National Geographic: Ocean Drifters (1993)

Curious minds want to know... documentary movie collection.

Moderator: Maskath3

Watch Docus Amazon   Docus Merchandise

Documentary movie collection.
Post Reply

National Geographic: Ocean Drifters (1993)

Post by bunniefuu »

The human mind

has always had a fascination

with worlds beyond our own

Following the stars across the seas,

early explorers

imagined that they might meet

weird creatures in undiscovered lands.

They never guessed

that under their keels,

drifting in the same currents

that carried their ships,

were life forms far stranger

than anything they could imagine.

It's a world where the forces

of pressure and darkness

have given rise to creatures

as different as on another planet.

Their whole existence is shaped

by the great ocean currents,

which sweep them endlessly

around the biggest living space

in the solar system.

At the edge of this alien world,

here in Florida,

one ocean drifter comes

from the beach itself.

It can take these hatchlings three days

to claw their way up

from nests buried two feet deep.

They may look like land animals now,

but sea turtles have evolved

for 80 million years

to be riders of the ocean currents.

These loggerhead turtles,

no larger than a child's hand,

are about to embark on a perilous

As they head down the beach,

they're already reading

the earth's magnetic field

with their internal compass.

Only one hatchling in a thousand

will survive to adulthood

and ride the currents back to

this beach to breed.

It's among the most extraordinary

odysseys in nature.

This is the story of one loggerhead's

journey into the unknown world

of the ocean drifters.

Like a windup toy, the hatchling swims

relentlessly out into the ocean.

The waves tell her which way to go

away from shore and from

predators stalking the shallow water.

Danger causes her to tuck in her limbs

disguising herself as floating debris.

The shark doesn't see her and swims on

As she heads toward the safety

of deep water,

the hatchling joins a rich tide

of other marine creatures.

Every rock and weed is home to

a different species.

Coastal waters are the fertile

breeding ground for the oceans.

Florida may produce five million

loggerhead hatchlings each year.

In some coastal species,

from a single female.

The eggs of this sea urchin

and the smoky clouds of sperm

from a nearby male

swirl together in a fertility dance

on the ocean floor.

Huge quantities of eggs and

larvae produced along the coastline

will be drawn into the ocean currents.

Most will become food

for other marine creatures.

Setting their offspring adrift

might not sound like good

parental care.

But it's a valuable survival mechanism

for many coastal species.

It lets them populate new areas

and encourages the exchange

of genetic material.

All through the night, instinct

drives the loggerhead to push on.

The outpouring of new life

on the continental shelf below her

is just as persistent.

With the bellows like action

of her pleopods,

the spiny lobster sends

It's a reproductive blizzard.

The lobster's larvae have evolved

a flattened shape;

it suits them for the drifting life

as ideally as a snowflake.

After 36 hours of swimming,

the hatchling is growing tired.

In the clear water 30 miles off

the Florida Coast,

she reaches the edge

of the Gulf Stream,

and finds shelter in the drift lines

of sargassum weed.

This plant spends its

whole life floating on the open sea,

held up by small air bladders.

The sargassum provides a haven

in a vast, featureless world.

All kinds of creatures

find harbor here.

For the first time in her life,

the loggerhead can rest.

But the stillness is an illusion.

The winds have piled up the sargassum

weed in drift lines

along the edge of one of the most

powerful currents in the world.

Just beyond,

the Gulf Stream hurtles by.

Viewed from space, the Earth is alive

with clouds caught up in the rhythm

of the tradewinds.

These winds

and the rotation of the planet

generate the great ocean currents.

The loggerhead will be traveling

for years

in a circle of currents called

the North Atlantic gyre.

Her journey starts off Florida

in the warm waters of the Gulf Stream,

which will carry her

north past Cape Cod.

Satellite imagery is teaching us

that the Gulf Stream

is a wild living carousel,

spinning off side currents,

and stirring up a broth of marine life

The edges of currents are the

great way stations of the open sea.

Plant and animal drifters are drawn

into these fronts,

one species making life possible

for another.

For a hungry animal,

it's an oasis in an oceanic desert.

The sargassum becomes a perch

for goose barnacles.

They glean food particles

from the plankton,

the rich soup of plants and animals,

many of them microscopic.

Even sluggish homebodies

can be marvelously adapted for travel

in the larval stage.

The glorious creature drifting

on wing-like lobes is a snail.

Some snail larvae use tentacle

like arms

for feeding and to keep from sinking.

Some may by able to remain

in this stage from months

until they drift to a suitable habitat

Everything is kept lightweight

for easier travel.

Look closely and you can see

the spiral of a transparent shell.

These beautiful drifters move

so gracefully,

you forget that the Gulf Stream is

hurrying them along at 100 miles a day

Microscopic larvae spawned in Florida

could eventually settle

on the shores of Africa.

And the next generation

may ride the currents back.

The ocean drifters have little to eat

except each other

which they do eagerly.

So if the sargassum weed

provides shelter,

it also harbors death

in an astounding diversity of forms,

often wonderfully camouflaged.

The sea horse has evolved

a mild and plant-like demeanor.

But it's still a predator

and keenly watchful.

It drops down to ambush

its planktonic prey.

Then loops itself back

into the sargassum

to avoid being ambushed itself.

The entire food chain is caught up

in this dangerous game

of deception and self-defense.

Small fern-like animals known

as hydroids

colonize the sargassum

and feed on the most minute plankton.

A sea slug grazes in turn on hydroids.

The slug's camouflage doesn't fool

a potential predator.

But the sea slug has armed itself

with chemical defenses from its prey.

The file fish abandons the att*ck.

But another creature's camouflage

will soon bring the fish to a gory end

The drifting weed may look innocuous.

But look again.

A fish hoping to harvest hydroids

from this leafy growth

would find itself staring

into a malignant eye.

Evolution has made

the four-inch long sargassum fish

the big bad wolf

of this floating world.

Its extraordinary camouflage doesn't

just mimic the coloration of the plant

The white spots also mimic

the tube worms

and hydroids that grow on sargassum.

Its pectoral fins have evolved

into prehensile fingers,

the better to creep through

the foliage.

It will eat creatures

almost its own size,

and its victims thrash around

in its gut momentarily before they die

The loggerhead swims directly

under this hidden peril.

But the sargassum fish

lets her pass by.

Hungry dolphin fish

won't be so particular.

These big, fast-moving fish can devour

all life on the weed lines.

The turtle scramble for a hiding place

Now the loggerhead pushes

onto deeper water.

Beyond the sargassum in the open sea,

gelatinous drifters

are the most abundant life form.

They may be the loggerhead's main

source of food for much of her journey

A jellyfish like this

may be more than 95 percent water.

But the thin membrane of

living tissue is still nutritious.

We know almost nothing

about how the turtle

or any other animal survives here.

We act as if this is our planet

and we call it Earth.

But the oceans are so large

and so deep that they constitute

more than 99 percent

of the inhabitable world.

Even for oceanographers,

the open sea is an alien environment,

tantalizing and yet largely unexplored

Each creature in the currents

has its own story to tell,

its own extraordinary adaptations

to life on the open sea.

Humans venturing into these waters

with scuba gear

study only the upper layers

of the ocean.

They stay tethered to a rope,

like astronauts walking in space.

It's a 500 mile swim to shore.

Richard Harbison

and his colleague Larry Madin

are among the few researchers studying

how these ocean drifters behave

in their own environment.

The air tanks limit them

to 25 minutes per dive.

So they get just a glimpse of how

these high sea drifters really live.

Harbison and Madin specialize

in creatures of incredible delicacy

known as jelly plankton.

This underwater world changes

by the hour.

Many species stay away

from the brightly lit surface by day,

so these researchers dive round

the clock.

Under the cover of darkness,

a whole new world of creatures rises

from the depths.

It is the largest animal migration

on the planet,

and it happens every night

in the oceans.

This sea snail

joins a glorious host of species

as they ascend to feed at the surface.

Life as a jelly

is an ingenious adaptation.

There are no hard surfaces

to run into on the open sea,

so these drifters don't need

a sturdy body.

The gelatinous form gives them the

same buoyancy as the water around them

They've evolved for life at sea by

becoming organized seawater themselves

Near the surface, the smaller drifters

feed on minute plant life

that's been growing all day in the sun.

Bigger animals come up to feed on them

The great oceanic food chain

begins here

and everything else depends on it

This weird apparition is a k*lling

machine for small crustaceans.

The writhing arms of this comb jelly

startle its victims,

which flee straight into the wing

like feeding lobes

at either end

and become entangled.

It's easy to become mesmerized

by the delicate structures

of some ghostly creature turning

gently in the currents.

You can see the b*ating of the heart

through the transparent shell.

Its mouth parts

are like an easterlily.

Ocean conditions have reshaped

it beyond all our notions

of what a snail should be.

Look in another direction,

and there's a salp chain grazing

on small plant particles.

This jelly can reproduce

with extraordinary speed

to take immediate advantage

of a new food source.

The salp sprouts new individuals

like a chain of paper dolls.

The gelatinous form makes

for efficient feeding.

It allows this siphonophore

to spin out lengthy tentacles

like fishing lines.

It twitches its crustacean-like lures

to entice its prey.

In the boundless world of mid-ocean,

with the sea bottom miles below

and no other surfaces nearby,

a jelly is the only niche

for other species.

One animal's body can become

the whole world for another.

A crustacean deposits her offspring

on a comb jelly.

As they grow, they devour their host.

Crustacenas eat jellies,

and jellies eat crustaceans.

It's a banquet where it's difficult to

distinguish the guests from the dinner.

The jellies also prey on one another.

The jelly plankton even have

their own great white shark.

The three-inch-long beroe

is a jelly with jawa.

Its mouth is lined with sharp,

tooth-like hooks.

The beroe latches onto its prey

and then expands to engulf it.

This ability to stretch is another

advantage of the gelatinous form.

Though scuba researchers

are limited to working

in the upper layers of the ocean,

with this submersible,

an oceanographer can study

drifting life forms down to 3,000 feet

There the world of the ocean drifters

becomes even more fantastic.

Edith Widder studies creatures living

in the deep sea currents.

Her pilot maneuvers skillfully

as he collects samples

with a battery of scientific equipment

On the way down,

they may be the first humans

to see creatures that have

drifted here for millions of years

endlessly strange and wonderful.

A siphonophore spirals out into

the watery darkness, like a galaxy.

It's maximizing the feeding area

for its fringe of stinging tentacles.

Scientists have only

recently discovered

this football-size comb jelly.

They call it Big Red.

This fish isn't sick.

In these dark unbounded depths,

with no top and no bottom,

everything simply behaves differently.

Like this squid suspended

in the stillness.

Or this squid which has developed

a transparent gelatinous body.

All the rules are different down here.

Researchers freely admit that what they

know about almost any of these animals

is less than a paragraph.

Scientists have given

this newly discovered deep-sea octopus

the nickname Oumbo.

Wider specializes in bioluminescence,

the ability of living creatures

to communicate by producing light.

To study this phenomenon,

she measures what happens

when bioluminescent animals drift

into this screen.

She must shut down her own floodlights

and use special cameras

to see how they respond.

The pitch blackness of deep water

suddenly explodes in a fiery light show

A sea cucumber

looks strange enough just before

it makes contact with the screen.

Then it turns on its own lights,

and rolls off unharmed.

Almost every animal

uses bioluminescence

in the pitch dark of the deep.

Given the abundance

of life in the oceans,

This may be the most common

form of communication on earth.

The clouds of bioluminescence

can be so bright

that they light up the instruments

inside the submersible

If att*cked

some animals try to confuse their

predator with sheer incandescence,

like a flashbulb in the face.

Others illuminate the predator

in the hope that some larger predator

will come along like a cop

and take it away.

Some use light like a lure

to draw their prey close,

or to attract a mate.

In this world of darkness,

the language of light is so important

that a moment's flickering

may determine whether

an animal lives or dies.

But what we know about bioluminescence

is limited by the difficulties

of ocean research.

Even a submersible stays underwater

for only about three hours.

The promise of oceanography

is tantalizing.

Bioluminescent chemicals

are already being used in medicine.

But reaping the potential benefits

is dangerous work.

In many ways, it's like the grand

adventure of space travel.

But we've mapped the barren surface

of Venus in far more detail

than our own deep ocean floor.

Is it worth exploring the depths

of this planet?

In one area the size

of a small living room,

deep sea researchers recently

discovered 460 new species.

Who knows what secrets

we have yet to discover in the oceans?

Even back on the surface,

the limits of our knowledge can be

painfully apparent.

In the complex ecosystem

at the very skin of the ocean,

a whole other world of creatures

lives both in and out of the water.

As it moves, the stinging tentacles

of the Portuguese man o' w*r

stream out to gather food.

By raising its gas-filled sail,

the man o' w*r can travel

at varying angles to the wind.

It's an elegant system

for dispersing animals

not just where the current takes them,

but across the face of the ocean.

Nothing about the man o' w*r is simple

It's neither an individual animal,

nor a colony, but something in between

Joined together under the gas bladder

is a kind of cooperative assembly

of stomachs,

tentacles, and reproductive organs.

Other species add to the complexity.

One fish, called nomeus,

hides out among the deadly veil

of tentacles.

The man o' w*r toxin is

more potent than the cobra's.

But perhaps because

of a protective mucus layer

or greater immune resistance,

nomeus can dine unharmed

on the man o' w*r itself.

Other fish aren't so lucky.

The man o' w*r can stretch

its tentacles out more than 50 feet,

and each tentacle is studded

with batteries of stinging cells.

Nomeus may help out the man o' w*r by

herding these fish toward their death.

Triggered by the fish,

the stinging cells fire slender

threads lines with barbs.

The victim is lassoed, hog-tied,

and injected with paralyzing poison.

Then the digestive organs move in.

Like some monstrous lifeform,

they wriggle and twist

as they fasten their flexible mouths

onto the victim.

Gradually, they engulf the fish

and dissolve its flesh.

After half a year,

the young loggerheads odyssey

has taken her to mid-ocean.

But she still has a lot to learn.

All the activity around

the man o' w*r catches her eye.

She just wants to grab

a few fishy tidbits

and doesn't seem to notice

the nasty business overhead.

For a moment, the turtle looks like

a puppet on a deadly set of strings.

But it's the man o' w*r

that's in danger.

The turtle turns her hungry eye

on this intriguing new possibility.

People talk about the first

brave human who ate an oyster.

But what a tangled and spicy meal

the man o' w*r must make.

The turtle's skin may be too thick

for the stingers to penetrate.

But no one knows what protects

the turtle's eyes and mouth.

The loggerhead soon pushes on

in search of a meal

that's not quite so challenging.

One of the strangest inhabitants

of the harsh world

between air and water is the drifting

nudibranch named glaucus.

This upside-down sea slug swallows air

bubbles to hold itself at the surface.

With its pointy appendages,

it latches onto anything

it's lucky enough to bump into.

But what it's really after are

the deadly tentacles of the man o' w*r

It coats its mouthparts

with a mucus layer to protect itself.

The smaller less powerful

stinging cells get digested.

But the most virulent stingers

remain intact.

Amazingly, they pass directly

to the nudibranch's extremities

and it uses them for its own defense.

But these surface drifters

must face adversaries even more

formidable than each other.

A storm is brooding up

across the water.

It's a reminder of how unstable life

must be on the very face of the ocean.

One moment these creatures are

being scorched by sun and wind,

and the next they're tumbling

in storm-tossed waves.

As the storm passes,

they get pelted by icy rain

and have to endure the dilution

of their salty home.

Yet the animals living in

the ever-changing surface

can seem so delicate.

This drifting snail

builds a fragile home of air bubbles

sealed in an envelope of mucus

then hangs on for dear life.

If it lets go,

it'll sink into the abyss.

The raft is also holding up

the snail's offspring,

in these egg capsules.

It's a cradle at the top

of a hostile world.

When it's done laying eggs,

the snail builds a new raft for itself

and cuts its 50,000 offspring adrift.

Natural debris also drifts

in the surface currents.

It's always been a means of dispersal

for some plants.

A coconut from the Caribbean

may ride the Atlantic

currents thousands of miles

to take root on some distant shore.

Fish are drawn to this kind

of flotsam for shelter.

A drifting crate can turn

into a small ecosystem,

Where fish lay eggs

or find their food.

But the little things

we throw away add up,

and the supply of garbage begins

to seem endless.

One study estimated that

was being heaved overboard

by ocean-going vessels alone

A recent treaty now regulates

the practice,

but it's rarely enforced.

Whatever goes into the ocean

gets drawn into the currents,

and it builds up in the very places

where marine life is richest.

Animals encrusted on debris may rouse

the loggerhead's hunger and curiosity.

For her, drifting objects have always

been a natural food source.

Until recently, a loggerhead could safely

eat almost anything she came across.

Nothing in her evolution

has prepared her

for this wealth of deadly new choices.

To her, it makes as much sense to pick

at the festive remnants of a balloon

as at a man o' w*r.

Fragments like these

can choke turtles to death.

Plastic blocks their digestive tracts

and causes starvation.

This time, she's unable to

tear off a bite.

But she'll face many more

opportunities as she swims on.

Almost every dead turtle found

has plastic in its gut.

Millions of seabirds also die

each year because of garbage

like this gannet tangled up in debris

absent-mindedly discarded

by sportfishermen.

Commercial fishermen lose thousands

of miles of net each year,

which spread out all across

the oceans like a deadly web.

There may be no way for the loggerhead

to learn about these new perils

until it's too late.

The turtle has survived her first year

But in the long seasons before she

circles home to Florida to lay her eggs

a more sinister peril may thr*aten her

Everything out here

is absorbing a swelling tide

of chemical wastes

even the plankton.

Though they may seem insignificant,

the lifeforms here are important

to cloud formation.

They even help regulate

the global climate.

These microscopic plants and animals

have always struggled against

enormous odds to reach maturity

Now they must also absorb heavy metals

sewage, pesticides and petrochemicals.

Plankton is the base of the food chain

and every marine animal depends on it.

If our carelessness disrupts this vast

drifting tide of life,

will it imperil the entire ocean?

Will it affect the food we eat

and the very air we breathe?

No one has yet spent

enough time traveling

in the loggerhead's world to find out.

It may be that we humans

will always find it easier to turn our

imaginations away from the oceans

and out to other worlds

But as we peer up at the stars,

we should keep one truth in mind

All the alien life forms we know

and perhaps all we ever will know

are here adrift on planet Earth.
Post Reply