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Japan, UK, Madagascar Strandings Spur Sonar Speculation

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

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 »

Navy Complains About Varying Sonar Rules

News, Sonar No Comments »

After routine pre-deployment training exercises in Hawaii, some Navy personnel have complained that the differing operational requirements imposed by federal courts in Hawaii and California are complicating, and at times compromising, their mission. Rear Adm. James P. “Phil” Wisecup, commander of the strike group, said the changing sonar rules “just complicate things” in a warfare area that’s already very complex. “In the end, just give me a standard, and I can meet it,” Wisecup said, “But if the standard changes — and it is changing from one area to another — as different judges interpret the law and make decisions on a very complex issue — then we have to adapt.” Read the rest of this entry »

SoCal Sonar Draft EIS: Navy Sticks to its Approach

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Navy Releases Southern California Sonar Draft EIS, Proposals Fall Short of Court Orders - The Navy has released its long-planned Draft Environmental Impact Statement on offshore training exercises in Southern California, including the use of mid-frequency active sonar. Recent legal challenges to the Navy training, in which a circuit court judge imposed additional restrictions on use and an appeals court upheld the ruling, have been based on both the Navy’s previous lack of comprehensive environmental analysis, and on the standing of the California Coastal Commission to impose its own restrictions beyond those imposed by the federal National Marine Fisheries Service. The DEIS continues to make the case that the Navy’s existing operational procedures, developed in consort with NMFS, provide adequate protection to marine life; California state officials and laywers told the press that they are likely to challenge the final EIS if additional safety measures are not added.  Read the rest of this entry »

Navy Asked Supreme Court to Rule on Sonar Restrictions

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Navy Looks to Supreme Court for Sonar Relief - The US Navy has, as widely expected, asked the Supreme Court to review a decision by a Federal Appeals Court that upheld a lower court ruling imposing a larger buffer zone and other additional operational restrictions on its sonar training in southern California. The Justice Department petition argues that the restrictions jeopardize the Navy’s ability to train sailors and Marines for service in wartime, and could possibly prevent certification of some naval strike groups preparing to deploy to the Persian Gulf. The agency also contends that national security interests can trump those of marine mammals, and that its use of mid-frequency sonar in training exercises hasn’t caused any documented harm to dolphins or beaked whales in the waters where they’re conducted. “We believe that this is an issue that is absolutely essential to national security and that a Supreme Court review of this case is warranted,” said Cmdr. Jeff Davis, a Navy spokesman.  Read the rest of this entry »

CA Appeals Court Upholds Most Sonar Restriction

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California Appeals Court Hands Navy Sonar Setback; Supreme Court May be Next - The 9th U.S. Circuit Court of Appeals on Friday night rejected the Navy’s appeal of restrictions that banned high-powered sonar within 12 nautical miles of the coast and set other limits that could affect Navy training exercises to begin this month. One of the key measures upheld by the court was the maintenance of a 2200-yard safety zone, with sonar being shut down if a whale enters that radius; the Navy called for a 200-yard shut-down zone, with power-reductions starting only when a whale came within 1000 yards. Read the rest of this entry »

Hawaii Court Imposes Additional Mitigation on Sonar Trainings

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Hawaii Court Adds Restrictions to Navy Sonar Training - A Federal District Court in Hawaii has issued a preliminary injunction forcing the Navy to use additional safety measures during routine mid-frequency sonar training in Hawaii waters; Judge David Ezra will hold another hearing in April to consider long-term measures. The restrictions are slightly less strict than those imposed by a different District Court in California: Ezra increased the safety zone in which sonar must be powered down by 6db, from the Navy’s 1000m to 1500m, and sonar must be shut down if a whale is within 500, rather than 200m as they Navy planned.  Read the rest of this entry »

Hawaii Navy DEIS hearings in March

News, Ocean, Sonar No Comments »

Public Hearings Scheduled on Supplement to Draft EIS - The Navy has released a supplement to its Draft EIS for the Hawaii Range Complex, and is holding public hearings in March to collect public comments on the new aspects. Plans still hold to release the final EIS this spring, and a Record of Decision before the summer RIMPAC exercises. The supplement addresses several areas: fine-tuning of the methodology used to assess behavioral responses to sonar sounds, a lower estimate of total sonar use, and a new preferred alternative in which future sonar use will not increase over current levels, while other training is expanded as planned.Source: Hawaii Reporter/Pacific Fleet Press Release, 2/23/08 [READ PRESS RELEASE]

Deepwater dolphin strands during SoCal sonar exercises

Ocean, Sonar No Comments »

Dolpin Strands on Navy Island at End of Recent Sonar Exercises - A single deep-water Northern right whale dolphin was found live-beached on San Nicolas Island on January 29, during a heavily scrutinized Naval training exercise. Navy personnel returned it to the water several times, but it did not survive. Curators at the Santa Barbara Museum of Natural History worked all night to perform a necropsy because clues are lost to rapid decomposition. The head was removed and refrigerated, then taken to the nearby Alamo Pintado Equine Medical Center for magnetic resonance imaging. “At this point, we cannot rule in or rule out sonar or any other kind of intense noise,” said Teri Rowles,  Read the rest of this entry »

Judge rejects sonar exemptions

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Federal Judge Rejects White House Exemptions for CA Sonar (updated 2/19)- The federal judge who imposed additional safety requirements on Naval mid-frequency active sonar training off the California coast has rejected the Bush administration’s attempt to exempt the Navy from the laws she was enforcing. Central to this ruling is the fact that there is no “emergency” that warrents such intervention by the White House; the training missions at issue have been long planned, and can proceed, albeit with larger safety buffers and some geographic restrictions to avoid areas with higher numbers of whales.

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LFAS Challenged Again

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Court Forces Navy to Meet With NRDC to Limit LFAS Deployment, Again - In August, the Navy received a 5-year permit to operate its Low-Frequency Active Sonar system on two ships, nearly anywhere in the world, after several years during which its deployment was limited to a remote area of the West Pacific. This week, the same Federal Judge who ordered the earlier reduction in deployment issued a temporary restraining order calling on the Navy to keep its LFAS signals out of several sensitive marine areas worldwide, and to once again sit down with the NRDC and its allies to hammer out a mutually agreeable set of restrictions for the coming five years.  Read the rest of this entry »

Beaked Whale Controlled Exposure Study Begins

Ocean, Sonar No Comments »

Controlled Exposure Study Examines Beaked Whale Responses to Noise - A multi-year research program based at a Navy facility in the Bahamas is using hydrophones installed on the seafloor, along with suction-attached tags that record the sound heard by tagged whales to learn more about how dive patterns are changed when whales hear mid-frequency sonar signals. The Woods Hole periodical Oceanus featured a detailed article on this work, including pictures. Oceanus, 1/15/07 [READ ARTICLE] See also AEI’s lay summary of the cruise report from their first field season[GO THERE]

Beaked whale controlled exposure study

Science, Sonar No Comments »

Initial Cruise Report From First Controlled Exposure Studies of Beaked WhalesIan Boyd, Diane Claridge, Christopher Clark, Brandon Southall, Peter Tyack. Behavioral Response Study-2007, Cruise Report, Phase 1    A summary of the project, and the preliminary cruise report are available: [WEBSITE]During August and September, 2007, the first controlled exposure experiments aimed at learning more about the ways that beaked and pilot whales respond to exposure to mid-frequency active sonar took place in the Bahamas.  Read the rest of this entry »

Beaked whales fleeing near surface at risk for bends?

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Extended Near-surface Dives May Be Cause of Beaked Whale BendsWalter, M.X. Simmer, Peter L. Tyack. Repetitive shallow dives pose decompression risk in deep-diving beaked whales. Marine Mammal Science, Volume 23 Issue 4 Page 888-925, October 2007.  ScienceNow summary of paper: [WEBSITE]It is apparent that beaked whales are especially sensitive to mid-frequency sonar, but the reasons have remained elusive. This study explores a new idea about how the whales’ dive patterns may be disrupted enough to cause decompression sickness (DCS, ie “the bends”). Some have suspected that exposure to sonar may cause the whales to surface more quickly than usual, but since the whales’ lungs are collapsed in dives deeper than 70m (thus preventing nitrogen from entering the bloodstream and infiltrating into tissues where it could cause damage), it is not readily apparent how faster surfacing would cause DCS. Instead, this study looks at the “recovery” period observed in beaked whales, during which they make a series of near-surface dives before embarking on a new deep foraging dive. The researchers modeled the possible physiological effects of having this recovery period extended longer than usual. The team incorporated known physiological data into a model that charts how the bubble size might increase in the circulatory system, brain, muscles, and fat tissues when a whale dives repeatedly to between 30 and 80 meters for as long as 3 hours. The team’s model predicts that if the whales’ lungs do not collapse during a long series of shallow dives, the increased pressure can cause nitrogen bubbles to diffuse into tissues, increasing the risk of bubble formation on ascent. Such behavior may result if the whales perceive sonar transmissions as a predator:  Read the rest of this entry »

LFAS effects on fish hearing

Science, Sonar No Comments »

Low Frequency Active Sonar Shows Less Impact on Fish than Airguns  

Popper, Halvorsen, Kane, Miller, Smith, Song, Stein, Wysocki. The effects of high-intensity, low-frequency active sonar on rainbow trout. J. Acoust. Soc. Am. 122 1 , July 2007. p. 623-635.
This study extended a previous line of research that had measured physiological impacts of seismic survey air guns on fish kept confined in a cage and exposed to the noise. This time, the research team exposed trout (which share hearing mechanisms with salmon, which are of special concern due to their endangered status) to sounds produced by low-frequency active sonar. LFA sonar uses frequencies (100-500Hz) that many fish can detect, often the range of most sensitive hearing. Fish were tested for hearing sensitivity using Auditory Brainstem Response (ABR), and some were sacrificed to check for physiological damage, including swim bladder or ear hair damage. Results indicate that fish had reduced hearing sensitivity after exposure to LFA sonar, ranging from 17-25dB at particular frequencies (i.e., sounds needed to be that much louder in order to be heard), and that the effects lasted at least 48 hours (the longest followup the study included). 

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