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Most dominant shark of the deep sea tagged at depth for the first time

Dean Grubbs thinks great white sharks are boring.   The veteran shark scientist, who has researched different shark species for 30 years, is vastly more intrigued by the little-seen dominant predator of the deep, dark, tropical and temperate oceans: the sixgill shark (most sharks have five gills). “These things are way cooler than any white…

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Most dominant shark of the deep sea tagged at depth for the first time

Dean Grubbs thinks great white sharks are boring.  

The veteran shark scientist, who has researched different shark species for 30 years, is vastly more intrigued by the little-seen dominant predator of the deep, dark, tropical and temperate oceans: the sixgill shark (most sharks have five gills).

“These things are way cooler than any white shark,” said Grubbs, an associate director of research at Florida State University’s Coastal and Marine Laboratory.

Sixgills are ancient beasts of the dark ocean, often inhabiting waters some 700 to 3,200 feet (200 to 1,000 meters) below the sea, whereas white sharks are a dominant species found near the surface, sometimes to beachgoers’ dismay. “[Sixgills] are the biggest, dominant predator of these depths,” Grubbs said. The sharks often grow to 16 feet in length, but can become even larger. 

And after multiple failed attempts at tagging a bluntnose sixgill shark with a GPS tracker deep under the water — to improve the understanding of how these elusive sharks live — Florida State University’s Grubbs along with a team of researchers from the Florida Museum of Natural History, the Cape Eleuthera Institute in the Bahamas, and deep sea explorers OceanX, have successfully tagged a sixgill shark in its natural habitat at some 1,730 feet below the surface. 

The late June 2019 mission in The Bahamas — funded by a collaboration of OceanX, the Moore Bahamas Foundation, and the Bloomberg Philanthropies’ Vibrant Oceans Initiative (collectively called “One Big Wave”) — can be seen in the video below, released Thursday morning.

While Grubbs was on deck of OceanX’s 184-foot exploration vessel the Alucia, shark scientist Gavin Naylor descended in a yellow submersible and found a safe spot to tag the sixgill. It was a fortunate shot. 

“It was the last dive on the last day,” said Brendan Talwar, a research associate at Cape Eleuthera Institute who helped build the shark tagging device. 

The 11-minute video is a quality introduction to both the mission and the elusive sharks, which have been roaming the seas since at least 185 million years ago, when dinosaurs dominated the planet. (“[Sixgills] haven’t changed in millions of years,” noted Talwar). Here are some highlights from the footage:

  • 5:50: a massive sixgill shark, perhaps 16 feet long (5 meters), visits the OceanX submersible

  • 7:15: Gaze into the cryptic green eye of a sixgill shark

  • 8:30: Naylor, ever coolly, tags a sixgill

Grubbs, though, has tagged dozens of sixgill sharks in the past. Just not in the sixgills’ deep realm. Instead, tagging sixgills has inevitably required catching the great creatures on a line and temporarily hauling the sharks up to an alien place — the surface world.  

Tagging a sixgill from a deep sea submersible is certainly trying and expensive, but it’s significantly better for the animal.

“We don’t have to expose sixgills to any trauma associated with bringing them to the surface,” said Grubbs, noting the warmth, light, hook, and out-of-water anguish the sharks experience. 

The GPS tag is designed to pop off the shark after three months, which means the tag should have floated to the surface and pinged a satellite about two weeks ago. The tag hasn’t yet pinged. But sometimes the tags can get caught in drifting vegetation, or it might take longer to ping for technical reasons. Talwar has been checking each morning (and often afternoons, as well as just before we spoke).

“They are tough.”

Previously, Grubbs’ tagging research proved that if a fishing vessel accidentally catches a sixgill and brings the animal to the surface, the sharks wouldn’t necessarily die, as was previously thought. Instead, the sharks can be returned to the water where they’ll likely swim back down to the dark depths, and survive. “They are tough,” said Grubbs.

They’re also eerie. Like many deep sea creatures, sixgills creep slowly through the water. In the OceanX footage, the sharks moved placidly around the submersible. That’s because food is scarce in the deeps, so moving slowly is a wise adaption to conserve energy, explained Grubbs.

“If you’re living at those deep, cold depths, everything is slow,” he said. 

And then there’s the sixgills’ jaw. They are profoundly flexible, allowing the sixgills’ serrated teeth and wide mouth to bend across large prey, like a whale, and start sawing through flesh. “They’ll carve out chunks,” said Grubbs. 

The cryptic green eye of a sixgill shark.

The cryptic green eye of a sixgill shark.

Image: oCEANX / ONE BIG WAVE

Launching the sub at night.

Launching the sub at night.

Image: OCEANX / ONE BIG WAVE

Previous tagging expeditions have already revealed compelling insight into the life of a sixgill. During the day, sixgills stay at colder depths of around 41 degrees Fahrenheit (5 Celsius). But at night, the sharks follow prey upwards, migrating to where temperatures hit around 60 F (16 C), said Grubbs.

That’s how Grubbs and company sleuthed out sixgill sharks on this recent mission. In the darkness, the researchers parked the submersible atop a slope and waited for the sharks to swim up. To attract the creatures’ interest, the scientists tied fish to a pole that extended out from the submarine. 

While there’s much to learn about sixgills, Talwar emphasized there’s still much to learn about all shark species, even some of the most ubiquitous sharks, like silky sharks. 

“We don’t even know enough to effectively manage the most commonly seen sharks that are caught at the surface,” said Talwar.

And there are some 500 species of sharks on the planet. 

But few are as little-known as the great beasts of the deep, the sixgills, who have sniffed out dead prey on the ocean floors since long before the T. rex even evolved.

“We still know almost nothing,” said Talwar. 

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Voyager 2 has reached interstellar space — Future Blink

We couldn’t find the page you were looking for. We found all your missing socks.

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Voyager 2 has reached interstellar space — Future Blink

We couldn’t find the page you were looking for.

We found all your missing socks.

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Shaky California turns on its long-awaited quake alert app

Quakes can’t be predicted. But unassuming Californians can now be alerted that a significant temblor has hit and it’s time to promptly “Drop, Cover, and Hold On” before their world starts shaking. On Thursday, California Governor Gavin Newsom announced the state’s Earthquake Early Warning System, which means Golden State denizens from the northern Redwoods to…

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Shaky California turns on its long-awaited quake alert app

Quakes can’t be predicted. But unassuming Californians can now be alerted that a significant temblor has hit and it’s time to promptly “Drop, Cover, and Hold On” before their world starts shaking.

On Thursday, California Governor Gavin Newsom announced the state’s Earthquake Early Warning System, which means Golden State denizens from the northern Redwoods to the Salton Sea can be alerted of imminent shaking in two major ways.

The first part of the system is the new, free MyShake app (available on iOS and Android phones) which will notify the app’s users about nearby quakes. The second element is Wireless Emergency Alerts which automatically blasts out text messages (the same way you receive an emergency Amber alert) after a quake has been detected. Both alerts, which can give people seconds to tens of seconds of warning, receive quake information from the U.S. Geological Survey’s innovative, sensor-based, ShakeAlert system.

The new MyShake app, developed at the University of California, Berkeley, is a significant, though still prototypical part of California’s quake warning plan. It works, “but it will improve over time,” Richard Allen, director of UC Berkeley’s Seismological Laboratory, said at a press conference Thursday. “We want every Californian to download the MyShake app,” added Mark Ghilarducci, the director of California’s Office of Emergency Services.

“There’s not really a downside,” John Vidale, a seismologist and professor of Earth Sciences at the University of Southern California, said of the app. “Conceivably it could tell us before the shaking starts,” said Vidale, who was not involved in creating the app but has tested earlier versions of quake alert apps.

What’s more, the app uses smartphone sensors to detect significant earthquakes. 

“In addition to alerting you about impending shaking [MyShake] turns your phone into an earthquake sensor,” noted Wendy Bohon, a geologist at the Incorporated Research Institutions for Seismology. Bohon also had no role in developing California’s early warning system.

As the app’s UC Berkeley creators note online, “Our testing has shown that most modern phones in use today can record earthquakes down to magnitude 5 within 10 km of the epicenter.” (A magnitude 5 is a moderate quake “felt by nearly everyone” and will result in some broken dishes and windows, according to the U.S. Geological Survey.) MyShake’s software will get progressively better at identifying quakes as more people use the app.

For now, text messages will be sent out to Californians who feel quakes with an intensity as low as 4.5, a light quake felt by many people indoors. But the MyShake app will send alerts at even lower quake intensities of 3, said UC Berkeley’s Allen. This will match the current alert thresholds of the separate ShakeAlertLA app, released in January exclusively for Los Angeles denizens. The app angered many Angelenos in July when they felt a level 3 quake but didn’t receive alerts. At the time, the L.A. app was set to notify users of shaking intensities of 4 or higher. 

Finding the best alert levels for both text and app systems will require tweaking. “It will not be static,” Governor Newsom said. And there’ll certainly be ample opportunity for finding the ideal alert thresholds, as there will be plenty more quakes

Quake destruction in Northridge in 1994.

Quake destruction in Northridge in 1994.

Image: Chuck Jackson / AP / Shutterstock

The big takeaways 

Any “shake alert” received via text or the MyShake app is only a warning, albeit a potentially major warning.

“The most useful thing is to have your head up [figuratively] and know what’s happening,” said Vidale. “We want people to do sensible things.”

That means dropping to your hands and knees, covering your head and neck with an arm (ideally crawling under sturdy furniture if available), and holding on until the shaking stops.

“ShakeAlert can save lives and reduce the chance of injuries by giving people time to take protective actions like ‘Drop, Cover and Hold on’ before shaking from an earthquake arrives,” said Bohon. “It will also potentially give them time to move away from dangerous or hazardous locations.”

But this early warning system comes with a major limitation, emphasized Bohon. If you’re very close to an earthquake’s epicenter, you may not receive an alert before shaking, or violent shaking, begins. “This is because the system needs time to determine the earthquake’s size and likely shaking levels and it also needs time to distribute the alert,” she said. 

Most Californians live in quake country, so they should already have their plans together. “People should be sure to continue to prepare for earthquakes before they happen,” said Bohon. “The few seconds to tens of seconds that ShakeAlert may provide is obviously not enough time to take critical actions like making an earthquake kit, securing heavy furniture to the walls, bolting the home to the foundation, etc.”

When future quakes hit, Californians now have a new tool in their co-existence with a volatile, incessantly moving earth. 

“Should it work well?” asked Bohom. “Hopefully, yes. ShakeAlert is an innovative technology that will improve over time.”

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The 2019 Fat Bear Week champion is in a league of her own

Welcome to Fat Bear Week 2019! Katmai National Park’s bears spent the summer gorging on 4,500-calorie salmon, and they’ve transformed into rotund giants, some over 1,000 pounds. The park is holding its annual playoff-like competition for the fattest of the fat bears (you can vote online between Oct. 2 and Oct. 8), and Mashable will…

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The 2019 Fat Bear Week champion is in a league of her own

Welcome to Fat Bear Week 2019! Katmai National Park’s bears spent the summer gorging on 4,500-calorie salmon, and they’ve transformed into rotund giants, some over 1,000 pounds. The park is holding its annual playoff-like competition for the fattest of the fat bears (you can vote online between Oct. 2 and Oct. 8), and Mashable will be following the ursine activity. 


Drew Hamilton knew it immediately. 

“Holly is going to win,” he texted me. 

Hamilton, who views bears professionally as an Alaskan bear viewing guide, landed in remote Katmai National and Preserve in late September. He was there to spy the bears before they climbed hills, dug dens, and went into hibernation.

He easily spotted Bear 435 “Holly,” who the park officially announced Tuesday as the winner of the 2019 Fat Bear Week contest. 

“It’s almost like the river got higher when Holly went in the water to catch a fish,” said Hamilton.

“You almost get the sense watching her that she’s getting fatter before your eyes,” he added. 

“It’s almost

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