1
00:00:24,280 --> 00:00:27,040
It's a universal dream
to fly like a bird.


2
00:00:29,840 --> 00:00:32,560
To soar on wings into the heavens.


3
00:00:39,080 --> 00:00:42,800
But it's nothing
compared to the reality.


4
00:00:50,320 --> 00:00:53,960
Experience our planet
as never before.


5
00:00:58,920 --> 00:01:01,080
A bird's-eye view.


6
00:01:09,160 --> 00:01:12,520
This is a journey
that will embrace the world...


7
00:01:20,920 --> 00:01:23,840
..showing us astonishing
natural events...


8
00:01:30,480 --> 00:01:32,560
..extreme challenges...


9
00:01:39,320 --> 00:01:40,920
..and hard-won rewards.


10
00:01:49,320 --> 00:01:51,280
This is the world on the wing.


11
00:02:14,560 --> 00:02:18,800
It's spring in the Gulf of Mexico,
in the far south of North America.


12
00:02:20,560 --> 00:02:23,720
Families of snow geese are
soon to begin an epic journey


13
00:02:23,720 --> 00:02:25,440
across a continent.


14
00:02:26,920 --> 00:02:30,120
It's a migration made by
millions upon millions of birds.


15
00:02:36,360 --> 00:02:37,720
Before they leave,


16
00:02:37,720 --> 00:02:40,680
individual families
join thousands of other geese


17
00:02:40,680 --> 00:02:43,800
preparing for the great trek
northwards.


18
00:02:44,840 --> 00:02:49,280
They become one of a crowd made
up of hundreds of other families.


19
00:03:09,480 --> 00:03:13,920
But this spectacular gathering
doesn't go unnoticed.


20
00:03:13,920 --> 00:03:17,080
Out of the heavens
soars America's national bird -


21
00:03:17,080 --> 00:03:19,840
an aerial predator
of cunning and power.


22
00:03:22,720 --> 00:03:26,800
The parents warn their young, and
the message spreads like wildfire.


23
00:03:43,280 --> 00:03:47,680
The bald eagle flushes the birds,
checking for signs of weakness.


24
00:04:00,680 --> 00:04:02,880
The panic spreads
like a Mexican wave,


25
00:04:02,880 --> 00:04:06,160
but still, among the masses,
the families stick together.


26
00:04:20,000 --> 00:04:22,520
As more and more families
take to the air,


27
00:04:22,520 --> 00:04:26,400
they create a snowstorm of geese
that confuses the eagle.


28
00:04:37,920 --> 00:04:42,440
The massed ranks create a whiteout,
impossible to see through.


29
00:04:50,600 --> 00:04:53,240
She must look for easier options.


30
00:04:55,680 --> 00:04:58,080
Overwintering coots
are a far better bet.


31
00:05:00,920 --> 00:05:03,720
Unlike geese,
they need a long take-off.


32
00:05:16,880 --> 00:05:18,880
They are also weak fliers.


33
00:05:18,880 --> 00:05:20,560
It heads back to the water...


34
00:05:30,200 --> 00:05:33,200
and performs a disappearing act...


35
00:05:36,200 --> 00:05:38,480
..diving two metres
below the surface.


36
00:05:40,080 --> 00:05:41,680
But the game isn't up yet.


37
00:05:44,040 --> 00:05:46,720
Another coot dives,
but the water's shallow,


38
00:05:46,720 --> 00:05:50,520
and the eagle's pin-sharp vision
can see him.


39
00:06:03,080 --> 00:06:04,560
It's a fatal mistake.


40
00:06:09,360 --> 00:06:12,240
The eagle will follow
the migrating flocks,


41
00:06:12,240 --> 00:06:14,640
hoping for yet more opportunities.


42
00:06:18,400 --> 00:06:20,760
The snow geese have
a tight schedule to keep


43
00:06:20,760 --> 00:06:23,440
if they are to reach
the Arctic in time to breed.


44
00:06:23,440 --> 00:06:25,000
It's 3,000 miles away.


45
00:06:36,560 --> 00:06:40,160
They become part of a spring
migration across the continent,


46
00:06:40,160 --> 00:06:43,080
one that features
millions of other birds.


47
00:06:57,360 --> 00:07:01,720
Brown pelicans are one of
America's most charismatic birds.


48
00:07:03,480 --> 00:07:06,760
They breed in the warm waters
of Baja California,


49
00:07:06,760 --> 00:07:09,120
but travel north in search of fish.


50
00:07:17,520 --> 00:07:20,800
The brown juveniles are still
learning the ways of the ocean.


51
00:07:20,800 --> 00:07:25,480
Their more colourful elders
have many secrets to pass on.


52
00:07:28,880 --> 00:07:33,600
The youngsters must learn the habits
of every sea creature below.


53
00:07:42,200 --> 00:07:46,280
He soon discovers that some
can guide him to a meal.


54
00:07:58,640 --> 00:08:01,440
Humpback whales
are the easiest to spot -


55
00:08:01,440 --> 00:08:05,960
they have travelled over 2,500 miles
from the Arctic to breed here.


56
00:08:08,040 --> 00:08:13,920
The males announce their arrival by
slapping their five-metre long fins.


57
00:08:26,400 --> 00:08:30,560
But this "breaching"
is a more spectacular way
of gaining attention.


58
00:08:40,280 --> 00:08:43,400
35 tons of blubber
make quite a splash!


59
00:08:50,760 --> 00:08:55,480
The pelican soon discovers
that these show-offs have nothing
to divulge at this time of year.


60
00:08:55,480 --> 00:08:58,320
They are too preoccupied
with each other.


61
00:09:09,080 --> 00:09:12,800
Dolphins, on the other hand,
are a different proposition.


62
00:09:15,480 --> 00:09:19,440
The youngsters learn that dolphins
follow schools of anchovies.


63
00:09:28,800 --> 00:09:32,680
Huge pods form around
the biggest shoals.


64
00:09:37,560 --> 00:09:41,040
The pelicans take their cue
to dive from the dolphins.


65
00:09:50,000 --> 00:09:53,280
The deeper the fish,
the higher the birds dive.


66
00:10:00,680 --> 00:10:04,880
The young pelican is perfectly
adapted for plunge attacks.


67
00:10:06,400 --> 00:10:07,840
As he hits the surface,


68
00:10:07,840 --> 00:10:12,320
his legs and wings thrust backwards,
forcing his bill around his prey.


69
00:10:24,800 --> 00:10:28,480
His pouch gapes,
sucking in ten litres of water


70
00:10:28,480 --> 00:10:31,000
as his upper bill closes the trap.


71
00:11:02,200 --> 00:11:08,360
Brown pelicans leave these
pleasant, balmy seas when fishing
opportunities arise further north.


72
00:11:12,200 --> 00:11:17,520
Birds of prey arriving from
South America have their own
appointments to keep.


73
00:11:21,880 --> 00:11:24,480
Many red-tail hawks stop
for a bite to eat


74
00:11:24,480 --> 00:11:27,040
at Bracken Cave in southern Texas.


75
00:11:31,120 --> 00:11:33,800
High on the menu are
20 million free-tailed bats


76
00:11:33,800 --> 00:11:37,000
that have just arrived
from Mexico to breed.


77
00:11:39,440 --> 00:11:43,000
It's the largest gathering
of mammals on the planet.


78
00:11:49,040 --> 00:11:51,760
As the bats leave
to feed each evening,


79
00:11:51,760 --> 00:11:54,640
they run the gauntlet
of the waiting hunters.


80
00:11:56,800 --> 00:12:00,640
For a rookie hawk that's just
arrived, they're quite a challenge.


81
00:12:09,840 --> 00:12:12,000
She has to learn how to catch them.


82
00:12:26,840 --> 00:12:31,680
But she's pitched against
the fastest and most agile bats
in the world.


83
00:12:36,800 --> 00:12:38,640
They run rings round her.


84
00:12:44,760 --> 00:12:49,120
The sheer numbers are overwhelming,
especially for a beginner.


85
00:13:11,480 --> 00:13:13,560
She tries again.


86
00:13:23,840 --> 00:13:25,280
Then again.


87
00:13:27,760 --> 00:13:31,680
Finally, she spots a bat
that's strayed from the mass,


88
00:13:31,680 --> 00:13:34,440
and flicks her back claw
to hook it.


89
00:13:37,520 --> 00:13:41,920
Impressive stuff, but nothing
compared to the real top guns.


90
00:14:11,760 --> 00:14:16,960
These experienced hunters
have learnt the best technique,


91
00:14:16,960 --> 00:14:20,120
dive-bombing
the bats at over 100 mph.


92
00:14:53,000 --> 00:14:57,520
The best can catch a bat with one
talon while still holding another.


93
00:15:03,880 --> 00:15:07,600
The "best of the best"
stay for the entire summer,


94
00:15:07,600 --> 00:15:12,880
but most migrating hawks simply
use the cave as a drive-through
restaurant.


95
00:15:20,600 --> 00:15:24,640
Like hawks, snow geese
travel along well-defined routes,


96
00:15:24,640 --> 00:15:27,120
known as flyways.


97
00:15:27,120 --> 00:15:29,600
The Mississippi flyway
is the most popular,


98
00:15:29,600 --> 00:15:32,920
as families can drop down
any time to rest or feed.


99
00:15:32,920 --> 00:15:34,680
BOAT HORN BLOWS


100
00:15:39,280 --> 00:15:42,320
Youngsters stick close
to their parents -


101
00:15:42,320 --> 00:15:46,720
those that are making
their first migration
will still be learning the way.


102
00:15:56,280 --> 00:15:58,880
The young will only need
to make the journey once


103
00:15:58,880 --> 00:16:01,280
to remember it for a lifetime.


104
00:16:02,480 --> 00:16:05,360
But not all routes
are quite so easy.


105
00:16:14,840 --> 00:16:18,320
Birds taking the western route
have to cross hazardous deserts,


106
00:16:18,320 --> 00:16:20,040
such as the Grand Canyon.


107
00:16:26,720 --> 00:16:31,120
Hawks can use the updraughts
rising from the canyon walls


108
00:16:31,120 --> 00:16:34,760
to glide onwards and upwards
to more forgiving lands.


109
00:16:39,120 --> 00:16:41,960
The master of these travellers
is the bald eagle.


110
00:16:43,080 --> 00:16:47,120
She, too, is exquisitely sensitive
to rising air currents.


111
00:16:56,760 --> 00:16:58,480
She is a slope-soarer,


112
00:16:58,480 --> 00:17:02,640
adapted to exploit the uplift
created by hills and cliffs.


113
00:17:05,280 --> 00:17:07,840
There is no shortage of uplift here!


114
00:17:09,720 --> 00:17:11,320
Apart from the wind,


115
00:17:11,320 --> 00:17:14,840
the canyon appears to offer little
for such a water-loving bird.


116
00:17:21,280 --> 00:17:24,400
But the gorge was
carved out by water.


117
00:17:30,040 --> 00:17:33,800
And here, the mighty
Colorado still flows.


118
00:17:41,320 --> 00:17:45,440
It has sustained life
in these deserts for
the last 17 million years.


119
00:17:45,440 --> 00:17:48,600
It still feeds the eagles
that are travelling through.


120
00:18:01,200 --> 00:18:06,240
Just 85 miles further east
lies Monument Valley.


121
00:18:06,240 --> 00:18:09,920
It has no obvious attractions
for migrating birds at all.


122
00:18:09,920 --> 00:18:13,400
Even so, many snow geese
taking the western route


123
00:18:13,400 --> 00:18:15,840
pass over it as they travel north.


124
00:18:15,840 --> 00:18:17,960
Like their Mississippi counterparts,


125
00:18:17,960 --> 00:18:21,400
the adults recognise
the landscape features,


126
00:18:21,400 --> 00:18:23,720
and guide their young through.


127
00:18:36,520 --> 00:18:40,880
But geese needing food or water
face more of a challenge out here.


128
00:18:44,320 --> 00:18:50,240
Unlike the Mississippi, the desert
offers no food or water at all.


129
00:18:55,160 --> 00:18:59,440
From the goose's perspective,
this is a hard land to cross.


130
00:19:15,680 --> 00:19:18,680
Geese must flap hard and fast
to stay aloft


131
00:19:18,680 --> 00:19:23,040
and push onwards to the fertile
lands that lie further north.


132
00:19:23,040 --> 00:19:25,720
But like the walls
of the Grand Canyon,


133
00:19:25,720 --> 00:19:29,400
the huge sandstone buttresses
deflect air upwards.


134
00:19:29,400 --> 00:19:32,440
It's just the help a family needs.


135
00:19:33,520 --> 00:19:36,400
Migrating geese
appreciate these free rides,


136
00:19:36,400 --> 00:19:39,720
using them to join
other flocks flying overhead.


137
00:19:46,200 --> 00:19:49,800
On the West Coast,
pelicans are also on the move.


138
00:19:49,800 --> 00:19:51,680
They must keep to a strict timetable


139
00:19:51,680 --> 00:19:54,760
if they are not to miss
a great feeding event.


140
00:19:57,520 --> 00:20:00,880
They say, "A wonderful bird
is the pelican,


141
00:20:00,880 --> 00:20:03,680
"his bill can hold more
than his belly can".


142
00:20:03,680 --> 00:20:08,040
While it's true he could swallow
five kilos of fish in one gulp,


143
00:20:08,040 --> 00:20:10,960
these rays are way
out of his league.


144
00:20:17,600 --> 00:20:21,400
They trawl for tiny shrimps
using their mouths as a net.


145
00:20:22,560 --> 00:20:24,800
They are also known as Devil rays,


146
00:20:24,800 --> 00:20:28,360
and at times they appear to display
supernatural powers.


147
00:20:35,240 --> 00:20:37,200
It seems they too can fly!


148
00:21:02,200 --> 00:21:07,240
Why they indulge in such weird
aerobatics is anyone's guess.


149
00:21:08,280 --> 00:21:12,040
But the pelican's aerial perspective


150
00:21:12,040 --> 00:21:16,000
reveals that the jumps happen
around the edge of the shoal.


151
00:21:16,000 --> 00:21:19,400
Perhaps they panic the shrimps
into the mouths of the other rays.


152
00:21:40,000 --> 00:21:42,360
Or maybe they're just showing off!


153
00:21:51,800 --> 00:21:55,280
But the rays' aerobatics
won't delay the pelicans.


154
00:21:55,280 --> 00:22:01,320
They are heading for one of
the most bizarre natural
spectacles in North America.


155
00:22:02,640 --> 00:22:05,200
The youngsters follow the adults
as they navigate


156
00:22:05,200 --> 00:22:08,120
to a very special beach in
the Sea of Cortez.


157
00:22:14,120 --> 00:22:16,240
They are right on time.


158
00:22:16,240 --> 00:22:19,360
The tide has reached
its highest point.


159
00:22:23,480 --> 00:22:26,320
The sea now reveals its prize.


160
00:22:33,000 --> 00:22:36,480
An entire shoreline,
carpeted in gulf grunion.


161
00:22:38,640 --> 00:22:42,640
The adult pelicans know exactly
when the grunion will arrive,


162
00:22:42,640 --> 00:22:46,000
passing on this knowledge to
the youngsters travelling with them.


163
00:22:48,080 --> 00:22:51,800
The grunion surf ashore,
and the females burrow backwards,


164
00:22:51,800 --> 00:22:54,400
laying their eggs
in the exposed sand.


165
00:22:55,520 --> 00:22:58,760
The males then coil around
to fertilise them.


166
00:23:05,440 --> 00:23:09,880
They are laying their eggs out of
the reach of aquatic predators,


167
00:23:09,880 --> 00:23:11,680
above the high tide mark.


168
00:23:13,080 --> 00:23:17,800
Their young will hatch on the next
spring tide and return to the sea.


169
00:23:19,480 --> 00:23:23,720
These fish out of water should be
a doddle for a pelican to catch.


170
00:23:23,720 --> 00:23:26,960
But they're missing
the right tools for the job.


171
00:23:34,040 --> 00:23:38,320
Their bills are too unwieldy
to scoop the grunion from the sand.


172
00:23:44,440 --> 00:23:48,040
The pelicans are relegated
to fishing in the surf zone


173
00:23:48,040 --> 00:23:50,200
as the orgy goes on behind.


174
00:23:54,400 --> 00:23:58,160
Not the easiest place to fish,
especially on a rough day.


175
00:24:22,840 --> 00:24:26,800
But as the fish make their getaway,
the pelicans seize their chance


176
00:24:26,800 --> 00:24:31,320
and go back to what they know best -


177
00:24:31,320 --> 00:24:33,440
plunge diving on to their prey.


178
00:24:50,800 --> 00:24:53,720
The marshlands of South Carolina
are the setting


179
00:24:53,720 --> 00:24:56,160
for another strange fishing story.


180
00:24:58,720 --> 00:25:02,800
One that involves
a very talented pod of dolphins.


181
00:25:10,280 --> 00:25:15,040
They are closely watched
by a flock of great egrets,


182
00:25:15,040 --> 00:25:18,560
who have become experts
on the dolphins' behaviour.


183
00:25:44,800 --> 00:25:47,880
As the dolphins manoeuvre,
the egrets shadow them,


184
00:25:47,880 --> 00:25:51,040
leap-frogging
from one spot to the next.


185
00:25:54,680 --> 00:25:58,200
Their cue is the moment
a dolphin pops to the surface,


186
00:25:58,200 --> 00:26:02,080
checking the position
of the nearest mud bank.


187
00:26:02,080 --> 00:26:06,280
The egrets are poised
and ready for action.


188
00:26:06,280 --> 00:26:07,440
Then it happens.


189
00:26:10,960 --> 00:26:13,920
The dolphins drive
the fish shoal ashore.


190
00:26:18,320 --> 00:26:21,200
As the fish flounder,
the dolphins scoop them up.


191
00:26:27,280 --> 00:26:30,400
But the egrets also pile in.


192
00:26:38,320 --> 00:26:43,800
This is the only place
in the world where dolphins
"strand feed" like this,


193
00:26:43,800 --> 00:26:46,920
and the local birds have learnt
to make the most of it.


194
00:26:59,840 --> 00:27:02,480
As the tide drops further,


195
00:27:02,480 --> 00:27:04,920
the dolphins search
for more fish shoals.


196
00:27:24,800 --> 00:27:29,960
Strangely, the dolphins always use
their right sides to push ashore.


197
00:27:34,400 --> 00:27:38,960
Their bellies flush pink
with the excitement of it all.


198
00:27:54,400 --> 00:27:57,600
The young dolphins pick up this
technique from their parents,


199
00:27:57,600 --> 00:27:59,880
as do the egrets that follow them.


200
00:28:02,720 --> 00:28:04,880
Many no longer fish for themselves,


201
00:28:04,880 --> 00:28:08,400
and totally rely upon
the dolphins' cast-offs.


202
00:28:12,360 --> 00:28:16,320
The egrets are living proof
of birds' extraordinary ability


203
00:28:16,320 --> 00:28:18,920
to adapt to the opportunities
on offer.


204
00:28:25,040 --> 00:28:29,160
Snow geese taking the Mississippi
route pass over Nebraska.


205
00:28:29,160 --> 00:28:32,520
Here, over the last 150 years,


206
00:28:32,520 --> 00:28:37,840
natural grasslands have been
transformed into America's
grain belt.


207
00:28:37,840 --> 00:28:42,920
From the goose's perspective,
the changes are a major improvement,


208
00:28:42,920 --> 00:28:46,000
and now the snow geese
population is booming.


209
00:28:48,160 --> 00:28:51,080
It is increasing
at an incredible 5% per year


210
00:28:51,080 --> 00:28:54,560
as farmers grow crops that the geese
can eat on their migration.


211
00:29:40,280 --> 00:29:42,200
Many of the birds
that touch down here


212
00:29:42,200 --> 00:29:44,920
will have been flying continuously
for three days.


213
00:29:47,000 --> 00:29:51,920
They would have travelled 800 miles,
burnt over 3,000 calories


214
00:29:51,920 --> 00:29:55,600
and lost a third of their
body weight to reach here.


215
00:29:55,600 --> 00:29:58,960
The first priority is to
top up their lost reserves.


216
00:30:03,080 --> 00:30:06,880
But even best-laid plans
are at the mercy of the weather.


217
00:30:19,240 --> 00:30:21,880
An overnight snowfall
can blanket everything.


218
00:30:32,200 --> 00:30:35,920
They have no option but to move,
even on empty stomachs.


219
00:30:39,880 --> 00:30:41,800
But flying burns calories,


220
00:30:41,800 --> 00:30:45,360
and many of the migrating geese
are pretty much running on empty.


221
00:30:59,000 --> 00:31:03,560
Any young now have to rely on their
parents' knowledge of the area -


222
00:31:03,560 --> 00:31:06,320
without food,
they simply won't make it.


223
00:31:14,720 --> 00:31:16,520
In San Francisco Bay,


224
00:31:16,520 --> 00:31:19,600
the young pelican reaches
the end of his journey.


225
00:31:20,560 --> 00:31:27,240
The Golden Gate Bridge spans waters
teeming with some of the most
diverse marine life on the planet.


226
00:31:29,360 --> 00:31:31,920
Pelicans only make short migrations,


227
00:31:31,920 --> 00:31:34,840
and for many,
it's the end of their journey.


228
00:31:42,560 --> 00:31:45,960
In fact,
the prison island of Alcatraz


229
00:31:45,960 --> 00:31:49,200
is named after the
old Spanish word for pelican.


230
00:31:54,520 --> 00:31:58,000
Throughout their travels,
pelicans have learnt to find food


231
00:31:58,000 --> 00:32:01,560
by watching other animals
or using their ingenuity.


232
00:32:02,760 --> 00:32:05,120
But here, the going is easy.


233
00:32:05,120 --> 00:32:08,320
He can either catch fish
in the bountiful waters of the bay


234
00:32:08,320 --> 00:32:11,160
or scavenge on waste discarded
by fishing boats.


235
00:32:14,800 --> 00:32:17,280
He can even partner
with Californian sea lions.


236
00:32:18,680 --> 00:32:21,960
Like dolphins, they help
find and corral the shoals.


237
00:32:23,120 --> 00:32:25,560
With plenty of food to be had,


238
00:32:25,560 --> 00:32:29,920
more than 1,000 sea lions laze
around without a care in the world.


239
00:32:41,440 --> 00:32:44,080
It's a carefree end
to the pelicans' journey,


240
00:32:44,080 --> 00:32:46,800
but it is the beginning of another.


241
00:32:49,440 --> 00:32:51,360
These are California gulls,


242
00:32:51,360 --> 00:32:55,760
a bird that lives on his wits
around the harbours of the
Californian coast.


243
00:32:57,640 --> 00:32:59,840
But despite their
love of the seaside,


244
00:32:59,840 --> 00:33:02,200
each spring they hear
the call of the wild


245
00:33:02,200 --> 00:33:06,200
and all 65,000 of them
up sticks and leave.


246
00:33:10,600 --> 00:33:16,040
They head 200 miles inland
to a barren salty lagoon
known as Mono Lake.


247
00:33:19,600 --> 00:33:24,280
Here, towers of calcium carbonate
rise from the lake surface,


248
00:33:24,280 --> 00:33:26,400
creating a surreal landscape.


249
00:33:31,000 --> 00:33:35,320
It makes a stark contrast to the
comforts of the gulls' usual home


250
00:33:35,320 --> 00:33:37,360
along the San Francisco seafront.


251
00:33:41,000 --> 00:33:42,920
Even the water is poisonous -


252
00:33:42,920 --> 00:33:46,280
a caustic chemical brew
of alkaline salts.


253
00:33:46,280 --> 00:33:51,560
Despite its lack of amenities, the
gulls flock here in their thousands.


254
00:33:53,840 --> 00:33:58,440
Each morning, they wait for an event
that happens as the day warms up.


255
00:33:59,480 --> 00:34:04,400
Suddenly, the shoreline fills
with vast clouds of brine flies,


256
00:34:04,400 --> 00:34:06,360
billions of them.


257
00:34:12,080 --> 00:34:15,600
For the gulls,
it's a feast like no other.


258
00:34:17,200 --> 00:34:21,400
As the flies gather to breed
and feed, they turn the sand black.


259
00:34:31,160 --> 00:34:34,680
His technique is anything
but sophisticated -


260
00:34:34,680 --> 00:34:36,920
he just opens his mouth and runs.


261
00:34:53,720 --> 00:34:56,160
It may look inefficient,


262
00:34:56,160 --> 00:34:59,000
but each fly
contains seven calories.


263
00:34:59,000 --> 00:35:00,800
He just has to catch 60 a day.


264
00:35:41,880 --> 00:35:44,160
Here, the living is easy


265
00:35:44,160 --> 00:35:48,120
so the gulls come here each summer
to raise their families.


266
00:35:56,800 --> 00:36:00,120
Food is also top priority
for snow goose families.


267
00:36:02,280 --> 00:36:05,360
When snow covers everything,
there is none to be found.


268
00:36:15,680 --> 00:36:17,320
YOUNG GEESE SQUAWK


269
00:36:17,320 --> 00:36:20,320
But mother geese
know exactly where to go.


270
00:36:23,520 --> 00:36:27,680
In fact, thousands of snow goose
families have exactly the same idea.


271
00:36:32,240 --> 00:36:35,320
The marshes of
the Platte River Basin


272
00:36:35,320 --> 00:36:37,320
offer plenty of natural food,


273
00:36:37,320 --> 00:36:38,720
even in bad weather.


274
00:36:41,080 --> 00:36:44,080
Two million geese take refuge here


275
00:36:44,080 --> 00:36:47,640
as they wait for the weather
to change for the better.


276
00:37:04,520 --> 00:37:05,920
But where geese gather,


277
00:37:05,920 --> 00:37:07,280
so do the eagles.


278
00:37:18,280 --> 00:37:21,320
The youngsters keep close
to their parents,


279
00:37:21,320 --> 00:37:22,960
hiding among the masses.


280
00:37:24,600 --> 00:37:27,760
As before, the eagle's tactic
is to divide and conquer,


281
00:37:27,760 --> 00:37:31,680
harassing and fragmenting the flocks
to single out the weaklings.


282
00:37:32,720 --> 00:37:35,840
But healthy snow geese
are ambitious targets


283
00:37:35,840 --> 00:37:38,760
and there are thousands
of other waterfowl on offer.


284
00:37:46,440 --> 00:37:50,400
Mallards are certainly worth a try.


285
00:37:50,400 --> 00:37:53,680
The eagle encourages others
to join the hunt.


286
00:37:53,680 --> 00:37:55,680
EAGLE CRIES


287
00:38:01,640 --> 00:38:05,640
They pick out any weakened
by the ordeals of the journey.


288
00:38:10,800 --> 00:38:12,840
MALLARD QUACKS


289
00:38:35,280 --> 00:38:39,400
With so much prey around,
the eagles can relax and socialise.


290
00:38:39,400 --> 00:38:42,160
They even start to play
with their food.


291
00:38:44,840 --> 00:38:45,960
Missed!


292
00:38:53,480 --> 00:38:55,680
The youngster sees
if he can do better.


293
00:39:03,720 --> 00:39:05,040
Anyone can have a go.


294
00:39:11,760 --> 00:39:14,200
Locking talons is a popular tactic.


295
00:39:20,000 --> 00:39:21,400
Tackling is allowed


296
00:39:21,400 --> 00:39:23,360
and soon everyone piles in.


297
00:39:32,960 --> 00:39:35,880
Even scraps are used
for passing practice.


298
00:39:40,240 --> 00:39:43,320
These games are all about
establishing relationships


299
00:39:43,320 --> 00:39:45,520
and perfecting combat skills.


300
00:39:58,800 --> 00:40:01,640
Bald eagles are
the most social of all eagles.


301
00:40:01,640 --> 00:40:02,800
By playing games,


302
00:40:02,800 --> 00:40:06,160
the young birds learn
survival skills from the adults.


303
00:40:15,600 --> 00:40:17,280
The sport passes the time


304
00:40:17,280 --> 00:40:20,440
as all the birds wait
for the weather to change.


305
00:40:24,800 --> 00:40:26,160
As the days go by,


306
00:40:26,160 --> 00:40:28,880
all along Nebraska's Platte River,


307
00:40:28,880 --> 00:40:30,760
there is an air of excitement.


308
00:40:30,760 --> 00:40:34,000
The weather has changed
in their favour.


309
00:40:34,000 --> 00:40:35,560
It's time to check out.


310
00:40:44,160 --> 00:40:48,160
100,000 snow geese
launch themselves into the air.


311
00:40:53,840 --> 00:40:55,800
And that's just a start.


312
00:40:55,800 --> 00:40:58,800
Two million birds
are soon on the move again.


313
00:41:11,800 --> 00:41:15,600
Many families head on north
over the Badlands of Dakota.


314
00:41:26,760 --> 00:41:30,720
The barren landscape
soon gives way to natural grassland.


315
00:41:34,480 --> 00:41:37,160
The prairies stretch
for hundreds of miles


316
00:41:37,160 --> 00:41:40,920
and provide grazing for
the largest land mammal in America.


317
00:41:47,400 --> 00:41:51,320
The bison attract
a very different flying traveller,


318
00:41:51,320 --> 00:41:52,880
cowbirds.


319
00:42:02,520 --> 00:42:04,320
As the bison migrate,


320
00:42:04,320 --> 00:42:06,560
the cowbirds travel with them.


321
00:42:06,560 --> 00:42:11,240
Like cuckoos, they even lay
their eggs in other birds' nests,


322
00:42:11,240 --> 00:42:13,520
so they never have to stop moving.


323
00:42:18,760 --> 00:42:21,160
They rely on the bison
to stir up insects.


324
00:42:21,160 --> 00:42:24,120
They know their every move...


325
00:42:26,680 --> 00:42:29,000
..and when it's wisest
to keep out of the way.


326
00:42:32,640 --> 00:42:35,280
A dust-bathing bison
is a force to be reckoned with


327
00:42:35,280 --> 00:42:39,240
but the cowbirds risk their lives
to grab fleeing insects.


328
00:42:52,800 --> 00:42:53,880
BISON SNORTS


329
00:42:58,480 --> 00:43:02,680
Males fighting over females
are a frequent occupational hazard.


330
00:43:02,680 --> 00:43:05,800
But the birds are experts
on bison behaviour


331
00:43:05,800 --> 00:43:09,240
and know just how to dodge
the battling beasts.


332
00:43:12,400 --> 00:43:16,520
The bisons' collisions
are like a car crashing at 30 mph.


333
00:43:21,320 --> 00:43:25,800
Wisely, the birds
stay out of the impact zone.


334
00:44:15,200 --> 00:44:18,160
These one-ton beasts
and their feathered friends


335
00:44:18,160 --> 00:44:19,880
once numbered millions.


336
00:44:24,840 --> 00:44:28,680
But the same landscape changes that
have helped the snow geese prosper


337
00:44:28,680 --> 00:44:32,440
have given the bison and cowbirds
little space to roam.


338
00:44:39,680 --> 00:44:41,880
On the East Coast, in Delaware Bay,


339
00:44:41,880 --> 00:44:44,640
another animal migration takes place


340
00:44:44,640 --> 00:44:46,640
just as it has done
for aeons of time.


341
00:44:50,040 --> 00:44:53,240
Over one million shore birds
arrive from South America


342
00:44:53,240 --> 00:44:56,040
to take part
in this extraordinary event.


343
00:45:00,640 --> 00:45:04,160
They time their visit
to the highest spring tides.


344
00:45:05,920 --> 00:45:09,600
It's now that thousands
of bizarre, prehistoric creatures


345
00:45:09,600 --> 00:45:11,160
emerge from the ocean.


346
00:45:14,680 --> 00:45:16,960
Horseshoe crabs.


347
00:45:29,800 --> 00:45:31,640
Like the grunion in Mexico,


348
00:45:31,640 --> 00:45:37,200
they too aim to lay their eggs
out of the reach of predatory fish.


349
00:45:37,200 --> 00:45:41,000
It's a plan that worked millions
of years ago, before birds evolved


350
00:45:41,000 --> 00:45:43,640
but now the secret's out


351
00:45:43,640 --> 00:45:45,680
and the crabs
suffer the consequences.


352
00:45:48,320 --> 00:45:52,480
Sanderlings and sandpipers are
first to gather on the strand line.


353
00:45:59,280 --> 00:46:02,840
They are like kids
playing dare with the waves


354
00:46:02,840 --> 00:46:06,560
as they pluck the freshly-laid eggs
from the sand.


355
00:46:21,640 --> 00:46:23,720
They gorge themselves silly.


356
00:46:23,720 --> 00:46:27,560
They have a journey of 2,000 miles
ahead of them.


357
00:46:42,040 --> 00:46:45,720
If the sanderlings' onslaught
wasn't bad enough for the crabs,


358
00:46:45,720 --> 00:46:48,080
then the ruddy turnstones arrive!


359
00:46:49,600 --> 00:46:51,640
Their rather unfortunate name


360
00:46:51,640 --> 00:46:54,560
actually refers
to their reddish plumage.


361
00:47:02,120 --> 00:47:04,360
But turnstone is a good
description.


362
00:47:04,360 --> 00:47:07,240
They really do
leave no stone unturned


363
00:47:07,240 --> 00:47:10,680
as they search for eggs
missed by the manic sanderlings.


364
00:47:15,760 --> 00:47:17,400
Dunlin have longer bills


365
00:47:17,400 --> 00:47:19,640
and can afford to take their time.


366
00:47:19,640 --> 00:47:23,160
They probe for eggs that were
successfully buried by the crabs.


367
00:47:38,640 --> 00:47:40,280
In this battle for the beaches


368
00:47:40,280 --> 00:47:42,800
the crabs suffer huge losses.


369
00:47:42,800 --> 00:47:46,880
Hundreds upturned by the waves find
it impossible to right themselves.


370
00:47:55,400 --> 00:47:57,120
But for all this carnage,


371
00:47:57,120 --> 00:47:59,960
the horseshoe crabs
are great survivors.


372
00:48:02,360 --> 00:48:04,560
Only a few eggs need to escape


373
00:48:04,560 --> 00:48:08,600
to allow enough young to return
to the beach in future years.


374
00:48:10,200 --> 00:48:12,320
The birds now head northwards,


375
00:48:12,320 --> 00:48:15,760
satisfied by an egg breakfast
that will last them the journey.


376
00:48:19,400 --> 00:48:22,280
Snow geese travelling up
the East Coast of America


377
00:48:22,280 --> 00:48:24,840
pass one of the greatest cities
in the world.


378
00:48:34,640 --> 00:48:37,360
They've covered two-thirds
of their journey


379
00:48:37,360 --> 00:48:39,240
in a little more than two weeks.


380
00:48:50,160 --> 00:48:53,640
New York is a busy crossroads
for travelling birds.


381
00:49:03,360 --> 00:49:07,960
Over 250 migrating species
still pass through each year


382
00:49:07,960 --> 00:49:11,680
even though their marshlands
have been replaced by real estate.


383
00:49:13,800 --> 00:49:16,480
Although things ain't
what they used to be,


384
00:49:16,480 --> 00:49:20,600
the Big Apple does give some help
to the exhausted snow geese.


385
00:49:22,920 --> 00:49:26,120
The buildings act like
the buttresses of Monument Valley,


386
00:49:26,120 --> 00:49:27,600
channelling wind upwards


387
00:49:27,600 --> 00:49:31,480
and giving geese a much-needed boost
as they move inland.


388
00:49:33,080 --> 00:49:35,760
CAR HORNS, SIRENS


389
00:49:35,760 --> 00:49:38,080
Now they will continue into Canada


390
00:49:38,080 --> 00:49:41,080
and onwards
to their breeding grounds.


391
00:49:42,800 --> 00:49:44,880
EAGLE CRIES


392
00:49:46,520 --> 00:49:48,680
Bald eagles, also heading north,


393
00:49:48,680 --> 00:49:51,200
spread out across the vast forests,


394
00:49:51,200 --> 00:49:53,320
never straying far from water.


395
00:50:07,840 --> 00:50:10,720
EAGLE CRIES


396
00:50:13,720 --> 00:50:17,160
They head for melt-water streams
and estuaries,


397
00:50:17,160 --> 00:50:19,760
as this is their best chance
for a meal.


398
00:50:29,160 --> 00:50:32,280
One particular event
draws eagles like no other.


399
00:50:34,320 --> 00:50:36,880
It also attracts grizzly bears.


400
00:50:42,160 --> 00:50:44,240
BEARS GRUNT


401
00:50:46,040 --> 00:50:49,720
The soaring eagle gets
the first sight of what's to come -


402
00:50:49,720 --> 00:50:51,360
thousands of sockeye salmon


403
00:50:51,360 --> 00:50:54,280
on the starting blocks
for a race up the river to breed.


404
00:51:08,240 --> 00:51:10,280
The eagle bides his time


405
00:51:10,280 --> 00:51:13,520
as the bears lay claim
to the best fishing spots.


406
00:51:19,960 --> 00:51:24,560
Younger eagles watch from
the sidelines, anxious to learn.


407
00:51:28,720 --> 00:51:30,120
BEAR GROWLS


408
00:51:37,800 --> 00:51:41,600
Around 15,000 fish
create the critical mass


409
00:51:41,600 --> 00:51:44,680
that fires the starting pistol.


410
00:51:44,680 --> 00:51:46,760
Once one goes, they all do.


411
00:51:55,320 --> 00:51:58,200
As the river fills with salmon,
the bears go wild.


412
00:52:04,320 --> 00:52:06,600
But the eagles hold back.


413
00:52:06,600 --> 00:52:09,440
They're happy to let the bears
do all the hard work.


414
00:52:17,880 --> 00:52:22,120
The cubs are torn between stuffing
themselves or catching more.


415
00:52:40,920 --> 00:52:42,920
An eagle seizes the moment.


416
00:52:49,880 --> 00:52:51,520
But she must eat fast.


417
00:52:51,520 --> 00:52:55,240
Mother bear doesn't like others
stealing her breakfast.


418
00:53:08,360 --> 00:53:10,960
But the bears
don't just compete with eagles.


419
00:53:10,960 --> 00:53:14,640
Arguments over feeding rights
keep tempers running high.


420
00:53:22,080 --> 00:53:25,360
BEARS ROAR


421
00:53:28,040 --> 00:53:30,880
The eagle spots another opportunity.


422
00:53:34,600 --> 00:53:37,880
As she eats,
she uses her wings to hide the fish


423
00:53:37,880 --> 00:53:40,360
but she has just seconds to spare.


424
00:53:49,960 --> 00:53:51,800
BEAR CUB YOWLS


425
00:54:04,760 --> 00:54:06,640
Finally, the bears are stuffed,


426
00:54:06,640 --> 00:54:10,040
eating just the fatty skin
and leaving the rest,


427
00:54:10,040 --> 00:54:11,920
much to the birds' delight.


428
00:54:16,880 --> 00:54:19,760
And the eagle
finally gets to eat in peace.


429
00:54:28,680 --> 00:54:31,400
It's time for the eagles to move on.


430
00:54:31,400 --> 00:54:33,600
They've got
one more appointment to make.


431
00:54:37,600 --> 00:54:42,800
All the snow goose families are
nearing the end of their journeys.


432
00:54:45,880 --> 00:54:50,240
Some pass over Niagara Falls on the
border between the USA and Canada.


433
00:55:01,400 --> 00:55:03,800
Further west,
others cross the border


434
00:55:03,800 --> 00:55:06,720
and head right for
the heart of the tundra.


435
00:55:18,720 --> 00:55:21,880
As the geese catch up
with the retreating snow,


436
00:55:21,880 --> 00:55:23,520
they stop one last time.


437
00:55:26,800 --> 00:55:29,800
But hungry bald eagles
have gathered here too,


438
00:55:29,800 --> 00:55:33,480
anticipating
the snow goose's arrival.


439
00:55:33,480 --> 00:55:37,840
Maybe now, they will finally get
to feed on their favourite prey,


440
00:55:37,840 --> 00:55:42,520
especially as the exhausted geese
are at their most vulnerable.


441
00:55:44,440 --> 00:55:47,320
The young eagle buzzes the geese.


442
00:55:53,240 --> 00:55:56,000
This time he's found a sitting
duck...


443
00:55:58,600 --> 00:56:01,800
..a youngster
weakened by her long flight.


444
00:56:05,680 --> 00:56:07,280
GEESE HONK


445
00:56:21,640 --> 00:56:24,040
The snow goose fights back.


446
00:56:24,040 --> 00:56:25,840
She even grabs his tail.


447
00:56:35,120 --> 00:56:39,120
But the eagle
puts his training into practice.


448
00:56:44,440 --> 00:56:46,880
GOOSE SQUAWKS


449
00:57:12,840 --> 00:57:14,320
A remarkable escape.


450
00:57:17,240 --> 00:57:18,440
Or is it?


451
00:57:24,200 --> 00:57:28,040
The snow goose survives
against the odds.


452
00:57:28,040 --> 00:57:31,960
And the young eagle
returns to the classroom.


453
00:57:34,400 --> 00:57:37,400
Like all birds,
he will never stop learning.


454
00:57:42,880 --> 00:57:46,360
As the weather clears,
the geese make the final short hop


455
00:57:46,360 --> 00:57:49,840
onwards to their Arctic
breeding grounds.


456
00:57:49,840 --> 00:57:52,920
They have travelled 3,000 miles
to reach here.


457
00:57:54,720 --> 00:57:58,000
It's only now that
the young leave their parents


458
00:57:58,000 --> 00:57:59,960
to raise chicks of their own.


459
00:58:01,920 --> 00:58:05,680
The bond with their mother that
guided them across North America


460
00:58:05,680 --> 00:58:08,040
is now formed
with their own offspring.


461
00:58:09,560 --> 00:58:13,240
They will learn from her the
many secrets known only to birds.


462
00:58:13,240 --> 00:58:14,760
CHICKS SQUEAK


463
00:58:18,160 --> 00:58:20,680
In the next journey
across a continent,


464
00:58:20,680 --> 00:58:22,680
we will fly with vultures,


465
00:58:22,680 --> 00:58:24,640
flamingos and fish eagles


466
00:58:24,640 --> 00:58:28,800
as we experience
a bird's-eye view of Africa.


467
00:58:51,720 --> 00:58:54,520
Subtitles by Red Bee Media Ltd


468
00:58:54,520 --> 00:58:57,160
E-mail subtitling@bbc.co.uk