Galapagos (2006) - S01E03 - Forces of Change
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00:00Far out in the Eastern Pacific is a scattering of islands ruled by the brutal forces of nature.
00:28A land ravaged by fire.
00:41At the mercy of an ocean that can nourish but also cripple.
00:51A world in turmoil.
00:58This is the story of how life in Galapagos is shaped by the relentless forces of change.
01:13Past, present and future.
01:27Galapagos lies 600 miles off the coast of South America, right on the equator.
01:38It's one of the most volcanically active groups of islands in the world.
01:48And on its western edge towers the most imposing, most hostile of them all.
01:57A colossus called Fernandina.
02:14In the last 200 years this volcano has erupted at least 24 times.
02:28It's caldera towers a mile above sea level.
02:32But there's one animal that has no option but to scale its summit.
02:43The land iguana.
02:48Every pregnant female needs to find a patch of volcanic ash to feed on.
02:54But suitable sites are few and far between.
02:58And the best, warmed by fumaroles, lie right on the rim of this giant.
03:10Climbing there is a punishing ordeal which can take weeks.
03:17This female has not timed her journey well.
03:26She's been struggling to get out of the volcano.
03:30But she's got a plan.
03:33She's got a plan.
03:35She's got a plan.
03:37She's got a plan.
03:39She's got a plan.
03:41She's got a plan.
03:43She's got a plan.
03:45She's timed her journey well.
04:01All the good sites have been taken.
04:04So she has no choice but to challenge those in residence.
04:16Aggressive body language can sometimes force a victory.
04:21But the rightful owner won't relinquish her ground easily.
04:25So it's all or nothing.
04:45A ruthless catfight.
05:16The pregnant female is sent packing.
05:32Evicted from the prime nesting grounds by her rival,
05:36she's left to her own devices.
05:46She is now forced to look elsewhere.
05:50But the only other suitable sites on Fernandina
05:53lie deep within this giant caldera, half a mile down.
06:07She must make a terrifying descent.
06:15She must make a terrifying descent.
06:37The smallest slip could be fatal.
06:45The smallest slip could be fatal.
06:49Countless iguanas have been buried by landslides.
07:12Countless iguanas have been buried by landslides.
07:20But this female has a lucky escape.
07:42For any animal,
07:45finding a foothold on Galapagos is tough work.
07:50This cluster of islands are the product of a volcanic hotspot
07:54where scorching rock rises from hundreds,
07:57possibly thousands of miles beneath
08:00to puncture the Earth's crust.
08:16There are six highly active volcanoes in Galapagos today.
08:20One erupts every few years,
08:23sometimes for months at a time.
08:35Volcanism is the fundamental principle of life on Galapagos.
08:41Volcanism is the fundamental force in Galapagos.
08:46It can build an island in just tens of thousands of years.
08:51And it can wipe out life in an instant.
09:04After such catastrophic events,
09:07animals and plants are forced to find new ground.
09:12The fresh sinewy lava fields seem as lifeless as Mars.
09:22But the lava cactus is a tough pioneer.
09:27It's one of the first plants to invade this baking hot terrain,
09:32storing moisture in its succulent stems.
09:37And where the lava reaches the coastline,
09:42mangroves anchor themselves to the rocks.
09:46Four species have managed to colonize the brittle shores of Galapagos,
09:51their salt-tolerant seeds brought here on the ocean currents.
09:57Settling in bays and inlets,
10:00the roots accumulate all sorts of silty debris,
10:04helping to offer life a purchase on the shoreline.
10:15Mangroves are the most abundant species on Galapagos.
10:21Mangrove forests are crucial nursery grounds for fish,
10:25fed by plankton and nutrients flowing in and out with the tides.
10:50The tangle of vegetation also provides welcome shade from the equatorial sun.
11:07But even mangroves struggle to settle
11:10on the newest and most exposed lava shorelines.
11:15There is, however, one animal that has learned how to benefit
11:20from this harsh volcanic terrain.
11:28The Galapagos fur seal.
11:33Its ancestors arrived here long ago, from the sub-Antarctic.
11:45To escape the midday heat, they've discovered cold hideouts.
12:04Lava grottoes, formed by networks of broken lava tubes.
12:09The labyrinth of caves and tunnels provide perfect shelter for fur seals,
12:14the smallest of their kind in the world.
12:17They are a third the size of their sea lion cousins,
12:21which also visit these grottoes.
12:30Fur seals have naturally thick pelts, which provide good insulation,
12:35helped by air trapped among the fur.
12:55Big, bulging eyes allow them to hunt in the dark,
12:59a strategy that avoids direct competition with sea lions.
13:06The Galapagos fur seal.
13:24Though fur seals normally caught on land,
13:27adolescents will sometimes test the water with one another beneath the waves.
13:35The Galapagos fur seal.
14:05The Galapagos fur seal.
14:35The Galapagos fur seal.
15:06Geological force in Galapagos has created a cluster of islands,
15:11of all shapes and sizes.
15:14Some are pillars of compacted ash.
15:20Others, forged from explosions of lava.
15:24More than a hundred islands, islets and rocky outcrops sprinkle the ocean.
15:37The most unusual lies in the far northwestern reaches of the archipelago.
15:43Roca Redonda.
15:49This giant slab of unscalable rock stands a thousand feet tall
15:54and is a precious outpost for nesting seabirds.
15:59Swallow-tailed gulls.
16:05The Galapagos fur seal.
16:11The Galapagos fur seal.
16:17The Galapagos fur seal.
16:21The Galapagos fur seal.
16:25Swallow-tailed gulls are among the rarest and most exquisite.
16:38They are the only nocturnal gulls in the world
16:41and they forage at night for small fish and squid in the surface waters,
16:45aided by their unusually large eyes.
16:54The Galapagos fur seal.
17:10This island teems with life.
17:16And the productive seas that envelop it hide the secret to its wealth.
17:22There's far more to Roca Redonda than meets the eye.
17:31This island is actually the tip of a giant undersea volcano,
17:36nearly two miles tall and 12 miles wide.
17:51Bathymetric studies, examining the depths of the ocean using sonar tracks,
17:57give the archipelago a whole new dimension.
18:04Galapagos is a chain of submarine volcanoes
18:08that have coalesced into a vast underwater platform.
18:14This monumental plinth drastically changes
18:17the routing of the currents that sweep its flanks.
18:20It forces the cool Cromwell current, heading in from the west,
18:24to surge up from the ocean floor.
18:35As night falls, this mineral-rich upwelling
18:39brings the supernatural to Galapagos.
18:48The most bizarre creatures rise from the abyss.
18:59A vertical migration in a three-dimensional world.
19:17Some of these ocean vagrants are floating fortresses, providing precious shelter.
19:48For others, like this mantis shrimp larva,
19:52being small and inconspicuous is key to survival.
20:06Young slipper lobsters are exquisite glass sculptures.
20:17While cone jellies are far more flamboyant,
20:21beacons of colour in a sea of darkness.
20:25Galapagos, as it's never been seen before.
20:55As day breaks, the nutrient-rich Cromwell current is bathed by the equatorial sun,
21:01triggering blooms of microscopic algae
21:05that feed an explosion of life.
21:26This vital current has helped some of the strangest Galapagos creatures,
21:31like these cold-water penguins, to live at this latitude.
21:50The Cromwell current is only one of many that feeds Galapagos.
21:55Flowing in from the south comes another cold current, the Humboldt,
22:00merging with the south equatorial current, heading west.
22:06And from Central America comes the warm Panama flow.
22:12This current is poorer in nutrient than the others,
22:15making these northern waters the least productive.
22:25Animals here need to be resourceful.
22:30Shoals of big-eye jacks gather at particular cleaning stations,
22:34attracting the attention of colourful barber fish.
22:45The barber fish like to feed on skin parasites from the jacks.
22:55It's a mutually beneficial arrangement.
23:05Despite being on the equator,
23:07Galapagos has a limited number of warm, stable pockets of water.
23:11There are just a couple of dozen species of coral.
23:17Pavona corals bear the scars of an assault, like guinea-fowl puffer fish.
23:25They pluck crunchy mouthfuls of algae.
23:44Coral erosion helps to create an important feeding ground for spotted eagle rays.
23:55They prefer corners of Galapagos where the remains of corals and shells
23:59mingle with eroded lava.
24:08They are rich in mollusks and crustaceans,
24:11which the rays root out with their powerful, crushing jaws.
24:24These aquatic prairies are also home to rather nervous local residents.
24:30They seem to find the rays particularly intimidating.
24:36Although there's no real threat.
24:42Galapagos garden eels,
24:46who intercept plankton passing by.
24:54Galapagos garden eels
25:13In the rest of Galapagos, cold and fertile waters prevail,
25:17nourishing fields of green algae,
25:20richer here than anywhere else on the equator.
25:25Yellow-tailed surgeonfish
25:29This is an important food for gangs of yellow-tailed surgeonfish.
25:47This algal farmer, a solitary damselfish,
25:51suddenly finds his harvest hijacked by marauders.
25:55Yellow-tailed surgeonfish
25:59Yellow-tailed surgeonfish
26:19These marine pastures are a choice habitat for an ancient ocean wanderer.
26:28The Pacific green turtle.
26:40It's thought the Galapagos turtles are a unique subspecies,
26:44as they're unusually dark,
26:46perhaps to help them absorb the sun's warmth
26:49and cope better in these chilly waters.
26:58Here is one of the richest concentrations of green turtles anywhere in the Pacific.
27:29Green turtles time their gathering carefully.
27:34For a few months a year, they come together to greet and mate.
27:49Even in the most challenging conditions,
27:52nothing stops this animal from gathering.
27:58Nothing stops this ambitious male from completing the task in hand.
28:11Most green turtles lay their eggs on these shores during the warmer season,
28:16when the Humboldt current slackens.
28:19Perhaps that warmth helps with incubation.
28:23But their hatchlings will emerge several months later,
28:27a time when this cold current re-establishes itself with gusto.
28:34For half the year, the Humboldt current dominates Galapagos,
28:40arriving with cool and dry southeasterly trade winds.
28:47And it brings with it the Garua season.
28:54The misty season.
28:57The dry season.
28:59The wet season.
29:23It's now, with upwelling at its strongest
29:26and most productive, that turtles, fish and seabirds can bank on a steady supply of food.
30:56Three quarters of the world's population of blue-footed boobies live in Galapagos.
31:04They react fast when conditions are favourable.
31:09Feet are handy brakes.
31:13The name booby derives from the word bobo,
31:18the Spanish for clown,
31:22perhaps because of their exaggerated footsteps.
31:43This courtship dance is a Galapagos ritual.
31:49The higher his foot lift, the better his chances.
31:58Sky pointing builds her interest.
32:13She commits, mirroring his every move.
32:36It's back to basics.
32:42It's back to basics.
32:58Boobies can switch off their breeding season at any moment if the ocean fails to deliver.
33:03In a good year, two or three eggs are laid,
33:07with both parents taking turns to shade and incubate.
33:33Nazca boobies are close relatives of blue-footed boobies,
33:37but feed much further offshore with a wider hunting range.
33:42They also have a fixed breeding cycle.
33:54But there's a twist in their tale.
33:58Nazca boobies lay two eggs,
34:00and if both successfully hatch, there's an age gap of three to seven days.
34:16The older, larger chick is quick to stamp his authority.
34:21It's a brutal, bullying business.
34:44The elder sibling pushes the other as far as he can.
34:50As far from the nest as possible.
35:01Although this happens right under the mother's beak,
35:05she does nothing to intervene.
35:08The evicted chick now faces certain death through dehydration or predation.
35:17Only one chick ever survives.
35:21No one fully understands why siblicide always occurs among Nazca boobies.
35:29Do the parents produce two eggs as an insurance policy in case one is destroyed?
35:38Or is this an evolutionary relic from the past,
35:42when this species was comfortably able to raise two chicks?
35:50Or is it too young?
36:00Whatever the case, for Nazca boobies,
36:03this system is very effective in a world where the stakes are so high.
36:21In Galapagos, the ocean is both a giver and a taker.
36:28Life has found some extraordinary ways to deal with its mood swings.
36:35But on these remote shores,
36:38life is not as easy as it seems.
36:41The ocean is a place of peace and tranquility.
36:44It's a place of peace and tranquility.
36:48But on these remote shores,
36:51it's still a hostage to the elements.
37:08Every three to ten years,
37:10conditions in Galapagos get seriously out of kilter.
37:22It's an event described by the people of Ecuador and Peru as el niño,
37:27meaning the boy child, because it often begins around Christmas.
37:32Trade winds diminish, and the cool, humbled current slackens,
37:37failing to make its impact felt in Galapagos.
37:43It is replaced by much warmer surface waters
37:47moving east across the Pacific.
38:01Tropical downfalls sweep in, bringing welcome relief to the land.
38:22Rivers are born.
38:28Plants flourish.
38:32But the impact of el niño on the ocean is catastrophic.
38:43When it last struck, most sea lion pups starved to death.
38:51Mothers were unable to produce enough milk
38:54because of extreme shortages of their main prey, sardines.
39:01In some colonies, more than half of all sea lions died.
39:08For marine iguanas, the impact of el niño can be just as dire.
39:16Warmer water wipes out green algae, their main food source.
39:32These islands depend on the ocean as a provider of life,
39:36but nothing is guaranteed.
39:46Profound geological and climatic forces
39:50constantly reshape Galapagos.
39:53Life here is resilient and adaptable to change.
39:57And with time, it can recover from natural catastrophe.
40:05Galapagos is the most pristine tropical archipelago in the world.
40:12It is home to the world's largest sea lion population.
40:16Galapagos is the most pristine tropical archipelago in the world.
40:2595% of native wildlife is still intact.
40:33Isolation has helped protect these islands.
40:46But in recent times, a new force of change has emerged.
40:52One that is rapidly gaining momentum.
41:00Ourselves.
41:03More than 100,000 visitors come to Galapagos each year.
41:16To help support this growing interest,
41:19the local population has dramatically risen in the last 50 years,
41:23from less than 2,000 to 30,000.
41:36The resources needed to sustain visitors and residents are spiralling.
41:45There's now a sort of air and sea bridge with mainland South America.
41:50With a constant stream of people and goods,
41:53Galapagos is no longer isolated.
42:09And with this flow of traffic come unwanted species
42:12that threaten the delicate status quo.
42:23Already there are more introduced plants here than native ones.
42:31Quinine trees, brought in as a medical crop,
42:35swamp natural habitat where rare birds like petrels nest.
42:43DOG BARKS
42:50Despite efforts to curb the problems, the challenges keep on growing.
43:00Of all the introduced species, goats have been the most destructive.
43:07They were brought here centuries ago by buccaneers, whalers and sealers
43:12as a reliable food supply.
43:15But they've stripped the native plants,
43:18out-competing animals like giant tortoises.
43:42Hard though it is, the only viable solution to this problem is eradication.
44:12MUSIC
44:43MUSIC
44:55Over the last two years, tens of thousands of goats have been removed
45:00from two of the largest Galapagos islands.
45:05The land now has a chance to recover.
45:12Galapagos was, for centuries, feared and reviled.
45:20But ever since Charles Darwin's visit nearly 200 years ago,
45:25we've seen these islands in a new light
45:28and it has captured the attention of the world.
45:42This archipelago is a fascinating crucible for life.
45:50It continues to evolve and surprise.
46:02So great was its impact on Darwin
46:05that he would later claim the Galapagos islands
46:08to be the origins of all his views.
46:13MUSIC
46:21Today, it is our impact on Galapagos
46:25and how we choose to manage it
46:28that will determine the island's future.
46:31If that succeeds, it can point the way for everyone.
46:39Galapagos is, after all, a microcosm of our planet.
46:45MUSIC
47:15BIRDS CHIRP
47:45WAVES CRASH
48:15MUSIC
48:45MUSIC