Channel is listening in on passing ships and resident and transient whales; researchers from Scripps Institute will analyze the results in an effort to learn more about whether increasing shipping noise is hampering whale communication. Blue whales are the most commonly heard, and also the species whose calls occur in the frequency ranges dominated by ship noise. Megan McKenna, doctoral candidate at Scripps, says, “These animals evolved in a much quieter environment. You’ve got to think there has to be some threshold of them being able to use their acoustic capabilities in this noisy environment.”  Read the rest of this entry »