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For some whales, sonar may provoke suicidal behavior: study

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Scientists have long known that some beaked whales beach themselves and die in agony after exposure to naval sonar, and now they know why: the giant sea mammals suffer decompression sickness, just like scuba divers.

At first blush, the explanation laid out Wednesday by 21 experts in the Royal Society journal Proceedings B seems implausible.

Millions of years of evolution have turned whales into perfectly calibrated diving machines that plunge kilometres (miles) below the surface for hours at a stretch, foraging for food in the inky depths.

The heart rate slows, blood flow is restricted, oxygen is conserved.

So how could the ocean’s most accomplished deep-sea diver wind up with nitrogen bubbles poisoning its veins, like a scuba novice rising too quickly to the surface?

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Short answer: beaked whales — especially one species known as Cuvier’s — get really, really scared.

 AFP /Factfile on Cuvier’s beaked whale, repeatedly stranded in the Mediterranean because of man-made sonar, according to a new theory

“In the presence of sonar they are stressed and swim vigorously away from the sound source, changing their diving pattern,” lead author Yara Bernaldo de Quiros, a researcher at the Institute of Animal Health at the University of Las Palmas de Gran Canaria, Spain, told AFP.

“The stress response, in other words, overrides the diving response, which makes the animals accumulate nitrogen,” she added. “It’s like an adrenalin shot.”

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One type of sonar in particular throws these whales off balance.

– ‘Atypical’ mass strandings –

Developed in the 1950s to detect submarines, mid-frequency active sonar (MFAS) is used today in naval patrols and exercises, especially by the United States and its NATO allies.

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Starting around 1960, ships began emitting underwater signals in a range of about 5 kilohertz (kHz).

That is when the mass beaching of beaked whales, especially in the Mediterranean, began.

Between 1960 and 2004, 121 of these so-called “atypical” mass strandings took place, with at least 40 closely linked in time and place with naval activities.

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Fuerteventura Government/AFP/File / Handout Starting around 1960, ships began emitting underwater signals in a range of about 5 kilohertz (kHz) which is when the mass beaching of beaked whales began

These were not individual strandings of old or sick animals, nor en masse strandings such the one last November in New Zealand, when more than 200 pilot whales beached themselves together.

Rather, a handful or more beaked whales would wash ashore within a day or two, and no more than few dozen kilometres apart.

The most deadly episode, in 2002, saw 14 stranded over a 36-hour period in the Canary Islands during a NATO naval exercise.

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“Within a few hours of the sonar being deployed, the animals started showing up on the beach,” Bernaldo de Quiros said.

Outwardly, the whales showed no signs of disease or damage: they had normal body weight, and no skin lesions or infections.

Internally, it was another story. Nitrogen gas bubbles filled the veins, and their brains were ravaged by haemorrhaging.

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Autopsies also revealed damage to other organs, as well as to the spinal cord and central nervous system.

– Canary Island moratorium –

As with altitude sickness, reactions — in humans, and probably in whales — to nitrogen bubbles in the blood vary in type and intensity.

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A 2003 study in Nature on the possible link between sonar and whale deaths led to Spain banning such naval exercises around the Canary Islands in 2004.

“Up until then, the Canaries were a hotspot for this kind of ‘atypical’ strandings,” said Bernaldo de Quiros. “Since the moratorium, none have occurred.”

The authors called for similar bans to be extended to other regions where at-risk whales are known to congregate.

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The Cuvier’s grows up to seven metres (23 feet) and dines mainly on deep-water squid and fish. Its upwardly turned mouth gives the impression of a permanent smile.

The whale is listed as “vulnerable” on the IUCN Red List of endangered species, and is thought to have a global population of 5,000 to 7,000.

Other threats include ship strikes, ocean pollution and shifting habitats caused by climate change.


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Democrat who lived under a dictatorship explains why she believes it is time to impeach Trump

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One of the Democrats on the House Judiciary Committee who will be interviewing special counsel Robert Mueller on Wednesday explained to MSNBC's Lawrence O'Donnell why she believes it is time to initiate impeachment proceedings against President Donald Trump.

Rep. Debbie Mucarsel-Powell (D-FL) immigrated to the United States from Ecuador as a child. When Mucarsel-Powell was sworn-in to office following the 2018 midterm elections, she became the first Ecuadorian-American and first South American immigrant member of Congress.

"Most Americans don't have time to read a 448-page report," Mucarsel-Powell said. "We found substantial evidence that shows us that the president obstructed justice. "And I think it is critical for the American public to understand that and that’s why this hearing will be very important on Wednesday."

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Watch Rachel Maddow broadcast ‘exclusive story’ that undermines Mike Pence’s claims

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MSNBC anchor Rachel Maddow on Monday presented an "exclusive story" -- that undermines public claims by the Trump administration.

Vice President Mike Pence has been among the biggest defenders of the detention camps the administration is running near the southern border.

Pence has described the treatment of detainees as "compassionate" and "excellent."

https://twitter.com/VP/status/1149879335454515200

But that was not what Maddow reported on Monday.

"You haven’t seen this anywhere else," she introduced. "This is the first time this has been broadcast."

The story was an exclusive interview NBC News correspondent Julia Ainsley conducted with a child refugee from Guatemala who was held in one of the camps for eleven days.

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WATCH: 10 videos show massive flooding hitting Brooklyn and New Jersey after torrential downpour

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A massive flood is once again striking parts of New York City and New Jersey Monday as the heatwave gave way to a torrential downpour.

The storm moved through after 6 p.m. EST, dropping several inches of rain in a short period and causing immense flash flooding during rush hour. Commuters reported unusually large crowds on subway platforms, water flowing down subway stairs and huge leaks in the ceilings.

Airports were also dealing with the storm blowing through with time delays at LaGuardia, JFK and the Newark Airports.

Some folks took the flood in stride, bringing out pool toys to ride the waves:

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