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A mysterious den of great white sharks has been discovered in what experts once thought to be a "virgin and barren" stretch of the Pacific Ocean.
The surprising discovery shocked scientists, who did not know that the area was home to sharks – and assumed that the region could not support their diet.
Each year, California's large white shark community makes a mysterious pilgrimage to a region dubbed the "White Shark Coffee".
Deadly sea creatures swim for months to spend the winter and spring in a remote area of the Pacific Ocean.
The area between Baja California and Hawaii has been a major mystery for scientists.
But now researchers have followed the sharks and visited the "middle of nowhere," as reported for the first time in the San Francisco Chronicle.
Especially confused scientists were the reasons why sharks swam over great distances.
This seemed particularly strange, since it was supposed that the region lacked the type of prey that the great whites preferred.
But a joint expedition from Stanford University and the Monterey Bay Aquarium revealed that the shark lair had plenty of food to get around.
Researchers have discovered a "large community" of tiny, light-sensitive creatures that are very tempting for Pacific sharks.
According to experts, the region is full of squids and small fish that move in a deep water area called "intermediate waters".
It is the region just above the deepest areas of the sea, where the darkness is total.
The researchers are now hoping to study the region further.
"The white shark story tells you that this area is of vital importance for unknown reasons," said Salvador Jorgensen, a researcher at the Monterey Bay Aquarium.
"They tell us this incredible story about water and there's all this secret life we need to know."
He added: "What we learned during our research is that this layer of water is extremely important for white sharks."
The researchers are focused on a large area of 160 miles radius that is about 1200 nautical miles east of Hawaii.
Scientists have only a very limited understanding of the area, because of its remote location.
14 years ago, scientist Barbara Block from Standford Marine Station was interested in the area.
Block found that between August and December, local sharks were feeding in the "red triangle", an area near Monterey Bay.
But in December, the acoustic labels would follow a huge movement towards the sea, leaving the experts perplexed.
It turned out that sharks were swimming to an ocean area twice as big as England – what Block has dubbed the "white shark coffee".
To study the issue, block acoustic tags attached to 36 local sharks, as well as satellite surveillance beacons with location tags designed to appear and float to the surface.
Then, researchers organized a one – month expedition on the Falkor research vessel, with the aim of finding the beacons.
The researchers were able to obtain information on 10 of the 22 tags floating on the surface in what Block described as a "white shark treasure hunt".
"We now have a wealth of data. We have doubled the current 20-year database of white shark diving behaviors and environmental preferences in just three weeks, "Block said.
She added that this "would help us better understand the persistence of this unique environment and why it attracts large predators".
It turned out that sharks were performing dives of an exceptional depth of 3,000 feet, using warm currents to track their prey to the bottom of the water.
Scientists believe, but can not say for sure, that sharks nibble small fish and squid.
Experts say that sharks of different sexes also behaved differently.
Male sharks dive in V-shaped water, up to 140 times a day.
Females, meanwhile, would dive deep into the day and shallow in the light – creating additional confusion for scientists.
"This is the largest migration of animals on Earth – a vertical migration synchronized with the cycle of light," said Jorgensen.
"During the day, they pass just under the light and at night they come closer to the surface to warmer, more productive water under the cover of darkness."
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