Original subtitles

The seas of Arabia are alive with carnivores.

Sharks and rays patrol the coral reefs,

hunting down their prey.

Toxic fish disguise themselves

to ambush the unwary.

And bizarre armored predators

devour the vulnerable.

These are the Carnivores of the Coral Garden.

In the remote northwest corner of the Indian Ocean,

the seas around Arabia

are among the richest in the world.

Nowhere is this more evident

than in the coral gardens off the coast of Oman.

Here a rare upwelling of cold water

brings nutrients to the surface

and, with it, an explosion of life.

The Sultanate of Oman

is on the south-eastern coast

of the Arabian Peninsula.

The country has over 200 square miles of coral reef

in its coastal waters.

Unlike some of the world's more famous coral reefs,

Oman's remain largely unexplored.

But spend a day here

and the carnivores will reveal themselves,

each with its own special tactics to survive.

It's dawn.

A top carnivore looks for a place to rest

after a night of hunting.

A zebra shark,

an apex predator in the Gulf of Oman

and a permanent resident of this reef.

Growing up to eight feet,

this solitary shark is no threat to fish or humans...

..but crustaceans and mollusks had better beware.

This carnivore prefers prey that hides in the crevices of the reef at night

and in the sandy sea floor.

Up close, this one reveals

its distinctive spotted skin pattern.

It more closely resembles a leopard than a zebra.

But this is an adult.

The zebra shark begins life with dark stripes

and that's how it gets its name.

As a juvenile grows,

the dark bands gradually morph into small dark blotches on a yellow skin.

It's unusual for an animal to be named for its juvenile markings.

This radical change of pattern is common among carpet sharks,

the order of animals to which the zebra shark belongs.

Fully grown, this adult's tail, or caudal fin,

is almost half the size of its entire body.

It's inefficient for high-speed or long-distance swimming.

But this carnivore doesn't migrate like many other sharks.

It also doesn't need speed to catch its mostly slow-moving prey...

..but it does need agility.

The tail, along with fixed pectoral fins,

enables it to carefully navigate around the reef.

Although solitary by nature,

the zebra shark is rarely alone.

This female has a number of carnivorous freeloaders in tow this morning.

Remora fish often travel with sharks.

They stick close to their host

to feed on its parasites and dead skin.

But this nocturnal hunter will soon take a break.

She'll rest in daylight hours and resume her hunting later.

On the hunt for the same hard-shelled prey...

..is a close relative of the shark,

a stingray.

Also largely nocturnal,

this one cruises menacingly over the sand

looking for a final meal.

Rays are essentially sharks

with flattened bodies and extended tails.

Stingrays have a venomous barb on theirs,

which they can flick over their heads

at a would-be attacker.

A sting can be excruciatingly painful

but human fatalities are extremely rare.

Despite their dangerous reputation,

they rarely use their tails for aggression or defense.

This black-blotched stingray

presses its body flat

and churns up the sand in an undulating movement

to unearth prey hiding under the surface.

It doesn't strike it lucky the first time,

so circles round to try again.

The stingray has large spiracles behind its eyes,

openings through which it draws water in.

It blows it out through its underside gills,

creating turbulence in the sand.

Like the zebra shark,

this bottom-feeder can crush even the most hard-shelled prey.

It has up to 90 rows of teeth in its mouth.

Its journey around the reef looks almost effortless.

Its large, rounded pectoral fins

are fused with its body,

creating a circular disk.

It swims by, creating an undulating wave of movement,

which ripples down its body and propels the stingray forward.

At up to six feet across

and weighing more than 300lbs,

the black-blotched is one of the world's largest species of stingray.

The global population is unknown

but here in Arabian waters,

they're a rare sight.

This one takes a moment to rest.

But it will need to find a more private place to relax

during daylight hours.

Even with a barbed tail,

lying out on an exposed reef can be dangerous.

In a murky reef crevice,

a second stingray settles into its daytime hideaway.

But the stingrays are not the only ones seeking shelter.

A couple of nervous and also nocturnal squirrelfish

are trying to avoid the emerging daytime predators.

The zebra shark also needs a place to rest by day.

Her size means she has little to fear out in the open.

But what's remarkable about this shark

is that she can breathe whilst stationary on the seafloor.

Pelagic sharks, those found in open ocean like great whites,

would die if they stopped swimming.

Their continuous movement forces oxygenated water across their gills,

enabling them to breathe.

But the zebra shark can pump her own water.

Small mouth movements draw it in through her mouth

and push it out through the five gill slits

on either side of her head.

This action is known as "buccal pumping."

Facing into the fast-flowing sea current

makes this even easier.

She props herself up on her pectoral fins

to lift up into the current.

Like the stingray,

she also has spiracles behind her eyes

to help her to breathe by drawing water in.

This adaptation is unique to bottom-dwelling sharks and rays.

Zebra sharks like this exposed part of the reef

with its strong sea currents.

In these Arabian waters, the secretive hunters

are an unusually common sight during daylight.

Above the reef is an archipelago of rocky, uninhabited islands.

These are the Damaniyat Islands.

Lying nine miles off the north coast of Oman,

the islands were the first in the country

to be officially protected in 1996.

They are now one of 14 marine nature reserves in Oman.

From the sea they may look barren and unwelcoming...

..but life does exist here.

Seabirds use these islands to rest on and feed from.

The rocky shores provide homes for crabs.

At certain times of year even sea turtles will nest here.

But it is the fringing coral reefs in the water around the islands

that attract the greatest variety of species.

As the sun rises and the nocturnal hunters wind down,

the daytime carnivores emerge from their night-time hideaways.

The goatfish is one of the busiest in Arabian waters.

This one actively digs for worms, crustaceans

or other small invertebrates it can find.

It uses the long barbels protruding from its chin

to detect prey as it rifles through the sediment.

Its distinctive colored markings give this one its name.

Yellow-striped goatfish.

The goatfish is not alone.

Spinecheeks loiter nearby.

This one is keeping a close eye what the goatfish is unearthing.

It does none of the work

but waits patiently,

ready to reap the rewards of the goatfish's vigorous efforts.

The spinecheek gets its name

from an almost invisible backwards-pointing spine

just behind its eye.

This carnivore is a type of bream

but unlike his more familiar cousin, the sea bream,

which lives in deep water,

the spinecheek prefers these food-rich sandy shallows.

All fish have a lateral line running along each side of their bodies.

In most fish it's not easy to see.

But the patterning of the spinecheek makes it more visible.

Running from nose to tail beneath its distinctive dorsal stripes.

The row of small pores leads to a line of fluid beneath the skin,

which enable the fish to feel changes in water pressure.

This helps them to detect predators and prey...

..and also helps schools of fish to synchronize their movements.

The goatfish rarely gets any "alone time" for hunting.

If it's not the spinecheek then it's a black-spotted butterflyfish.

This butterflyfish lives only in Arabian waters.

It prefers to eat coral

but it's not going to turn down

the chance of a free meal.

At last, the smaller of the two goatfish

strikes it lucky.

It's hit a patch of tasty invertebrates under the sand.

The two tuck in to their well-earned feast,

finally away from the attentions of their lazier followers.

Not all of the coral garden carnivores

are easy to see as they hunt.

Expertly camouflaged somewhere in the middle of the rocks and coral

is one of the cleverest carnivores in the Arabian Seas.

Blending perfectly with its surroundings,

a scorpionfish conceals itself as a piece of coral.

Only the slightest movement

gives this skilled mimic away.

This is a bearded scorpionfish,

a lethal ambush predator and highly toxic.

It lies motionless, waiting to menace passing prey.

If it's quick, it will open its mouth fast enough to create a vacuum

and suck in its prey.

It too is partial to a meal of crustacean

but the small fish hovering overhead

could also be in serious trouble.

An unwary cardinalfish

doesn't see the now perfectly still danger.

Missed!

The scorpionfish concedes defeat and moves on.

Again, barely visible in its new location,

it's a perfect match against the coral.

But this spot is already taken.

A quick pinch from a coral crab sends it on its way.

Maybe it's just not his lucky day.

The glum-looking scorpionfish

bears a strong family resemblance to its more flamboyant cousin,

the equally deadly lionfish.

Better known as the devil firefish in Arabian waters,

this smooth operator drifts in search of its prey.

The lionfish can alter its center of gravity better than most fish

thanks to specialized muscles on both sides of its swim bladder.

It carefully controls its position in the water.

Its feathery fins conceal the movement of the pelvic fin

which can propel it stealthily towards unwary prey.

This is a useful deception for an ambush predator.

Its bright colors and conspicuous patterns

signal danger to predators.

This defensive strategy

is known as aposematic coloration.

The 13 spectacular dorsal spines are highly toxic.

Its fan-like pectoral fins and those by its tail

also pack a deadly punch.

This is not a carnivore to mess with.

The lionfish is usually solitary,

and will fiercely defend its home range against intruders,

especially other lionfish.

But today two swim, apparently amiably, together.

Adults will occasionally come together to combine their hunting skills.

This pair may be working co-operatively to corral small fish.

They spread their pectoral fins wide

as they guide their prey towards the rocks,

where there's no escape.

It doesn't always work.

Ambush is still the lionfish's most effective hunting strategy.

But sometimes catching a meal

is as easy as opening their mouths.

They can create a vacuum and suck up a fish

in a split second.

This one may have swallowed something it doesn't like.

A big gulp

is the fish equivalent of a cough

and bony fish will cough up anything that tastes bad

or they can't digest.

Lionfish more commonly hunt at night,

so these two may have better luck at the end of the day.

Daytime temperatures above the reef

can reach a staggering 116 degrees Fahrenheit.

In the middle of the day,

it's simply too hot to be active on land.

Under the water,

where temperatures are still up to 90 degrees Fahrenheit,

another typically nocturnal carnivore is on the move.

This is a crown of thorns,

an unusually large starfish

that can grow to more than three feet in diameter.

Instead of five radiating arms,

typical of most starfish,

this extraordinary predator can grow a staggering 21.

It's easy to see where the name comes from.

Hundreds of sharp defensive spines cover its entire body,

said to resemble Christ's biblical crown of thorns.

This one is surprisingly agile

as it moves across the seafloor looking for prey.

Starfish typically move at a glacial pace of six inches a minute.

A small shoal of damselfish

and a larger yellowfin grouper

can see the predator as it approaches.

And the crown of thorns can see them.

An eye on the end of each arm can detect shape but no detail.

The fish appear to take flight...

..but they quickly return,

unfazed by the predator in their midst.

The crown of thorns is not interested in them.

It's after the hard coral beneath them.

Its tentacles search for the tiny living coral polyps that cover the surface.

But this bush coral is no longer alive.

The hard skeleton remains have been taken over by algae.

This is now the vegetarian feeding patch of the territorial damselfish.

The hungry crown of thorns must look elsewhere.

Coral reefs are referred to as the gardens of the sea...

..and are often mistaken for plants

but they are in fact tiny carnivorous animals.

They feast on microscopic zooplankton,

which they catch on the ebb and flow of the sea currents.

These coral gardens beneath Oman's Damaniyat Islands

are dominated by huge Acropora corals.

These hard corals are the major reef-building species,

like these spectacular plateaus of staghorn coral.

Branches of beautiful purple sea fans,

close relatives of coral, are also in abundance.

So too are these teddy bear corals,

one of the brightest soft corals on this reef.

Around the world, these tiny carnivores face grave danger.

Warming sea temperatures and pollution

are causing the dramatic collapse of coral reefs.

The water here can reach 90 degrees Fahrenheit,

hotter than Australia's Great Barrier Reef.

But whilst other reefs suffer the devastating effects of coral bleaching,

in part from rising temperatures,

the Damaniyat reefs so far remain less affected.

This may be due to the Indian monsoon

that sweeps up through the Arabian Sea in summer,

bringing with it an upwelling of cold nutrient-rich water

to Oman's southern coast.

Off the north coast,

the Damaniyat Islands are protected from the full force of this cold upwelling

but benefit from pockets of cooler water moving in.

As a result, sea temperatures here

are among the most variable in the world.

Avoiding the constant heat

could be helping to keep the corals alive.

The coral polyps still face danger from predatory carnivores.

A bleached scar can be evidence of death.

The perpetrator is already onto its next victim.

A healthy reef can actually benefit from

some damage to the fast-growing Acropora coral

by giving slower growing species more space to establish,

like this brain coral,

currently occupied by a moray eel.

Come the late afternoon,

the crown of thorns is still on the prowl.

Tiny cardinalfish hitch a ride,

tucked in amongst the hundreds of black toxic spines.

These little nocturnal carnivores

gain sanctuary with their spiked protector

until darkness falls,

when they too will head out to hunt.

As their host travels over the reef,

its long, white tubular feet probe for tasty coral polyps.

If it finds some, it feeds in the most remarkable way.

It's able to push its entire stomach

out through its mouth on its underside

to smother the coral.

Stomach enzymes break down the living coral tissue

into a kind of "soup",

which the crown of thorns then sucks up

as it retracts its stomach back in through its mouth.

This extraordinary tactic

allows it to feast five times faster than other starfish.

Its weaponized arms are prehensile,

meaning they can grasp or hold on to an object.

Within a minute, the carnivore smothers the coral.

Its tiny passengers jump ship

into the equally protective spines of an adjacent sea urchin,

their more common host.

The crown of thorns keeps moving on its destructive coral path.

But this staghorn coral is already fatally damaged.

Crown of thorns often return to the scene of their feasting crimes

to remove any last polyp survivors.

The hunter has already sucked the life out of this coral,

evidenced by the algae and fine mucus now coating the skeletal remains.

The master of coral mimicry,

the bearded scorpionfish,

has found itself a new afternoon dining spot.

Color-matched to the brain coral to the right,

only a flicker of an eye reveals its true identity.

It waits patiently for a nervous shrimp

to make a fatal mistake.

The bearded scorpionfish gets its name from

the leafy tassels beneath its wide, powerful mouth.

Known as cirrus, they extend across the body,

breaking up the hard outline,

allowing it to virtually disappear.

Something catches its eye.

A small goby,

not quite within strike range.

The hunter makes its move.

It lacks the gliding ability of its more elegant relative,

the lionfish.

Without even a basic swim bladder

to control its buoyancy,

it must use its pectoral fins

to stumble across the bumpy reef.

Like its relative and also its land-loving namesake,

this scorpion has a nasty sting.

Venom glands are concealed at the base of these tasseled fins.

Divers beware!

If touched, this one can inflict intense pain

and cause a whole limb to swell in minutes.

The toxic terror becomes stealthier in its approach.

But the wily goby is alert to the danger.

It stays perfectly still to avoid detection.

The scorpionfish doesn't see the immobile goby...

..and misses another opportunity to feed.

The female zebra shark has spent most of the day alone.

By late afternoon she has company.

Nearby, a male is on the move...

..and looks ready for action.

With dusk rapidly approaching,

he may be preparing to hunt.

But this one appears to have something else in mind.

He nibbles the female's tail.

It's the first sign of courtship.

If he's to succeed in his romantic advances,

this male will need to keep a firm grasp of the tail.

To win her over, he must be tenacious.

His love interest won't wait long.

Zebra shark courtship is seldom witnessed in the wild.

But this encounter offers a rare glimpse

into the shark's private life.

This male is smaller than his potential partner.

He's possibly only just reached sexual maturity

and is new to the mating game.

If he's to succeed he will need to be more assertive.

Before mating, an experienced male

will hold his partner either by the tail or pectoral fin

for several minutes.

Then he must twist her onto her back.

But this one hasn't got past first base yet.

At last, he gets the tail.

Now he has to spin her over.

In the end, the young Romeo gives up.

If she's mated in the past, the female may not need him.

Remarkably, zebra sharks

are able to reproduce long after mating takes place,

giving the impression

of nature's own immaculate conception.

But it's not unusual among sharks

for females to store sperm for several years.

As the daylight begins to fade,

other nocturnal carnivores prepare to hunt again.

Two stingrays circle the seafloor.

These are cowtail stingrays.

They rest in twos or threes for protection

but are solitary hunters.

The two don't stay together for long.

Cowtail stingrays have tapering, flag-like tails

and triangular pectoral fins.

The cowtail hunts for crustaceans and mollusks.

This stingray is also partial to a bony fish,

especially those that lie on the seafloor.

A flatfish is a perfect target.

This one is a sole,

a favorite on both human and cowtail menus.

Eyes on the topside of its body keep watch for danger.

It edges itself slowly away from a perceived threat

using its filament fins to push itself across the sand.

By day, the sole either digs itself under the sand to hide...

..or lies perfectly still,

using its expert camouflage

to melt into its surroundings.

This one is eager to escape...

..but is careful to avoid alerting the stingray to its location.

This fish has a sting in its own proverbial tail.

200 glands along its fins

excrete a toxic substance

that acts as a shark and ray repellent.

If the stingray makes contact,

the sole will unleash the chemical,

disrupting the predator's gills, causing it to flee.

But the sole avoids detection this time.

The second stingray lacks the billowing tail flag of its companion,

most likely a casualty of a hammerhead or requiem shark attack.

Some species of stingray can re-grow a lost venomous barb.

The stingray drifts off through shoals of chromis.

These and other diurnal fish

will soon seek shelter within the reef crevices and overhangs

to avoid the other emerging nocturnal predators.

The day is drawing to a close.

Light fades fast beneath the waves.

A solitary lionfish cruises the reef

at the start of its nightly hunt.

Its long toxic fin filaments radiate like streamers

to keep predators at bay.

The reef feels eerily empty

as it swims with purpose over a vast colony of bush coral.

At each crevice,

the lionfish simply watches and waits.

Finally, its patience pays off.

It gets its first meal of the night.

The zebra shark sets off on her own quest for food.

In the dying light she doesn't need to see her prey.

She can smell it.

Up to two thirds of a shark's brain

is made up of smell sensors known as olfactory lobes.

Moving her head as she swims

helps her detect the exact direction of where to find a crab or shrimp.

Tonight she will hunt without company

as she disappears into the darkness,

a magnificent carnivore among the coral garden.