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