Galapagos_EN_short

GALÁ PAGOS
Islands of Fire
THE ARCHIPELAGO‘S SCIENCE
AND NATURAL HISTORY
SWISS ASSOCIATION OF FRIENDS
OF THE GALÁ PAGOS ISLANDS
i

Islands of Fire
SWISS ASSOCIATION
OF FRIENDS OF THE
GALÁ PAGOS ISLANDS
This travel guide was produced by
the Swiss Association of Friends of
the Galápagos Islands, a non-profit
organization that supports projects
for the preservation of Galápagos
(www.galapagos-ch.org). The profits
from sales of this book will help
conservation and research projects
throughout the Galápagos Islands.
ii

Islands of Fire
Islands of Fire
BARREN YET DIVERSE
on Page 1
Colonisation
LUCK AND EXCEPTIONAL ABILITIES
on Page 13
Evolution
A LITTLE WORLD WITHIN ITSELF
on Page 35
Fearless?
TAME YET STRESSED
on Page 57
Test Tube Islands
A SCIENTIST‘S PARADISE
on Page 71
Conservation
STUDY AND PROTECT
on Page 95
Species Guide
IDENTIFYING THE LOCALS
on Page 113
iii

Darwin
Islands of Fire
Wolf
Pinta
Marchena
Ecuador Volcano
Wolf Volcano
Santiago
Darwin Volcano
Daphne Major
Fernandina
Alcedo Volcano
Rábida
Santa Cruz
Baltra
Isabela
Cerro Azul Volcano
Pinzón
Sierra Negra Volcano
Santo Tomás
Puerto Villamil
Bellavista
Puerto Ayora
Santa Fé
N
iv
Human settlement
100 km
Puerto Velasco Ibarra
Floreana
Champion
Gardner-por-
Floreana

Panama
Pacific Ocean
Colombia
Ecuador
Peru
Genovesa
Seymour Norte
San Cristóbal
Puerto Baquerizo
Moreno
El Progreso
Española
Gardner-por-Española

GALÁPAGOS
The Archipelago's Science
and Natural History
Swiss Association of
Friends of the Galápagos Islands
Lukas Keller, Ph.D.
Marianne Haffner, Ph.D.
Paquita Hoeck, Ph.D.
Ursina Koller, M.Sc.
Hendrik Hoeck, Ph.D.
Zurich, Switzerland
2018

SWISS ASSOCIATION OF
FRIENDS OF THE GALÁPAGOS ISLANDS
Zurich
Copyright 2018
Lukas Keller, Marianne Haffner, Paquita Hoeck,
Ursina Koller, Hendrik Hoeck
English Translation: Lilian Dutoit, Anna-Sophie Wendel,
Yves-Manuel Méan, Sabine Sonderegger, Aline Jenni,
Anja Rosebrock, Mitchell Bornstein
Layout and Design: Brian Maiorano
ISBN 978-3-9525238-3-4
All rights reserved. No part of this publication may be reproduced
or transmitted in any form without the prior written permission of
the Swiss Association of Friends of the Galápagos Islands.
Printed in Austria: DGS GmbH, A-1220 Vienna

Dedicated to those, past and present,
who have helped conserve these islands
for the generations to come.

Islands of Fire
BARREN YET DIVERSE
on Page 1
Colonisation
LUCK AND EXCEPTIONAL
ABILITIES
on Page 13
Evolution
A LITTLE WORLD
WITHIN ITSELF
on Page 35
Fearless?
TAME YET STRESSED
on Page 57

Test Tube Islands
A SCIENTIST‘S PARADISE
on Page 71
Conservation
STUDY AND PROTECT
on Page 95
Species Guide
IDENTIFYING THE LOCALS
on Page 113
Appendix
BIBLIOGRAPHY
ILLUSTRATION CREDITS
ACKNOWLEDGEMENTS
INDEX
ABOUT THE AUTHORS
on Page 142
on Page 144
on Page 146
on Page 146
on Page 153

xii

Preface
The Galápagos Islands evoke fantasies of paradise and are a dream destination
of many a traveller. The islands’ unique and bizarre creatures such
as marine iguanas, flightless cormorants, giant tortoises, or finches with
bills of all shapes and sizes have made the archipelago world-famous.
Charles Darwin was fascinated with the forms of life he explored there
during his visit in 1835. These observations would later contribute substantially
to the development of his theory of evolution. To this day, these
unique islands are considered a natural laboratory to study the processes
of evolution and are a dream research site for most biologists.
But the islands have witnessed many changes since Darwin’s visit.
Whereas a few decades ago it was mainly naturalists who visited and very
few people actually lived on the islands, tourism and the resident human
population have grown exponentially since the 1990s. The native animals
and plants have struggled with the negative effects of introduced species
and other anthropogenic changes to the formerly isolated ecosystem.
Thanks to elaborate conservation measures some of the negative effects
have been mitigated, but many challenges remain if we are to preserve this
fascinating ecosystem.
While there is no such thing as a zero-impact trip to the Galápagos,
every individual travelling there can contribute to the preservation of this
fantastic site: follow the National Park guidelines, choose your form of
travel wisely, inform yourself about the islands' uniqueness, and support
conservation and education projects that benefit the islands. With joint
efforts and a global recognition of the area's importance, the wonderful
Galápagos creatures may be enjoyed by many future generations.
About this book
Written by scientists with long-standing professional and personal connections
to Galápagos, this book provides a comprehensive overview of
the natural history and ecology of the Galápagos Islands. We investigate
the peculiar evolution that happened on these islands and how scientific
activities shape our understanding of this place and also help us preserve
it.
Using examples of specific species, this book showcases key evolutionary
processes and encourages the reader to think about ecological or behavioural
contexts when observing animals or plants in Galápagos. The
book uses abundant photographs and illustrations to give the reader a
visual tour through the different topics. It also contains a wildlife guide
showing some of the animal and plant species that the visitor is most likely
to encounter.
This book is a complement to the site-specific information that visitors
on a guided tour will receive from their National Parks guide. It also
makes for either a great pre-trip read, or an entire virtual tour for the
armchair traveller.
xiii

Islands of Fire
xiv

Islands of Fire
BARREN YET DIVERSE
Islands of Fire
V
olcanic eruptions created the Galápagos Islands, and these eruptions
continue to shape the islands even today. Only a relatively short time
ago, new habitats for plants and animals emerged—in complete isolation—in
the middle of the ocean. The islands are located at the equator
in the tropics, but the climate is subject to significant seasonal variations,
because warm and cold ocean currents meet here and interact with each
other. Above all, the region is extremely arid. That's why plants adapted to
dry climates predominate. However, the higher an island, the greater the
variety of plant communities.
1

Islands of Fire
Volcanic Islands
The Galápagos Archipelago is completely isolated in the middle of the
Pacific Ocean, about 960 km off the west coast of South America. It
consists of 19 main islands (larger than 1 sq. km) and many smaller islands,
as well as numerous islets and rocks. They are spread over more
than 120,000 sq. km of ocean and consist of a total land surface of about
8,000 sq. km.
The Galápagos Islands are of volcanic origin. On Isabela and Fernandina,
some volcanoes are still active. The westernmost island, Fernandina, is
the centre of volcanic activity. Below it, a magma chamber of molten rock
is located deep down in the earth’s interior. This hotspot is the origin of
the Galápagos Islands.
Young islands in motion
The Galápagos Islands are located on the Nazca Plate, which moves towards
South America at a rate of about 6 cm per year. While the islands
move, the hotspot—the origin of the volcanic islands—stays in the same
place.
The islands are between 35,000 and 4 million years old. It is during this
period that most evolution occurred and new species developed.
There are also sunken islands up to 2,500 m below sea level that are
probably about 5 to 14 million years old. There is evidence suggesting that
some of today’s species have ancestors that go back more than 3 to 4 million
years. Therefore, the most likely scenario is that evolution already
occurred on these islands while they were still above sea level.
Evolution of an Island Chain
Nazca
Plate
Hot magma presses
into the fissures
of the Nazca
Plate and creates
chambers close to
the surface.
2
The heat of the
magma melts the
earth’s surface
crust, causing a
volcanic eruption on
the ocean floor.
With every eruption, new layers of lava
increase the size of the volcano until it breaks
the ocean surface to form a new island.

Islands of Fire
The crust and the upper part of the earth's mantle (lithosphere) consist of plates: seven
major plates and many small ones, which are more or less mobile. The largest plates carry
continents such as South America, Africa or Eurasia. Smaller plates can carry islands, such
as the Galápagos Islands on the Nazca Plate.
The temperatures below the plates are so high that they partially melt the rock. This
subter ranean molten mass is called magma. As soon as it is expelled to the surface of the
earth, it is called lava.
Nazca
Plate
HS
HS
The Nazca Plate
moves above the
fixed hotspot
(HS), the magma
chamber.
On its journey atop the
Nazca Plate, the volcano
gradually loses its connection
to the magma
chamber and becomes
extinct.
The magma chamber
creates a new volcano.
The old island is eroded
mainly by wind and
weather, causing it to
decrease in size until
it disappears from the
ocean surface.
3

Islands of Fire
Ages of Islands and Years of Volcanic Eruptions
Formed
< 0.5 million
years ago
approx.
1150
2018
2015
1813
1993
1928
1991
Formed 1–2.5
million years ago
1906
Santiago
formed
> 2.5 million
years ago
hotspot with magma chamber
active volcano (last eruption)
sunken islands
movement of Nazca plate
Isabela
2018
2008
Santa
Cruz
San Cristóbal
Floreana
Española
N
The Nazca Plate moves southeast over the hotspot, the origin of the volcanic islands. The oldest
islands with the lowest elevations can be found in the southeastern part of the archipelago,
whereas the youngest islands with the largest volcanoes are located in the northwest. On the islands
of Isabela and Fernandina, there are still some active volcanoes. The last volcanic eruptions
took place in 2008 (Cerro Azul Volcano on Isabela), 2009 (on Fernandina), 2015 (Wolf Volcano on
Isabela), and 2018 (Sierra Negra Volcano on Isabela and La Cumbre Volcano on Fernandina).
4

Islands of Fire
In 1968, the crater floor of La Cumbre Volcano on the island of Fernandina sank by 350 m. In
1988, a lake started to form in the northern part of the crater. (dotted line: level of the crater floor
before 1968)
“... as far as the eye could reach we saw nothing but rough fields of lava, that seemed to
have hardened while the force of the wind had been rippling its liquid surface [...] About
half way down the steep south east side of the Island, a volcano burns day and night;
and near the beach a crater was pouring forth streams of lava, which on reaching the sea
caused it to bubble in an extraordinary manner.“ This is how Captain Lord George Anson
Byron described a volcanic eruption in 1825 as he lay at anchor off Fernandina during his
long journey to the Sandwich Islands (Hawaiian Islands).
5

Islands of Fire
Climate
Atypical: tropical islands with a dry climate
The dry climate on the Galápagos Islands is very atypical of the tropics.
Equally atypical is the pronounced seasonability, with a warm season between
January and May with frequent, heavy rains; and a very dry season
between June and December with only little precipitation in the island
lowlands. This anomaly can be explained by the ocean currents that meet
and interact here in the Pacific Ocean. Two currents carry cold water: the
Peru Current (Humboldt Current) from the Antarctic and the Equatorial
Undercurrent (Cromwell Current) from the deep sea. Together they are
responsible for the cool, dry season. The Panama Current brings warm
tropical water from Central America and affects the warm season. The
little precipitation that does occur during the dry season is a light drizzle
called garúa, which often stops around noon.
North Equatorial Countercurrent
Panama
Current
Equatorial
Undercurrent
South Equatorial Current
Ecuador
Humboldt Current
Peru Cu rent
“El Niño”: both a blessing and a curse
At irregular intervals about every 3 to 6 years, significant changes in ocean
current conditions lead to a much warmer and rainier season called “El
Niño”. The name is Spanish for the Infant Jesus, and is used because the
phenomenon is strongest at Christmas time. El Niño is both a blessing and
a curse: in the interior of the island, it leads to times of plenty, but it has
severe consequences for the sea and the coastal areas. Sea birds suffer
from lack of food (fish) and the high surf may flood their breeding sites as
well as the nesting grounds of sea turtles and marine iguanas. In 1982 and
1983, the water temperature became so warm that it caused the death of
most of the green algae on which marine iguanas mainly feed. As a result,
the populations of this species declined dramatically.
There are also cold and dry seasons, which are called “La Niña”.
6

Islands of Fire
The difference between a wet (El Niño) and dry year on Daphne Major.
Greater plant diversity on high islands
Most of the islands are not high and have a very dry climate. Only plants
that are highly adapted to drought can be found on such islands. However,
on high islands, there are up to five different zones, each with unique
plant communities that differ in the amount of water they need.
In higher zones, more rain falls, supporting plants that need more
moisture. The reason for the higher rainfall is that the air is cooler, causing
the moisture in the clouds to condense and fall as rain. However, on
very high islands another dry zone exists above the clouds.
The various zones do not run parallel to each other around the islands
and they are not the same in all areas. For example, the dry zones in
7

About the Authors
Lukas Keller is a professor in evolutionary
biology and director of the Zoological Museum
at the University of Zürich in Switzerland. He
studied evolution and inbreeding in Darwin’s
finches and mockingbirds for many years, during
which he spent many months on remote
islands in the Galápagos. In 2014 he became
president of the Swiss Association of Friends of
the Galápagos Islands (SAFGI)
Appendix
Marianne Haffner taught biology and performed
research at the University of Zürich for
many years before she became manager of the
university’s Zoological Museum. In 2012 Marianne
was heavily involved in the development
of a Galápagos exhibit designed at the museum.
Paquita Hoeck spent the first years of her
life on the Galápagos when her father was director
at the Charles Darwin Research Station.
As a PhD student in biology, she returned to
Galápagos to investigate the genetic composition
of mockingbirds on different islands.
Paquita runs the office of the SAFGI.
Ursina Koller is a teacher and biologist by
training, and works as head of education at the
Zoological Museum of the University of Zürich.
Her involvement in an exhibit about Galápagos
and a trip to the islands aroused her passion for
this unique place and resulted in her becoming
a board member of the SAFGI.
Hendrik Hoeck is a biologist and former director
of the Charles Darwin Research Station
on Santa Cruz Island. He is the founder of the
SAFGI and has been involved in conservation
efforts in Galápagos for over 30 years. As a tour
guide, he led countless groups to the islands.
153

Pinta (Abingdon)
59 km 2 , origin of Lonesome
George, no visitor site
Isabela (Albermarle)
ca. 4700 km 2 , six volcanoes, inhabited
Mangroves, scalesia, candelabra cactus
Cormorants, giant tortoises, land iguanas
Santiago (James)
577 km 2 , salt-lake crater
Pahoehoe lava structures
Mangroves, muyuyu, palo santo
Fur seals, hawks, Sally Lightfoot crab
Fernandina (Narborough)
638 km 2 , youngest island, most active volcano
Lava cactus, mangroves, saltbush
Cormorants, penguins, marine iguanas
N
Human settlement
Rábida (Jervis)
5 km 2 red sand beach
Palo santo, opuntia cactus, croton, black mangroves
Sea lions, Darwin’s finches, flamingos, white-cheeked pintails
Pinzón (Duncan)
18 km 2 , no visitor site
50 km

Appendix
Marchena (Bindloe)
130 km 2 , no visitor site
Genovesa (Tower)
14 km 2 , old shield volcano
Palo santo, croton, muyuyu
Swallow-tailed gulls, red-footed boobies, short-eared owl
Bartolomé (Bartholomew)
1.2 km 2 , dramatic volcanic formations, Pinnacle Rock
Mangroves, grey matplant, lava cactus
Penguins, reef sharks, rays
Seymour Norte (North Seymour)
1.9 km 2 , lava plateau
Palo santo trees, parkinsonia, opuntia cactus, croton
Boobies, frigate birds, land and marine iguanas
Baltra (South Seymour)
26 km 2 , airport
Reintroduced land iguanas, Darwin’s finches
Daphne Mayor (Daphne Major)
0.3 km 2 , no visitor site
Well-known for Darwin‘s finch studies
Plaza Sur (-)
0.13 km2, lava plateau
Sesuvium, Galápagos carpetweed, opuntia cactus
Land iguanas, red-billed tropicbirds, swallow-tailed gulls
Santa Cruz (Indefatigable)
986 km 2 , lava tunnels
Mangroves, scalesia, opuntia cactus
Giant tortoises, flycatchers, Darwin’s finches
Floreana (Charles, Santa María)
173 km 2 , first island colonized by humans,
Post Office Bay
Scalesia, palo santo, croton
Marine iguanas, Darwin’s finches, flamingos
Santa Fé (Barrington)
24 km 2, Tree opuntia, palo santo, saltbush
Land iguanas, sea lions, rice rats
San Cristóbal (Chatham)
557 km 2 , capital of Galápagos, inhabited
Mangroves, candelabra cacti, muyuyo
Giant tortoises, frigatebirds, sea lions
Española (Hood)
60 km 2 , old, flat island, blowhole
Parkinsonia, mesquite, saltbush
Sea lions, Galápagos albatross, boobies, mockingb
155

Appendix
SWISS ASSOCIATION
OF FRIENDS OF THE
GALÁ PAGOS ISLANDS
Support science and conservation
in Galápagos.
Become a member:
www.galapagos-ch.org
156

Appendix
UNIQUE AND BIZARRE PARADISE
The Galápagos Islands are a dream destination unlike any other
spot on earth. This book showcases the evolution and peculiarities
of this unique place, from the formation of the volcanic islands to its
colonization by plants, animals, and—more recently—humans.
Why are reptiles the largest animals on land and why are there so
few mammals? Why are so many Galápagos species found nowhere
else? And why don’t blue-footed boobies or land iguanas flee when we
approach them? The book answers these and many more questions.
Written by scientists who have lived and worked in the Galápagos,
this book shows how the islands have shaped our understanding
of evolution. With more than 330 full-color photographs and
illustrations, the reader is taken on a visual tour while learning
about the latest science and research activities that contribute to the
conservation of the islands. Plus, an illustrated guide identifies more
than 125 commonly seen species of animals and plants.
157