How Navy Sonar Kills Whales and Dolphins

The following excerpts were taken from a letter written by the Biodiversity Legal Foundation, which does an excellent job of explaining how sound kills whales and other forms of marine life:
“Sound penetrates an animal’s body when immersed in water. Essentially all of acoustic energy goes into a body immersed in water. This effect, which can cause tissue rupture and hemorrhage, has not been adequately addressed in the Navy’s [environmental impact statement]. The implications (of the effect of sound penetration) for marine life are very serious, as described next.”
“The first lethal mechanism involves moderate level sound waves activating the growth of microscopic bubbles in the supersaturated blood and tissue of cetaceans. These bubbles then grow and can cause embolisms, hemorrhaging and localized pressure on the nervous system. Significant oxygen deprivation by blood vessel blockage can kill brain cells and produce stroke. For supersaturated gasses dissolved in cells rather than the blood, activation of bubble formation can rupture the cell walls.”
“The second mechanism for lethal injury involves hemorrhaging caused by acoustic resonance of the LFA [Low Frequency Active] sonar signal in cranial and other airspaces such as lungs and swim bladders. Specifically, the rapid change in pressure (from very high to very low several times per second for the duration of the one-minute LFA sonar blast) can rupture the delicate membranes enclosing the airspace.”
“Animals with air filled lungs and swim bladders are especially vulnerable because of the large difference in impedance between air in the lungs or swim bladders and their body tissues or seawater. Submerged animals exposed to explosions at short range showed hemorrhage in the lungs and ulceration of the gastro-intestinal tract.”
“The killing is largely due to resonance phenomena in the whales’ cranial airspaces that are tearing apart delicate tissues around the brains and ears.”
The Navy is accepting public comments on this sonar program until April 27th, 2012, voice your opinion here. You can copy and paste this or write your own comment: “In addition to its impacts on marine mammals and endangered species, I believe that the Navy and NMFS have a responsibility to consider the full extent of the “collateral damage” that will occur with deployment of LFA sonar, and that you must consider the cumulative effects on all forms of marine life that will be adversely affected over areas totaling thousands of square miles. Therefore, the testing and use of this must cease immediately.”

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Hong Kong Airlines bans live dolphin flights.

Hong Kong Airlines has agreed to stop transporting live dolphins after more than 6,500 people signed an online petition demanding a ban.

The airline, which launches all business class flights from the UK next month, had come under sustained public pressure from dolphin lovers, after an internal memo was leaked stating that it had earned £69,000 from transporting five live dolphins from Japan to Vietnam on Jan 16th.

The dolphins are thought to have been from the Japanese town of Taiji, scene of the annual dolphin slaughter depicted in the Oscar-winning documentary The Cove.

This seasons slaughter of dolphins at Taiji is finally over and the Sea Shepherd protestors have done a fantastic job of disrupting things and bringing more world awareness to the problems cetaceans face in the area and the country. The dolphin flesh has been proven to be high in toxins and a danger for any humans to consume.

Over in the US recent dolphin strandings have alarmed researchers who think that a rise in sea temperatures may be to blame. Stranded dolphins, who are most obviously in distress as the weight of their bodies is no longer supported by the ocean , can be senn to calm down appreciably when they are moved close to other dolphins whilst awaiting rescue. Proof once again that these are family groups of sensient beings.

Max

Understanding the sources of ocean noise pollution

The three most significant sources of ocean noise pollution are ship noise, oil and gas exploration and military sonar.

Ship noise
Large international cargo vessels, supertankers and cruise ships are constantly in motion, producing noises from their engines, propellers, generators and bearings.

The problem with this noise is that it dominates the frequency ranges of 20-300Hz, the same range used by many species of whale. This makes it hard for them to communicate and, more dangerously, to distinguish ship noise from natural sounds. The consequence of this is accidental collisions, one of the leading causes of death for right whales around the world.

Ship noise, particularly where it becomes too constant, may also be a cause of some whales abandoning their habitats. The problem is greatest in coastal areas and around busy ports.

Noise from Oil and Gas Exploration and Mining
The oil and gas industry generates loud and continuous sounds through seismic-survey operations, pipeline and platform construction and removal and drilling. This problem is especially bad in the Gulf of Mexico, off the California coast, the Persian Gulf, the North Sea and off the coast of Brazil.

• Exploration noise

So-called ‘airgun arrays’ used to detect oil or natural gas beneath the seafloor use incredibly loud sound pulses directed at geological structures. These are some of the loudest man-made noises in the oceans. Blasted every 10-60 seconds for days or months at a time, these extreme bursts of sound can drive whales away from the area.

• Noise from drilling and extraction

The noise generated by drilling and extraction may not be as loud as the ‘airgun arrays’, but they last much longer. Over time, exposure to these noises can cause whales and other marine species to abandon their habitats.

• Military Sonar

In order to detect submarines over long distances, military sonar systems transmit some of the most powerful underwater noises.

High-energy acoustic pulses are emitted and their echo recaptured as a part of weapon and counterweapon targeting. These high frequency systems (over 10kHz) can transmit pulses of sound for thousands of metres.

So powerful are these noises that whole groups of whales and dolphins can beach themselves to escape the auditory assault. They can also disrupt communication and feeding behaviours and cause temporary hearing loss and permanent tissue damage. As a result, marine mammals are often forced to abandon their preferred habitats.

Cold War-era sonar systems were less dangerous, because they primarily focused on deep-water environments. But today’s sonar systems not only employ new, more powerful technologies but are frequently tested in shallow coastal waters, the same environments that are home to many endangered whales and marine creatures.

Fishery Noisemakers
Not all manmade underwater noises are a bad thing.

To help prevent whales, dolphins and porpoises becoming tangled in fishing gear, some fisheries use underwater noisemakers, known as pingers, to warn of the location of fishing gear.

This new technique has already had some remarkable successes. For example, pingers have significantly reduced the number of harbour porpoise entanglements in the Gulf of Maine.
But while pingers are one source of underwater noise that is meant to be good for whales, we must carefully monitor their use, and be sure they never harm whales or drive them away from their critical habitats.
 

Eureka! The Whaling Fleet Has Been Found and Shut Down!

March 5, 2012

Captain Paul Watson received a Sat phone call from Captain Peter Hammarstedt, on the Bob Barker, at 2200 Hours (AEST) on March 5^th.
“Eureka, Paul, we have the Nisshin Maru in our sights!”
The Nisshin Maru and her three deadly harpoon boats were found at 64 Degrees 59 Minutes South and 130 Degrees 51 Minutes East at Commonwealth Bay, sixty miles off the Antarctic Coast, inside the Australian Economic Exclusion Zone.
The Yushin Maru No. 3 had just arrived from tailing the Steve Irwin. Despite the three harpoon vessels deployed to intercept the Bob Barker, Captain Hammarstedt slipped through their web and gained a visual identification on the primary target.
Two of the harpoon vessels were in pursuit of whales. All whaling activity stopped as the Nisshin Maru began running but the Bob Barker is faster and is gaining steadily on the hated factory ship.
“We have her in our sights and she will not be able to outrun us,” said Bob Barker third mate, Vincent Burke, of Melbourne.
“We have kept them running for two months and that has disrupted their operations considerably but now with the Bob Barker on their stern slipway, whaling is effectively shut down for 2012,” said Captain Hammarstedt (27) from Sweden.
The Japanese security ship, Shonan Maru No. 2, is still tailing the Steve Irwin presently one day from the Bass Strait and is now 1600 nautical miles away from the whaling fleet. The Steve Irwin successfully led the Shonan Maru No. 2 and the Yushin Maru No. 3 away from the Bob Barker to allow the Bob Barker to lose a tailing vessel. The key to finding the Nisshin Maru was losing the tailing ship, and it worked.
“This has been a long and tough campaign, with the worst weather and ice conditions that we have experienced in the entire eight seasons we have ventured into the Southern Ocean Whale Sanctuary,” said Captain Paul Watson. “But despite the temporary loss of our scout ship, the Brigitte Bardot, and our constant dogged pursuit of the Nisshin Maru, we have kept them on the run, taken two of their three harpoon vessels off the hunt for two months, severely crippled their killing capabilities and now once again we have shut them down 100%. Operation Divine Wind has been enormously successful.”

The Bob Barker spots the whaling fleet's factory ship
The Nisshin Maru Photo: Carolina A. Castro

Dolphins are multilingual! Scientists record mammals talking 'whale'... in their sleep

Before we know it they'll be speaking French.

Dolphins are so intelligent they can learn to speak a second language- in their sleep.

Captive dolphins in in Port-Saint-Père, France have been recorded sleep talking, scientists have found.

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Intelligent life: Captive dolphins in in Port-Saint-Père, France have been recorded sleep talking, scientists have found (stock image)

But bizarrely, as they rest at night, the aquatic mammals are not making dolphin sounds but whale-like noises.

Péos, Mininos, Cécil, Teha, and Amtan, who were born in captivity, have only ever heard whale sounds as recordings, Science magazine reported.

If the sounds are confirmed to be ‘whale’, it would be the first known instance of dolphins remembering a particular noise and repeating it 'later', researchers say.

The dolphins have only ever heard a whale sing on the soundtrack to their daily shows at the French aquatic park Planète Sauvage.

 

The 21-minute tape to which they perform features several minutes of whale song among other marine noises.

The dolphins have not been known to mimic the whale song during or after performances, according to Science.

But a nine days and eight nights study between November 2008 and May 2009, revealed  25 occasions of never-heard-before dolphin sounds.
Researchers at the University of Rennes hung underwater microphones in the performing dolphins' tank overnight, Discovery reported.

Paying attention: The dolphins have only ever heard a whale sing on the soundtrack to their daily shows at the French aquatic park Planète Sauvage

 A DOLPHIN'S LIFE

• Dolphins are mammals not fish. They are warm-blooded and feed their young milk
• Swimming in circles while they sleep with the eye on the outside of the circle open allows dolphins to keep watch for predators
• They can dive up to 260m deep and stay under for up to 15 minutes
• They use echolocation in the same way as a radar, to find food and navigate
• Each dolphin has a signature whistle that helps individual dolphins recognise each other and collaborate
• Some researchers have said that dolphins should be treated as non-human persons as they are so intelligent

The unusual noises -which make up just one percent of all the sounds recorded - strongly resemble whale song and occur only during ‘rest periods,’ mainly between midnight and 3 am.
Researchers recruited 20 volunteers to compare dolphin whistles and whale songs and found that the dophin's 'whale' is so good, listeners mistook it for real whale song 72 percent of the time.
The noises suggest that the dolphins could be practising their daily shows in their minds at night.
Martine Hausberger of the University of Rennes 1 told Science: 'The shows are a really special time in the day,' because the dolphins are rewarded for their performance. 'There are lots of things they could mimic but don't. ... It's really remarkable the only mimicry [we] found was this one.'
The recordings are ‘the first report of mimicries of sounds heard during special events produced by dolphins in a resting/sleeping context,’ the researchers wrote in the journal Frontiers in Comparative Psychology December 29, 2011. ‘This finding opens very large perspectives for future investigations on dolphin learning processes and 'mental representations.'

This is of interest to all researchers but maybe just a big sign that dolphins in captivity are having anxiety dreams whilst they sleep and re-living a very bad groundhog day!