Tag Archives: seismic surveys

Mass Dolphin Deaths in Peru Caused by Acoustic Trauma

Mass dolphin deaths in Peru caused by acoustic trauma
BY CANDACE CALLOWAY WHITING     MAY 17, 2012 IN ENVIRONMENT

 [Photo-Image: Dead dolphins discovered on Chiclayo shore of Peru, Photo source: ITN News]
[Photo-Image: Dead dolphins discovered on Chiclayo shore of Peru, Photo source: ITN News]
Dr. Carlos Yaipen Llanos of ORCA in Peru informed Hardy Jones of Blue Voice that acoustical trauma is the cause of the Mass Mortality Event (MME) that killed an estimated one thousand dolphins along the coast of northern Peru in March 2012.
In her article, Hundreds of dead dolphins wash up along the coastline in Peru, Elizabeth Batt describes the devastating loss of the dolphins and porpoises, and the swift action by filmmaker and author Hardy Jones to document the event.
Now the necropsy results are in, and there is unequivocal evidence that the dolphins were killed by an acoustic trauma, such as loud sonar or explosive blasts (more information on potential sources of the loud sound in that region can be found here). Dr. Llanos doesn’t identify the source of the trauma, but all other tests (virus, contaminants, parasites etc) are not considered factors.
The following tissue samples, provided to Blue voice by Dr. Llanos show evidence of rapid ascent, (though the scientists are not willing to speculate on what caused the dolphins to race to the surface, their bodies are adapted to adjust to depth, and normally do not aggregate bubbles in their tissues).
bubbles
Bubbles replaced normal tissue in the dolphin’s liver.
Blue Voice

Likes1

 bubbles 2
A large bubble is compressing a vein and artery in this dolphin’s bladder.
Blue Voice
bubbles 3
The jaw blubber of this baby porpoise is spread by bubbles. The blood vessels show congestion and hemorrhage.
Blue Voice
Necropsies were performed on site. Macroscopic findings include: hemorrhagic lesions in the middle including the acoustic chamber, fractures in the periotic bones, bubbles in blood filling liver and kidneys (animals were diving, so the main organs were congested), lesion in the lungs compatible with pulmonary emphysema, sponge-like liver. So far we have 12 periotic samples from different animals, all with different degree of fractures and 80% of them with fracture in the right periotic bones, compatible with acoustic impact and decompression syndrome.
In a February stranding in the same region of Peru, Dr. Llanos found that:
10 of the 17 animals found dead had broken periotic bones, that is, due to acoustic impact. The source of the impact was from the right side of the pod, since hemorragic internal ear was found in the right side of the stranded animals.
We know that the use of dynamite is common among fishermen, and that fishermen are taking the meat of the stranded dolphins. This could be the cause of death of the animals…however, the signs do not correspond to that of explosive impact in their bodies. We talked today with people from the oil company and they say they haven’t performed any seismic exploration in the area this month. However, here in Peru these companies don’t need to do the seismic assessment themselves.
Update 5/18/12 : Dynamite has been ruled out as a possible cause (via Hardy Jones),
To compare with some of the stranded dolphins Dr. Llanos examined the remains of healthy dolphins that had been stabbed at sea and eaten by the local fishermen and found “intact periotic (ear) bones, (with no fractures), so it was a good “control” sample to compare with previously collected (and fractured) ones.”
Hardy Jones explained to Digital Journal that “traveling to and within Peru is expensive and testing samples from the dead dolphins is very costly, yet highly important.” Blue Voice and Dr. Llanos (ORCA) will continue to investigate the mortality event, and will post updates.

How a few minutes of your time can save a lot of whales [and keep seafood on your table]

Pilot whale stranding in New Zealand Credit: Reuters

The Problem

It’s game-on for offshore drilling in the Atlantic, and it will wreak havoc

Once big oil gets its hooks into the Atlantic seabed there will be no turning back, no way to unwind that clock. Even if they never cause a spill or erect a rig, untold damage will happen to marine life, from the tiniest organisms (see Seismic surveys now proven to kill zooplankton…there goes your crab dinner) to the great whales. And they can’t wait to get started.
The following stranding event caused by ExxonMobil in 2008 is a prime example of the deadly impact of oil exploration.
The story started on a typically breezy and hot day near the mouth of a lagoon on the island nation of Madagascar. Two small whales had beached and died, their gleaming bodies still fresh enough to be eaten by the astonished villagers who carried them off.
But that was just the beginning – the brackish and turbid water of the the Loza Lagoon began to fill with panicked whales swimming desperately away from the ocean world they knew. By the afternoon the deep ocean dwelling melon-headed whales had traveled 65 kilometers (40 miles) inland.

Slowly the lost and confused whales began to die. Amid the tangled mangroves, mudflats and on narrow beaches their skin blistered and their body temperature rose until death came as a reprieve. Impoverished villagers caught and ate an unknown number. Of the estimated 100 -200 melon-headed whales that entered the lagoon only a handful were known to survive, despite a dedicated rescue attempt.
Finally, after nearly a month, four whales were seen leaving the lagoon and heading out to sea.
What had caused the mayhem? After years of meticulous study scientists concluded that the culprit could be summed up in one word: Sonar.
Earsplitting, terrifyingly loud and relentless, the sound had bounced off the underwater cliffs and canyons in the deep ocean. It drove the whales out of their familiar habitat with nowhere to escape until they sought refuge in the lagoon death trap.
It turned out that ExxonMobil and partners were mapping the ocean floor along the coast prior to doing seismic surveys for oil when the stranding occurred, using the type of sonar employed by the navy that had caused the deaths of whales in the Bahamas in 2000. In War of the Whales, author Joshua Horwitz carefully documents the Bahamas strandings but until the sad event in Madagascar no one had be able to document that the private sector – big oil – similarly destroyed marine life.

There is no way to know how many other species were affected and/or died in the ocean or at other remote locations during this one sonar mapping fiasco. And it was expensive – the investments by the scientific community, local officials, and rescue organizations were deep, and because the local population of Madagascar feasted on the toxic meat of the freakishly out of place whales they may experience health consequences.
In the end the whale deaths were for nothing: ExxonMobil and its partners just didn’t find a significant enough puddle of oil hidden under the seafloor to be worthwhile.
And now big oil is poised to repeat their activities off the Atlantic coast of the US. Marine life will have to endure various seismic challenges, from the sonar that drove the melon-headed whales to seek safety where the noise couldn’t penetrate (but for which they were not adapted to survive), to the repeated nearly year long pounding of seismic noise.

WHAT YOU CAN DO

These steps will guide you through the commenting process

NOAA Fisheries wants the public to weigh in on this – the oil companies can’t operate seismic surveys unless they get permits from the energy bureau, and the energy bureau won’t issue permits unless NOAA is satisfied that existing restrictions are met.

  1. Go to the Federal Register website and familiarize yourself with the process.
  2. Choose current research to support your comments.  (The links below are studies published in 2017 and either were done in the region specified or include species known in the specified area.)
  3. Email your comments to:  ITP.Laws@noaa.gov by July 6th.

But remember, NOAA will NOT consider comments other than as specified. “We will only consider comments that are relevant to marine mammal species that occur in U.S. waters of the Mid- and South Atlantic and the potential effects of geophysical survey activities on those species and their habitat.”
Suggested links:
Natural and anthropogenic ocean noise recorded at long-term and temporary observatories
High suckling rates and acoustic crypsis of humpback whale neonates maximise potential for mother–calf energy transfer
Cetacean sightings and acoustic detections during a seismic survey off Nicaragua and Costa Rica, November-December 2004
Nowhere to go: noise impact assessments for marine mammal populations with high site fidelity
 

Background information:

Having removed the protections against drilling along the Atlantic Coast put in place by then President Obama, the Trump administration is trying to push NOAA Fisheries to use the old, lower standards for sound levels rather than the new standards that were set to start this year. And they want the permits to be expedited so that the oil companies can start the seismic surveys as soon as possible.
From Trump’s executive orderImplementing an America-First Offshore Energy Strategy

Sec. 9. Expedited Consideration of Incidental Harassment Authorizations, Incidental-Take, and Seismic Survey Permits. The Secretary of the Interior and the Secretary of Commerce shall, to the maximum extent permitted by law, expedite all stages of consideration of Incidental Take Authorization requests, including Incidental Harassment Authorizations and Letters of Authorization, and Seismic Survey permit applications under the Outer Continental Shelf Lands Act, 43 U.S.C. 1331 et seq., and the Marine Mammal Protection Act, 16 U.S.C. 1361 et seq.
Sec. 10Review of National Oceanic and Atmospheric Administration (NOAA) Technical Memorandum NMFS-OPR-55. The Secretary of Commerce shall review NOAA’s Technical Memorandum NMFS-OPR-55 of July 2016 (Technical Guidance for Assessing the Effects of Anthropogenic Sound on Marine Mammal Hearing)… take all steps permitted by law to rescind or revise that guidance, if appropriate.

 

References and further reading:

Seismic surveys now proven to kill zooplankton…there goes your crab dinner

Like many marine fishes, this baby puffer fish drifts with the ocean currents during its larval stage

Love lobster? Crab? Swordfish? The larvae (just hatched) stages of these tasty marine species spend their early development floating as part of zooplankton community. Their limited ability to move means that they drift wherever the currents take them, leaving them uniquely vulnerable and unable to escape devastating events such as oil spills or even just the noise associated with searching for new offshore oil reserves.
Baby sailfish

Published today in Nature, the science is in – the noise from the airguns used in seismic exploration for offshore oil has been shown to have devastating effects on zooplankton. The team of researchers found significant damage to zooplankton up to 3/4 mile away from the source:

Experimental air gun signal exposure decreased zooplankton abundance when compared with controls, as measured by sonar (~3–4 dB drop within 15–30 min) and net tows (median 64% decrease within 1 h), and caused a two- to threefold increase in dead adult and larval zooplankton.

Lobster larvae

Impacts were observed out to the maximum 1.2 km range sampled, which was more than two orders of magnitude greater than the previously assumed impact range of 10 m. Although no adult krill were present, all larval krill were killed after air gun passage.
There is a significant and unacknowledged potential for ocean ecosystem function and productivity to be negatively impacted by present seismic technology.

Octopus larva

The significance and implications of potential large-scale modification of plankton community structure and abundance due to seismic survey operations has enormous ramifications for larval recruitment processes, all higher order predators and ocean health in general.
There is an urgent need to conduct further study to mitigate, model and understand potential impacts on plankton and the marine environment, and to prioritize development and testing of alternative seismic sources.

Swordfish larva

Plankton also supply half of the oxygen we breathe and are the base of the ocean food web – with less plankton there is less for fish to eat at a time when the world is increasingly looking to the ocean to provide food.
The planned seismic surveys off the Atlantic Coast of the US will have negative effects on the marine life, and eventually will impact the distribution and abundance of seafood. And if you like to fish, you may find it even harder to hook a big one.
NOAA is taking comments until July 6th on the proposed seismic surveys in the Atlantic.
Blue marlin larva

 

Exxon Mobil CEO Sues to Keep Fracking Project Away From His Property, But Supports Fracking Elsewhere

Exxon Mobil, the company who brought us the disastrous  Exxon Valdez spill in Alaska (which they have yet to pay for), and more recently the tar sands oil spill in Mayflower, Arkansas, were also found to be responsible for the death of 100 melon-headed whales in Madagascar during offshore oil exploration. The company continues to explore for petroleum resources worldwide, often against the wishes of local communities such as the current conflict in South Africa.
1066801_884251 humpback dolphin south africa“Durban environmental activists have vehemently rejected an application by multi-national energy giant ExxonMobil to explore for oil and gas offshore along the KwaZulu-Natal coastline, citing the company’s poor environmental track record as a major concern.” (4 Traders)
Fracking, or hydraulic fracturing, is opposed by many environmental groups because the process is associated with degradation of local water quality and health concerns.  The process is described in this brief video:

But apparently more important than the environment, human rights, and ocean life to the CEO of Exxon Mobil, Rex Tillerson, is the view from his multi-million dollar property. For that, he demands to be an exception from the consequences of his company’s activities and somewhat bizarrely and hypocritically has joined in a lawsuit to block the construction of a water tower associated with fracking near his ranch.

In shale regions, less wealthy residents have protested fracking development for impacts more consequential than noise, including water contamination and cancer risk. Exxon’s oil and gas operations and the resulting spills not only sinks property values, but the spills have leveled homes and destroyed regions.
Tillerson has joined a lawsuit that cites fracking’s consequences in order to block the construction of a 160-foot water tower next to his and his wife’s Texas home.
The Wall Street Journal reports the tower would supply water to a nearby fracking site, and the plaintiffs argue the project would cause too much noise and traffic from hauling the water from the tower to the drilling site. The water tower, owned by Cross Timbers Water Supply Corporation, “will sell water to oil and gas explorers for fracing [sic] shale formations leading to traffic with heavy trucks on FM 407, creating a noise nuisance and traffic hazards,” the suit says.
Exxon, which pays Tillerson a total $40.3 million, is staying out of the legal tangle. A spokesperson told the WSJ it “has no involvement in the legal matter.” (Think Progress).

Not in his backyard!  Exxon  Mobil CEO Rex Tillerson is suing to keep fracking project away from his ranch.
Not in his backyard – Exxon Mobil CEO Rex Tillerson is suing to keep fracking project away from his ranch, but is paid well to ensure that these projects succeed elsewhere.

Seismic Survey Ship Forced Off of Fishing Grounds by a Flotilla of Small Boats

“We don’t just want to hear about meagre compensation for our financial hardships. We want to fish, living the way we’ve lived for thousands of years. This is our legacy, our right and what we know best. It seems to be a case of feeding the rich and depriving the less privileged. We are scattered all over Trinidad and Tobago which makes it easy to divide, fool and conquer us to get us out of their way as they have done just last week with our fellow fishers on the south coast, who accepted the untruths and inadequate packages dangled at them, as we once did, because of their financial distress and ignorance, just as ours, distress which is counted on to weaken our resolve and fool you, the public.” Diane Christian-Simmons
 
2013-11-20-DSCN49731DianeChristian.jpg
Photo courtesy of Diane Christian-Simmons.
Fed up with trying to work through government channels, the fishing community of Trinidad Tobago has held a series of peaceful pickets to protect the fish that have fed their nation for thousands of years – fish that are known to be harmed by oil companies in the seemingly unquenchable offshore quest for oil and gas.
A research article (see page 205) speculates that humpback whales have not returned to that area because of the noise associated with the activities of oil companies, and the whales and dolphins of that region will also benefit by enforcing environmental constraints on big oil.

Photo courtesy of Newsday.
Photo courtesy of Newsday.

Now that the seismic surveys – which bombard the environment with loud noise for weeks or months at a time – have begun in spite of the fishing community demands, the fishermen decided to take their protest to the waves, and two dozen or so small fishing boats dodged police boats and slowed the huge seismic vessel.
According to the Caribbean New Media Group, a cat and mouse game ensued as the oil company police boats tried to block the local fishing boats, called “pirogues”:

Even with faster, bigger and more powerful vessels, the efforts of Petrotrin Police were frustrated. They could halt the progress of a pirogue or two, but they could not stop them all.
Several fishermen told C News they were prepared to face guns if need be to protect the fishery. But on Saturday morning, the only thing pointed in their direction from the authorities were cameras.
The convoy of fishing boats continued their pursuit of one of the ships being used in the seismic survey, with the Petrotrin Police boats in hot pursuit.
The police boats used their powerful engines to churn up wake, crossing in front of the bows of the smaller fishing boats to slow them down.
Coincidentally, it was a tactic that the fishermen planned to use as well. Using their greater numbers, they found their way into the path of the seismic survey ship and slowed their pace, forcing the ship to slow to a crawl to match their pace and allow the ship’s captain a chance to think of his next move.
Mr. Gary Aboud of Fishermen and Friends of the Sea said: “He cannot stop because the cables are in the water. He is doing the bombing already. But it is illegal so we are going to go in front the ship and stop it. But you have to be ready to pull out at a moment’s notice because the ship cannot stop.”
A maritime cat and mouse game ensued as the seismic survey ship turned and sped over to areas uncovered by the pirogues and Petrotrin’s Police offered whatever resistance they could muster to slow down the pursuit.

Eventually the seismic ship, the Sanco Star, was forced into rougher water where the small boats could not follow.
From a post I wrote last fall, explaining the significance of the problem fisheries have with the seismic search for oil:
Last November, a peaceful picket resulted in the dramatic arrest of Gary Aboud, head of Fishermen and Friends of the Sea (FFOS), environmentalist Cathal Healy-Singh and La Brea fisherman, Wayne Henry.
Gary Aboud, head of Fishermen and Friends of the Sea (left), Diane Christian-Simmons, president of the Cocorite fishing association (center), and environmentalist Cathal Healy-Singh (right). This statement accompanied the press conference.
The situation in Trinidad Tobago is particularly complex because that well-educated nation enjoys a good standard of living in many sectors as a result of the extensive oil reserves that have built the economy, and which created a government that is closely tied to the industry.
In a press release, Fishermen and Friends of the Sea note that the Environmental Management Authority (EMA) has never required Environmental Impact Assessments (EIA) before seismic surveys for oil and gas are undertaken. They understand that oil exploration will undoubtedly occur there, but they are requesting something very significant: They just want basic science to figure out the degree of impact on fisheries, and they want the fish stock restored.
2013-11-20-DSCN49721DianeChristian.jpg
“Bombing” is a colloquial term for the seismic surveys, the fishermen (colloquially referred to as ‘fisherfolk’) understand the science of seismic surveys. Photo courtesy of Christian-Simmons.
The fishing community demands reasonable compensation from the oil industry for loss of income. The next oil survey will keep them from the area for eight months, and studies show that the fish may disappear from the region due to the noise.
Arrested in last week’s protest, environmental engineer Cathal Healy-Singh has documented the situation there in detail, and provided the information to the government.

There is a plethora of scientific data worldwide which concludes that Seismic Surveys (SS) are damaging to not only marine mammals but also to fish and other marine organisms. In 2011, Fishermen and Friends of the Sea, presented to the EMA (and all relevant government agencies and fishing groups) a substantial technical document which compiles the results of scores and scores of research papers from scientific groups around the world which clearly and unequivocally recognizes the damage that SS does. “During the last 20 years there has been growing concern with respect to the impacts of offshore SS activities on marine life”

From the press release:

Since they [EMA] failed to require EIAs in the past, there is no documented evidence of where, how much and what types of fish are being caught, and what the impacts of previous specific Seismic Surveys have been on national fisheries and particularly commercial fisheries, since only the landing sites and gross quantities caught are intermittently documented by the Fisheries Division (according to fishermen).As a result, the EMA is not in a position now, nor will they be after the Guidelines are written, to “ensure that offshore activities are conducted in a regulated manner”. Hence they would have failed to “uphold principles of sustainable development”
Everyone is now fully aware of the grave concerns of fishermen forced, precisely because of a lack of consultations, to have to come into the full public gaze and demonstrate peacefully at the POS waterfront. They are reporting up to 70% drop in catch; lasting months after the Seismic Surveys are completed.

NOAA’s New Noise Guidelines for Marine Mammals – What You Need to Know

In order to make comments on this draft during the next 30 days, you can view the document here (note: there is a list of acronyms on page VII, and a glossary of terms on page 61 – both very helpful!) then place your comment here (which is document  NOAA-NMFS-2013-0177). You have until January 26th, 2013.
Please remember, NOAA will only take seriously comments that address the specific document, which in this case is the science behind the numbers but is also the lack of a broader scope.  NOAA promises to release the peer reviewer reports and NOAA’s response to those reports, but they are not up at the present time.
article-2449077-18956B9700000578-858_634x430 pilots in spain
By the title “Draft Guidance for Assessing the Effects of Anthropogenic Sound on Marine Mammals“, you might think that NOAA is establishing guidelines for assessing the effects of anthropogenic (manmade) sound on marine mammals.  Guess again.
The promise:

 This guidance is intended to be used by NOAA analysts and managers and other relevant user groups and stakeholders, including other federal agencies, when seeking to determine whether and how  their activities are expected to result in particular types of impacts to marine mammals via  acoustic exposure.

What they deliver:

This document outlines NOAA’s updated acoustic threshold levels and  describes in detail how the thresholds were developed and how they will be revised and updated in the future.

Not included:

NOAA currently is in the process of developing  new thresholds for onset of behavioral effects. When that process is completed, TTS [Temporary Threshold Shift, which are temporary hearing losses] will be  addressed for purposes of take quantification. In the meantime, the TTS thresholds presented represent the best available science and will be used in the comprehensive effects analyses under the MMPA [Marine Mammal Protection Act} and the ESA [Endangered Species Act] and may inform the development of mitigation and monitoring.

In other words,the draft does not cover behavior in any new way, and disregards any science that correlates certain types of sound with strandings and deaths, nor does it address the compounding effect of so many sources of noise invading the marine environment for lengthy time periods.
It is a myopic look through the lens of hard science on how sound effects different species of marine mammals, and although it is based on solid science the data points are few, and NOAA set clear guidelines for updating as new research is published.
Having so little data available, NOAA basically relies heavily on Marine Mammal Noise Exposure Criteria:  Initial Scientific Recommendations in setting the guidelines for PTS (Permanent Threshold Shift, which is permanent hearing loss):

Thus, NOAA accepts the recommendation made by Southall et al. (2007) as guidance for determining PTS onset for impulsive signals for all cetacean [dolphin, porpoise, whale] and underwater pinniped [seals, sea lions, walruses) species, resulting in an approximate 15 dB difference between TTS [temportary] and PTS [permanent] onset.

That study was published in the journal Aquatic Mammals, which is “Supported through Joint Sponsorship by the European Association for Aquatic Mammals, the Alliance of Marine Mammal Parks and Aquariums,
and the International Marine Animal Trainer’s Association.”
From a technical standpoint  NOAA’ draft is a huge step forward in delineating more species-specific guidelines, yet there are no teeth in the document to force compliance with the new standards.

 NOAA recommends that Federal agencies and prospective  applicants evaluating these types of impacts for the purposes of engaging in the aforementioned statutory processes also use these thresholds in the manner described here. However, this guidance does not create or confer any rights for or on any person, or operate to bind the public. An alternative approach may be proposed (by Federal agencies or prospective applicants) and used if case-specific information/data indicate that the alternative approach is likely to produce a more accurate estimate of Level A Harassment, harm, or auditory injury for the project being evaluated and if NOAA determines the approach satisfies the requirements of the applicable statutes and regulations.
The National Research Council (NRC 2004) provided basic guidelines on National Standard  (NS2) under the Magnuson-Stevens Fishery Conservation and Management Act, section 301, which stated “Conservation and management measures shall be based upon the best scientific information available.” They recommended that data underlying the decision-making and/or  policy-setting process be: 1) relevant, 2) inclusive, 3) objective, 4) transparent and open, 5) timely, 6) verified and validated, and 7) peer reviewed.

Of the ten candidates for peer review, NOAA selected four, all specialists in the ability of marine mammals to hear. None of the behavior experts were included, and no one addressed the effect of sound on the animals outside of the hearing structures themselves – so tissue damage resulting directly from noise, or from rapid decompression during escape from sound sources are included.
 
delfin_1

The following website contains updated information on the peer review process including: the  charge to peer reviewers, peer reviewers’ names, peer reviewers’ individual reports, and NOAA’s response to peer reviewer reports http://www.nmfs.noaa.gov/pr/acoustics/guidelines.htm.

Below are some samples from the document – which, while long, is logically laid out and easy to navigate (but very science dense).

NOAA has compiled, interpreted and synthesized the best available science to produce new thresholds for the onset of both temporary and permanent hearing threshold shift (“TTS” and  “PTS”, respectively) in marine mammals from underwater sound. In the regulatory context, NOAA uses this information to help quantify “take” and to conduct more comprehensive effects analyses under several statutes.
For applicants/users that have the ability to model moving animals and/or  sources and the accumulating sound at each receiver, NOAA proposes that 24-hours or the length of activity, whichever is less, be used as the accumulation time. 24 hours has been used in other noise assessment planning applications (e.g., community noise planning for aircraft, vehicular traffic, and railway noise) and provides a reasonable outer bound in situations where the model will be able reflect realistic changes in relative distance between the source and likely exposed marine mammals over the course of a day.
However, for models that do not incorporate animal movement, it is not appropriate to make the assumption that animals will remain at a constant distance from the source accumulating acoustic energy for 24 hours. Additionally, if sound accumulation cannot be modeled, an alternative method must be used. For situations where modelling of movement and sound accumulation are not possible, an alternate method that is intended to address the accumulation of sound energy over time, but instead provides a distance from the source (“SEL threshold distance”) that is  simpler to apply in exposure modeling (i.e., would be used in calculations in the same way distance is used to calculate exposures above previous NOAA sound pressure level thresholds) should be used. Based on what we know about typical animal movement and avoidance, we propose a 1-hour accumulation period be used to calculate the “SEL threshold distance”. This “SEL threshold distance” is calculated by determining the distance from the source at which an animal would have to remain for 1 hour in order to accumulate sound to the designated threshold.  While, animals may move closer and farther from the source, this distance is considered a reasonable and conservative approximation.
The 24-hour (for models able to account for movement and sound accumulation) and 1-hour (for models not able to account for movement and sound accumulation) accumulation periods are considered a conservative baseline for accumulation time under most situations. The use ofmodels able to account for movement and sound accumulation may also allow for the inclusion of additional details to provide a more realistic results based on the accumulation of sound (e.g. information on residence time of individuals, swim speeds for transient species, or specific times when activity temporarily ceases). Alternatively, there may be case-specific circumstances where the 1-hour accumulation time should be modified to account for situations where animals are expected to be in closer proximity to the source over a notably longer amount of time, based on activity, site, and species-specific information (e.g., where there is a resident population in a small and/or confined area and a long-duration activity with a large sound source, or a continuous stationery activity nearby a pinniped pupping beach).
NOAA’s previous acoustic threshold levels are expressed as root-mean-square (dBrms), which  uses a different metric from peak sound pressure levels (dBpeak) and SELcum that are being recommended for our TTS and PTS onset acoustic threshold levels. Thus, we recommend caution when comparing past acoustic threshold levels to the acoustic threshold levels presented in this document as because they are based on different metrics, they are not directly comparable. For example, a 180 dBrms level is not equal to a 180 dBpeak level. Furthermore, theSELcum metric incorporates time and is an energy level with a different reference value (re: 1μPa2-13 s), thus it is not directly comparable to other metrics that describe sound pressure levels (re: 1 14 μPa).

 
 

To Protect Dolphins and Whales, Look Behind the Masks of Industry

FacebookphotoOfWolfhunters

“Fed Up in Wyoming” reads the caption under this stunning photograph posted on a hunter’s Facebook page (reproduced here under Fair Use). The photo is yet more evidence that, two years after political reactionaries led a successful campaign in the House of Representatives and then the Senate to remove the North Rocky Mountain gray wolf from the endangered species list, the slaughter of wolves continues to escalate as wolf hunters fall deeper in their paranoid fantasy that the wolf represents a liberal conspiracy against rural communities. (Earth Island)

You may be wondering what shooting wolves in the Rocky Mountains has to do with marine mammals, and the answer is that even though most of what people do to marine mammals occurs out of sight in the open ocean or underwater, the perpetrators are equally hesitant to show their faces as are these wolf killers. Standing up for your beliefs carries risks – someone, somewhere, is guaranteed to oppose your point of view – but hiding behind masks and walls of paperwork only serve to show an awareness of the wrongdoing.

 [Photo-Image: Dead dolphins discovered on Chiclayo shore of Peru, Photo source: ITN News]
[Photo-Image: Dead dolphins discovered on Chiclayo shore of Peru, Photo source: ITN News]
Out in the oceans, fishermen consider dolphins and whales to be competitors or bycatch (unintended when fishing)  and willingly kill them, the animals get tangled in crab and lobster pots or fishing nets, and are hit by ships. The ambient noise levels in the ocean is continually rising, interfering with the whale’s long-range communications. Navies worldwide engage in espionage and mock warfare movements involving loud sonar, and bombing practice occurs over wide swaths of the ocean.
Nations continue to hunt whales and dolphins for meat while pretending it is for scientific research. The oceans are increasing polluted with effluent and plastic debris. Our demand for oil has resulted in devastating spills, and nearly constant deafening sound from seismic surveys.
Seven orcas stranded in Australia, two died (http://www.brisbanetimes.com.au/environment/whale-watch/wildlife-rangers-watch-over-pod-of-whales-that-were-stranded-near-fraser-island-20130703-2pbia.html)
Seven orcas stranded in Australia, two died (www.brisbanetimes.com.au)

There is no escape for whales and dolphins, other than to cast themselves on our beaches, which they appear to be doing in increasing numbers.
Unlike the wolf killers, the masks worn by the perpetrators of ocean destruction are more subtle – they hide behind international partnerships that protect them from each country’s laws. Currently Exxon/Mobil and BP are teaming up with Canada’s Imperial Oil to drill in the Arctic, and even though Exxon/Mobil is a U.S. corporation, they have a Canadian subsidiary and also own controlling interest in Imperial.  The upshot? Environmental protections that are drastically more lenient than the U.S., and where the only consideration given to marine mammals is in how the indigenous population will be effected in their hunts. 
canada oil eis
Perhaps most insidiously, they are hiding behind the issues that frighten us most – climate change, energy shortage, and the threat of losing all that we have spent lifetimes building. An example of this occurred last March when a pod of orcas were trapped in the ice at Hudson’s Bay, thought to have been caught off guard by shifting ice patterns. While this shift in conditions was initially blamed on climate change, it turns out that the local power company is probably responsible:

“There’s a connection between the freshwater plumes sent into Hudson Bay from the Quebec power corporation’s huge dams and the quick freezing of water in the bay which led to entrapments of eiders, beluga and killer whales this past winter, suggests Joel Heath, a biologist whose film People of the Feather about Sanikiluaq hunters and eider ducks, received acclaim.
The connection is worth studying, he said, because although entrapments occur naturally, this past winter there were at least three occurrences in southern Hudson Bay.”

Wherever people are hiding behind masks, covering their tracks, or working below the public radar, a price is paid and the world as we know is quietly being changed.

Pilot whales attempting to strand in Scotland, September 2013.  They were guided back to sea.
Pilot whales attempting to strand in Scotland, September 2013. They were guided back to sea. (Huffington Post)

The good news is that although it may seem as though we are powerless to bring about change, we are not – an International Dolphin and Whale Stranding Network is being created which will keep track of sightings of injured, stranded, and dead whales and dolphins on a global scale.  This will make it difficult for industry and military to deny the impacts of their activities, and it will help provide data to scientists to help determine why there are alarming numbers of dolphins and whales beaching and dying.

Overall, the experts pointed out that the dead dolphins may be alerting us to troubles in our oceans.

Said NOAA’s Spradlin, “Marine mammals are like the canary in the coal mine”—many bottlenose dolphins live on the same coasts and eat the same fish that we do.
“Our first mandate is to protect the dolphins, but the underlying bigger picture is if things are hurting these animals,” he said, “[they] could also be hurting people as well.”

While an outbreak of morbillivirus (related to measles) is known to be responsible for some of those dolphin deaths, it is important to be aware that there could be other causes as well, and not let the disease create a smokescreen. The scientists need our support. For more information, please visit the International Dolphin and Whale Stranding Network.