We're the team behind that viral clip of the giant shark circling the submarine. AUA.

How often does the tag check in with satellites? Do the sharks have to rise to a certain depth for the tag to communicate?

Lucy Howey: There are satellite tags that can report to the satellites when an animal’s at the surface, however, because these are deepwater sharks that never go to the surface, we use archival tags (they’re kind of like a Fitbit in that they’re a small device that records and stores a bunch of data but to send it later). When the tag pops off it sends the data to a satellite.

There’s a small piece of metal that attaches the tag to the animal and after a certain amount of time there’s an electrical current that corrodes the piece of metal and it floats to the surface.

So the tag doesn’t “check in” but the data does take a few weeks to download because there are only short periods of time when satellites are actually overhead to receive the signal over the course of a day, or even how many satellites are available to that part of the planet. It can also take a long time if there’s a lot of data in the tag/if the memory is full.

Thanks! Have you received the data from the tag in the video yet? If so, were you happy with what you found out from it regarding putting less stress on the animal?
Lastly, are sharks the only species that can survive such a wide range of depths? The pressure difference when bringing them to the surface must be huge

Lucy Howey Jordan: We haven’t got the data back yet but—funny story—on the third dive a grouper swam up and tagged itself and we did get data back from that.

Re: “Lastly, are sharks the only species that can survive such a wide range of depths? The pressure difference when bringing them to the surface must be huge”

Dr. Gavin Naylor: That’s a great question. So, fish achieve buoyancy through a gas-filled internal balloon called a swim bladder. If they’re deep sea fish, this naturally expands as they get closer to the surface and causes all sorts of problems (crushes their organs, causes their eyes to pop, etc). Sharks achieve neutral buoyancy by having a huge, very oily liver (the same way oil floats on water—it’s less dense) so it allows them to transition very rapidly from one depth to another. However, just because they’ve got an oily liver doesn’t mean they have don’t have biochemical challenges.

Dean Grubbs: For example, one reason sixgill sharks can survive coming to the surface is because they’re big. My colleague Brendan Talwar has been studying about how a lot of the small deep-water sharks cannot survive being brought to the surface because they get too hot. Their big livers in this case become a hazard. But one reason the sixgill survives is partly because they’re big they don’t get hot as quickly.

Awesome that you all are doing this. Best part of that Sixgill video was how genuinely happy the team looked.
Can/do you live stream these submarine missions? How did you choose where to drop in and go on the submarine?

1. Lee Frey, sub pilot: The truth is we really are genuinely happy to be there. We’re all very fortunate to be able to do something like that. I know I feel that way, and I know Dr. Gavin Naylor was pretty stoked to be down there. We really are all genuinely excited to be there. It wasn’t just for the camera.

2. Not right now, but we’re working on it. The advantage is that these manned submersibles are free-swimming and not connected to the surface with a cable. However, radio frequencies don’t transmit through seawater. So all of the things that people take for granted, like GPS, cell phones, and wi-fi don’t work through seawater. (That’s why the tags have to pop to the surface before they can transmit).

So we’re working with engineers on a way around this. Some people have been developing some technology based on pulses of light instead of radio frequencies. So we’ve been working with them to make that a reality with our new ship OceanXplorer and her subs in the Indian Ocean next year.

1. There are a number of factors that went into it. We had set a big “bait parcel” (a cluster of crates with two chest freezers worth of bait in them) a few days before. The scientists have been studying that area for up to a decade, and kind of knew where they were catching them more frequently than others. Sixgills also do a (nightly) migration from the deeper part of their habitat to shallower waters, and we had previously mapped the area through sonar. So we would try and find a slope where we could park and wait and catch them on their nightly migration.

Interesting, much appreciated for the response! You mention a new ship. What is next (or currently going on) for OceanX?
The manned submersibles.. How custom are they? How deep do they go and how deep have you all brought them? Are you nervous being down that far? Is there a cameraman/woman or it a few cameras set up prior? If it is a person filming is it a shark expert or someone who doesn't know what they got themselves into?

Lee Frey, OceanX sub-pilot: Up until 10 years ago, deep-diving manned submersibles were only owned and operated by governments and big research institutions. There were only a handful of them in the world. Now we have private companies building them commercially. OceanX use subs by Triton Submarines out of Florida (our subs are rated for a maximum depth of 1,000 meters). We’re sort of a sub “superuser”—our sub starts off with a basic platform designed by Triton and we customize it for science and media and do a lot of in-house engineering to expand their capabilities. This is analogous to what’s happening in the space program—for example, SpaceX, Blue Origin, Sierra Nevada are doing stuff previously only done by NASA.

Whenever possible, we try to have a professional cameraperson there because OceanX is all about documenting the scientific work and discovery and exploration in the best possible way we can (lots of this on our YouTube: /oceanx ). It’s part of our mission to have the top science experts and bring their research to life with good media (not just something we would do on our phones...) It’s that combination of these multiple experts on this team that makes our work really unique and successful.

And re: the new ship! Yes! Our new ship OceanXplorer will travel next to the Indian Ocean for our new series for National Geographic, Mission OceanX (working title), which we’re co-producing with BBC and James Cameron. Keep an eye out on our social channels.

Thank you so much for your work and for doing this. What band of the sea does this creature live in, meaning from what depth to what depth? Does it ever surface?

Dr. Dean Grubbs: They don’t ever surface but it’s not the depth that determines their habitat; it’s the temperature. Everywhere we’ve tracked these things they spend their days at 5°C and their nights at 16°C, so whatever depth that corresponds to. In colder climates like the Northeast Pacific they’ll come to depths that divers can actually swim with them. In the Atlantic, off Virginia we tracked them 100 to 400 meters; Hawaii it was 600-250 meters; in Eleuthera, Bahamas, where we tagged them, it’s 400-1200 meters. We deliberately took the sub and waited at a depth where the temperature was ~16°C because we knew that’s where they would head when the sun set. During the day, they’re deeper than the submersible max depth.

How many undiscovered shark species do you think are in the ocean?

Dr Gavin Naylor: The way that you would try to address that is look at the rates at which new species are being discovered over time. And if we are getting close to understanding all of the sharks in the ocean, then it should get slower and slower (the rate of discovery). But it’s not. We’re still discovering them at the same rate. So it’s entirely possible that there are 50 percent of the world’s sharks are yet to be discovered. (PS That's a guess, not an estimate.)

Who names new species, the person who sees it first? If so, any ideas floating around?
Whatever your response, please mark down 1 vote for “The Gavin”

He’s already got a shark named after him! Bythaelurus naylori. But if the shark was named “the Gavin shark” that would be better (“Giant Gavin causes beach shutdown”; a sequel to The Meg; “The Gavin”!)

What bait did you use?

Bonito (tuna).

How large is the shark?

Dr. Dean Grubbs: Which one? There was a lot of them! The night I was in there, there was one that was probably around four meters (13’), maybe a little more. But I think the one in the video—I bet that shark is five meters (~17’) long. We’ve caught ‘em five meters before, and that one looked at least as big as the ones I’ve ever caught.

Lee Frey: From where I was sitting it was as big as the sub is wide—bigger than the sub (4x3m)

Dr. Gavin Naylor: The width of head was nearly as wide as the tray on the front, which is probably about 4-5’.

Dr. Dean Grubbs: When we first did that tagging work in Eleuthera, we tagged a 4m sixgill that got eaten by another shark.

We’re almost certain it was another sixgill because the tag was showing the samer vertical migration (up and down over the course of the day) but the thermal profile was different (there was a time lag in the change of temperature) like it was in the belly of an animal.

If something was big enough to eat a four meter shark to get to that tag, they probably get pretty big.

What else did you see down there?

Gavin Naylor: I saw so many animals down there that I had only ever seen as line drawings in a textbook.

Lee (sub-pilot) did this completely goofy thing, perhaps mostly for my benefit, but it was fantastic: He switched all the lights off and put the thrusters on in the submarine halfway up the water column on the way up. And we had the most spectacular bioluminescence show. It made the New Year fireworks display look like a joke. It was spectacular. All of these things were agitated, and the whole of the sub was shrouded in bioluminescence. That is a pretty cool party trick.

Do you guys get claustrophobic?

Dr. Gavin Naylor: I don’t like going in CT scanners, but that submarine you don’t even know that you’re in a confined space. It’s such a fantastic piece of equipment, you feel like you’re swimming in an aquarium. It’s not really claustrophobic.
Lee Frey (sub pilot): I’ve never had someone get claustrophobic. It’s like you said, it’s like being in an inverted fishbowl. People have said to me they’re claustrophobic and they might get nervous when the sub is lifted off the back deck of the ship, but as soon as we break the surface it disappears. I’ve never had to abort a dive because someone felt claustrophobic.

Dr. Dean Grubbs: I was afraid I would be claustrophobic but not one little bit. Not at all.

Dr. Gavin Naylor: It’s another world, and when you come up to the surface it’s honestly… a little bit disappointing. It’s so magical down there. I’ve never seen anything like it.

I noticed in the TL;DW version they referred to the shark as "her". I'm completely naive to sharks and their characteristics. What are the defining traits between a male and female? Also, is there notable differences between the sexes (like weight, color variations, etc.)?

Gavin Naylor: Anecdotally, when they were feeding off the sub, the large females came in more vertically, were wrestling the bait away from the poles with their head down and their tails up, whereas all the males that we saw came in horizontally. That’s why the one that was tagged was male; its flank was in the right position to shoot the spear gun. There was a very specific area we were aiming for so as not to harm the animal.

What data does the tag collect? Is it’s location when it surfaces recorded to give a rough idea of range of the shark? How can you measure the distance the tagged shark travels?

Lucy Howey Jordan: Depth and temperature. It collects light level too and that’s how you estimate location on the planet (so it matches the level of light to the time of day and the time of year, and so we can tell where the animal is), but for these deep water sharks the light level isn’t as valid.

Dr. Dean Grubbs: But we’ve used it to assess when they’ve recovered. Like when we tag them on the surface, usually that’s a 48 hour period where they’re acting abnormally--their vertical migration is not nearly as well defined. So the tag can still pick up some daylight. But once they settle down and go into their normal vertical (deepwater) movement, they’re out of the range of perceptible light by the tag.

Lucy Howey Jordan: I think it’s crazy to think—when we were bringing those sharks up, fishing for them, it’s the only time they’ve ever, ever seen light.

Dr. Dean Grubbs: It’s the only time they’ve seen light that would be perceptible to us, or to the light sensor on the tag. But in reality they are adapted for detecting really dim blue/green light, so it’s probably daylight to them.

Did you imagine that you would be doing things like this when you started your careers? How did you end up doing something as cool as this?

Our team comes from all kinds of backgrounds.

Some worked in news, some were in the military. Mattie Rodrigue, OceanX Science Associate, says: “I always wanted to be a marine biologist and I never thought I’d be doing anything this cool."

The common thread is that we all are passionate about the ocean.

If you want to have lots of adventures and meet great people, ocean sciences/marine biology are a good bet. The other top careers for getting into this field would be marine engineering, documentary filmmaking, or working on ships/becoming a mariner.

Who was on the submarine and why did you choose those people?

Everyone else was scared. Of Gavin sharks.

In reality there were four shark biologists and four dives. So they all got one each.

But there’s a big team of people both on the sub team side and on the science side. We rotate through. It’s the luck of the draw who’s in the sub when something amazing happens. There’s also a cameraperson because part of OceanX’s mission is to bring the science back to the world through media.

What do you think of Triton submarines? Are you using something similar? Like the 1,000m model:

https://tritonsubs.com/products-services/all-subs/t33003/

We have two subs from Triton!

http://www.oceanx.org/submersibles/

The second one isn't listed here as it's brand new (we only started water trials with it last week). But both our Tritons are 3300/3.

Love working with Triton. Our subs are highly customized and they are great to work with in that regard.

That's great to hear! Going out in a Triton sub and descending to a depth of 1 kilometre is one of my bucket-list dream goals.

To be honest, I'd probably be scared witless, but that's part of the appeal.

Heard a lot of reactions but actually scared is never one (even with a four to five meter shark eyeballing you through the glass). We've been on the ship with some very nervous people and although leading up to the sub dive they were visibly anxious, they ended up relaxing into it as soon as they were in the water. The most common reaction is that it changes you and your perspective on the world forever. That's the magic of ocean exploration.

What an amazing experience you were able to have there. What is it that you most want to know the average person to know about what you observed?

That every time you go down you see something new. In so many ways we've barely scratched the surface of what's in the ocean.

In terms of bananas, how big would you say the shark was?

B-A-N-A-N-A-S. squared.