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| MARIANA TRENCH ANIMAL |
Listen to the mysterious 'alien song' heard deep in the Mariana trench: Researchers reveal unexplained sound heard 36,000 feet down - That is 10,058 meters, or 10 kilometers, or 6.25 miles deep.
- The Mariana Trench is the deepest place in the world's oceans
- Scientists sent a hydrophone down to Challenger Deep, the deepest part
- Strange booming is unidentified - but it could be an animal call
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| MARIANA TRENCH ANIMALS |
Researchers have released audio of a strange booming sound heard in the the deepest part of the ocean. Scientists at OSU's Hatfield Marine Science Center named it the 'Western Pacific Biotwang' and say their best guess is that it is a new type of previously unheard whale call.
Lasting between 2.5 and 3.5 seconds, the five-part call includes deep moans at frequencies as low as 38 hertz and a metallic finale that pushes as high as 8,000 hertz.
'It's very distinct, with all these crazy parts,' said Sharon Nieukirk, senior faculty research assistant in marine bioacoustics at Oregon State. 'The low-frequency moaning part is typical of baleen whales, and it's that kind of twangy sound that makes it really unique. We don't find many new baleen whale calls.'
Continue reading, WATCH VIDEO with the mysterious sound, other videos about life forms in the Mariana trench, and see explanatory illustrations
'We need to determine how often the call occurs in summer versus winter, and how widely this call is really distributed.'
VIDEO: Amazing discovery: Deepest ever fish found Sea ghost breaks record for deepest living fish
VIDEO: BIZARRE CREATURES INHABITING THE MARIANA TRENCH
VIDEO - Biotwang” mysterious sound in the Mariana Trench
Recorded via passive acoustic ocean gliders, which are instruments that can travel autonomously for months at a time and dive up to 1,000 meters, the Western Pacific Biotwang most closely resembles the so-called 'Star Wars' sound produced by dwarf minke whales on the Great Barrier Reef off the northeast coast of Australia, researchers say.
The Mariana Trench, the deepest known part of the Earth's oceans, lies between Japan to the north and Australia to the south and features depths in excess of 36,000 feet.
Minke whales are baleen whales – meaning they feed by using baleen plates in their mouths to filter krill and small fish from seawater – and live in most oceans.
The sound could be from a baleen whale in a romantic mood
Nieukirk said the Western Pacific Biotwang has enough similarities to the Star Wars call – complex structure, frequency sweep and metallic conclusion – that it's reasonable to think a minke whale is responsible for it. But scientists can't yet be sure, and many other questions remain.
They produce a collection of regionally specific calls, which in addition to the Star Wars call include 'boings' in the North Pacific and low-frequency pulse trains in the Atlantic.
'We don't really know that much about minke whale distribution at low latitudes,' said Nieukirk, lead author on the study whose results were recently published in the Journal of the Acoustical Society of America.
For example, baleen whale calls are often related to mating and heard mainly during the winter, yet the Western Pacific Biotwang was recorded throughout the year.
'If it's a mating call, why are we getting it year round? That's a mystery,' said Nieukirk, part of the team at the Cooperative Institute for Marine Resources Studies, a partnership between OSU and the NOAA Pacific Marine Environmental Laboratory.
'If it's a mating call, why are we getting it year round? That's a mystery,' said Nieukirk, part of the team at the Cooperative Institute for Marine Resources Studies, a partnership between OSU and the NOAA Pacific Marine Environmental Laboratory.
'We need to determine how often the call occurs in summer versus winter, and how widely this call is really distributed.'
THE WORLD'S DEEPEST TRENCH
- The Mariana Trench is the deepest part of the world's oceans located in the western Pacific Ocean, to the east of the Mariana Islands.
- The trench is 1,580 miles (2,550 km) long but has an average width of only 43 miles (69 km).
- The Mariana Trench is the deepest part of the world's oceans. It is located in the western Pacific Ocean, to the east of the Mariana Islands. The trench is about 1,580 miles (2,550 km) long but has an average width of just 43 miles (69 km)
- The distance between the surface of the ocean and the trench's deepest point, the Challenger Deep is nearly 7 miles (11 km).
- Director James Cameron became the first solo diver to reach the bottom of Challenger Deep in 2012.
'Now that we've published these data, we hope researchers can identify this call in past and future data, and ultimately we should be able to pin down the source of the sound,' Nieukirk said.
'More data are needed, including genetic, acoustic and visual identification of the source, to confirm the species and gain insight into how this sound is being used.
'Our hope is to mount an expedition to go out and do acoustic localization, find the animals, get biopsy samples and find out exactly what's making the sound. It really is an amazing, weird sound, and good science will explain it.'
'More data are needed, including genetic, acoustic and visual identification of the source, to confirm the species and gain insight into how this sound is being used.
'Our hope is to mount an expedition to go out and do acoustic localization, find the animals, get biopsy samples and find out exactly what's making the sound. It really is an amazing, weird sound, and good science will explain it.'
Researchers used a hydrophone that was placed seven miles (11.3km) down - further than the height of Everest - from the surface of the water - in a trough called Challenger Deep to eavesdrop in the depths
Last year scientists from the National Oceanic and Atmospheric Administration, Oregon State University and the US Coast Guard sent a device that spent three weeks eavesdropping at the bottom of the trench.
They captured the sounds of whales and dolphins passing by, a ship's propeller and even heard an earthquake that hit the region on 16 July last year.
'You would think that the deepest part of the ocean would be one of the quietest places on Earth,' said Robert Dziak, a NOAA research oceanographer and chief scientist on the project.
'Yet there really is almost constant noise from both natural and man-made sources.'
'The ambient sound field at Challenger Deep is dominated by the sound of earthquakes, both near and far was well as the distinct moans of baleen whales and the overwhelming clamor of a category 4 typhoon that just happened to pass overhead.
'There was also a lot of noise from ship traffic, identifiable by the clear sound pattern the ship propellers make when they pass by,' added Dziak.
'Guam is very close to Challenger Deep and is a regional hub for container shipping with China and The Philippines.'
They captured the sounds of whales and dolphins passing by, a ship's propeller and even heard an earthquake that hit the region on 16 July last year.
'You would think that the deepest part of the ocean would be one of the quietest places on Earth,' said Robert Dziak, a NOAA research oceanographer and chief scientist on the project.
'Yet there really is almost constant noise from both natural and man-made sources.'
'The ambient sound field at Challenger Deep is dominated by the sound of earthquakes, both near and far was well as the distinct moans of baleen whales and the overwhelming clamor of a category 4 typhoon that just happened to pass overhead.
'There was also a lot of noise from ship traffic, identifiable by the clear sound pattern the ship propellers make when they pass by,' added Dziak.
'Guam is very close to Challenger Deep and is a regional hub for container shipping with China and The Philippines.'
The trench's deepest point, Challenger Deep (marked) is nearly 7 miles (11 km). It lies around 200 miles (322 km) southwest of the US territory of Guam
Getting it down there was tricky, the researchers explained and involved the hydrophone being placed in a titanium case and lowered to the depths of the ocean.
'We had never put a hydrophone deeper than a mile or so below the surface, so putting an instrument down some seven miles into the ocean was daunting,' said Haru Matsumoto, an Oregon State ocean engineer.
'We had to drop the hydrophone mooring down through the water column at no more than about five meters per second.
'Structures don't like rapid change and we were afraid we would crack the ceramic housing outside the hydrophone.'
The hydrophone is akin to sending a deep-space probe to the outer solar system,' Dziak said. 'We're sending out a deep-ocean probe to the unknown reaches of inner space.'
'We had never put a hydrophone deeper than a mile or so below the surface, so putting an instrument down some seven miles into the ocean was daunting,' said Haru Matsumoto, an Oregon State ocean engineer.
'We had to drop the hydrophone mooring down through the water column at no more than about five meters per second.
'Structures don't like rapid change and we were afraid we would crack the ceramic housing outside the hydrophone.'
The hydrophone is akin to sending a deep-space probe to the outer solar system,' Dziak said. 'We're sending out a deep-ocean probe to the unknown reaches of inner space.'
Graphic representation of the Mariana Trench and surrounding terrain. Scientists from the National Oceanic and Atmospheric Administration, Oregon State University and the US Coast Guard spent three weeks eavesdropping at the bottom of trench in the Pacific Ocean
At that depth the pressure is immense
- In an average person's home or office, the atmospheric pressure is about 14.7 pounds per square inch (101 kPa) but at the bottom of the Mariana Trench, it is more than 16,000 PSI (110,000 kPa).
- The project was designed to establish a baseline for ambient noise in the deepest part of the Pacific Ocean.
- Anthropogenic, or human-caused noise, has grown steadily over the past several decades and these recordings will allow scientists in the future to determine if the noise levels are increasing.
- For the past several months, Dziak and his colleagues have been analysing the sounds and trying to differentiate natural sounds from ships and other human activities.
The hydrophone was placed in a titanium case and lowered to the depths of the ocean. Getting it down there was tricky, the researchers said
'We recorded a loud magnitude 5.0 earthquake that took place at a depth of about 10 kilometers (or more than six miles) in the nearby ocean crust,' Dziak said.
'Since our hydrophone was at 11 kilometers, it actually was below the earthquake, which is really an unusual experience.
'The sound of the typhoon was also dramatic, although the cacophony from big storms tends to be spread out and elevates the overall noise for a period of days.'
Matsumoto said the hydrophone also picked up a lot of noise from the surface of the ocean - seven miles above - including waves and winds disturbing the surface.
'Sound doesn't get as weak as you think it does even that far from the source,' he said.
But sound only makes it to the bottom of Challenger Deep if the source of sound is directly above the Challenger Deep canyon because of the way the sound waves propagate through the water.
In December 2014 a new record was set for the deepest fish ever seen in the world, at an incredible depth of 26,722 feet (8,145 metres).
The snailfish was found at the bottom of the Mariana Trench, and broke the previous record by almost 1,640ft (500 metres).
'We need to determine how often the call occurs in summer versus winter, and how widely this call is really distributed. Now that we've published these data, we hope researchers can identify this call in past and future data, and ultimately we should be able to pin down the source of the sound,' Nieukirk said.
'Since our hydrophone was at 11 kilometers, it actually was below the earthquake, which is really an unusual experience.
'The sound of the typhoon was also dramatic, although the cacophony from big storms tends to be spread out and elevates the overall noise for a period of days.'
Matsumoto said the hydrophone also picked up a lot of noise from the surface of the ocean - seven miles above - including waves and winds disturbing the surface.
'Sound doesn't get as weak as you think it does even that far from the source,' he said.
But sound only makes it to the bottom of Challenger Deep if the source of sound is directly above the Challenger Deep canyon because of the way the sound waves propagate through the water.
In December 2014 a new record was set for the deepest fish ever seen in the world, at an incredible depth of 26,722 feet (8,145 metres).
The snailfish was found at the bottom of the Mariana Trench, and broke the previous record by almost 1,640ft (500 metres).
'We need to determine how often the call occurs in summer versus winter, and how widely this call is really distributed. Now that we've published these data, we hope researchers can identify this call in past and future data, and ultimately we should be able to pin down the source of the sound,' Nieukirk said.
'More data are needed, including genetic, acoustic and visual identification of the source, to confirm the species and gain insight into how this sound is being used.
'Our hope is to mount an expedition to go out and do acoustic localization, find the animals, get biopsy samples and find out exactly what's making the sound. It really is an amazing, weird sound, and good science will explain it.'
Last year scientists from the National Oceanic and Atmospheric Administration, Oregon State University and the US Coast Guard sent a device that spent three weeks eavesdropping at the bottom of the trench.
This shows three models of how sound should propagate from the ocean surface down the bottom of Challenger Deep. The red colour represents high sound energy. These maps show that sound only makes it to the bottom of Challenger Deep if the source of sound is directly above the Challenger Deep canyon
LIFE IN THE TRENCHES
- Ocean trenches are some of the most hostile habitats on earth.
- Pressure is more than 1,000 times that on the surface, and the water temperature is just above freezing.
- No sunlight penetrates the deepest ocean trenches, making photosynthesis impossible.
- Organisms that live in ocean trenches have evolved with unusual adaptations to thrive in these cold, dark canyons.
- In general, life in dark ocean trenches is isolated and slow-moving.
- In December 2014 a new record was set for the deepest fish ever seen in the world, at an incredible depth of 26,722ft (8,145 metres).
- The snailfish was found at the bottom of the Mariana Trench, and broke the previous record by almost 1,640ft (500 metres)
Source
VIDEO - Long Way Down:
Mariana Trench | National Geographic
this short video illustrates what's in the ocean as a probe descends all the way to 33,000 feet deep. Just minor animals there, such as snails and such.
VIDEO - Life in the Mariana Trench - The creatures you would meet at different depths as a probe descends.
VIDEO: Amazing discovery: Deepest ever fish found Sea ghost breaks record for deepest living fish
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