- 2 months ago
A scattering of some 700 islands in the Atlantic Ocean, the Bahamas are home to one of the largest and most diverse shark populations on the planet.....
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🐳
AnimalsTranscript
00:04Sharks. Nature's perfect solution to an underwater life.
00:10They've been swimming in the oceans for over 400 million years.
00:14And as top predators, play a vital role in keeping our seas healthy and productive.
00:23But they're coming under increasing pressure. Millions are hunted and killed every year.
00:31Never have sharks needed friends more than they do today.
00:39For three weeks, I've been in the Bahamas for Blue Planet Live.
00:46Watching, monitoring and diving with one of the richest shark populations on the planet.
00:55I want to reveal why sharks are thriving here and find out if there are lessons to be learned from
01:01these crystal clear waters that could help secure their future elsewhere around the world.
01:09En защittel the species of discord
01:09Number 2
01:09Number 1
01:38Number 1
01:38Number 1
01:45Our blue planet is home to more than a thousand species of shark
01:50and their cousins, the rays.
01:57They come in a myriad of shapes
02:04and sizes
02:07and are found across all of our oceans
02:10from the tropics
02:13to the Arctic
02:14and into the deep abyss.
02:21There are a few places where the number and diversity of sharks
02:25is unparalleled.
02:29The Bahamas is one of them
02:31earning it the title of shark diving capital of the world.
02:40700 islands are scattered over 84,000 square miles of ocean.
02:50This location is unique, perched on the edge of deep water
02:55where the seabed plunges to a depth of 4,000 metres.
03:02The meeting of shallow water
03:04and deep, open ocean
03:06leads to a profusion of life.
03:14In winter,
03:16the resident Caribbean reef sharks
03:18and bull sharks
03:20are joined by visitors
03:23bolstering the shark and ray population
03:25to 78 species.
03:42In 2011,
03:43the Bahamas were declared a shark sanctuary,
03:47making it illegal to fish for
03:49or kill
03:50any species of shark.
03:59These protected waters
04:01offer me a unique chance
04:02to get close to
04:04these amazing top predators
04:07and to see first-hand
04:09what it takes
04:10to have a healthy,
04:11thriving population
04:12of sharks.
04:20Within seconds of coming down here,
04:23I'm greeted with one of the most
04:25dazzling displays
04:27you'll ever see underwater.
04:43There's probably two or three
04:45different sort of sharks
04:46at this location,
04:48but the dominant kind
04:49is going to be the Caribbean reef shark.
04:52And I can already see
04:54at least 20 of them
04:55here in the water around us.
04:59And I guess the first question
05:01that people would ask would be
05:03isn't it dangerous?
05:04Isn't it risky
05:05to be surrounded
05:05by this many apex predators?
05:08And I have to say
05:10I feel just as comfortable
05:11being in here
05:12surrounded by all these
05:14extraordinary animals
05:15as I would do
05:16going for a walk
05:17with a pack of poodles.
05:22These animals
05:24are so good
05:25at sensing their environment.
05:27They know what's prey
05:29in the water around them
05:30and it's not us.
05:32They may well swim in close,
05:34but at the last second
05:34they just bank away.
05:36They could not be less interested.
05:39And the statistics about sharks
05:41prove that's true.
05:43Around the world,
05:44you're more likely to be killed
05:46taking a selfie
05:47than you are
05:48to be killed by a shark.
05:51In fact, statistically speaking,
05:54the chance of being killed
05:55by a cow,
05:56a deer
05:57or even a vending machine
05:59is higher
05:59than the risk posed
06:01by one of these.
06:08Sadly,
06:08this abundance of sharks
06:10is not typical
06:11across all of our oceans.
06:15This is not a sight
06:16that you get to see
06:17just anywhere.
06:19So around the world,
06:20we human beings
06:21are taking at least
06:22100 million sharks
06:24from the world's oceans
06:25every single year.
06:29In some places,
06:30sharks have declined
06:32by over 90%.
06:34And in the time
06:35it'll take
06:36for you to watch
06:36this programme,
06:38over 11,500
06:40will be killed.
06:43It's a number
06:44that simply
06:45cannot be sustained.
06:46If it carries on like this,
06:47then our children
06:49will not have
06:50the opportunity
06:50to die in seas like this,
06:52surrounded
06:53by these stunning predators.
06:57The Bahamas
06:58isn't the only place
06:59to offer protection
07:00to sharks.
07:02Today,
07:03a total of 17 sanctuaries
07:05have been created
07:06around the world,
07:07covering over
07:08seven and a half
07:08million square miles.
07:12But this still amounts
07:14to only 5%
07:15of our oceans.
07:19Sharks need more help.
07:22And if we don't give it to them,
07:24much of the life
07:25in our oceans
07:25will suffer.
07:28As apex predators,
07:30they remove
07:31any sick or injured animals,
07:33keeping fish stocks healthy.
07:36Animals below them
07:37in the food chain
07:38are kept in check
07:39and removing sharks
07:41would unbalance
07:43whole ecosystems.
07:46Over 3 billion people
07:48depend on the ocean
07:49for their livelihoods.
07:52It's essential
07:53we protect sharks
07:54for our sake
07:55as well as theirs.
07:58And a vital step
07:59towards this
08:00is combating
08:01the reputation
08:02temptation of fear
08:03that many sharks
08:04still hold.
08:17I always had
08:19a passion
08:19for the ocean.
08:21I fell in love
08:22with scuba diving.
08:24I fell in love
08:24with everything.
08:26It was a calling,
08:28I think.
08:37Christina Zanato
08:38left her homeland
08:39of Italy
08:40over 20 years ago
08:41heading for the Bahamas.
08:46Ever since,
08:47she's become
08:48an advocate
08:48for sharks.
09:00And two decades
09:01of diving
09:02at one site
09:03off the island
09:03of Grand Bahama
09:04has convinced her
09:06that these animals
09:06are a long way
09:08from being
09:09mindless killers.
09:13Christina is known
09:15locally
09:15as the shark dancer.
09:21And this
09:22is her stage.
09:25I love
09:26that there is
09:28a busy silence.
09:37It is
09:38the most peaceful
09:40and calming
09:41moment of my day.
09:47My babies
09:48are Caribbean
09:50reef sharks.
09:53I love
09:55watching
09:55their behaviours
09:57and their interactions.
10:01They appear
10:02to me
10:03as different
10:04as any other
10:05human being
10:06that I encounter.
10:08Some of them
10:09are more dominant.
10:11Some of them
10:12are shy.
10:15And some
10:16seemingly seek out
10:17a closer encounter
10:19with Christina.
10:22The first time
10:24that shark
10:25settles in my lap
10:28and every time
10:29she settles
10:30in my lap
10:31and I feel
10:31her weight
10:32over my legs,
10:33that is
10:34the most
10:35amazing feeling.
10:37And there's
10:38nothing
10:38to this day
10:39that beats that.
10:45you can feel
10:47everything about
10:48the shark.
10:48You can feel
10:49that it is
10:50a living,
10:51breathing creature
10:52that is aware
10:54of her surroundings,
10:55that is aware
10:56of what I am doing
10:58to her,
10:59that is aware
11:00of my touch.
11:01And the suit
11:02might actually
11:03have a nice feeling
11:04to their skin.
11:07the sharks
11:08are eight feet long.
11:10I can never force
11:12an animal
11:12of that size
11:13to do anything
11:15or to sit anywhere.
11:18It's their decision
11:19to come in.
11:20It's their decision
11:21to stay.
11:22It's their decision
11:23to go.
11:29There is
11:30a total disconnect
11:31from humans
11:33to sharks.
11:37We can swim
11:38in the ocean
11:39with sharks
11:39in a way
11:40that you can never
11:40walk around
11:41on the snow
11:43with a polar bear
11:44following you.
11:47We have to make
11:48that connection
11:49with the sharks.
11:51Understanding
11:51they're way,
11:52way less dangerous
11:53than many creatures
11:54out there.
11:59Christina's
12:00unique relationship
12:01with sharks
12:01allows her
12:03to do something
12:03quite extraordinary.
12:13She can take out
12:14fishing hooks
12:16that are caught
12:17in their mouths.
12:25Over the years
12:27she's removed
12:28more than 300 hooks.
12:41We must change
12:42our ways
12:42because we need
12:44to protect the oceans
12:45and we need
12:45to protect the sharks.
12:47And when you reach
12:48that message
12:50then you have a victory.
12:57a greater understanding
12:58of these
12:59misunderstood creatures
13:00can undoubtedly
13:02help sharks.
13:06And with such
13:08a diverse
13:08and healthy population
13:09on its doorstep
13:13the Bahamas
13:14has long been
13:15at the forefront
13:16of global shark research.
13:21The Bimini Biological
13:22Field Station
13:23or Shark Lab
13:25has been increasing
13:26our knowledge
13:27of sharks
13:27and rays
13:28for the last 29 years.
13:37Heading this institute
13:38is Matt Smuckle
13:39who's had a passion
13:40for the marine world
13:41for as long
13:42as he can remember.
13:45My first memories
13:46were snorkeling
13:47in the Florida Keys.
13:48Growing up
13:49I always had
13:49an affinity
13:50and a connection
13:51with spending
13:52pretty much
13:52every weekend
13:53and all summer
13:54in the ocean.
13:55My favorite group
13:56of animals
13:56are the sharks.
13:57That's what originally
13:59brought me to the Shark Lab.
14:00That's what makes me
14:00enjoy waking up every day
14:01and doing this job.
14:04The Bimini Shark Lab
14:05started in 1990.
14:07Right now
14:08at the Shark Lab
14:09we're studying everything
14:10from southern stingrays
14:11to bull sharks
14:12tiger sharks
14:13lemon sharks
14:14hammerheads
14:14but we take it
14:16from a very
14:17ecosystem driven model
14:19where we want
14:20to understand
14:20everything that's going
14:21on around Bimini
14:22and how that's
14:23impacting these big sharks.
14:29One of the biggest
14:30and most impressive species
14:31and the focus
14:33for a number
14:33of Shark Lab's studies
14:34can be found
14:36a stone's throw
14:36from the heart
14:37of a busy marina.
14:46These are bull sharks
14:49drawn in by the scraps
14:51discarded from fishing boats.
14:55They spend much of their lives
14:57in murky estuaries
15:00so this clear water
15:02gives me a unique opportunity
15:03to see them up close
15:05and Matt
15:06a chance to learn
15:07more about this
15:08little understood
15:09species of shark.
15:13I'm here
15:14on the bottom
15:15of the harbour
15:16and as you can probably see
15:18I'm absolutely
15:20surrounded
15:20by bull sharks.
15:28this is an opportunist
15:30that has a very
15:32wide array
15:33of different kinds
15:34of prey
15:34so they'll feed
15:36on fish
15:36on rays
15:37on birds
15:39at the surface
15:40on dolphins
15:41they'll even
15:42bite through
15:43the shells
15:44of turtles
15:45now
15:46all the sharks
15:47that I'm seeing
15:48around me
15:48at the moment
15:49are females
15:50I haven't seen
15:51a single male
15:53and they're quite
15:54big
15:55in the belly
15:59why the warm waters
16:00of the Bahamas
16:01attract these large
16:03slightly rotund females
16:04has long been a mystery
16:07one Matt and his team
16:08from shark lab
16:09are hoping to solve
16:11but to do that
16:12they first
16:13have to catch one
16:16to go ahead
16:17and catch
16:18say a big
16:18female bull shark
16:20what we'll do
16:21is drop a baited hook
16:22throw it right in
16:23and they pretty quickly
16:24will normally
16:24take the hook
16:31all right
16:31on on on
16:33hooking the bull shark
16:34is the easy part
16:35as soon as they start
16:37running around
16:38with the balls
16:38and the rope
16:39this is a bit of a dance
16:41between the person
16:41bringing it in
16:42and the shark
16:55we have to be very careful
16:56because they are not
16:57expecting to be caught
16:58and handled by humans
17:03in order to help
17:04number one
17:04for human safety
17:05but also for shark safety
17:07we'll put a tail rope
17:08on
17:09that helps to secure
17:10the shark
17:10to the boat
17:18with the shark
17:19safely harnessed
17:21and calm
17:21the team can take
17:22measurements
17:23and assess
17:24the shark's condition
17:27and one of the most
17:29crucial jobs
17:29is to find out
17:31her reproductive state
17:34using a very familiar method
17:38ultrasound
17:42so I think
17:43there's something
17:44right there
17:48so you can see it
17:49moving slightly there
17:50that looks like the pup
17:55over 50%
17:57of the females
17:58that we catch
17:59are actually pregnant
18:01they have paired uterus
18:03so we check both sides
18:04and we're going to try
18:05to count the number
18:06of pups
18:07that we can see
18:08the size of pups
18:09and both sides
18:09to get a better understanding
18:10of her offspring litter
18:14after 10 months
18:16bull sharks give birth
18:17to up to 13 pups
18:21these fully formed
18:22pint-sized sharks
18:23are then left
18:25to fend for themselves
18:29now that we've confirmed
18:30she's pregnant
18:31we're going to go ahead
18:31and let her go on her way
18:33give her a push
18:36all right
18:37nice job
18:40at the end of the procedure
18:41it's great to be able
18:42to give that shark a push
18:44we're blessed here
18:45with beautiful clear water
18:46and we can always observe
18:47the shark
18:47basically follow her
18:48to make sure
18:49that she's swimming strong
18:50and that she's doing well
18:53and it's not just
18:55the visiting bull sharks
18:56who are carrying
18:57the next generation
19:03many other species
19:04found in the bahamas
19:05are also pregnant
19:12it's thought that the warm waters
19:14and rich feeding grounds here
19:16help raise the shark's metabolism
19:18and speed up gestation
19:30we know a lot about sharks
19:32but there's so much more
19:33that we still need to understand
19:34we still don't even know
19:36some of the basic reproductive biology
19:38some of their life history things
19:40and these are all very important
19:41for conservation
19:42and this is what really is going to help us
19:45manage the next generation of sharks
19:49and it's managing this next generation
19:51and the habitats that are essential
19:53to their survival
19:54that's vital to maintaining
19:56a healthy population of sharks
20:14this tangled mass of roots
20:16is the mangroves
20:18it's an environment that changes constantly
20:21with the tides throughout the day
20:23and provides the perfect spot
20:25for baby marine animals
20:27to hide out in
20:30I'm joining Clemency White
20:32from Bimini's Shark Lab
20:34to see how these mangroves
20:35are key to the success of sharks
20:37in the Bahamas
20:42whoa, look at that
20:45yep, they're all waiting for us
20:47baby sharks
20:50that's absolutely incredible
20:57these are lemon sharks
20:59and they've been studied
21:00by Clemency and her fellow researchers
21:02for over 30 years
21:06it looks like they want to be fed
21:09yep, we actually have a little bit of squid
21:10if you wanted to give it a go
21:11I would genuinely love to
21:17so Clemency, how old are the sharks
21:19we're looking at here
21:20so most of these sharks
21:21are in their first few years of life
21:22so the majority of them
21:23will be maybe two or three years old
21:25and some of those larger sharks
21:26you can see are maybe four or five
21:28so this is a refuge
21:29this is an area
21:30that's pretty much only accessible
21:31to these guys at high tide
21:33so that small narrow walkway
21:34that we walked in
21:35bigger sharks can't use that
21:37what sort of things
21:38are they taking shelter from?
21:39the biggest predator
21:40of juvenile lemon sharks
21:41is actually lemon sharks themselves
21:42adult lemon sharks
21:43so they're cannibalistic
21:44yes, they are cannibalistic
21:46and also other large sharks
21:48so maybe bull sharks
21:50other species like that
21:52so this genuinely is a nursery
21:54it's a place where the youngsters
21:56are safe from other
21:57that went right between my legs
22:00I should be wearing a cricket box
22:02or something
22:02um, you're okay
22:05no!
22:07seriously
22:08they're all just making a beeline
22:10straight between my legs
22:12this would be a disaster
22:13if all the things I've done in my life
22:15and I was to get savaged
22:16in the ghoulies
22:17by a baby shark
22:18well they must like you
22:21that one there is a decent size
22:23yeah, so they'll be pretty loyal
22:25to the mangroves
22:25that they were born in
22:26until they're about 13 years old
22:27when they're sexually mature
22:28and then they'll also come back
22:30to give birth here as adults
22:31so they really rely on those mangroves
22:32for their entire life cycle
22:33what are the main threats
22:35to mangroves in the Bahamas?
22:37so a lot of places
22:38even in Bimini
22:39we see the mangroves
22:40are being removed
22:41to facilitate bigger hotels
22:42and bigger resorts
22:43and that in itself
22:45means that these pups
22:46will still be born in the same place
22:47they'll still be used in the same areas
22:48but they won't have that same security
22:50from the larger fish
22:51so, lose the mangroves
22:53and you lose the lemon sharks
22:54yep
22:58it may not look like
23:00any other nursery you've seen before
23:02but you can see how vital
23:04this environment is
23:05to these rather wonderful
23:07and surprisingly cute animals
23:17all over the world
23:18baby sharks and rays
23:20seek refuge in mangroves
23:22seagrass
23:23and estuaries
23:30throughout their lives
23:32sharks need a whole variety
23:34of ocean habitats
23:37and protecting these
23:39is essential
23:39if shark numbers
23:41are to bounce back
23:54most sharks
23:55take many years
23:56to reach sexual maturity
23:59female great white sharks
24:01need a whopping
24:0233 years
24:04before they can breed
24:07this combined
24:08with their tendency
24:09to produce
24:10just a few offspring
24:11means that shark populations
24:13are extremely vulnerable
24:15to overfishing
24:39right now
24:40sharks are being killed
24:42at a staggering rate
24:54they're deliberately caught
24:55for food
24:58and accidentally caught
25:00in nets
25:00or long lines
25:02set for other species
25:09they're also harvested
25:11in their millions
25:12for their fins
25:14to make shark fin soup
25:16a delicacy
25:18that's seen shark fins
25:19sell for $650 a kilo
25:28fueling a cruel
25:30wasteful trade
25:31which sees the rest of the shark
25:34being thrown back into the sea
25:37often still alive
25:40often still alive
25:42a third of all shark species
25:45are now threatened
25:46with extinction
25:48and this is being driven
25:50by human activities
26:08but all is not yet lost
26:10there is hope
26:12and it comes from the fact
26:14that these sharks
26:15can be worth more alive
26:17than dead
26:33I'm heading 12 miles north
26:35of Grand Bahama
26:36to a site of global importance
26:50this could well be
26:51the best shark dive
26:53in the whole world
26:55and what happens here
26:57is key to securing
26:58the future of sharks
27:00right across the world
27:03oh great hammerhead
27:06amazing
27:08look at that
27:10powering straight in
27:12that is just extraordinary
27:17drawn to the warm
27:18productive waters
27:20this is also the best place
27:22in the world
27:23to see tiger sharks
27:28a tiger shark is
27:30unmistakable in form
27:31it has
27:33the dappling
27:34running down its sides
27:35which gives it
27:37its tiger name
27:39their feet are just about
27:41anything they can find
27:42in the water
27:43and with those teeth
27:45they can even
27:46go through the shell
27:48of a turtle
27:50this is
27:52absolutely dazzling
27:53I don't know
27:55which way to look
27:56tiger sharks
27:57great hammerheads
27:58lemons
27:59bull sharks
28:00reese sharks
28:03it's the world's
28:05greatest safari
28:06it just
28:06all happens
28:07underwater
28:10here and throughout
28:11the Bahamas
28:12sharks are drawn in
28:14with food
28:14so tourists
28:16can reliably
28:16get close to them
28:22feeding of sharks
28:24is a hotly debated
28:26topic
28:27there's people
28:28who think
28:29that it's a bad idea
28:30and might
28:31potentially change
28:32the behaviour of sharks
28:34and I can totally see that
28:35but there's no doubt
28:37that shark tourism
28:39here in the Bahamas
28:40is incredibly important
28:44each year
28:4520,000 people
28:46come to the Bahamas
28:47to dive with sharks
28:49making it the largest
28:51shark diving industry
28:52in the world
28:54shark diving
28:56here in the Bahamas
28:57is worth
28:58an estimated
29:00114 million
29:02dollars every year
29:03to the local economy
29:07unquestionably
29:08the sharks
29:08are worth
29:10more alive
29:10than they are dead
29:13and that's hugely
29:14important
29:14for the survival
29:15of these extraordinary
29:16animals
29:38all across the world
29:39shark tourism
29:40is fast becoming
29:41a thriving industry
29:43not just for dive operators
29:45but boat drivers
29:47hotels
29:48restaurants
29:49and bringing much needed
29:51income
29:51to shark hot spots
29:52from all over the world
29:57came from Philadelphia today
29:59to swim with sharks
30:00and it is just invigorating
30:02it's a whole other world
30:04down there
30:10I'm from Argentina
30:12so it was a long free
30:14but it's amazing
30:18it's estimated
30:19that well over
30:20half a million people
30:21come to watch sharks
30:23every year
30:24not only are sharks
30:26gaining more advocates
30:27but they now hold
30:28an indisputable
30:29monetary value
30:34and this will certainly help
30:36to secure their future
30:44shark conservation
30:45is something that will require human effort
30:47for many years to come
30:49and right here in the Bahamas
30:51there's a very special project
30:53that's training up the next generation
30:55of shark champions
31:01marine biologist
31:03Gillian Morris
31:04has set up
31:05Sharks for Kids
31:10a charity
31:11to show children
31:11across the Bahamas
31:12that sharks
31:13are something to celebrate
31:15not to fear
31:18I really believe
31:20that the best way
31:21to change
31:22the way people see sharks
31:23is to let them
31:25get in the water
31:30we take kids out
31:31to see sharks
31:32and a lot of them
31:33are very afraid
31:34they don't want to
31:35get off the boat
31:36they don't want to
31:36step off the beach
31:37and we get them to put a mask
31:39and a snorkel on
31:40and we kind of ease them in
31:41and then they're snorkeling around
31:43and they're seeing the sharks
31:44and the rays up close
31:45and realizing
31:46they're not trying to attack them
31:48but they're actually
31:49really beautiful animals
32:03it's really incredible
32:04to see students go
32:04from being terrified
32:05and not wanting to get in the water
32:07to we're having to drag them out
32:09we've got to go
32:10it's time to go home
32:11and to see that transition happen
32:13right in front of you
32:14very quickly
32:15is really really powerful
32:19the bahamas is a shark sanctuary
32:21which is incredible
32:22and has set a standard
32:24around the world
32:25for shark conservation
32:26shark diving
32:27shark science
32:28and so it's vital
32:30to have the locals involved
32:32at all levels
32:33from kids to adults
32:34to protect the future
32:36of this sanctuary
32:37and the sharks here
32:38in the bahamas
32:49while places like the bahamas
32:51offer protection
32:52when the sharks are here
32:55once beyond the invisible
32:57boundary of the sanctuary
32:58sharks are immediately vulnerable
33:04knowing where they go
33:05in this vast
33:06featureless landscape
33:07is essential
33:09if we're to offer them protection
33:14a few miles off the coast of Andros
33:16the endless blue
33:18is interrupted
33:21by a naval boy
33:30this lone beacon
33:31is a big draw
33:33for passing travellers
33:37providing shelter
33:39for schools of fish
33:42which attract
33:43the hunters
33:45top of the food chain
33:47out here
33:47are these
33:48silky sharks
33:52they get their name
33:54from the silky sheen
33:55of their skin
34:01so little is known
34:02about the migrations
34:03of these
34:04open ocean drifters
34:09when shark biologist
34:11Tristan Gutteridge
34:12heard rumours
34:13of this location
34:15it was an opportunity
34:16for him to try
34:17and uncover
34:17these secrets
34:19which might just help
34:20protect
34:21these threatened sharks
34:27there's nothing that gives me
34:29more energy
34:30than being in the water
34:31with sharks
34:37these silky sharks
34:38they're a completely
34:39different type of animal
34:43there's just something
34:44about them
34:45that brings them closer
34:46and draws them into you
34:51they have this curious
34:53bold personality
34:54and it is a bit
34:56intoxicating
34:56and I love it
34:59but this inquisitiveness
35:01is this shark's
35:03Achilles heel
35:05silkies are in trouble
35:07globally
35:07and in fact
35:08silky sharks
35:09are the second highest
35:10caught shark species
35:12in the world
35:15industrial fishing
35:16often uses
35:17floating objects
35:18working just like
35:19the naval boy
35:20to attract and aggregate
35:22fish like tuna
35:23in the open ocean
35:27but they don't just
35:28attract tuna
35:31every year
35:32hundreds of thousands
35:34of silky sharks
35:35get accidentally caught
35:37I see the evidence
35:39of the pressures
35:40that these animals
35:41are under
35:42from the hooks
35:43in the mouths
35:44and the leader wire
35:45that's coming out of it
35:46you can see these sharks
35:48they're in trouble
35:49they've got a lot
35:50to deal with
35:51out in the open ocean
35:54Tristan wants to catch
35:56a shark
35:56in order to attach
35:57a tracker
35:58which will reveal
35:59for the first time
36:00where these curious
36:02sharks go
36:06one method
36:07that we can use
36:08to catch silkies
36:09is you can actually
36:10bend the top
36:11of the tail
36:12over
36:13and it sends them
36:14into this kind of
36:15bizarre trance-like state
36:17and if you turn them
36:18upside down
36:19at the same time
36:20then they're almost
36:21playing dead
36:22they're just out
36:23it's not fully understood
36:25why
36:25but many shark species
36:27enter this trance-like state
36:29called tonic immobility
36:31when upside down
36:32enabling the team
36:33to tether the shark
36:34next to the boat
36:35free portal
36:42a satellite tag
36:43is fixed
36:44to its dorsal fin
36:46every five minutes
36:48this tag will record
36:49important information
36:50including depth
36:51light level
36:53and water temperature
36:58after 30 days
36:59it'll pop to the surface
37:00and start sending
37:02a stream of data
37:03to tristan
37:06there's nothing more
37:07exciting than
37:08in the few days
37:09when you know
37:09a tag is going to pop
37:11as to where
37:11it's going to pop
37:13it's very important
37:15that we learn more
37:16about their migration
37:17patterns
37:18their population structure
37:19in order to try and put
37:21management measures in place
37:22to improve their conservation
37:27they deserve to be
37:29on this planet
37:30like us
37:31and like anything
37:32they deserve to be here
37:33and we as humans
37:35should be responsible
37:37so it is critical
37:39that we learn more
37:40about these animals
37:41and it's critical
37:42that we protect them
37:47Tristan's tags
37:48have shown that
37:48these sharks
37:49not only traverse oceans
37:52but dive down
37:53to feed at depths
37:54of over 400 metres
37:58showing that
37:59if we want to
38:00protect sharks
38:01we need to look after
38:02every part of our oceans
38:13satellite tags
38:14satellite tags are now
38:14being deployed
38:15on many different
38:16species of sharks
38:17and they're revealing
38:18some incredible journeys
38:23the greatest distance
38:25ever recorded
38:26was by a great white shark
38:28named Nicole
38:29who swam from South Africa
38:31to Australia
38:32and back again
38:34a staggering 12,000 miles
38:37in just nine months
38:48while understanding
38:49where these top predators
38:50go is important
38:52another vital piece
38:54of this conservation puzzle
38:55is understanding
38:56why they go
39:07just off the coast
39:08of Bimini
39:09in the Bahamas
39:10there's a dive site
39:11that for a few months
39:13each year
39:13provides a close encounter
39:15with one of our most iconic
39:17and well-known
39:18migratory sharks
39:24this is the only place
39:26in the whole world
39:26where you can reliably see
39:28great hammerhead sharks
39:33so we have dozens of sharks
39:34around us
39:35most are like this one here
39:38it's a nurse shark
39:41and the reason they have
39:42this name
39:43is that when they're feeding
39:44they make a sucking noise
39:47kind of like a baby
39:49when it's nursing
39:50when it's feeding
39:52you can see
39:53that they're quite content
39:54lying on the bottom
39:55they can pump water
39:57through their gills
39:59and they don't have to
40:00swim constantly
40:01in order to breathe
40:03like many other sharks do
40:06but this creature
40:08that's heading towards us now
40:10that really is the main event
40:13it's a great hammerhead
40:16there are
40:18at least three of them
40:19around us
40:21right now
40:22and while the nurse sharks
40:23are quite dopey
40:26and just hang out on the bottom
40:28this is a far more targeted predator
40:32there is nothing else
40:33quite like the great hammerhead shark
40:35the shape of the head
40:37the giant dorsal fin
40:40it's so unusual looking
40:42and yet
40:43so perfectly adapted
40:45to its job
40:47shaking the hammerhead
40:49from side to side
40:50as it moves along the bottom
40:51sensing
40:52the potential moving muscles
40:54of its prey
41:02perhaps the most incredible thing
41:04about this
41:05is that
41:05great hammerheads
41:06are an endangered species
41:09there are very very few
41:11of these almighty sharks
41:13left in the whole world
41:16and right now
41:17I think we have seven
41:21I don't quite know what to say
41:24I'm completely blown away
41:32these great hammerheads
41:34are seasonal visitors
41:35spending the winter months here
41:37between December and April
41:42many return
41:44year after year
41:49the scientists
41:50have at least 30 individuals
41:52that they know by name
41:55and not just by name
41:57but by personality
41:58and character and behaviour
42:02and even in the short time
42:03since I've been here
42:05I've been starting to get to know
42:07the individual personalities here
42:10you might not think of a shark
42:12as having a personality
42:13but they very much do
42:14some of them
42:16are quite bold
42:18and dramatic
42:19and others
42:19are real gentle giants
42:24this almighty grey hammerhead here
42:27is called Gaia
42:28she's a female
42:31and the largest that they see here
42:36what an absolute beauty
42:43I will never ever get tired of this
42:49holy moly
42:55for five months of the year
42:57these hammerheads are seen
42:59virtually every day
43:01but in April
43:03they suddenly disappear
43:16one female was tagged here
43:18at Bimini
43:19she then headed north
43:20to the coast of the Carolinas
43:22before turning south again
43:24ending up off the coast of Florida
43:27a journey of over 3,000 miles
43:29in less than two months
43:39but what's causing these ocean wanderers
43:42to travel so far
43:43and so fast
43:51I'm taking to the air
43:52to find out
44:01this is Palm Beach, Florida
44:04it's a playground for the rich
44:06and the famous
44:07but little do they know
44:08that just off the coast
44:09is one of the greatest gatherings
44:11of large predators
44:13on the planet
44:22these are blacktip sharks
44:31massing in their thousands
44:33before migrating north
44:34to their summer feeding grounds
44:36off the coast of North Carolina
44:40it's these sharks
44:41that attract a host
44:43of larger predatory sharks
44:44including the great hammerheads
44:46which travel from the Bahamas
44:48to feast on this bounty of food
44:54I joined Stephen Kudura
44:56a professor at Florida Atlantic University
45:00each year he takes to the air
45:02to monitor the number of sharks
45:07just a slick
45:09of sharks
45:10going on all the way
45:12parallel to the coast
45:13that is absolutely fantastic
45:16they stand out so well
45:18against the sandy bottom
45:19don't they?
45:20that's one of the reasons
45:21we're so successful
45:22with the aerial surveys here
45:23we have clear water
45:24a light sandy bottom
45:26you're able to see everything
45:27and they're in nice and shallow
45:28and they're nice and shallow
45:29they really make it easy for you
45:30don't they?
45:32but all's not what it seems
45:35Stephen's long-term study
45:36has shown that this
45:37spectacular migration
45:39is changing
45:41and this could have
45:42serious consequences
45:44I've been doing these aerial surveys
45:46for the last nine years
45:47and we've seen this decline
45:49in the number of sharks
45:50over the past nine years
45:52at the same time
45:53we've seen an increase
45:54in the water temperature
45:55down here
45:55they have a very narrow
45:57thermal tolerance
45:58they like water
45:58between about 21 to 25 Celsius
46:01and as water temperatures
46:03keep rising
46:03we're getting fewer and fewer
46:04sharks coming this far south
46:07presumably the black tips
46:08that you've got here
46:09there are constant interactions
46:10between them
46:11and the larger predatory sharks
46:12like the tigers
46:13the great hammerheads
46:14and the bulls
46:15how is that likely
46:16to be affected?
46:17that's a really good question
46:18if you don't have these
46:20black tips sweeping down here
46:22in the tens of thousands
46:23every spring
46:23there's no food
46:24for the big hammerheads
46:25and these black tips
46:27are not eating all the baitfish
46:28and so we don't even know
46:30what might happen
46:36you know these ecosystems
46:37have remained pretty much
46:38unchanged for millennia
46:40but they are dramatically changing
46:42in my lifetime
46:43and where that will lead
46:44we simply don't know
46:53the rate at which our seas
46:55are heating up
46:55is accelerating
46:58and the effects of this warming
47:00are now being felt
47:01in every one of our oceans
47:17sharks are under pressure
47:19from all sides
47:20fishing
47:21their habitats changing
47:23and now in these protected waters
47:26their fellow sea creatures
47:34recently
47:35an unwanted visitor
47:37has appeared in Caribbean waters
47:45this is a lionfish
47:51a predator
47:53that could eat
47:54fish populations
47:55out of existence
47:57threatening the future
47:59of the resident sharks
48:0710 years ago
48:08I saw for myself
48:09just what devastating
48:11predators they are
48:12in their native waters
48:14off Malaysia
48:16there's a small fish
48:18over here
48:18the lionfish
48:20has spotted it
48:22this could be trouble
48:24it's moving in
48:27oh
48:30unbelievable
48:30did you see
48:32the speed of that strike
48:36lionfish
48:37eat about 70 different species
48:39of fish
48:40and invertebrate
48:44if it fits in their mouth
48:46they'll eat it
48:52you did it again
48:55this is just the most
48:57astounding
48:58display of feeding
48:59I think I've never seen
49:09such an elegant fish
49:11is unsurprisingly
49:12a favourite
49:13of the aquarium trade
49:15and in the 1980s
49:17a few unwanted pets
49:19ended up being released
49:20in the seas
49:21of Florida
49:24with devastating results
49:30in just over 30 years
49:32they've spread from
49:34coastal Florida
49:34with alarming speed
49:38they're now found
49:39as far north
49:40as New York
49:41and south
49:42to Brazil
49:44this is the wrong fish
49:46in the wrong place
49:48and at the wrong time
49:53and it's threatening
49:54to unbalance
49:55the already fragile system
49:57upon which
49:58the sharks depend
50:03this is a growing problem
50:05that people
50:06like marine biologist
50:07Alex Fogg
50:08are trying to find
50:09a solution to
50:11the reefs have changed
50:12actually quite a bit
50:13since I first started diving
50:14I started diving
50:14about 10 years ago
50:16and in this area
50:17in particular
50:18lionfish weren't here yet
50:26when we first started
50:28seeing lionfish
50:28on the reef
50:29it was one here
50:30one there
50:30but now you go
50:31to a reef site
50:32you can see upwards
50:33of 100 lionfish
50:34I mean they're here
50:35eating everything
50:36it's like a
50:37all you can eat buffet
50:38if you will
50:41they're not just
50:42voracious hunters
50:43they're prolific breeders
50:45too
50:46a female lionfish
50:48can lay more than
50:4920,000 eggs
50:51every four days
50:55they can reach densities
50:56of over 200 adults
50:58per acre of reef
50:59and that quantity
51:01can hoover up
51:02nearly half a million
51:03fish a year
51:08this is having
51:09a devastating effect
51:10on an already
51:11fragile ecosystem
51:13but Alex has a plan
51:20you can't really catch
51:21them on hook and line
51:22there's really only one
51:23way to harvest lionfish
51:24and that's through diving
51:25and harvesting with spears
51:32and all these fish
51:34don't go to waste
51:38lionfish are definitely
51:39one of the most
51:39environmentally friendly
51:40fish that you can
51:41actually eat
51:44this is one fish
51:45that we want to eat
51:46into extinction
51:48hey chef
51:48got you a bunch of fish
51:49alright man
51:50appreciate it
51:50thank you very much
51:51thank you
51:58Alex hopes that by
51:59making a commercial
52:00market for these
52:01lionfish
52:02more will be caught
52:04allowing reefs
52:05and sharks
52:06to recover
52:1010 years down the road
52:11from now
52:13lionfish are still
52:13going to be here
52:14are they going to be
52:15at the numbers
52:15that we have today
52:16I'm not sure
52:17I think that
52:18if we can just get
52:19lionfish to a point
52:20to where the ecosystem
52:21can actually deal
52:22with it
52:22or they find their
52:23space in the ecosystem
52:24that's our best bet
52:28the market for lionfish
52:29and restaurants is growing
52:32but to fully combat
52:33this invasion
52:34things are being taken
52:36a step further
52:45along the coast of America
52:46locals have created
52:48lionfish derbies
52:52the aim
52:53to collect
52:54and remove
52:55as many lionfish
52:56as possible
53:06each fish is measured
53:08and prizes are awarded
53:09for catching the most
53:10the biggest
53:12and the smallest lionfish
53:26hundreds gather
53:27to share in the fries
53:30and eat the catch
53:41these derbies serve
53:43to reduce numbers
53:44as well as raising
53:46awareness
53:46of a fish
53:47that threatens
53:48the ocean ecosystems
53:49upon which
53:50the sharks rely
54:07our blue planet
54:08is defined
54:09by its oceans
54:14and if they're to stay
54:16healthy
54:16and productive
54:18we need a healthy population
54:20of sharks
54:24at present
54:25sharks are being killed
54:27faster than they can reproduce
54:29and we're set to lose
54:31some of our most iconic species
54:33in the next 50 years
54:41but across the globe
54:42many people
54:44are working tirelessly
54:45to uncover the secrets
54:47of sharks
54:47in order to save them
54:52people are seeing sharks
54:54in their true light
54:56and starting to appreciate them
54:58for the essential role
54:59they play in our oceans
55:05there is still much work
55:07that needs to be done
55:10but for now
55:11there is hope
55:13for our oceans
55:15are packed
55:15with the ingredients
55:17for recovery
55:22the seas are full
55:24of tiny
55:26microscopic life
55:27just looking for somewhere
55:29to fix
55:31and make home
55:36this is the sapona
55:43it was grounded here
55:46in a hurricane
55:46many decades ago
55:48and ever since
55:49it's become
55:51a living reef
55:54absolutely bursting with life
56:00so many fish
56:04so beautiful
56:11the superstructure
56:13makes a perfect habitat
56:15places for them to hide
56:17from predators
56:19and it's covered
56:21with encrusting
56:22soft corals
56:23and fans
56:29all sorts of animals
56:31take up shelter inside
56:38oh stingray
56:43it's like
56:44swimming through the ribcage
56:48of an almighty whale
56:50lying on the bottom
56:52incredible
56:59this is the basis
57:00of the food chain
57:01upon which
57:02sharks depend
57:14if we protect our seas
57:16and life will bounce back
57:18in our oceans
57:19if we give it the chance
57:27the interconnectedness
57:28of our oceans
57:29and their inhabitants
57:30is intricate
57:31and far-reaching
57:35sharks depend on the creatures
57:36around them
57:37as these creatures
57:39in turn
57:39depend on the sharks
57:43they've been stalking our seas
57:45for at least
57:46400 million years
57:49I hope they've got a few million more
57:51left in them yet
57:54the Bahamas
57:55are at the forefront
57:56of shark research
57:57and conservation
58:00and lessons learnt here
58:01now need to be applied
58:03all across our blue planet
58:09the future of sharks
58:11is in our hands
58:15and it's for us to decide
58:17where this shark's tail
58:19goes next
58:34hunkering down
58:34with Countryfile
58:35on BBC One tonight
58:36the toads are looking
58:37for signs of spring
58:38at seven
58:39aren't we all
58:40if it's a film you're after
58:42BBC Four
58:43has that covered
58:43with a story
58:44of one of the last
58:45great adventurers
58:46the Odyssey
58:47at ten
58:49the Odyssey
58:50of the Odyssey
58:50of the Odyssey
58:51of the Odyssey
58:51of the Odyssey
58:52of the Odyssey
58:52of the Odyssey
58:53of the Odyssey
58:53of the Odyssey
58:53of the Odyssey
58:54of the Odyssey
58:54of the Odyssey
58:55of the Odyssey
58:55of the Odyssey
58:56of the Odyssey
58:57of the Odyssey
58:57of the Odyssey
58:58of the Odyssey
58:58of the Odyssey
58:58of the Odyssey
58:58of the Odyssey