Original subtitles

l cannot stay away.

Coming home to Baja California for me-

-is like walking across a thousand miles of sand-

-and finding a pool of water.

lt's an oasis for my heart.

A few very special places in the world-

-are havens for life.

Resources and shelter draw living creatures from far and near.

These places are rare. We call them oases.

Of them all, this is one of the most extraordinary.

This is my home.

lt is a hot, dry peninsula, 700 miles long-

-and surrounded by ocean.

lt is called Baja California.

l'm Exequiel Ezcurra.

l work here as an ecologist.

Today, some fellow naturalists and l will take you to places we love-

-to discover the answer to a single question:

Why does this land and this sea create an oasis?

One simple answer to that question is that there's plenty to eat.

Mercedes Guerrero studies whales that are drawn here to feed.

The whales eat floating sea life called plankton.

They find it here in huge concentrations.

Dolphins too are drawn here in tens of thousands-

-to feed their high energy lives.

Dolphins trap the schools of fish near the surface.

Birds can see the commotion from miles away and join in.

Whales follow by listening for the action underwater.

l have learned to recognise these humpback whales as individuals-

-by their special markings.

We study them to see how they live and even how they die.

The sharks did not kill this humpback-

-but we don't know what did.

l am saddened by the death of this whale.

But in this circle of hunger and life-

-even the greatest lives end.

And l know that this whale's body-

-will give new life to others.

The ocean oasis is a magnet to life.

Enriqueta Velarde studies the birds-

-that return each year to Rasa lsland.

lt's amazing.

Almost all the Herman's gulls and elegant terns in the world-

-come here to Rasa to breed.

The gulls arrive first, to establish their nest sites-

-travelling from as far away as Canada.

The terns migrate from coastal Chile and Peru.

As many as half a million birds-

-pack into this tiny island at once.

lt may seem curious that the terns nest-

-in the middle of the gulls' colony. But by living among the gulls-

-the terns gain protection from predators.

The gulls tax the terns-

-by stealing some of the food they bring in from the ocean.

Just imagine-

-the birds of Rasa catch 65 tonnes of fish each day-

-one sardine at a time.

That points to one conclusion.

This ocean must be incredibly productive.

lliana Ortega works here as a naturalist.

This is my community.

Much of my work is to show people the diversity of the wildlife-

-and to explain its biology.

For instance, it's important to get to know sharks...

...like these hammerheads.

They don't threaten us, they usually eat squid.

But with grey sharks, there is tension.

They'll eat almost anything.

You know, humans are much more dangerous to sharks-

-than they are to us.

When you spend time with sharks you begin to understand them.

And learn to respect them.

But you have to command their respect too.

See? They're always testing you.

l admire sharks.

They're a vital link in the chain of life.

Like wolves, they weed out the sick and the injured-

-leaving behind only the healthiest of their prey to reproduce.

At night, the sharks' sophisticated senses of vibration-

-and electro-conductivity serve them best.

They move faster, become more excited-

-and leave, in search of prey.

l will not follow.

Throughout the night, other predators stalk the oasis.

The moray eel is almost blind-

-but it can smell like a bloodhound.

The scorpion fish is camouflaged by day-

-but not from something that can smell it.

Daylight returns.

The frog fish begins its day.

Cornet fish stir from their slumber...

...and life rises to the morning.

Some animals come to the oasis for reasons other than hunger.

They come to breed.

These elephant seals migrate here twice each year-

-from the northern pacific.

A round trip of 6000 miles each time.

The mothers transform their thick blubber into milk.

And the milk is incredibly rich.

Just imagine, the babies put on eight pounds a day!

A male as big as a truck sees a smaller trespasser.

ln this fight over the territory where the females gather...

...bulk is power.

Elephant seals may look ugly and awkward to us-

-but they are powerful predators.

Soon they will return to the sea-

-where they spend 90% of their time-

-diving to depths of up to 1500 feet.

Ospreys are usually solitary, except here.

The abundant mullet in the ocean oasis-

-attracts so many of these fish hawks that they crowd the cliffs-

-sometimes building their nests less than a hundred metres apart.

Whenever l see them using those claw like beaks so gently-

-l can't help wondering whether instinct and emotions-

-are really so different after all.

ls this what we call sibling rivalry?

The chicks are always hungry-

-so the adult osprey are always fishing.

Underwater, other life is also busy breeding.

These Creole fish are broadcast spawners.

Milt and eggs burst into the water-

-and mix right there.

Schools of mackerel dash in to feast-

-but many eggs survive.

Other fish produce fewer eggs, but tend them carefully.

A female sergeant major lays her eggs on the rocks-

-and the male spends weeks guarding his nest-

-until the eggs hatch-

-chasing off everything else that wants a snack.

Because life in the oasis is so crowded-

-the reef here reminds me of a city.

A moray can smell something tasty.

But the baby leather bass has a refuge-

-she's specially adapted to shelter among the venomous urchins.

But other fish may threaten her sanctuary.

A hogfish attacks one of the urchins.

lts neighbours mill around, waiting for scraps-

-and careless mistakes.

ln this city, you better watch out when crossing the street.

Barnacles, attached by their heads-

-comb the water with their feet.

Life climbs on life here-

-and they're eating things l can barely see.

On the rocks of the reef we're closing in on the secret-

-that makes this fragile oasis possible.

This looks like a garden but these are not plants.

They're colonies of thousands of tiny creatures-

-that build one upon another.

All reaching out into the moving water for food.

Corals, gorgonia, sponges.

They are gathering bits of the same feast.

The richness that makes these waters so nourishing for all life.

A huge abundance of plankton.

Comb jellies and jelly fish drift with the plankton soup.

They are carnivores.

This relative of the lion's mane is armed with deadly tentacles.

Yet these tiny jacks swim unharmed among them.

This colonial jellyfish is like a floating rope-

-made up of thousands of polyps strung together-

-each fishing with its own stinging tentacle.

King angel fish savour them, perhaps they like spicy food.

A larvacean spins a web of mucus to catch the tiniest plankton.

Look at this one. l call it the little sea elephant.

lt's actually a member of the snail family.

We know plankton is the foundation for all this life-

-but why is the plankton more abundant here than anywhere else?

The answer is deep on the reef in a blizzard of life.

These are mysids.

Tiny, cold water shrimp-like creatures.

Their abundance tells us that these waters are very rich in nutrients.

The mysids also tell us that these waters are unexpectedly cool.

That coldness is a vital reason why the forces of land and sea-

-combine to create the ocean oasis.

Deep inside, our planet's mantel churns with heat.

On the surface, the coolest pieces of the earth's crust-

-sink into the mantel and drag the plates behind them-

-as if they were rafts of stone.

Five million years ago these forces-

-began to pull Baja California from the side of Mexico.

Now, look at the ocean.

Winds and the earth's rotation-

-push surface water away from the land-

-and cooler, green waters rise from the depths.

The cool water, rich in nutrients-

-nourishes the plankton that forms the base of the pyramid of life-

-creating an oasis that is unique on earth.

But, that's only half the story. The other half is on land.

lt is hard to believe, but the same forces that formed the oasis-

-also cause the dryness of the desert.

Moisture here comes from evaporation off the sea-

-so even plants depend on the ocean.

But when the water is cool, not much evaporates to make rain.

So the same cold water that brings the oasis its riches-

-also robs the land of moisture.

Life on the land is driven not just by hunger but by thirst.

Bizarre-looking boojum trees and other plants and animals-

-have developed wonderful ways to use every drop of water.

ln its thick body-

-a cactus stores the last rain like a memory.

lt survives by averaging long, dry times with occasional wet ones.

A cardon lives so slowly-

-it may only reproduce itself once in 300 years.

But there are other ways of dealing with thirst.

Hummingbirds live in the fast lane-

-with turbo-charged metabolisms-

-ten thousand times faster than the cactus.

With its mobility, a hummingbird hunts pockets of moisture-

-and follows the flowers north with the seasons.

lts life is a dance with Spring.

As the desert day cools into night-

-a kangaroo rat emerges from its burrow.

The dangerous heat of the day is gone-

-but there's a different kind of enemy out tonight.

The kangaroo rat never drinks.

Neither does the rattlesnake.

The rat's metabolism manufactures water from its food.

The snake gets moisture from its prey.

The snake searches with a second pair of eyes that sense heat-

-instead of light.

Tonight, the kangaroo rat escapes.

These creatures are finely adapted to the desert-

-a desert caused by the ocean.

Cold water and dry land.

As l cross this peninsula, every mile shows me another way-

-that land and sea shape the oasis.

As we gain altitude, more moisture condenses-

-and the vegetation thickens.

There are even pine forests up here near an observatory.

Two miles high, lichens cling to granite-

-seared by icy winds and winter snows.

l love this place.

As l travel here by helicopter or "burro"-

-l often wonder, can humans live in harmony with the ocean oasis?

High in the mountains, canyons shelter native palms-

-which drink by streams and keep the pools-

-of last year's rain in the shadow.

People have been coming here for thousands of years.

With cave paintings-

-they told of their dependence on other life of the oasis.

But we have not always been respectful of that life.

For years, people came to Mexico to hunt grey whales.

They have reason to fear us.

That is why Pachico Mayoral's experience is so extraordinary.

lt was almost 30 years ago.

One day l went fishing.

Suddenly, a whale came and rested its head on the side of my boat.

l was terrified-

-but the whale wanted to make contact, like a friend.

People call the whale the devil fish-

-because it smashes whaling boats to protect its young.

l'm always amazed about how completely they changed.

Today, Pachico takes tourists into the lagoons-

-where the whales sometimes come to the boats to greet people.

The whales are giving us a great lesson.

l believe that in this world, we are all equal.

This is my feeling toward whales.

l believe they teach us what life is.

As we grow to respect the life of the ocean oasis-

-it seems to welcome us home.

Mantas eat plankton-

-but they come here for other reasons too.

They are drawn to this part of the oasis-

-because of these little angel fish that swim out to meet them.

The angel fish go right up to the manta and gently clean it-

-eating algae and parasites off its flanks.

They also pester the remora which clings to the manta-

-so they can clean the sore the suckerfish has made.

Mantas are huge, powerful animals-

-they can swim 20 miles an hour and can easily avoid us divers.

But they choose to swim with us.

Like grey whales, the mantas seem to welcome my touch.

As l watch these creatures, one depending on the other-

-l realise how everything is connected-

-and how the land and the seas of the ocean oasis-

-are linked in a web of life that binds us all.

Around these great creatures l feel l'm graced and protected.

l wish l could protect them too.

The seas and the deserts will endure without us But we cannot survive without them.

Subtitling - John Grunditz - New Media Studios -