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It's been labeled
the most exotic island chain in the world.

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Pristine sands, azure blue seas

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and colorful reefs make Zanzibar

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a much loved holiday destination.

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For centuries,
the lure of ivory, spices and gold,

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has attracted empire builders
from across the globe.

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But people aren't alone
in their quest to set up home here.

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Bizarre creatures, many of enormous size,

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run wild throughout the archipelago.

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And marine giants
patrol the island shores.

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Zanzibar is an untamed wilderness.

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Zanzibar is a land of giants.

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Lying 40 km
off the east coast of Tanzania in Africa,

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the Zanzibar archipelago

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is dominated by two islands,

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Unguja and Pemba.

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Unguja is the larger of the two,

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measuring just 100 km long by 30 wide.

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Around 130,000 years ago,

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the Indian Ocean sea levels began to drop.

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Enormous fossilized coral reefs
were revealed,

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giving birth to Zanzibar,

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and the many smaller islands
surrounding its coast.

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Some creatures began colonizing the island
from day one,

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but along with other primates,

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people set up home here more recently.

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2,000 years ago
settlers arrived along Zanzibar's shores,

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living simple lives governed by the tides.

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Ever since,
the islands have been a trade hub

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between mainland Africa and Asia,

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and the population
has risen to around one million.

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But Zanzibar still has a wild side.

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And as the tides come and go,

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the island's giant creatures
reveal themselves.

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Nothing looks more tranquil,

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than warm tropical waves
lapping over a white, sandy shore.

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However, on Zanzibar's beaches,

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there's far more than meets the eye.

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Some of the island's earliest colonizers
came ashore in search of food,

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long before the arrival of man.

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And they never left.

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At low tide, shore-dwelling crabs

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have important jobs to do.

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Excavating and maintaining burrows

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burns lots of energy.

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Algae and fungu scraped off
filtered sand particles

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forms the bulk of this crab's diet.

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Feeding is a production line process

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leaving sand pallets
dotted along the shore.

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At low tide, black herons

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are also on the lookout for a meal.

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Although the crabs take cover...

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This bird has bigger fish to fry.

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For one species, mealtimes prove
a little more challenging than to others.

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Adult male fiddler crabs
have an over-sized claw.

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It's the violin-playing motion they make
while eating that has given rise to their name.

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Female fiddler crabs
are better balanced than males

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and cause quite a stir
whenever they venture among the boys.

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This frantic waving is all about
catching the eye of a passing lady.

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The faster the rhythm,
the better the chance of being noticed

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and outdoing the competition.

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Females prefer fast wavers

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and this male has struck the right chord

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as his conquest enters his burrow.

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Not all mating is a private affair.

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Some females prefer using
the safety of their own burrows

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to incubate their eggs.

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For male fiddler crabs, size also matters
when it comes to protecting territory.

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Shows of strength like these
deter neighbors from cramping their style

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and also keep potential squatters at bay.

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As the new tide approaches, it's a scramble
to retreat to saftey underground.

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Those who've wandered too far from their burrows
muscle-in on someone else's hard-earned home.

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The turning of Zanzibar's tides
governs the lives of many creatures.

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But certain life forms
have set up permanent home on dry land.

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At just a kilometer long,
and 300 meters wide,

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Zanzibar's Chumbe Island
reveals the fossilized coral

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that forms the region's bedrock.

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Devoid of soil, Chumbe's forest is home

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to a highly-specialized plant community

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that survives without any groundwater.

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Giant roots spread out in all directions

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and smaller species
cling to any surface they can.

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Many plants and trees
get their water from the humid air.

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Others like the baobab stockpile reserve

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during the rainy season.

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These are the green giants
within this forest.

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Lining the island's shore
is another tall tree.

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Although these coconut palms
fall short on girth,

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at 30 meters tall,
they match the baobab for height.

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This slender giant is key
to the existence of a colossus creature

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that thrives on the flesh of its seeds.

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As night draws in,

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the world's biggest creepy crawly
reveals itself.

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Weighing over 4 kg,

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with a leg span up to a meter,

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the coconut crab is the world's largest
land-living invertebrate.

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It's actually a giant hermit crab,

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and while it's young, it carries another creature's
abandoned shell on its back for protection.

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Fully grown, it develops a tough outer skin.

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It stays hidden during the day
to reduce water loss from heat.

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But at night, this solitary stalker

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heads off in search of its favorite food.

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Unlike most of its relatives,

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the coconut crab can't survive in water.

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It would drown if submerged.

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Its gills have evolved to work like lungs

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although they need to be kept moist
in order to function.

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Its antenna have also evolved,

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enabling it to pick up airborne scents

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the same way insects do.

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This forest forager, along with others,

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is on to something.

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Also known as the robber crab
or palm thief,

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coconut crabs are great climbers.

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They can't cut down coconuts
by themselves,

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however fallen fruits
are quickly seized upon.

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Although the surrounding sea
is a no-go zone

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for these land-based giants,

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it wasn't always that way.

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They started life in the water.

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A female coconut crab
makes her way to the shore.

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She's been carrying a batch of eggs

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glued to her abdomen for two months.

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At high tide,
they're ready to be released.

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On contact with water,
the eggs hatch immediately.

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The juvenile giants
eventually make their way ashore.

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They live a hermit's life before becoming
permanent dry-land residents.

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Giants don't just live
above Zanzibar's island shores.

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Beneath the surface
of the surrounding seas,

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lie some of the biggest of all.

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This coral reef is a living seascape

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made up on millions
of tiny plant-like animals

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known as coral polyps.

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Together, they act
as a single super-sized organism.

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Secreting calcium carbonate
from their base,

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the polyps form
complex and striking sculptures.

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Colonies grow over thousands of years,

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eventually joining other communities
to become a reef.

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Some stretch 90 km across the ocean floor

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and have been growing
for over 50 million years.

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Zanzibar hosts some of the most
spectacular coral gardens in the world,

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and over 90%
of East Africa's hard coral species

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are found here.

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These rainforests of the sea

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are at the heart
of an entire underwater ecosystem.

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Anemones, sea cucumbers, eels,

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and an array of tropical fish,

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make this underwater Eden
their permanent home.

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Further along the reef
looms another giant.

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Of the 400 or so species of ray,

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the manta is the largest.

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These alien-looking creatures

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can grow up to an incredible
seven meters across

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and weigh as much as two tons.

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They lead solitary lives

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and only come together in large numbers

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under certain conditions.

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These manta rays have traveled far
to this section of reef for a special service.

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This cleaning station
provides the opportunity

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for a good once-over
from attentive cleaner fish.

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Flashes of blue and yellow
advertise their presence.

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The clients happily flood in.

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But before the manta rays
take up this service,

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they need to form a queue.

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Individuals size one another up

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by swimming parallel to the reef.

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Once a heirarchy is established,

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they take turns swooping into the station.

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Each species of cleaner fish

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nibbles a different section
to reduce competition.

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This mutually beneficial relationship

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provides the fish
with a steady supply of food

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and ensures the manta's skin

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is free of dead cells and parasites.

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Cleaning sessions
can last up to three hours,

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and once thoroughly scrubbed,

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the manta rays head back into the deep.

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Unlike many of their shark cousins,

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these graceful giants
pose no threat to other fish.

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Manta rays are filter feeders,

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and when plankton blooms,

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everyone joins the feeding frenzy.

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Filtering large volumes of water

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they funnel the miniature prey
into their gaping mouths.

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A single manta can sieve
up to 17 kilos of plankton a day.

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Barrel rolling is a quick way of returning
to a particularly dense patch of food.

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As more manta join the feeding frenzy,

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they're suddenly eclipsed
by one of Zanzibar's greatest oceanic giants.

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Whale sharks can grow to over 20 meters

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and weigh up to 34 tons.

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That's more than five African elephants.

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They are by far
the largest fish in the world.

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Dwarfing everything in their wake,

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they survive on some
of the smallest organisms in the ocean.

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They can sift
over 6,000 liters of water an hour.

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Fine filters, also known as gill rakers,

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trap any organism
over two millimeters wide.

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Most species of shark wave their tales

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to propel themselves.

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However whale sharks are unique

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in moving their entire bodies
from side to side.

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They remain close to the surface

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and their top speed
is a modest five kilometers per hour.

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It isn't just giants that are attracted

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to these plankton blooms.

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Smaller fish also move in to feed.

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But dining with this particular giant
has its downside.

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These fishermen have just received
a precious sign.

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Knowing where and when
to cast their nets

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is the key to a good catch.

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The whale shark's tale
act as a valuable time-to-go-fishing flag.

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This small dugout canoe makes light work
of catching up with the shark.

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Their efforts pay off.

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It would normally take a whole day
to land a haul of this size.

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Guided by their giant neighbor,

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the fishermen's nets are soon full.

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As aquatic giants patrol the shores,

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on one island, a unique species of primate

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has taken refuge in the trees.

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Unlike most in Zanzibar's archipelago,

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Pemba Island is formed from a true landmass

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rather than coral reefs and sand banks.

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Lying 40 km north of Unguja,

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rolling hills and forested valleys

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have earned Pemba another name,
Green Island.

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The region's vast number of trees

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are home to one of the rarest primates
in the world.

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Isolated from mainland Africa
for over 10,000 years,

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the Zanzibar red colobus monkey

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has evolved to become a distinct species.

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Its color and some of its habits are unique.

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Feeding is a group activity
that begins in the early morning.

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Colobus are leaf eaters.

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Leaves are highly nutritious,

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but most animals
are unable to digest the cellulose

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that makes up plant cell walls.

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Colobus monkeys have a solution.

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They have a four-chambered stomach,

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like many hooved animals,

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which enables bacteria to ferment

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and break down what they eat.

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After an hour or so's munching,
it's time to rest.

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Their peculiar digestive system

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leads to long periods of inactivity.

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Up to 70% of the time, they're awake.

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But not all members of this troop
are sleepy.

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Unlike most other monkeys,

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young red colobus continue suckling

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for around 18 months.

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Energy from their mother's milk
is quickly converted.

251
00:27:57,273 --> 00:27:59,897
And while the grownups take a nap,

252
00:28:00,057 --> 00:28:03,235
the youngsters decided it's time to play.

253
00:28:11,625 --> 00:28:13,577
For an adult red colobus monkey,

254
00:28:13,737 --> 00:28:17,155
grabbing a peaceful 40 winks
is easier said than done.

255
00:28:26,361 --> 00:28:29,640
Alongside the annoying antics
of the troop's teenagers...

256
00:28:31,785 --> 00:28:34,217
The process of digesting
large volumes of leaves

257
00:28:34,377 --> 00:28:36,691
creates an inevitable byproduct.

258
00:28:48,729 --> 00:28:50,873
Methane and carbon dioxide

259
00:28:51,033 --> 00:28:55,068
are two gases these youngsters
will just have to learn to live with.

260
00:29:13,707 --> 00:29:18,342
Zanzibar's red colobus
are also fond of unripe berries and seeds.

261
00:29:21,387 --> 00:29:23,051
Unlike many primates,

262
00:29:23,211 --> 00:29:27,768
their stomachs can't digest
the sugars contained in the more mature fruit.

263
00:29:41,403 --> 00:29:43,067
Here on Pemba Island

264
00:29:43,227 --> 00:29:46,405
is a giant creature
that does have a sweet tooth.

265
00:29:50,187 --> 00:29:54,419
The Pemba flying fox
is the largest bat in the world.

266
00:29:58,011 --> 00:30:00,949
It has a wingspan in excess
of a meter-and-a-half.

267
00:30:06,027 --> 00:30:09,899
Most other bats use acute hearing
to capture insects,

268
00:30:10,059 --> 00:30:13,019
but flying foxes rely on large eyes

269
00:30:13,179 --> 00:30:15,493
to track down their meals.

270
00:30:19,755 --> 00:30:22,187
Blossom, nectar and ripe fuit

271
00:30:22,347 --> 00:30:25,189
make up the majority
of their vegetarian diet.

272
00:30:29,067 --> 00:30:31,979
These mega-bats have excellent vision

273
00:30:32,139 --> 00:30:34,165
and good hearing.

274
00:30:37,083 --> 00:30:39,275
They're also very vocal,

275
00:30:39,435 --> 00:30:42,891
especially when neighbors
get a little too close.

276
00:30:54,929 --> 00:30:57,265
Living in large groups of up to 850

277
00:30:57,425 --> 00:30:59,425
has its downside.

278
00:30:59,585 --> 00:31:02,427
Especially when all you want to do is sleep.

279
00:31:08,369 --> 00:31:10,033
But as night draws in,

280
00:31:10,193 --> 00:31:13,153
the inconvenience of sharing a tree
with so many

281
00:31:13,313 --> 00:31:15,243
reaps its reward.

282
00:31:18,737 --> 00:31:21,627
Flying foxes split up in search of food.

283
00:31:26,513 --> 00:31:28,417
When they return to the roost,

284
00:31:28,577 --> 00:31:31,585
different scents indicating
which trees are in fruit

285
00:31:31,745 --> 00:31:34,203
are shared among the entire group.

286
00:31:39,569 --> 00:31:42,689
Individuals now know
where to forage the following night.

287
00:31:52,595 --> 00:31:54,403
While Pemba Island's flying foxes

288
00:31:54,563 --> 00:31:57,715
help pollinate plants and disperse seeds,

289
00:31:57,875 --> 00:32:01,293
another mammal
causes nothing but trouble.

290
00:32:09,731 --> 00:32:12,211
Vervets are medium-sized monkeys

291
00:32:12,371 --> 00:32:15,069
that hang around in troops of up to 50.

292
00:32:18,419 --> 00:32:20,179
Unlike the island's red colobus

293
00:32:20,339 --> 00:32:22,435
that suckle for well over a year,

294
00:32:22,595 --> 00:32:25,869
vervet youngsters
nurse for approximately four months.

295
00:32:32,483 --> 00:32:36,248
The school of hard knocks
starts early in vervet society,

296
00:32:36,419 --> 00:32:39,021
and this troop are up to no good.

297
00:33:01,139 --> 00:33:02,947
Fruits, berries and leaves

298
00:33:03,107 --> 00:33:06,307
make up a large part
of this monkey's diet.

299
00:33:06,467 --> 00:33:09,693
But one of their favorites fruits is cassava.

300
00:33:18,803 --> 00:33:23,107
This starchy, tuberous root
is full of carbohydrates,

301
00:33:23,267 --> 00:33:26,349
and is one of the most
drought-tolerant crops on the planet.

302
00:33:31,427 --> 00:33:35,203
After rice, cassava is
the second-most important food crop

303
00:33:35,363 --> 00:33:37,581
throughout Zanzibar.

304
00:33:54,899 --> 00:33:56,755
Protecting their precious fields

305
00:33:56,915 --> 00:33:59,565
is a constant battle for Pemba's farmers.

306
00:34:08,291 --> 00:34:10,531
The vervets realize they've been spotted

307
00:34:10,691 --> 00:34:12,861
and scramble back to the trees.

308
00:34:23,843 --> 00:34:25,699
The farmer's catapults and sticks

309
00:34:25,859 --> 00:34:28,317
act only as a temporary deterrent.

310
00:34:32,531 --> 00:34:35,600
The vervets don't just pose a problem
to people's livelihoods.

311
00:34:36,611 --> 00:34:41,080
One of the island's animal residents
often falls foul to this monkey's antics.

312
00:34:44,819 --> 00:34:48,640
They've dislodged a mother
and baby flying fox from their tree.

313
00:34:52,493 --> 00:34:54,493
Unable to take off from the ground,

314
00:34:54,653 --> 00:34:57,495
the farmers realize the pair need help.

315
00:35:18,221 --> 00:35:20,365
20 years ago, these giant bats

316
00:35:20,525 --> 00:35:22,765
were virtually hunted to extinction

317
00:35:22,925 --> 00:35:25,095
by local islanders.

318
00:35:28,589 --> 00:35:30,711
Today the species is protected.

319
00:35:31,853 --> 00:35:36,800
The Pemba people realize the important role
the bats play in dispersing pollen and seeds.

320
00:35:37,949 --> 00:35:41,031
They're vital
for keeping the region's forest alive.

321
00:35:53,933 --> 00:35:56,941
On Unguja Island, the tide retreats

322
00:35:57,101 --> 00:35:59,703
and local women go to work.

323
00:36:06,749 --> 00:36:10,712
The Nungwi people have hunted
along these shores for centuries.

324
00:36:15,197 --> 00:36:19,095
They're searching for food,
but in particular, octopus.

325
00:36:26,909 --> 00:36:29,581
Every nook and cranny is checked.

326
00:36:29,741 --> 00:36:32,007
The octopus could be hiding anywhere.

327
00:36:43,891 --> 00:36:46,733
Finally, one of the group may be in luck.

328
00:36:53,347 --> 00:36:55,443
Finding an octopus is one thing.

329
00:36:55,603 --> 00:36:58,205
Coaxing it out of its lair is another.

330
00:37:08,851 --> 00:37:11,475
Collecting octopus
is a way of life for the Nungwi,

331
00:37:11,635 --> 00:37:14,217
as well as putting food on the table.

332
00:37:14,377 --> 00:37:17,219
Any excess catch
is sold to the local market.

333
00:37:23,497 --> 00:37:27,160
Over-hunting is avoided
by only fishing on the last days of the month,

334
00:37:27,337 --> 00:37:29,795
when the tides are at their lowest.

335
00:37:36,265 --> 00:37:39,683
Zanzibar's tides also support
another local business.

336
00:37:45,049 --> 00:37:47,145
Seaweed is used all over the world

337
00:37:47,305 --> 00:37:49,353
as an ingredient for fertilizers,

338
00:37:49,513 --> 00:37:52,163
cosmetics, even cheese.

339
00:37:58,633 --> 00:38:00,969
Pegs, set 10 meters apart

340
00:38:01,129 --> 00:38:03,561
are joined by a network of ropes

341
00:38:03,721 --> 00:38:06,659
to which plant cuttings are tied.

342
00:38:14,137 --> 00:38:18,009
The seaweed remains submerged
in these inter-tidal lagoons

343
00:38:18,169 --> 00:38:20,867
and takes around two months to grow.

344
00:38:32,137 --> 00:38:35,363
Once harvested,
the plants are hung out to dry in the sun.

345
00:38:41,209 --> 00:38:43,449
Zanzibar exports around 700,000 tons

346
00:38:43,609 --> 00:38:45,801
of seaweed every year.

347
00:38:45,961 --> 00:38:49,187
And most famous make around $40 a month.

348
00:39:00,025 --> 00:39:02,361
Although seaweed
is highly prized by humans,

349
00:39:02,521 --> 00:39:04,761
one of Zanzibar's aquatic creatures

350
00:39:04,921 --> 00:39:07,139
is especially fond of it as well.

351
00:39:12,793 --> 00:39:16,089
At high tide,
green turtles enter the lagoons

352
00:39:16,249 --> 00:39:18,899
to feast on any floating fare.

353
00:39:24,169 --> 00:39:26,505
When young, these amphibious reptiles

354
00:39:26,665 --> 00:39:29,987
feed on jellyfish, shrimps, the small fish.

355
00:39:33,961 --> 00:39:35,529
Measuring over a meter long

356
00:39:35,689 --> 00:39:38,697
and tipping the scales
at around 200 kilograms,

357
00:39:38,857 --> 00:39:40,665
it's only during adulthood

358
00:39:40,825 --> 00:39:43,955
that these green giants
become strictly vegetarian.

359
00:39:49,369 --> 00:39:53,440
Apart from when they're nesting,
green turtles rarely come ashore.

360
00:39:56,329 --> 00:39:58,521
However one of their giant relatives

361
00:39:58,681 --> 00:40:01,977
has set up permanent home
on Zanzibar's Changuu Island,

362
00:40:02,137 --> 00:40:05,315
less than five kilometers away.

363
00:40:12,553 --> 00:40:14,553
At over 250 kilograms in weight

364
00:40:14,713 --> 00:40:18,153
and with a shell length
approaching one-and-a-half meters,

365
00:40:18,313 --> 00:40:22,259
the aldabra is one of then largest tortoises
in the world.

366
00:40:29,497 --> 00:40:32,313
It's one of the longest-lived animals too.

367
00:40:32,473 --> 00:40:34,931
Some live for over 200 years.

368
00:40:39,529 --> 00:40:43,187
Giant tortoises feed mainly
on grasses and woody plants.

369
00:40:44,089 --> 00:40:47,880
Whenever these aren't within reach,
dried leaves will do.

370
00:40:54,265 --> 00:40:57,299
This crunchy meal
contains very little moisture.

371
00:40:58,297 --> 00:41:03,630
So aldabra tortoises draw on a special method
to re-hydrate their enormous frames.

372
00:41:08,281 --> 00:41:10,329
The fat stored beneath their shells

373
00:41:10,489 --> 00:41:12,563
can be converted to water.

374
00:41:17,305 --> 00:41:21,857
Burning these reserves releases fluid
during the hottest parts of the day

375
00:41:22,009 --> 00:41:24,275
and prevents them becoming dehydrated.

376
00:41:29,497 --> 00:41:33,360
Changuu's giant tortoises
can survive without water for long periods.

377
00:41:34,729 --> 00:41:36,729
But for creatures less fortunate,

378
00:41:36,889 --> 00:41:39,827
another location
provides a permanent wetland.

379
00:41:50,041 --> 00:41:51,945
On Zanzibar's Unguja Island,

380
00:41:52,105 --> 00:41:55,235
the shoreline boundary
isn't clearly defined.

381
00:41:59,641 --> 00:42:01,977
Small estuaries venture into forests,

382
00:42:02,137 --> 00:42:05,747
forming a unique relationship
between land and sea.

383
00:42:12,697 --> 00:42:16,249
Mangroves thrive in saline coastal habitats.

384
00:42:23,324 --> 00:42:27,422
A complex system of aerial roots
enables the intake of oxygen

385
00:42:27,596 --> 00:42:29,932
and traps organic debris

386
00:42:30,092 --> 00:42:33,404
that would otherwise be washed out to sea.

387
00:42:50,444 --> 00:42:53,212
These tidal swamps
provide a breeding ground

388
00:42:53,372 --> 00:42:56,982
and nursery for several species
of fish and invertebrates.

389
00:43:17,735 --> 00:43:21,840
Many of these will head out into
the surrounding reefs and seabeds when adults.

390
00:43:28,151 --> 00:43:32,613
Some species of mangrove have developed
a unique method of reproducing.

391
00:43:36,935 --> 00:43:40,663
The seeds germinate
and become fully-fledged seedlings

392
00:43:40,823 --> 00:43:43,473
while attached to the mother plant.

393
00:43:49,271 --> 00:43:53,842
These pods are then released,
allowing them to immediately take root.

394
00:43:56,327 --> 00:43:59,553
Or they can remain dormant
to float further afield.

395
00:44:11,255 --> 00:44:14,988
Adjoining the mangrove,
is the largest reserve of mature woodland

396
00:44:15,143 --> 00:44:17,793
in the entire archipelago.

397
00:44:39,143 --> 00:44:43,015
Living fossils, like this cycad tree,

398
00:44:43,175 --> 00:44:46,593
have remained unchanged
for millions of years,

399
00:44:47,543 --> 00:44:50,385
a lineage stretching back
before the dinosaurs.

400
00:44:57,677 --> 00:44:59,389
Similar to pine trees,

401
00:44:59,549 --> 00:45:02,199
this species doesn't produce any flowers.

402
00:45:04,493 --> 00:45:06,733
However, unlike their relatives,

403
00:45:06,893 --> 00:45:11,079
each cycad tree produces
only male or female seed cones.

404
00:45:15,197 --> 00:45:17,725
These colorful structures
can be up to a meter long

405
00:45:17,885 --> 00:45:20,247
and weigh over 30 kilos.

406
00:45:28,925 --> 00:45:31,405
It's no wonder, even herb-loving dinosaurs

407
00:45:31,565 --> 00:45:33,831
became such giants too.

408
00:45:39,149 --> 00:45:42,519
Jozani Forest lies at the heart of the island.

409
00:45:44,717 --> 00:45:48,349
Alongside the vast array
of birds, insects and reptiles,

410
00:45:48,509 --> 00:45:51,255
it's home to two species of primate.

411
00:45:54,317 --> 00:45:57,399
Sykes monkeys eat virtually anything,

412
00:45:58,637 --> 00:46:01,117
leaves, ripe fruits and flowers,

413
00:46:01,277 --> 00:46:04,503
Insects, and even small vertebrates.

414
00:46:13,345 --> 00:46:16,906
However, not every prey
makes an easy picking.

415
00:46:20,496 --> 00:46:22,736
Zanzibar's giant carpenter ants

416
00:46:22,896 --> 00:46:25,018
also have a giant bite.

417
00:46:30,624 --> 00:46:32,768
At around two centimeters in length,

418
00:46:32,928 --> 00:46:35,818
they put up a strong defensive fight.

419
00:46:41,376 --> 00:46:45,430
This monkey soon realizes
it's bitten off more than it can chew.

420
00:46:49,200 --> 00:46:52,064
Jozani's other primate,
the red colobus monkey

421
00:46:52,224 --> 00:46:54,346
is a strict vegetarian.

422
00:46:56,880 --> 00:47:00,080
It's identical
to the species found on Pemba Island,

423
00:47:00,240 --> 00:47:02,000
except this particular population

424
00:47:02,160 --> 00:47:03,920
has come up with a unique solution

425
00:47:04,080 --> 00:47:06,490
to their ongoing wind problem.

426
00:47:14,256 --> 00:47:17,680
Instead of sitting around feeling bloated
after a bellyfull of leaves,

427
00:47:17,856 --> 00:47:20,506
these monkeys are on a mission.

428
00:47:26,928 --> 00:47:29,242
They single out their target...

429
00:47:35,376 --> 00:47:37,930
And wait for the right moment to strike.

430
00:47:46,080 --> 00:47:49,392
Without warning, they launch their attack.

431
00:48:01,584 --> 00:48:04,840
It's a constant battle
for the island's charcoal sellers.

432
00:48:08,784 --> 00:48:11,744
Here in Jozani,
red colobus have long worked out

433
00:48:11,904 --> 00:48:15,514
that eating charcoal
aids the digestion of exotic leaves.

434
00:48:19,872 --> 00:48:23,779
This learned behavior
passed down from mother to young

435
00:48:23,952 --> 00:48:26,158
is unique to Unguji's troops.

436
00:48:32,148 --> 00:48:33,860
As night draws in,

437
00:48:34,020 --> 00:48:37,822
another of Zanzibar's giants
emerges from the shadows.

438
00:48:42,804 --> 00:48:45,668
This is no ordinary rat.

439
00:48:45,828 --> 00:48:47,540
At over a meter in length,

440
00:48:47,700 --> 00:48:50,158
it's one of the largest in the world.

441
00:48:54,036 --> 00:48:56,372
Known as a giant pouched rat,

442
00:48:56,532 --> 00:48:58,724
it's able to store vast amounts of food

443
00:48:58,884 --> 00:49:01,246
in its expandable cheeks.

444
00:49:03,396 --> 00:49:05,588
Its eyesight is very poor,

445
00:49:05,748 --> 00:49:09,616
but is compensated for
by an excellent sense of smell and hearing.

446
00:49:12,996 --> 00:49:15,668
Its giant nose is so sensitive,

447
00:49:15,828 --> 00:49:17,924
scientists have begun using this species

448
00:49:18,084 --> 00:49:19,892
to sniff out land mines

449
00:49:20,052 --> 00:49:23,662
and detect human diseases,
such as tubercolosis.

450
00:49:31,236 --> 00:49:36,435
To avoid predators, the rat changes
its burrow site every two weeks.

451
00:49:36,612 --> 00:49:39,166
And this may not be a bad thing.

452
00:49:42,564 --> 00:49:46,612
A unique species of leopard
is still thought to roam these woods.

453
00:49:50,436 --> 00:49:53,156
Legend has it many were kept by witches

454
00:49:53,316 --> 00:49:56,446
and used to hound local villages.

455
00:50:07,188 --> 00:50:09,572
Because of this supernatural association,

456
00:50:09,732 --> 00:50:13,639
the island's leopard
has been hunted to the brink of extinction.

457
00:50:18,612 --> 00:50:21,044
Zanzibar's giant rat population however

458
00:50:21,204 --> 00:50:23,374
continues to flourish.

459
00:50:31,860 --> 00:50:34,318
Zanzibar is an island paradise.

460
00:50:39,156 --> 00:50:41,662
People live by the turning of the tides.

461
00:50:45,732 --> 00:50:48,164
And its isolation
has seen Zanzibar's creatures

462
00:50:48,324 --> 00:50:50,494
evolve and grow.

463
00:50:55,140 --> 00:50:57,812
Many mainland species
are forced to remain small

464
00:50:57,972 --> 00:50:59,902
to escape predators,

465
00:51:03,396 --> 00:51:06,622
but island animals have an easier life.

466
00:51:10,740 --> 00:51:13,844
Abundant food, less competition

467
00:51:14,004 --> 00:51:17,662
and fewer predators
have had a positive effect.

468
00:51:21,108 --> 00:51:23,924
They've allowed Zanzibar,
and its many islands,

469
00:51:24,084 --> 00:51:27,022
to become a wilderness of giants.