Hexbyte  Hacker News  Computers Mysterious great white shark lair discovered in Pacific Ocean

Hexbyte Hacker News Computers Mysterious great white shark lair discovered in Pacific Ocean

Hexbyte Hacker News Computers

  • Hexbyte  Hacker News  Computers Salvador Jorgensen, a research scientist with the Monterey Bay Aquarium, tags a shark near the Farallon Islands. Photo: Courtesy Salvador Jorgensen

    Salvador Jorgensen, a research scientist with the Monterey Bay Aquarium, tags a shark near the Farallon Islands.

    Salvador Jorgensen, a research scientist with the Monterey Bay Aquarium, tags a shark near the Farallon Islands.

    Photo: Courtesy Salvador Jorgensen

  • Hexbyte  Hacker News  Computers Salvador Jorgensen, a research scientist with the Monterey Bay Aquarium, tags a shark off the coast of California. Photo: Courtesy Salvador Jorgensen

    Salvador Jorgensen, a research scientist with the Monterey Bay Aquarium, tags a shark off the coast of California.

    Salvador Jorgensen, a research scientist with the Monterey Bay Aquarium, tags a shark off the coast of California.

    Photo: Courtesy Salvador Jorgensen

  • Hexbyte  Hacker News  Computers A great white shark swims near the Farallon Islands. Scientists have discovered that the fish migrate in winter to a region in the Pacific Ocean that’s been dubbed the White Shark Cafe. Photo: Reinhard Dirscherl / Ullstein Bild

    A great white shark swims near the Farallon Islands. Scientists have discovered that the fish migrate in winter to a region in the Pacific Ocean that’s been dubbed the White Shark Cafe.

    A great white shark swims near the Farallon Islands. Scientists have discovered that the fish migrate in winter to a region in the Pacific Ocean that’s been dubbed the White Shark Cafe.

    Photo: Reinhard Dirscherl / Ullstein Bild

  • Hexbyte  Hacker News  Computers

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  • Hexbyte  Hacker News  Computers An 8-week-old kitten was rescued in December 2015. The cat, nicknamed Smurf for his dark violet hue, was colored by an undiluted garment dye intended for clothing. The dye masked abrasions and deep bite marks.

    An 8-week-old kitten was rescued in December 2015. The cat, nicknamed

    Smurf for his dark violet hue

    , was colored by an undiluted garment dye intended for clothing. The dye masked abrasions and deep bite marks.

    An 8-week-old kitten was rescued in December 2015. The cat, nicknamed

    Smurf for his dark violet hue

    , was colored by an undiluted garment dye intended for clothing. The dye masked abrasions and deep bite marks.

  • Hexbyte  Hacker News  Computers A turkey crosses through SFO security on  Feb. 1, 2016. Photo: Contributed Photo
  • Hexbyte  Hacker News  Computers On May 18, 2004, a young deer was spotted on the northwest side of the Golden Gate Bridge along the south approach to the span. Motorists traveling south began informing toll collectors. Patrols were not able to reach the deer to divert it away from the roadway before it proceeded into the southbound lanes. Traffic was immediately halted in both directions. The deer safely exited the roadway into Presidio property before reaching the MacArthur Tunnel.

    On May 18, 2004, a young

    deer was spotted on the northwest

    side of the Golden Gate Bridge along the south approach to the span. Motorists traveling south began informing toll collectors. Patrols were not able to reach the deer to divert it away from the roadway before it proceeded into the southbound lanes. Traffic was immediately halted in both directions. The deer safely exited the roadway into Presidio property before reaching the MacArthur Tunnel.

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    On May 18, 2004, a young

    deer was spotted on the northwest

    side of the Golden Gate Bridge along the south approach to the span. Motorists traveling south began informing toll collectors. Patrols were not able

    … more

  • Hexbyte  Hacker News  Computers On May 13, 2014, a cat saved a young boy's life when he was attacked by his neighbor's dog in Bakersfield. Photo: YouTube

    On May 13, 2014, a cat saved a young boy’s life when he was attacked by his neighbor’s dog in Bakersfield.

    On May 13, 2014, a cat saved a young boy’s life when he was attacked by his neighbor’s dog in Bakersfield.

    Photo: YouTube


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  • Hexbyte  Hacker News  Computers In Oct. 15, 1985, a humpback whale named Humphrey swam into San Francisco Bay and then ended up in the delta near Rio Vista. He was safely rescued, but needed to be rescued a second time in 1990. Photo: Steve Ringman, The Chronicle

    In Oct. 15, 1985, a humpback whale named Humphrey swam into San Francisco Bay and then ended up in the delta near Rio Vista. He was safely rescued, but needed to be

    rescued a second time in 1990

    .

    In Oct. 15, 1985, a humpback whale named Humphrey swam into San Francisco Bay and then ended up in the delta near Rio Vista. He was safely rescued, but needed to be

    rescued a second time in 1990

    .

    Photo: Steve Ringman, The Chronicle

  • Hexbyte  Hacker News  Computers Members of the Marine Mammal Center and the California Highway Patrol attempt to capture an elephant seal after it tried to cross Highway 37 in Sonoma County on Dec. 28, 2015. Photo: Chris Preovolos / (c) 2015

    Members of the Marine Mammal Center and the California Highway Patrol attempt to capture an elephant seal after it tried to

    cross Highway 37

    in Sonoma County on Dec. 28, 2015.

    Members of the Marine Mammal Center and the California Highway Patrol attempt to capture an elephant seal after it tried to

    cross Highway 37

    in Sonoma County on Dec. 28, 2015.

    Photo: Chris Preovolos

  • Hexbyte  Hacker News  Computers An alligator found in Alameda Creek near Fremont was deemed a public danger, then shot and killed on August 16th, 2016.  Photo: Courtesy California Dept. Of Fish And Wildlife

    An alligator found in Alameda Creek near Fremont was deemed a public danger, then shot and killed on August 16th, 2016. 

    An alligator found in Alameda Creek near Fremont was deemed a public danger, then shot and killed on August 16th, 2016. 

    Photo: Courtesy California Dept. Of Fish And Wildlife

  • Hexbyte  Hacker News  Computers On Aug. 29, 2005, a female ostrich somehow got out of a minivan heading north on the Golden Gate Bridge at the southern end of the bridge. A second ostrich did not get out. The driver got of the minivan to retrieve the bird as it headed south toward the toll plaza. The minivan was driven off the bridge by the passenger after the owner got out. Photo: A. Ko,  Golden Gate Bridge District

    On Aug. 29, 2005, a female ostrich somehow got out of a minivan heading

    north on the Golden Gate Bridge

    at the southern end of the bridge. A second ostrich did not get out. The driver got of the minivan to retrieve the bird as it headed south toward the toll plaza. The minivan was driven off the bridge by the passenger after the owner got out.

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    On Aug. 29, 2005, a female ostrich somehow got out of a minivan heading

    north on the Golden Gate Bridge

    at the southern end of the bridge. A second ostrich did not get out. The driver got of the minivan to

    … more

    Photo: A. Ko, Golden Gate Bridge District


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  • Hexbyte  Hacker News  Computers You get used to seeing strange things when you live in San Francisco, but every now and then you really have to do a double take. A man brought his pet goat onto Muni on July 6, 2016. Photo: Chris Preovolos

    You get used to seeing strange things when you live in San Francisco, but every now and then you really have to do a double take. A man brought his pet goat onto Muni on July 6, 2016.

    You get used to seeing strange things when you live in San Francisco, but every now and then you really have to do a double take. A man brought his pet goat onto Muni on July 6, 2016.

    Photo: Chris Preovolos

  • Hexbyte  Hacker News  Computers In May of 2014 this Chihuahua was rescued off of the center median of I-680 in Walnut Creek. The dog was eventually reunited with its family.  Photo: CHP Contra Costa

    In May of 2014 this Chihuahua was rescued off of the center median of I-680 in Walnut Creek. The dog was eventually reunited with its family. 

    In May of 2014 this Chihuahua was rescued off of the center median of I-680 in Walnut Creek. The dog was eventually reunited with its family. 

    Photo: CHP Contra Costa

  • Hexbyte  Hacker News  Computers Two whales nicknamed

    Two whales nicknamed “Delta” and “Dawn” swim past Fish and Game officials monitoring their condition. Marine biologists attempted to coax two wayward humpback

    whales back toward the Pacific Ocean

    using a fireboat from the Vallejo Fire Department in Rio Vista, Calif. on May 25, 2007. The whales initially responded to the spray from the boat, but, fearing they may get used to the activity, the operation was suspended after about an hour.

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    Photo: PAUL CHINN

  • Hexbyte  Hacker News  Computers Spock, a 27-pound Maine Coon cat, catches a nap with his friend Fluff Ball. Strangers would frequently mistake the cat for a wild animal and alert Spock's owner. Photo: Colleen Pizarev

    Spock, 

    a 27-pound Maine Coon cat

    , catches a nap with his friend Fluff Ball. Strangers would frequently mistake the cat for a wild animal and alert Spock’s owner.

    Spock, 

    a 27-pound Maine Coon cat

    , catches a nap with his friend Fluff Ball. Strangers would frequently mistake the cat for a wild animal and alert Spock’s owner.

    Photo: Colleen Pizarev


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  • Hexbyte  Hacker News  Computers File photo of two baby swans on May 19, 2014, in San Francisco. Shortly after the birth of two baby swans, the pair mysteriously disappeared. The baby swans were born to the couple who live at the lake surrounding the Palace of Fine Arts despite earlier efforts to lower the swan population. Photo: Brant Ward, The Chronicle

    File photo of two baby swans on May 19, 2014, in San Francisco. Shortly after the birth of two baby swans, 

    the pair mysteriously disappeared

    . The baby swans were born to the couple who live at the lake surrounding the Palace of Fine Arts despite earlier efforts to lower the swan population.

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    File photo of two baby swans on May 19, 2014, in San Francisco. Shortly after the birth of two baby swans, 

    the pair mysteriously disappeared

    . The baby swans were born to the couple who live at the lake

    … more

    Photo: Brant Ward, The Chronicle

  • Hexbyte  Hacker News  Computers A chicken walking through traffic slowed down the morning commute just before the Bay Bridge toll plaza on Sept. 2, 2015. Photo: @nicjonestweets
  • Hexbyte  Hacker News  Computers After a female dog named Cora was surrendered by her owner to the Marin Humane Society on March 5, 2016, she was later reunited by her liter of four pups -- all named after

    After a female dog named Cora was surrendered by her owner to the Marin Humane Society on March 5, 2016, she was later

    reunited by her liter

    of four pups — all named after “Downton Abbey” characters.

    After a female dog named Cora was surrendered by her owner to the Marin Humane Society on March 5, 2016, she was later

    reunited by her liter

    of four pups — all named after “Downton Abbey” characters.

    Photo: Marin Humane Society

  • Hexbyte  Hacker News  Computers CHP officers follow a flock of geese westbound Interstate 80 on May 22, 2016. Photo: Facebook Screenshot / CHP

    Photo: Facebook Screenshot / CHP


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  • Hexbyte  Hacker News  Computers California Highway Patrol officials are working to reunite a small black chihuahua-mix with its owners after officers chased the animal on the Bay Bridge on April 3, 2016.
  • Hexbyte  Hacker News  Computers On March 24, 2016, a northern fur seal pup was rescued after it apparently lost its way, tried to cross a street in Fremont and eventually waddled into the front yard of a home. Photo: Fremont Police Department

    On March 24, 2016, a northern fur

    seal pup was rescued

    after it apparently lost its way, tried to cross a street in Fremont and eventually waddled into the front yard of a home.

    On March 24, 2016, a northern fur

    seal pup was rescued

    after it apparently lost its way, tried to cross a street in Fremont and eventually waddled into the front yard of a home.

    Photo: Fremont Police Department

  • Hexbyte  Hacker News  Computers A northern fur seal pup nicknamed Pipester turned up at the front door of a Hayward ironworks shop on Jan. 20, 2016. Photo: Matthew Van Valkenburg

    A northern fur seal

    pup nicknamed Pipester

    turned up at the front door of a Hayward ironworks shop on Jan. 20, 2016.

    A northern fur seal

    pup nicknamed Pipester

    turned up at the front door of a Hayward ironworks shop on Jan. 20, 2016.

    Photo: Matthew Van Valkenburg

  • Hexbyte  Hacker News  Computers Animal keeper Amy Corso plays with infant gorilla Kabibe at the San Francisco Zoo gorilla preserve on Oct. 3, 2013. Kabibe died in a tragic accident when she was crushed by a door in her enclosure in November 2015. The San Francisco Zoo was fined $1,750 for her death by the U.S. Department of Agriculture. Photo: May Woon

    Animal keeper Amy Corso plays with infant gorilla Kabibe at the San Francisco Zoo gorilla preserve on Oct. 3, 2013. Kabibe died in a

    tragic accident

    when she was crushed by a door in her enclosure in November 2015. The San Francisco Zoo was fined $1,750 for her death by the U.S. Department of Agriculture.

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    Animal keeper Amy Corso plays with infant gorilla Kabibe at the San Francisco Zoo gorilla preserve on Oct. 3, 2013. Kabibe died in a

    tragic accident

    when she was crushed by a door in her enclosure in November

    … more

    Photo: May Woon


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  • Hexbyte  Hacker News  Computers A group of raccoons attacked a couple and their two small dogs in the Richmond District on Nov. 1, 2015. The woman received a rabies shot and the dogs sustained minor injuries. Photo: WildCare
  • Hexbyte  Hacker News  Computers A great white shark was spotted devouring a seal near Alcatraz in October 2015.   Pictured: In this file photo, a surfer looks back to shore as a shark, possibly a great white, swims by off the California Coast.  Photo: KEVIN SULLIVAN, AP / THE ORANGE COUNTY REGISTER
    Pictured: In this file photo, a surfer looks back to shore as a shark, possibly a great white, swims by off the California Coast.  less

    Pictured: In this file photo, a surfer looks back to shore as a shark, possibly a great white, swims by off the California … more

    Photo: KEVIN SULLIVAN, AP

  • Hexbyte  Hacker News  Computers A wild pig weighing about 300 pounds wanders through Pescadero Park near La Honda. In October 2013, wild pigs were wreaking havoc on Almaden Valley in San Jose. Photo: DEANNE FITZMAURICE

    A wild pig weighing about 300 pounds wanders through Pescadero Park near La Honda. In October 2013, 

    wild pigs were wreaking havoc

    on Almaden Valley in San Jose.

    A wild pig weighing about 300 pounds wanders through Pescadero Park near La Honda. In October 2013, 

    wild pigs were wreaking havoc

    on Almaden Valley in San Jose.

    Photo: DEANNE FITZMAURICE

  • Hexbyte  Hacker News  Computers UC Davis trained pigeons to categorize digitized slides and mammograms of benign and malignant human breast tissue. Photo: U.C. Davis

    UC Davis

    trained pigeons

    to categorize digitized slides and mammograms of benign and malignant human breast tissue.

    UC Davis

    trained pigeons

    to categorize digitized slides and mammograms of benign and malignant human breast tissue.

    Photo: U.C. Davis


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  • Hexbyte  Hacker News  Computers Kevin Hines sits on the rocks next to Fort Point underneath  the Golden Gate Bridge in 2000 when he was 19 years old. He survived jumping off of the bridge in a suicide attempt when he was saved by a sea lion that was circling beneath him. Photo: John Storey, SFC

    Kevin Hines sits on the rocks next to Fort Point underneath the Golden Gate Bridge in 2000 when he was 19 years old. He survived jumping off of the bridge in a suicide attempt when he was saved by a

    sea lion that was circling beneath him

    .

    less

    Kevin Hines sits on the rocks next to Fort Point underneath the Golden Gate Bridge in 2000 when he was 19 years old. He survived jumping off of the bridge in a suicide attempt when he was saved by a

    sea lion … more

    Photo: John Storey, SFC


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Photo: Courtesy Salvador Jorgensen

Salvador Jorgensen, a research scientist with the Monterey Bay Aquarium, tags a shark near the Farallon Islands.

Salvador Jorgensen, a research scientist with the Monterey Bay Aquarium, tags a shark near the Farallon Islands.

Photo: Courtesy Salvador Jorgensen

A scientific mission into the secret ocean lair of California’s great white sharks has provided tantalizing clues into a vexing mystery — why the fearsome predators spend winter and spring in what has long appeared to be an empty void in the deep sea.

A boatload of researchers from five scientific institutions visited the middle-of-nowhere spot between Baja California and Hawaii this past spring on a quest to learn more about what draws the big sharks to what has become known as the White Shark Cafe, almost as if they were pulled by some astrological stimulus.

The sharks’ annual pilgrimage to the mid-Pacific region from the coasts of California and Mexico has baffled scientists for years, not just because it is so far away — it takes a month for the sharks to get there — but because it seemed, on the surface, to be lacking the kind of prey or habitat that the toothy carnivores prefer.

But the researchers made a remarkable discovery. Instead of blank, barren sea, the expedition, led by scientists with Stanford University and the Monterey Bay Aquarium, found a vast community of tiny light-sensitive creatures so tantalizing that the sharks cross the sea en masse to reach them.

The primary lure, scientists believe, is an extraordinary abundance of squid and small fish that migrate up and down in a little understood deep-water portion of ocean known as the “mid-water,” a region skirting the edge of complete darkness that could provide an immeasurably valuable trove of information about the ocean ecosystem and climate change.

“The story of the white shark tells you that this area is vitally important in ways we never knew about,” said Salvador Jorgensen, a research scientist for the Monterey Bay Aquarium and one of the expedition’s leaders. “They are telling us this incredible story about the mid-water, and there is this whole secret life that we need to know about.”

The researchers’ focus, a 160-mile-radius subtropical region about 1,200 nautical miles east of Hawaii, was essentially unknown to science until marine scientist Barbara Block, of Stanford University’s Hopkins Marine Station, began attaching acoustic pinger tags to white sharks 14 years ago.

Block discovered that the local sharks, known as northeastern Pacific whites, feed on elephant seals and other marine mammals in the so-called Red Triangle, between Monterey Bay, the Farallon Islands and Bodega Head, from about August to December. She also tracked their movements into San Francisco Bay and around Guadalupe Island, in Mexico.

Hexbyte  Hacker News  Computers

But then, each December, the acoustic tags showed a mass movement out to sea that was as confusing to the researchers as it was surprising.

Block found that the sharks were leaving the food-rich waters along the West Coast to spend spring and most of the summer in a patch of open ocean about the size of Colorado, a place that looked in satellite images like an empty, oceanic Sahara desert.

She named it the White Shark Cafe even though she wasn’t sure whether the sharks went there for food or sex.

To find out, Block organized the monthlong expedition in April and May aboard the Schmidt Ocean Institute’s research vessel Falkor, which was equipped with high-tech instruments, sail drones and a remotely operated submarine. Last fall, before departure, her team of scientists tracked down 36 local sharks using acoustic signals and fitted them with high-tech satellite monitoring tags with locator beacons programmed to pop off and float to the surface during the cafe expedition.

The scheme worked. The researchers got data from 10 of the 22 tags that floated up and signaled the Falkor that they had detached and were bobbing around ready to be collected, an exercise that Jorgensen called “a white shark treasure hunt.” The scientists also obtained recorded information on shark movements and behavior over the previous months from six other great whites through radio uplinks. The rest only transmitted their location or were not recovered.

The data on the recovered tags documented highly unusual diving behavior at depths scientists had rarely before seen in white sharks.

Hexbyte Hacker News Computers Know your great white sharks

Great white sharks, known scientifically as Carcharodon carcharias, are protected under state legislation that makes it illegal to fish for them. The trade in shark parts — mainly jaws and fins — is also illegal internationally under the Convention on International Trade in Endangered Species.

They average 15 to 16 feet in length, but can grow much larger. The biggest white shark ever recorded was caught in 1939 and it was 21 feet long and weighed 7,300 pounds.

Starting in late summer and fall, an estimated 220 white sharks feed offshore of the Farallon Islands, Año Nuevo and Drakes Bay, but at least 20 have been documented over the years inside San Francisco Bay, including one seen devouring a seal in 2015 just a few feet off Alcatraz Island.

Female sharks typically visit the Gulf of the Farallones in alternate years, suggesting that their migration pattern is tied to a two-year reproductive cycle.

DNA testing has shown the sharks off the coast of California are genetically unique compared with other great whites.

Researchers tagged 37 great white sharks last year and have given them names including Torpedo, Scargirl, Sicklefin, OrcaFin and ShawShark Redemption. The oldest and longest studied shark is a 16-foot, 3,158-pound great white named Tom Johnson, which was first seen off the Farallon Islands in 1987.

The only reported fatal human-shark encounter off San Francisco shores occurred in May 1959, when 18-year-old Albert Kogler Jr. died after he was attacked in roughly 15 feet of water while swimming off Baker Beach.

Eleven people have been killed by sharks off the California coast since the first documented attack on a human in Pacific Grove in December, 1952. The body of a probable 12th victim was never found, so he isn’t counted.

Sources: Stanford University’s Hopkins Marine Station; Monterey Bay Aquarium; Schmidt Ocean Institute; National Oceanic and Atmospheric Administration.

On the way to the cafe, the sharks made periodic dives 3,000 feet deep, a surprising discovery given that the big fish normally wouldn’t be able to stay warm enough to digest food in such cold, pressurized depths. The sharks, researchers found, were using warm circular currents to get down the water column, suggesting they were following prey. Still, it isn’t clear what they were eating.

Once they reached their destination in late winter and early spring, the animals engaged in “bounce dives” down to 1,400 feet below the surface during the day and 650 feet at night, Jorgensen said.

In April, the male sharks started behaving very differently from the females, moving individually up and down the water in a V-shape as many as 140 times a day, Jorgensen said. The females, on the other hand, continued their previous behavior, diving deep during the day and shallow at night, he said.

The scientists still haven’t figured out the disparate gender behaviors.

“Either they are eating something different or this is related in some way to their mating,” Jorgensen said.

What’s clear so far is that, like the hidden community of specialized wildlife in the Sahara, the shark cafe is a swirling mass of tiny phytoplankton, fish, squid and jellies. They move up and down in a soupy layer deep under water, a kind of twilight zone just below where sunlight stops penetrating the ocean depths.

“It’s the largest migration of animals on Earth — a vertical migration that’s timed with the light cycle,” Jorgensen said. “During the day they go just below where there is light and at night they come up nearer the surface to warmer, more productive waters under the cover of darkness.”

It’s a surreal deep water world populated by bioluminescent lantern fish and other species that have evolved amazing adaptations to darkness, Jorgensen said.

Scientists in recent years have discovered hundreds of new species in deep water zones like this one. The uniquely abundant mass of fish draws all kinds of predators, like small cookiecutter sharks, which have evolved light-emitting organs called photophores on the underside of their bodies that act, to prey, like invisibility cloaks.

The white sharks aren’t the only large predators tracking the mid-water creatures. Squid-eating bigeye tuna, blue and mako sharks also frequent the cafe. Jorgensen said these larger fish may be what the white sharks eat, but there isn’t any definitive evidence of that.

“What we’ve learned through the progression of our research is that this mid-water layer is extremely important for white sharks,” he said. “They are swimming in these layers, tracking (prey) day and night. … It’s a game of hide-and-seek.”

Scientists say this little understood mid-water zone is a biological laboratory that, with more research, could lead to biomedical breakthroughs and yield clues to how the ocean absorbs carbon dioxide and how species adapt to climate change. There is also concern that it is ripe for exploitation, particularly long-line and drift net fishing.

Triggered by some crypic mechanism, the sharks leave their mid-ocean sanctum during the summer and begin to gather along the coast of California around August.

Block said researchers will not know whether the sharks were feeding, mating or doing both during their time in the White Shark Cafe until the analyses are completed.

“We now have a gold mine of data. We have doubled the current 20-year data set on white shark diving behaviors and environmental preferences in just three weeks,” Block said. This “will help us better understand the persistence of this unique environment and why it attracts such large predators.”

Peter Fimrite is a San Francisco Chronicle staff writer. Email: pfimrite@sfchronicle.com. Twitter: @pfimrite