Night Sharks | Ocean Vet | S01 E08 | Free Documentary

This is Doctor Neil Burnie. He lives in Bermuda, a stunning Atlantic Island
six hundred and forty miles east of North Carolina, USA.He’s spent the last thirty
years practicing veterinary medicine, but now he’s transferring his veterinary skills
to help save, protect, and learn more about the incredible marine life of Bermuda’s
Ocean. This is a completely wild shark. Alongside his dedicated Ocean Vet team, are
a number of scientists, Yeah, this and probably. marine biologists,
Just cut a little nick off the back fin. and specialist master divers, helping to perform
a number of unique and dangerous procedures, in a bid to safeguard critically important
marine species.Together, the team will be fitting satellite tags to huge tiger sharks,
saving precious green turtles, dissecting giant blue marlin, and obtaining unique toxin
samples from forty five tonne, migrating, humpback whales. Yay! Woo hoo!My knees are like jell-o. Yes, man! This is Bermuda! Home to Doctor Neil Burnie, the Ocean Vet. Bermuda’s ocean is home to some of the world’s
most impressive sharks! For millions of years these animals have dominated
the oceanic food chain. Giants, like the tiger shark, rule the deeper
Bermudian seas. Whilst many other incredible species also
call these waters home. But one question remains. Are sharks still found in any numbers at night
in Bermuda’s shallow waters? Yeah, keep it on, because that way you can
drop it. You never know what’s gonna roll up on you
in the darkness. For years, locals have spoken of inshore shark
hotspots.In this episode, Neil, and the team will survey these hotspots, catch any sharks,
and implant tracking tags to reveal if these so-called hotspots are true. Er, to be honest, we were expecting some small
galapagos sharks, we got more than we bargained for! Well, what a rush! Over several gruelling nights, the team, will
battle through sleep deprivation, and dangerous working conditions to collect vital information
on what’s left of Bermuda’s shallow water sharks! So, diving with sharks can be hazardous at
any time, but the danger factor can increase if you’re gonna go in at night. So, we have this purpose built cage to protect
us in the event that something shows up that we’re not expecting, for example, a tiger
shark, or a greater hammerhead. The team are using the boat, Endurance. Crewing a vessel of this size requires all
the Ocean Vet team. So, yeah, we’ll bring it forward, and I
think, um. Series marine biologist, Choy Aming, is captain,
and overseeing all topside operations; Oscar Deuss, is the team’s safety diver and shark
spotter; while, Dylan Ward, is pilot of the support RIB, Harry Lindo; on underwater camera,
it’s Andrew Kirkpatrick. I’ll tell you what. The first time I went down with this guy,
I was scared half bejesus. Er, but the more you go down, just like he
says, the more you get to familiarise yourself with the animals. And now i’m just like stupid excited, like,
I just can’t wait to get back in. So, should be good. The word is exhilarating. Exhilarating. The first shark hotspot and the team’s main
dive site is Castle Harbour. This paradise location opens to the deep ocean
through a deep water channel that passes in the middle of two, old, rocky outposts. In the past, this has been an area where multiple
shallow water shark species have been spotted. In order to study if this location holds a
resident shark population, Neil, plans to utilise an acoustic shark tracking system. So, this is a Vemco VR2W acoustic receiver,
and it will pick up the transmission from any of the sharks that we tag with an acoustic
pinger tag. We’re gonna have two of these receivers
situated about six hundred metres apart at the entrance to, Castle Harbour. And they’ll let us know if any of our tagged
sharks are coming in and out of, Castle Harbour. The acoustic tagging system consists of two
parts. The first is the tracking tag, this is the
part Neil, and the team will have to surgically implant into the abdomen of any sharks caught. The second part is the receiver, this records
the position of any passing tagged sharks.The team are now over the drop-site and ready
to deploy the receiver. So, this is a perfect location. We’ve got the security of these rocks and
a natural reef. We’re gonna place the receiver at the edge
of the reef, and it’s gonna monitor this deep water channel, where the sharks run in
and out at night into, Castle Harbour.I’ve anchored this acoustic receiver to the seafloor
with heavy chains and marked it with GPS. I don’t know what species of shark are in
this area, if any, but it’s possible that galapagos sharks feed around this site. If the team manage to catch and tag any sharks,
this receiver will record their regular passes in and out of this so-called shark hotspot. That was exciting. Er, as the light’s falling it’s looking
a little spooky, because that’s a deep-water channel, which is just the kind of place that
sharks will use as, er, as an advantage when they’re trying to ambush their prey. So, we know for a fact that tiger sharks run
up and down this South Shore, and that’s just the sort of place where a tiger shark
might want to ambush an unsuspecting victim. It’s well documented that sharks are more
active at night, Neil, has therefore decided to run this study from dusk until dawn. But this represents it’s own challenges,
and some new uncharted dangers for the team! Yeah, risks at diving at night, biggest thing,
it’s so easy to get disorientated because you literally have tunnel vision. Really, what ever light source you have, that’s
all you can see, you can’t see anything around. So, it’s easy to get disorientated. It’s easy to lose track of depth. It’s easy to lose track of the surface,
sometimes. So, it can be a real challenge. You got it?It can be a real challenge at night. Um, just kind of doing anything, let alone
chumming up the water, and putting some sharks in the equation. So, um, yeah, we’ll see how it goes, but
definitely a challenge!We’ll try and go at the same time. The first job, is to lower a shark cage to
the seabed. This is to provide underwater protection,
if needed, during the team’s survey dive. Neil, and Oscar guide the cage down to the
seafloor! So, the cage is in position. It’s here for our safety, incase any larger,
aggressive sharks turn up. Although the team’s ultimate goal is to
assess this area for shark numbers, Neil, also knows the project has the potential to
reveal the health of the wider marine ecosystem.Where there’s sharks, there has to be a healthy
food web. Overfishing, and the introduction of invasive
species can destroy these food webs. Where there’s no prey fish, there’s unlikely
to be any sharks. Well, after we set up earlier this afternoon
with our monitoring system, we’ve seen some stuff. And now we’re gonna have a look and see
what actual life there is around the area where we have the cage, right in this channel,
where the water funnels in from the South Shore into Castle Harbour. I’m expecting to see a variety of different
fish, hopefully, and perhaps we’re gonna see some sharks. Yeah, diver’s going in the water! Diver’s in! The first survey dive is taking, Neil, on
a systematic search of the surrounding area. Historically, these inshore waters were heavily
overfished. Neil’s, hoping to find enough biodiversity
to indicate that this site could support a resident shark population. This is a Bermuda spiny lobster. As they grow they shed their exoskeleton. And during this time, they’re highly vulnerable
to predation. And as a result, can be considered shark food. Examples of this kind of shark prey, is a
good start. But, Neil, really needs to find a variety
of fish to be confident of an ecosystem that could support sharks. Here, we have a couple of reef fish exhibiting
the behaviour that’s developed over thousand of years to protect them from night-time predation. These two fish have found a safe little crack
in which to hide. Although Neil has found some interesting marine
species, it’s certainly not the abundance of life he was expecting. So, just completed the first survey dive,
and i’m a little disappointed. We did see a Bermuda spiny lobster, a few
reef fish, er, parrotfish hiding from, hopefully, some predators. But all in all, not quite as much as I wanted. Speckled moray over the sand was very interesting. Good, I checked you. Air’s good, BC’s inflated. Neil, and Kirkpatrick also surveyed a much
deeper location, half a mile, out, past the entrance to Castle Harbour. Worryingly, this deep dive-site provided even
less evidence of sharks, or any potential shark prey. Ugh! There’s nothing down there, even less than
the other spot. Yeah. No ‘lobbies,’ or whatever, and we’re
out of air as well, too. Damn. The team’s disappointment is growing. They’re all concerned about the general
lack of marine life, let alone the lack of any sharks! Either we go to a different spot, or it’s
just not tonight, you know. Everything else ok? Yep. Good man. Just hop back in. Back on Endurance, Neil, is taking a chum
box full of bait down to the shark cage where it will remain for twenty four hours. This is the last ditch attempt to bring in
fish and sharks to the dwindling, Castle Harbour hotspot. There is a possibility we may not find anything
at all, but we’re thinking positive. And we’ve got enough gear and chum, that,
you know, we’re definitely, er, hedging our bets. So, we’re back on our dive-site, it’s
about nine o’ clock. We’ve had the chum in the water now for
over twenty four hours, and we’re really hopeful that tonight’s survey dive will
reveal rather more than we obtained yesterday. We’re hoping there’s gonna be some shark
species around. And what we’re really hoping is that we
can get a couple of galapagos sharks so that we can get the tags implanted. You have to think positive about this, and
that’s what we’re doing. Big step.Diver’s in! All good, Neil? Good man. Ok, so the bait box is still intact. It’s been down here for over twenty four
hours and has no signs of any damage from any large predators. I think we’re going to have to make a move
to a new location. Around four hundred years ago, the numbers
of shark and other fish in this area would have been exponentially higher! Sharks need healthy stocks of prey fish to
survive. Without prey fish, sharks inevitably disappear. Years of exploiting Bermuda’s magical marine
ecosystem has had a profound effect on prey fish and shark numbers. Sharks are vital to the health of our oceans,
they’re the monitors, they make sure that everything stays healthy. Anything that’s genetically wrong. Anything that’s diseased. Anything that’s dying. Anything that’s not up to par, the sharks
are gonna take it out. They keep everything else beneath them, healthy. They keep the populations balanced. You’ve gotta have your apex predators. You’ve gotta have everything from the top-down
in harmony. And that’s why sharks are so important to
us. The team’s new study hotspot sits on the
edge of Bermuda’s shipping channel. Two miles north of the dive-site is Bermuda’s
fringe reef, and two miles south is the shoreline. Neil, has deployed acoustic receivers on several
structures nearby to monitor any successfully tagged sharks. So, we’re here at our new location, just
outside the channel, on the north shore of Bermuda. Andrew, and I are about to go and do a survey
dive, see what kind of reef species we have. And, Choy, is setting up the equipment we’re
gonna use this evening. Yeah, what we’ve got here is, er, a modified
set line. We’re gonna set this up a distance from
the boat, and we’re gonna have to check it, er, probably every fifteen minutes, just
to ensure that the sharks are in as good a shape as possible to come back here. Great! Oscar! Has our chumming station at hand. Plenty of fish going in the water, try and
get some attraction going in this area. And here is our medical centre. We have everything we need here. We’re gonna take DNA samples for analysis,
and more importantly, we’ve got a surgical kit so that we can implant one of these into
the abdominal cavity of the shark. This is an acoustic transmitter tag, and will
enable us to monitor the movement of the shark around the platform. To ensure this shark comes in the best of
health, Dylan, our boat captain, is here in the, Harry Lindo, which we have equipped with
a water hose at the front to keep the shark in good shape. Transport him back to the boat in as quick
amount of possible, to ensure he stays in great health. The baited set-lines are the team’s shark
capture method, they consist of several baited hooks attached to a short line, that’s anchored
to the seabed. So, this is our first bait heading out. This one’s gonna be the closest one to the
reef end. Once the fishing equipment is deployed, Kirkpatrick,
and Neil dive the location. On all accounts, Neil, is much happier with
this site’s biodiversity! So, that was really interesting! More activity here. We found quite a number of small fish swimming
out over the sand, and a lot of slightly bigger fish hiding underneath the reefs; soapfish,
couple of grunts, and some parrotfish. Definitely shark food. So, we’re hopeful this might be the place.Wind’s
made up a little. We’ve got quite a lot of chop to deal with
on the transfers, but, er, we’re hopeful, always hopeful. The stronger winds are causing waves to flood
the RIB, but the set-lines must be checked periodically. Neil, and Choy are out taking a closer look. Do you feel any tension, Neil? Tension on the line could indicate that a
large predator has taken the bait. Oh. Tension! Oh. Neil’s got some tension! Tension! Get somebody on! Tension! Yeah, and they’re down. We had a feeling.I can see something!Ok, we’ve
got a shark! Finally, the team has found what they’ve been
looking for, but the team still aren’t sure what the species is! That’s gotta be a juvenile tiger shark at
that size! That’s incredible! Choy knows how significant this find could
be. A tiger shark of this size could be evidence
of a pupping tiger shark population in Bermuda, something the team have previously had no
evidence of. Well, I’m really excited! This in five years of tagging tiger sharks,
this is the smallest one i’ve ever come across, It’s incredible! So, hopefully we’ll get some fascinating
information out of this guy. This is the smallest by two feet, easily. Juvenile tiger sharks don’t have the capacity
to migrate thousands of miles, consequently, this shark is likely to have been born in
Bermuda. Studying it’s tag data and DNA will be a
remarkable window into the adolescent stage of tiger shark development. Lift, and go!Go! Don’t pull! Keep lifting!Lift and go! Lift and go! Drop the towel on his head! Towel on his head immediately! Perfect. Covering the shark’s eyes is one of Neil’s
techniques to calm the shark down. The team now need to get the shark, up, onto
the medical station to prepare the animal for the tagging procedure. Perfect. Slide them a bit closer together. Get his dorsal in there. Lovely. Excellent.We’ve got a male tiger shark,
juvenile, male, tiger shark. He’s comfortable. He’s in tonic immobility. We have water running over his gills. He had a good bite reflex. Because we actually pulled him back to the
boat from the rib, we actually revived this fish on the way back over here. So the fact that he’s lying still, is not
because he can’t move, it’s because he’s in tonic immobility, when you turn the shark
upside-down. We’re now in an extremely good position
to get the hook out of this fish, and then place our transmitter into his abdominal cavity.Nice
set of dental work, wouldn’t you say?First thing to be done, we’re gonna remove the
circle hook, it’s barbless. We are gonna simply cut it in one place here,
close to the fish, and wind it out. Neil’s primary concern is always the welfare
of the shark. He’s using the same techniques applied during
regular veterinary care, to ensure the shark remains comfortable throughout the tag implant
procedure. Just gonna put a little local anaesthetic
in, just to numb the senses that he has in his body wall, right here.There we go. So, we’re into his body cavity, just get
him cleaned up, then we’re going to be able to insert our tag, it looks pretty large,
but this fish will be able to deal with this fine.Acoustic transmitter is placed. It’s a brief procedure, and although it may
appear uncomfortable for the shark Neil knows first hand just how resilient these animals
can be. We’ve learned over the years that tiger
sharks can suffer pretty profound injury and recover well. We’ve tracked one of our sharks for over
two years after seeing him released with massive fight injuries acquired during tagging. If you lift the lid. The lid is off, that’s the problem. So. There. To confirm this shark is strong enough to
be released, Neil, is making some last-minute health checks. You can see his nictitating membrane coming
across to protect his eye, that’s a good sign. He’s got a bite reflex, just now he bit
down hard on the tube. And you can see this fish’s organs of lorenzini. All these little ampullae around his mouth
and head, those are his electrical sensors, that’s what let him find this bait, together
with his olfactory senses, his sense of smell, through these nostrils right here. Beautiful looking fish! With the health indicators looking strong
and the tag implanted, it’s time to release this juvenile tiger shark. Alright. Slowly, slowly. Yep. He’s coming in. This young shark has certainly been through
quite an ordeal, but the information it will provide could help protect other young tiger
sharks born in Bermuda. There certainly isn’t the numbers of sharks
there once was in these waters, but this young shark is a glimmer of evidence that tiger
sharks aren’t just still living in Bermuda’s shallow waters, but potentially breeding,
and certainly giving birth. That alone, is cause for us to learn more
and better protect these precious, young sharks. Yeah. Ha Ha! So, we came out looking for night sharks in
Bermuda. Er, to be honest, we were expecting some small
galapagos sharks, we got more than we bargained for! Well, what a rush! We just, er, brought a six foot tiger shark
on board, and, er, put an acoustic transmitting tag in it. We’ll be able to see if this fish stays
around the Bermuda platform, in the shallows. Just, wicked! Drew!. The team’s project to study Bermuda’s
shallow water sharks, continues! The mission is to continue the tagging study
and roll-out receivers across the coral platform.The goal is to make Bermuda’s coral platform
one of the most monitored shallow water shark habitats on the planet, providing refuge,
and protection for multiple shark species. Endurance, Endurance, Endurance. Next time on Ocean Vet, Neil, and his crew
are in search of humpback whales. I don’t wanna spook it. It’s right here. Oh my gosh. Utilising a modified compound bow, Neil’s,
objective is to collect blubber samples, and reveal the levels of dangerous man-made toxins
inside these animals. That, is whale blubber! Choy, will also encounter a dead sperm whale
being devoured by hungry sharks. And, Neil, and the crew will dive with several
curious humpbacks, documenting the behaviour, and interactions from one of the oldest animals
in the ocean.

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