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Open Ocean Jellyfish & Man of War
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0:03
over half of all animals in the open ocean drift in
0:16
currents jellyfish cross entire oceans feeding on whatever happens to tangle with their
0:28
tentacles some can grow to a meter even 2 m across and when by Lucky chance they encounter a patch of sea rich in Plankton their numbers explode
0:49
[Music]
1:14
[Music] it's such a successful strategy the jellies are one one of the most common life forms on the
1:41
planet but among the jellies and looking somewhat like them is a rather more complex and Sinister
1:54
creature the Portuguese man of war
2:03
it floats with the help of a gas filled bladder topped by a vertical membrane with that serving as a sail it maintains a steady course through the waves
2:24
[Music]
2:40
long threads trail behind it some as much as 30 m [Music] long each is armed with many thousands of stinging cells a single tentacle could kill a fish or in rare cases a human
3:05
but among its lethal tentacles LS a Mana War fish that feeds by nibbling
3:18
them once this fish has some resistance to the stings it must still be extremely careful most other fish are not so [Music]
3:41
[Applause] [Music]
3:51
lucky a tentacle has caught this one and reels it in
4:07
it's already
4:13
paralyzed specialized muscular tentacles transfer the victim to others that digest the catch liquefying it with powerful chemicals
4:26
[Applause] eventually all that is left is a scaly
4:44
husk this voracious man of war May collect over a 100 small fish in a day [Music]
5:04
[Music]
5:19
the struggle to survive in our green Seas can have far reaching consequences once a year one particular particular Meadow in Australia is
5:39
transformed around the first full moon of winter an army
5:49
materializes spider crabs
5:59
for the past year they've been feeding in deeper
6:13
waters now they march across the seagrass plains
6:26
[Music]
6:36
hundreds of thousands of [Music]
6:46
them they clamber over one
6:54
another creating great Mounds [Music]
7:03
nearly 100 m
7:08
long they're not seeking mates neither are they laying eggs they have come here in order to
7:20
grow like all crabs their bodies are enclosed in a hard unexpandable shell so to grow they have to break out of
7:42
it and that allows the soft one that has developed beneath to
7:55
expand it will take days for the new shell to Haren
8:12
its legs are so limp that they won't work
8:18
properly the crab is unprotected and in great Danger
8:32
a smooth
8:37
Stingray it's huge about 4 M long it wants a soft freshly melted crab that will be easier to eat
9:10
the crabs try to stick
9:19
together but now disturbed by the ray they're scattering
9:30
a newly molded crab is too weak to keep up with the
9:49
crowd the safest place is right in the middle of the pile that is why they have all assembled here
10:07
there is safety in
10:24
numbers but the vast majority of the crabs Escape and within the next few days they will be ready to return to the depths and resume their lonely wanderings in search of
10:50
food this is no graveyard but the Triumph of 100,000 crabs successfully
11:06
molted a Sally Lightfoot crab one of thousands of shore crabs just waiting for their moment every day they gather on the tropical shores of [Music] Brazil waiting for the tide to go out [Music] which exposes their feeding grounds seaweed covered rocks 100 m from the
11:54
shore getting there is a race against the tide
12:05
they leap from rock to
12:13
[Music]
12:19
[Music] rock these crabs seem to be afraid of the water
12:37
and for good
12:50
reason the Moray eel the chain Mor is a specialist crab Hunter
13:05
its blunt teeth can easily grip and crush a crab's [Music] shell it's the crabb's deadliest
13:21
[Music] enemy but the crabs feeding grounds are still a long way
13:37
off they must Press On
14:05
[Music] halfway but the enemy has other [Music] ideas crossing the
14:25
land to reset the ambush
14:32
to feed the crabs must keep
14:40
going but nowhere is
14:46
safe an octopus also a crab killer
15:16
the crabs make a dash for it
15:45
made
15:50
[Music] it risking life and limb to graze on these seaweed [Music] pastures but in 2 hours time when the tide starts to turn they will have to run the gauntlet all over
16:20
[Music] again in a far corner of Southeast Asia lies the Cor Coral
16:32
triangle a cluster of the richest coral reefs in the [Music] world undersea cities crammed full of
16:52
life as in any crowded Metropolis there is fierce rivalry for space
17:03
for
17:08
food and for a partner but the reef is also a Place full of opportunity [Music]
17:30
a
17:47
cuttlefish it specializes in hunting crabs
17:56
[Music] but a large crab is a dangerous
18:11
Quarry it has powerful
18:17
claws the Cuttlefish however has a remarkable
18:26
Talent its skin contains millions of pigment cells with which it can create everchanging colors and
18:39
[Music] patterns and that apparently hypnotizes the crab
18:51
[Music]
19:10
a cuttlefish may be clever but a shark is bigger and it eats cuttlefish time to disappear [Music]
19:29
[Music]
19:39
back to the hunt a new Target but the same mesmerizing technique
19:55
[Music]
20:03
for those that manage to establish themselves in these bustling undersea cities there can be great
20:14
rewards during the dry season over half a million turns crowed onto this remote ATL in the Indian Ocean
20:30
their chicks are still in their dark juvenile
20:38
plumage they vary in
20:43
[Music] age whilst the more advanced chicks take to the air [Music]
21:00
others aren't quite ready
21:05
[Music] yet those just starting to learn to fly use the shallow Lagoon that occupies the center of the at all as their training ground it's difficult for some of them to stay a loft for long [Applause]
21:50
[Music]
22:00
giant
22:14
treales usually they are solitary Hunters but about 50 of them have come here from neighboring reefs attracted by this abundance of potential prey
22:32
[Applause] the fledglings stay out of the water if they can they even drink on the wing [Music]
22:59
if the chali to catch one now they have to up their [Music]
23:13
game so there is a fish here that amazingly has a brain capable of calculating the air speed altitude and trajectory of a bird
23:56
the time comes when every fledgling has to take to the air and collect food for
24:09
[Music]
24:25
itself their parents lead them to the training grounds
24:36
[Music]
24:58
a
25:11
[Music]
26:03
[Music] if they are to survive they must learn [Music] quickly after a month of practicing over the Lagoon the youngsters start to leave and take their chances out over the Open Sea
26:34
out here on the sand Flats there is safe accommodation for
26:47
some a family of Saddle black clown fish have found an excellent home the tentacles of this carpet nemon can kill but the clown fish are immune to the [Music] poison so they can shelter from [Music] danger in return the fish keep the anemon clean of [Music] debris as with all clownfish the family is ruled by a big female her white face marks her out as the
27:42
boss the Domin of maale has to prove his worth so he works tirelessly removing debris and generally keeping on top of the housework
27:59
[Music]
28:14
his greatest challenge is to find a safe place where the boss can lay her
28:23
eggs but there's nothing solid here for the female to lay them on
28:33
a nearby shell could be the
28:46
solution if only he can move it to the protection of the anemon
28:54
[Music] too
29:03
heavy besides it has a mind of its
29:09
own hermit
29:20
crab but out here twice a day the anemon is swept by tidal currents and they bring in new
29:31
opportunities an old plastic
29:38
bottle perhaps this will
29:47
do not heavy enough
29:55
[Music]
30:02
a coconut [Music] shell it looks just right but it's a long way from home
30:23
[Music]
30:32
and he can't move it by
30:43
[Music] himself so the pair now work together [Music]
31:15
[Music] on
31:26
[Music] a little adjustment to the anemon tentacles in order to clear a space for it and the shell is tucked [Music] in the female lays a safe Nursery at last [Music] he has proved himself worthy to Father her young and he fertilizes [Music] them now he will meticulously tend the eggs [Music]
32:29
keeping them clean and healthy until they hatch in 10 days [Music]
32:46
[Music]
32:54
time the blue shark
33:03
it travels over 8,000 km a year riding on the currents supported by its broad wing-shaped
33:15
fins this one may not have eaten for 2
33:25
months but the currents can carry pring traces of fatty oils from many kilometers away and will lead it to its next [Music]
33:40
meal after days of travel the smell of food gets stronger
34:00
[Music]
34:07
a dead whale recently struck by a
34:13
ship this could be a real Feast but the blue shark must be cautious
34:29
great white sharks 10 times heavier than a blue a highly possessive around a whale carcass
35:09
great whites are eager to feed on energy rich whale blubber which we now know forms a major part of their diet
35:25
[Music] once the great white has had its fill smaller sharks like the blue shark tackle what's left of a
35:45
carcass as the oils from this dead whale spread more widely more and more blue sharks appear
35:58
[Music]
36:13
within days the carcass will be stripped of its
36:25
blubber then no longer longer kept buoyant by its oil it will sink Into the Depths
36:35
below the blue with its reserves of fat replenished can now survive for another 2 months without
36:55
eating but most of the creatures come together for a very different reason to
37:07
breed the giant cuttlefish the largest of all [Music] cuttlefish they live for just one or two years
37:29
now as the Australian summer draws to an end they have one last act
37:39
complete to find a
37:45
mate but there are over 100,000 males competing for the arriving females in this one Bay
38:00
among them a giant a true Goliath he probably weighs about 10
38:09
kilos bands of color sweep across his skin that's how cuttlefish communicate
38:35
this smaller male couldn't possibly take him [Music]
38:48
on beside Goliath and under his protection a female who has just mated with him but other Rivals are still
39:04
interested it seems a small male wouldn't stand a chance the female is now displaying a white stripe along her side nearest Goliath it's a clear signal that she no longer wants to mate with him
39:26
[Music] it's all the encouragement that the little male
39:34
[Music]
39:53
needs he's going to have to use trickery
40:03
[Music]
40:11
he tones down his colors and Tucks in his arms he's just the right size to mimic a female [Music]
40:33
Goliath is deceived the small male now displays a white stripe just like the real female to deter his
40:51
advances he slips beside her and they
41:02
[Music] meet by meting with multiple partners the female ensures the greatest genetic diversity for her
41:23
young the sneaky male leaves his final Act
41:32
[Music] complete so even among giant cuttlefish it seems it's not all about
41:53
size in the underwater forests of Northern Japan the residents of this sunken wreck are waiting for the summer temperatures to reach 16°
42:09
[Music]
42:16
cus that for some is the time for mating
42:32
[Music] a kind of giant Rass called a cobod
42:44
die this is a [Music] male and in female terms he's particularly handsome
43:02
[Music] he's a meter long and weighs 15 [Music] kilos much larger than the dimin [Music] female and he is ready to
43:22
breed he attempts to mate with her and with any of the other dozen or so females that live in his territory whenever he gets the
43:39
[Music]
43:47
chance but females from around 10 years old take little notice of his advances
44:00
[Music]
44:22
this is because when any large female reaches a critical body size she can begin a dramatic
44:47
transformation over just a few months particular enzymes inside her body cease to work and male hormones start to
45:03
circulate as time passes her head expands and her chin gets longer a she has changed into a he
45:27
and with this comes a change in
45:36
temperament the old male who ruled all the females here is challenged to a face
45:50
off the more bulbous the head the more it intimidates an opponent [Music]
46:21
[Music] the territory has a new ruler
46:38
only the largest females transform themselves in this
46:47
way but the change enables them to have more mates so they will have many more offspring carrying their jeans [Music] but a new male can't afford to be complacent inside the body of every codai female there is a new maale in
47:23
waiting and wave power creates towering fortresses like these cliffs in the Arctic home to tens of thousands of breeding
47:37
seabirds the faces of the cliffs are accessible only from the air and have plenty of nooks and crannies for those that can get
47:50
there but to feed seabirds must still Master the ocean World Beyond
48:01
a
48:05
puffin he's a fisherman and a
48:13
father he has a mate for [Music] [Applause] life both share the burden of raising their weak old chick their puffling who needs five square meals a day the parents alternate fishing [Music] trips it's Dad's turn
48:50
[Music] when fish stocks are low puffins must fly as much as 50 km out to sea to reach the good fishing grounds [Music]
49:27
once there they plunge into another
49:38
world good fishing spots are hard to come by and they have company
49:53
gilot like the Puffin their wings are short and good for diving puffins can hold their breath for over a minute and dive as deep as 40
50:11
m a catch
50:32
but it's a long way
50:48
home after an exhausting round trip of almost 100 km this puffins nearly made it but there are pirates on this Coast Arctic skewers
51:11
[Music]
51:30
all around returning parents are being robbed
51:51
[Music]
52:00
the skewers long rback Wings make them faster and more maneuverable [Music]
52:18
[Music]
52:43
puffins must choose their moment wisely
52:56
[Music] a near
53:12
[Music]
53:25
Miss the last desperate burst of speed and it's made it
53:41
[Music]
53:55
[Music] safely home after a 3-hour round [Music] trip where his patient partner is waiting [Music]
54:23
[Music] [Applause] today their puffling will [Music]
54:38
eat but where fish numbers are in Decline many puffins Now find it hard to get enough food for their chicks in the changing Seas of today it can be even harder to be a successful Puffin parent [Music]
55:05
a kilometer from the surface beyond the reach of the
55:14
Sun a giant black void larger than all the rest of the world's habitats combined
55:27
there's life here but not as we know
55:42
it alien-like creatures produce dazzling displays of light
56:00
nearly all animals need to attract mates and repel Predators this language of light is so widespread here that these signals are probably the commonest form of communication on the entire planet and yet we still know little about them
56:34
[Music]
56:46
Hunters illuminate themselves and by doing so attract inquisitive prey
56:55
[Music]
57:04
this is fang tooth it has the largest teeth for its size of any fish there are precious sensors all over its head and body which can detect anything moving in the surrounding water [Music] it's the midnight Zone's most fucious fish but prey used light as a
57:40
distraction a decoy of luminous
57:52
ink down here in this blackness creatures live beyond the normal rules of
58:06
time siphonophores are virtually Eternal they repeatedly clone themselves some eventually growing longer than a blue whale
58:43
down here it
58:53
snows continuous clouds of organic debris drifts slowly down from
59:02
[Music] above this is food and a whole variety of filter feeders depend on it
59:23
[Music] jellyfish and delicate sea [Music]
59:46
cucumbers the 1% of marine snow they miss eventually settles on the sea floor
1:00:02
[Music]
1:00:21
over millions of years it forms a layer of mud up to a kilometer
1:00:30
thick it's an empty plane that covers half the surface of our planet [Music]
1:01:02
the Deep seab bed May at first appear lifeless but it's home to a unique cast of mud [Music] dwellers the sea toad it is an ambush Predator with an enormous mouth and infinite [Music]
1:01:37
patience this fish has been living for so long here that its fins have changed into something more
1:01:49
[Music] useful feet
1:01:55
[Music] they help it shuffle about on the sea
1:02:07
[Music]
1:02:19
Flor the flapjack octopus
1:02:27
it hovers just above the surface of the mud as it delicately sifts through it searching for
1:02:36
worms but it can jet away at the first sign of danger
1:02:52
[Music] in the Gulf of Mexico these eruptions also release a super salty
1:03:18
liquid Brian [Music]
1:03:32
it's heavier than seawat and it accumulates in great pools on the seaf
1:03:42
floor it's difficult to make sense of the
1:03:52
site a lake of concentrated salt water 15 M deep at the bottom of the
1:04:05
[Applause] sea around its margin perhaps even more strangely there is a profusion of
1:04:21
life giant muscles that can live and grow for a century or more pack tightly together dwarfing the shrimps and squat lobsters that feed around them
1:05:00
Cutthroat eels scavengers come to the shores of the Brian Lake in search of something
1:05:15
edible some even Venture into the brine
1:05:44
[Music]
1:05:53
spending too long in it can send an into toxic [Music]
1:06:08
shock it only hope is to rise above it [Music] [Applause]
1:06:26
it manages to
1:06:36
escape others are not so
1:06:45
lucky the brine inals their bodies and the casualties of decades accumulate around the margins
1:07:02
[Music]
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