Isabela eps:Layout 1 - Advanced Conservation Strategies

The Thematic ATLAS
of Project Isabela
An illustrative document describing, step-by-step,
the biggest successful goat eradication project
on the Galapagos Islands
1998-2006

CREDITS
Atlas coordinator: Christian Lavoie
Editors: Felipe Cruz • Sylvia Harcourt • Christian Lavoie
Translation: Sylvia Harcourt
Graphic design: Marycarmen Moya
Original texts by: Karl Campbell • Víctor Carrion • Felipe Cruz • Christian Lavoie
Data analysis: Karl Campbell • Josh Donlan • Christian Lavoie
Cartography: Christian Lavoie
Pictures: Project Isabela •David Jiménez •Heidi Snell •Carolina Larrea •Tui De Roy•Matts Wedin •Richard Wollocombe
Other participants: Rachel Atkinson • Wilson Cabrera • Aleyda Puente
Printing: Impresora Flores
"We would like to acknowledge the vital support of the following foundations and individuals whose foresight and participation
provided critical funding throughout Project Isabela:
Galapagos Conservancy (formerly Charles Darwin Foundation Inc)
Galapagos Conservation Trust
Frankfurt Zoological Society
Swiss Association of Friends of the Galapagos Islands
Friends of Galapagos Netherlands
The Prospect Hill Foundation
The Mars Foundation
Steven Merrill
The Stewart Foundation
The Dumke Foundation
Charles and Judy Tate
Kelly and Sandy Harcourt
Greg and Elizabeth Lutz/The Lutz Foundation
Mr and Mrs Christopher Holdsworth Hunt
Mr Peter Hutley
Mr and Mrs James Teacher
Project ECU/00/G31/GEF-UNDP
We are also deeply grateful to the many individuals whose private support and encouragement sustained this extraordinary project to its
successful conclusion"
Finally our special thanks to the truly dedicated “Project Isabela Team”
The Thematic Atlas of Project Isabela is dedicated to Sven Lindblad,
Lindblad Expeditions and Galapagos Conservation Fund,
as a token of our gratitude for their continuos
support to Project Isabela.
The Charles Darwin Foundation operates the Charles Darwin Research Station in Puerto Ayora, Santa Cruz Island, Galapagos, Ecuador.
CDF is an international not-for-profit association (Association Internationale Sans But Lucratif, AISBL), registered in Belgium under the
number 371359 and subject to Belgian law. The address in Belgium is Avenue Louise 50, 1050, Brussels.
CONTENTS
The Project Isabela 5
Feral Goats in Galapagos 9
Management & Strategy 13
Results & Effort 23
Efficiency & Costs 37
Confirming Eradication & Ecological Extinction 49
Benefits 55
Publications by Project Isabela 58

Project Isabela vs Previous Projects
ISLAND SIZE (ha) COST
(2006 US$)
RAOUL*
New Zealand
PINTA
Galapagos, Ecuador
SANTIAGO
Galapagos, Ecuador
ISABELA
Galapagos, Ecuador
2,943 ha
5,940 ha
58,465 ha
458,812 ha
$
$ 3,473,068
$
$ 83,891
$
$ 5,483,373
$
$ 3,009,529
ISLAND COST/ha
(2006 US$)
RAOUL*
Making the most of every $
COST / ANIMAL
(2006 US$)
2 3
New Zealand
PINTA
Galapagos, Ecuador
SANTIAGO
Galapagos, Ecuador
ISABELA
Galapagos, Ecuador
$
1,180.11 $/ha
$
14.12 $/ha
$
93.79 $/ha
6.56 $/ha
* Parkes, J. P. (1990). Feral goat control in New Zealand. Biological Conservation 54, 335-348.
$
$
$
504.95 $/goat
1,290.63 $/goat
$
61.29 $/goat
$
47.91 $/goat

THE PROJECT ISABELA
What is PI?
THE PROJECT ISABELA
Foreword from Project leaders 6
The Project 7
5

THE PROJECT ISABELA
6
Foreword from Project Leaders
“The necessity to conserve Galapagos, Natural World Heritage” “The PI restoration plan called for helicopters to be used as shooting
platforms, species-specific trained dogs, high quality hunters
and Judas goats, and was budgeted at $8.5 million”
Felipe Cruz, Charles Darwin Foundation, Co-Director of Project Isabela
The development and successful expansion of our species has produced the secondary effect of causing the extinction of
hundreds of species, an extinction which has been unnaturally rapid. All modern vertebrate extinctions have probably
been caused by man. On oceanic islands the situation is particularly delicate. These sites represent only 7% of the earth’s
surface, and less than 10% of bird species are present on islands, but more than 80% of the birds which have gone extinct
were island forms. Of the 396 species of birds cited by IUCN as threatened, 236 (60%) are island endemics.
There are three principle causes which explain this catastrophic phenomenon 1) hunting and/or over exploitation (as in
the case of the land tortoises); 2) the impact of introduced species and 3) habitat destruction.
The rate of extinctions keeps speeding up. In conservation biology one no longer talks about avoiding the extinction of
species, but now it is a discussion as to which species can be saved. We are rather like a collective Noah, deciding with
a biblical coldness which life forms will be able to accompany us on our new journey in the Ark. The world state
continues to get worse, but in Galapagos we still have the opportunity to reverse this trend because the human presence
is fairly recent; because the impacts of the invasive species are reversible; because here we still maintain 95% of the
native and endemic biodiversity; and, because of geographical isolation, we can help to protect the area with strict
processes which make the arrival of new invasive species more difficult.
Throughout the world many plant and animal species are at a level of threat which has not been registered at any
previous moment in history. It is therefore not at all surprising that protection of the biodiversity is one of the biggest
priorities for conservation on a world level. In this context Project Isabela is an example of restoration of ecosystems on
a scale never carried out before. Until now, the conservation world thought it impossible to work on this scale. We have
achieved, in record time, the reversal of the degradation processes that were occurring on Isabela and Santiago,
improving by 60% the conservation status of the native and endemic species of Galapagos. Through the combining of
effort and knowledge and with the strengthening of local capacities, we consider that this is pioneer work and we are
sure that the possibilities of replicating it will be of help on a world scale.
We can not afford to lose even one species of our world heritage without in some manner impoverishing our society and
that of future generations. Probably the experts in conservation do agree that Project Isabela achieved the recovery of the
habitat and the protection of the species in these areas, on a scale never attempted before, through an initiative which
combined previous experiences and developed new forms of confronting problems. Even though the initial costs may
have seemed high, the final benefits are greater than the investment.
Our world heritage is not an acquired right, but an undeniable inheritance for future generations.
Victor Carrion, Galapagos National Park, Co-Director of Project Isabela, (Responsible for the Area of
Control and Eradication of Introduced Species in GNP).
The Galapagos Islands are located approximately 1,000 kms from the continent, and were formed by volcanic eruptions.
They have a land surface of 7,970 km 2 and a Marine Reserve of approximately 138,000 km 2 , and maintain an important
level of biological diversity and endemism. Of all the species identified in Galapagos (more than 5,000) about 1,900 are
endemic and 74 are threatened. The animal species most representative of the islands are the Darwin finches, the Galapagos
penguin, the flightless cormorant, giant tortoises, marine and terrestrial iguanas and amongst the plants, the Scalesia and
Miconia. 95% of the original biodiversity has still been maintained. The extinctions of mammals (various species of endemic
rice rats) which have occurred have been due principally to the effects of species (such as the black rat) introduced by man.
Of the land surface, more than 96% is protected by the State, and this was declared a National Park in 1959. In 1978 the
Park was included in the list of World Heritage Sites of UNESCO (United Nations Educational, Scientific and Cultural
Organization); in 1984 it became part of the network of the World Biosphere Reserves in the UNESCO program, Man and
the Biosphere and in 1998 UNESCO declared the Marine Reserve of Galapagos as a protected area and World Heritage Site.
This Reserve covers all the interior waters as well as extending to 40 miles around the islands measured from the most extreme
points (base line).
The arrival of man in Galapagos provoked the beginning of the progressive deterioration of the natural environment of the
islands, particularly because of the deliberate introduction of species of plants and animals for subsistence farming in these
“inhospitable” islands. The surroundings which these species found on their arrival was such that they could colonize in an
accelerated manner, escaping man’s control and becoming from then on, one of the worst threats to the island ecosystems.
The efforts which are now necessary to reverse these impacts keep increasing. In some cases the future is very bright but in
others it is very uncertain as we still do not have mechanisms and techniques to cause the drastic reductions necessary in the
populations of invasive species such as rats, cats, anis, and the plants such as blackberry, guava, cinchona and a host of
invertebrate species.
This Document; Karl Campbell, Christian Lavoie & PI Team
The Project
The Project Isabela Atlas is an illustrative document that provides a step-by-step overview of Project Isabela’s activities and
achievements. The primary role of this Atlas is to provide a visual and easy-to-read outline of the strategy, methods, results
and magnitude of the eradication challenges.
Managing a large intensive project with different methods being employed sequentially and others simultaneously was
facilitated by a geographical information system (GIS), a system that was designed and implemented for managing most of
the spatial data. This, along with a database for managing effort and kill data allowed information to be accessed in a timely
manner by managers in the field, while also forming the basis for further analyses and publications. The Atlas shows many of
the visual tools used by managers and hunters on a daily basis to facilitate their activities. These tools increased the efficacy
of the project and dramatically improved our ability to achieve concrete results.
The Atlas’s intended audience is broad, from the general public to conservation practitioners and eradication specialists.
Many of the examples included here on how we conducted various aspects of our work will not be presented visually in any
other publication. We’ve tried to make this document short and easy reading, informative, attractive and interesting. We hope
that by the time you turn the last page you will feel as excited about restoring islands as we are.
PI Background
Eliecer Cruz and Robert Bensted-Smith, directors of the Galapagos National Park Service (GNPS) and the Charles Darwin
Foundation (CDF) conceived Project Isabela as a bi-institutional initiative. Linda Cayot, then head of Vertebrates at the CDF
became the first bi-institutional leader of the Project. With this new position, Linda also inherited the ongoing Santiago pig
eradication project. In 1996 Brian Bell visited from New Zealand and put together a proposal for eradicating goats from northern
Isabela. Shocked by the $5 million price-tag, it was thought wise to invest in a more complete revision and bring in a range of
world renowned experts to develop a restoration plan. In September 1997, sixteen experts attended a workshop in Galapagos
and drafted a plan. The plan called for helicopters to be used as shooting platforms, specialist dogs, high quality hunters and
Judas goats, and was budgeted at $8.5 million. The underlying philosophy was to bring all the best methods, techniques and
tools from around the world into one project. We invested time and money into improving methods and tools that were not
efficient or yet being applied. Improvements in Judas goat methods and the application of GIS to facilitate management are
prime examples. Less than a year after the workshop Linda left the Galapagos; Marc Patry and Felipe Cruz took over and Karl
Campbell came in as volunteer for his second tour. Two years later, as Marc left, Felipe along with Victor Carrion became heads
of PI, while Karl became field operations manager and Christian Lavoie joined the team as the GIS specialist.
Santiago Pig Eradication
Pigs raided giant tortoise and sea turtle nests, preyed upon Galapagos rails and their eggs and altered vegetation for over 150
years on Santiago. A revised campaign utilizing systematic hunting of zones by hunters and dogs and the strategic use of
toxic baits ended a 30 year campaign. The last pig was removed in November 2000. In total, over 18,000 pigs were removed
during the campaign. Santiago is the largest island in the world where feral pigs have been eradicated, the second largest
island is only about half its size. Today, turtle and tortoise eggs and hatchlings, nesting seabirds such as Galapagos petrels,
and many plant species suffer no pig predation. Galapagos rails have dramatically increased in numbers, with Santiago now
being the strong-hold for this charismatic endemic species (read about the Galapagos Rail on page 57).
Pinta Goat Eradication
Within the plan to eradicate goats from Isabela was a trial to gain experience in the Judas goat method while eradicating
goats from Pinta Island. Judas goats (JG) are goats that are captured, fitted with radio telemetry collars and released. As goats
are gregarious, JG´s search out and associate with other goats. They can then be tracked down and any associated feral goats
can be removed. This method is used when goats are at very low densities, increasing the efficiency with which feral goats
can be detected by reducing search time.
Goats were introduced to Pinta in the 1950s and by the 1970s had devastated the island’s native vegetation. Goats were
removed from Pinta Island after a 30-year eradication campaign, the largest removal of an insular goat population using
ground-based methods. Over 41,000 goats were removed during the initial hunting effort (1971–82). In the following decade
the island was twice wrongly declared free of goats. During this period, the island was visited irregularly but no monitoring
program was implemented. A revised campaign over 1999–2003, which included improved hunting techniques, Judas goats
and monitoring, removed the final goats from the island.
7
THE PROJECT ISABELA

FERAL GOATS IN GALAPAGOS
Feral Goats in Galapagos
FERAL GOATS IN GALAPAGOS
Capra hircus in Galapagos 10
PI targeted islands 11
9

FERAL GOATS
IN GALAPAGOS
10
Capra hircus in Galapagos
“Nearly half of all terrestrial life forms in Galapagos
are found nowhere else on earth”
Introduced mammals are major drivers of extinction. Feral goats (Capra hircus) are particularly devastating to island
ecosystems, causing direct and indirect impacts through overgrazing, which often results in ecosystem degradation and
biodiversity loss. Goats and donkeys are the primary threat to Galapagos’ most endangered plants, and are believed
responsible for one plant extinction, an endemic from Santiago. Goats convert forest to grassland by stopping regeneration
and felling trees or girdling and killing them with their horns. In this way they eliminate entire forests and ecosystems from
islands they inhabit. Endemic birds, reptiles and other animals that rely on this habitat disappear; if these species are
restricted to those areas they are lost forever. As seen on Santiago, many palatable endemic plant species are often reduced to
individuals hanging on in inaccessible bluffs. Exclosures provide seed banks for safe keeping of these severely reduced
populations, but the threats must be removed for recovery to
occur.
Goat menace!
Removing goat populations from islands is a powerful conservation tool to prevent extinctions and restore ecosystems. Goats
have been eradicated successfully from 120 islands worldwide. With newly developed technology and techniques, island
size is perhaps no longer a limiting factor in the successful removal of introduced goat populations. Furthermore, the use of
global positioning systems (GPS), geographic information systems, aerial hunting by helicopter, specialized hunting dogs, and
Judas goats have dramatically increased efficiency and significantly reduced the duration of eradication campaigns.
Intensive monitoring programs are also critical for successful eradications. Eradication removes the entire population of a
given species from an area, compared to control efforts where a percentage of the population will be removed in perpetuity.
Eradication offers a permanent solution with a once-off investment, and given the clear biodiversity benefits, the introduced
goat populations should be permanently removed.
Because of the presence of humans with domestic goat populations on large islands, future island conservation actions will
require eradication programs that involve local island inhabitants in a collaborative approach with biologists, sociologists,
and educators.
FACT BOX
• Worldwide # of islands where goats have been eradicated: 120
• Range size of these islands: 1 to 132,000 ha
• Cumulated area of these islands: 600,000 ha
• Luxembourg = 50% of PI targeted islands
• Monaco = 0,04 % of PI targeted islands
• PI targeted islands = 20% of Massachusetts State
C. Azul
1,625 m.
TOPOGRAFIC PROFIL
Topographic profile of Isabela Island
S. Negra
1,100 m.
PI targeted islands
Pushing the limits to a total new scale
Alcedo
1,150 m.
Darwin
1,425 m.
Wolf
1,707 m.
Ecuador
875 m.
FERAL GOATS
IN GALAPAGOS
11

MANAGEMENT & STRATEGY
How it has been done
MANAGEMENT & STRATEGY
Eradication methods 14
Chronological strategy 16
Ground hunting management 18
Aerial hunting management 19
Judas goats management 20
13

MANAGEMENT
& STRATEGY
14
Eradication methods
“On large islands a range of methods used sequentially
and simultaneously are required to put all animals at risk”
Strategic use of methods
Throughout all our eradication work we followed some simple rules. Where possible as close to 100 % of the animals were
removed on their first encounter, reducing the possibility that survivors learn from their exposure to a certain hunting
method. We studied the vegetation type, topography and goat densities; and hunters’ efforts revolved heavily around
techniques to minimize escapes. For example, on Santiago mustering was used in the highlands in the first months as this
was the only practical method by which herds of thousands of animals could be removed with near zero escapes. In
eradication, efficacy (being efficient and effective) is a combination of minimizing cost per kill and maximizing the ratio of
goats killed to escapes. Each method is suited to different terrain, vegetation type and goat densities. This creates a hierarchy
of methods that can be used sequentially. The development of wary animals to any one method requires a change in
methods to place those animals at risk. In various situations it is also highly
advantageous to use different methods simultaneously.
Aerial hunting
Landscape or vegetation type offer refuge for goats from one or more
methods; however no vegetation or terrain type provides refuge for goats from
all methods. On Santiago goats found refuge from ground hunters with dogs
in lava fields, a place where aerial hunting excels. Conversely, goats found
refuge from helicopters by remaining motionless under vegetation and by
hiding under thick vegetation and in caves; these areas and tactics then made
goats vulnerable to ground hunters with dogs. On a large scale and on
complex islands, a refuge will likely exist for most methods. As such, on large
islands a range of methods used sequentially and simultaneously is required
to put all animals at risk.
Ground based mustering and corrals
In order to channel goats into corrals, we used netting strung out in large
“wings” up to several kilometers in length. This method was developed to
facilitate the removal of vast herds of goats that could not effectively be
removed by other means without significant numbers of escapes. Prior to the
arrival of helicopters this method was fundamental as an initial knock-down
tool, and was very cost-effective.
In the 1970s New Zealanders began using helicopters intensively as aerial shooting
platforms and for recovering deer carcasses for a demanding European market. Aerial
shooting is now practiced extensively in Australia and New Zealand to control feral
animals cost-effectively and on a large scale. Contrary to common belief this method is
actually endorsed by animal welfare organizations as the most humane method of
removing feral goats in rough terrain. It is highly effective in sparsely vegetated areas or
areas with trees with open canopy; the majority of Isabela and large tracts of Santiago
fit this description. Aerial shooting is cost-effective at high and low animal densities and
allows for the rapid coverage of large areas.
Ground hunting
Traditional hunting, or, as we’ve dubbed it, free hunting, involves individual or pairs of
hunters with or without their dogs hunting freely within a zone. This allows hunters to
concentrate their efforts and use various hunting tactics in areas where goats are frequent,
such as hill-tops, rocky ridges, cliffs, craters and lines of caves. This method
is most efficient when goats are at high, medium and low densities. Skilled and motivated
hunters are required. Large areas can be effectively covered with multiple camps of 2-3
hunters spaced throughout.
Mata Haris is a line-hunting technique adopted and improved from our local hunters and
conservation practitioners in New Zealand. The technique involves a team of hunters
working at fixed spacing (100-150m) and systematically moving through an area, typically
proceeding into or perpendicular to the prevailing wind. Hunters maintain their place in
the line by radio communications and hand-held GPSs with pre-determined points from
the GIS. In this way, we produced a coordinated wall of hunters and dogs optimally spaced
and covering swaths typically 3 km wide. This method is ideal for detecting animals at very low densities and covering areas
systematically; it ensures that all areas are covered, and even the most wary animals are at risk. Deployment/retrieval of
hunters and dogs by helicopter allows them to work remote areas and still remain ‘fresh’ for when goats are detected.
Dogs
Eradication methods
“On large islands a range of methods used sequentially
and simultaneously are required to put all animals at risk”
New Zealand is the only country in the world where specialist goat dogs are
employed by many hunters, providing breeds that facilitate training of pups due
to natural instincts. A core breeding and training stock of five dogs was imported
from New Zealand in 2000 and specialist dog trainers from there were employed
to train hunters and develop trainers and a team of specialist goat dogs. Other
hunting dogs from the Galapagos were selected for skills missing in the imported
team and a team of over 70 skilled dogs was developed within 2.5 years.
Certification at basic and advanced levels maintained dogs at high standards,
and aversion training was conducted to ensure dogs were species specific and showed no interest in native wildlife. Hunters
would work with one or two dogs each. Dogs were finder-bailers (dogs that track, find and contain the goats while waiting for
the hunter to arrive), and could typically work with ground and air scents to detect and find goats. Dogs are highly effective with
small groups of goats at low densities. They perform well in dense vegetation where other methods are ineffective, making them
a key element when confronted with vast areas of that vegetation.
Judas goats
Goats are highly social and gregarious animals; they have an aversion to
isolation, and will seek out others when isolated. The Judas goat method
exploits these elements of goat biology to increase the cost efficiency of
control and eradication operations when animals are at low densities. Judas
goats are selected, captured, fitted with radio telemetry collars and released.
They can then be tracked down and any associated feral goats will be
removed. The Judas goat method is used as an accessory to other hunting
methods, being most commonly used in conjunction with aerial hunting by
helicopter and ground hunting with and without dogs.
Judas goats increase the efficiency of removing animals at low density by reducing search time for hunters locating remnant
herds or individuals. However, we discovered on Pinta that current Judas goat methodology fell short of its potential efficacy.
The ideal Judas goat would search strongly for goats, be searched for by other goats, be sterile and not become wary. Reasons
that goats may search for conspecifics include isolation and sexual cues. To maintain Judas goats in a state of isolation,
managers in addition to shooting feral goats, shoot or capture any additional Judas goats associated with a particular Judas
goat. Sexual cues involve both sexes searching strongly for mates, particularly when females are in estrus. Females in estrus
actively search for males and likely attract them using pheromones. We developed protocols to sterilize, terminate pregnancy
and induce female goats into a prolonged estrus with hormone implants. We then compared the efficiency of three types of
Judas goats; sterile male, sterile female and sterile females in a prolonged estrus which we have dubbed Mata Haris (after the
seductive and lethal World War I double agent).
MANAGEMENT
& STRATEGY
15

MANAGEMENT
& STRATEGY
16
Chronological strategy
Santiago
The Project Isabela transitioned from pig monitoring to goat eradication on Santiago Island in December 2001. Delays in
gaining access to funds and initiating contracting procedures for helicopters and other equipment forced us to look at
other alternatives on where to have dogs and hunters working. Santiago filled that role; infrastructure in the form of trails and
huts were already present and the hunters knew the island intimately. Santiago served as a training ground for dogs and
ground hunters alike, allowing techniques to be refined and developed to suit our needs and the environmental conditions.
Mustering into corrals by hunters on foot and on mules was used as an initial knockdown technique. This was followed by
free hunting with dogs in all areas of the island. Ground hunters worked intensively; 85 trips were completed during the goat
eradication with a peak of 21 trips in 2004. Trips averaged 2 weeks and typically involved 12-15 ground hunters with 2 dogs
each. Up to 50 ground hunters and over 100 dogs were on the pay-roll at any one time in the first two years. In 2003, 18
trips focused efforts on the densely vegetated area of Santiago. This strategy was adopted because helicopters, once they
arrived, could quickly remove the bulk of the remaining population on the rest of the island and this area would remain the
hardest part of the island from which to remove goats. Ground hunters removed 73,151 goats before helicopters came on the
scene in February 2004; by the end of March another 12,912 goats had been removed, along with the last donkeys. The
effectiveness of aerial hunting was apparent. Ground hunters and aerial crews had removed 99% of the goats; the remnant
animals were wary of both methods, and a new technique was required to boost efficiency. In June, 122 Judas goats were
systematically deployed on Santiago, followed by another 90 in December. Judas goats were initially checked by ground
hunters with dogs, while in March 2005 aerial checks began. In August 2005 few goats were thought to remain; ground
hunters with daily aerial support started systematically monitoring the island, working in rastrillo. The last feral goats were
removed by ground hunters in November and at the end of the month all Judas goats were removed from Santiago. This
assisted ground hunters and their dogs; any goat sign encountered would be from feral goats. Systematic sweeps continued
until March 2006; no goat sign was detected. Santiago Island is now goat free for the first time in at least 80 years. At the end
of March 2006, 20 Judas goats were deployed to monitor any deliberate goat re-introductions to the island.
Timeline
FACT BOX
• Duration: 5 years and 4 months
• Goats removed: 89,474
• Hunter hours: 65,031
• Dog hours: 85,510
• Helicopter hours: 921.6
• JG deployed: 232
• Days with Judas goat presence (up to March 31st 2006): 653
• Hunter accidents: 1 broken leg due to a horse kick!
6 knee & 1 ankle problem with surgical intervention
Chronological strategy
The sound of rotor blades turning over Isabela in April 2004 signaled the start of a massive campaign. Aerial hunting crews
had refined techniques on Santiago that ensured that escapes were minimal (e.g. helicopter crews were often deployed to
shoot goats spotted seeking refuge in caves). Aerial hunting began on Wolf and Ecuador volcanoes, then rolled south to
Darwin and Alcedo. The initial knockdown took seven months, resulting in 55,575 goats being removed, and donkeys being
eradicated on Alcedo volcano. This phase was interrupted by a helicopter accident in June 2004; fortunately no one was
injured but the aircraft was a write-off. Isabela was largely an aerial operation with limited but strategic use of ground hunters
and dogs; only 7 trips were conducted, the majority of which were in densely vegetated areas. Vegetation consisting of a
canopy of trees and lower vegetation forming an additional under canopy reduced visibility of goats from the air. Aerial
hunting removed the bulk of the animals but ground hunters demonstrated the efficiency of that method in near ideal
conditions with goats that were naive to ground hunters and dogs. By December 2004 goats were at low densities. Over the
next three months some 700 Judas goats were deployed on the northern and southern part of Isabela. A further 70 Judas goats
were deployed in late 2005 on the remainder of southern Isabela. On this island, Judas goat monitoring was conducted
exclusively by helicopter. Twelve months of intensive Judas goat monitoring was conducted; 915.7 accident free flying hours
resulted in 7,363 checks, 1,236 recaptures and redeployments and 4,524 feral goats removed. Northern Isabela is now free of
feral goats; the last goat was removed from Alcedo in December 2005. Southern Isabela has been controlled to extremely low
numbers; possibly 20-30 animals remain. Operations finished at the end of March 2006. 266 Judas goats were left as their
removal would be expensive. As they are sterile there is no risk of repopulating the island and they may be useful for future
monitoring efforts.
Timeline
FACT BOX
• Duration: 2 years
• Goats removed: 62,818
• Hunter hours: 5,161
• Dog hours: 8,877
• Helicopter hours: 2,320
• JG deployed: ~700
• Days with Judas goat presence (up to March 31st 2006): 465
• Accidents: 1 heavy landing and 1 emergency landing w/o tail rotor blade control.
Isabela
MANAGEMENT
& STRATEGY
17

MANAGEMENT
& STRATEGY
18
Ground hunting management
Santiago: ground hunter land
Massive areas made manageable
At 58,465 ha Santiago Island is more than 3 times the size of
Washington DC; it is too large for ground hunters or even a
helicopter to work as a single block. The island has no roads or
fences and is over 35 km long and 21 km wide. The division of the
island into 24 blocks for ground hunters allowed the entire island to
be worked systematically. Satellite imagery was used to assess the
island geography; wavelength band combinations were used to
highlight vegetation types and volcanic areas. GPS units were used to mark existing trails throughout the island. Natural
topographic features, easily identified by hunters (e.g., ridgelines, hills, etc), were also identified. Ground hunting blocks
were subdivided into a total of 137 sub-blocks which facilitated the specialized rastrillo ground hunting technique and
provided optimally sized areas for teams of 15 hunters to cover in one day. Sub-blocks in open areas were on average twice
the size of the Principality of Monaco (384 ha) and those in heavily vegetated areas were about 171 ha.
FACT BOX
• Ground hunters: 100% Galapageños
• 20% from Isabela, 80% from Santa Cruz
• Highly qualified hunters
- Hunting skills
- GPS handling
- Rifle maintenance
- First aid intervention training
• 147 dogs bred in PI kennel
• 2 qualification levels for dogs
Dogs wearing special leather boots for protecting their
paws when working on lava during hot days.
Not Welcome
While Santiago Island has a good network of trails, several camps
and water collecting sites, Isabela Island is far from providing the
same level of hospitality. Moreover, a large proportion of the island
is covered by lava fields and thus large areas of the island are not
practically workable from the ground. Size, remoteness and
complex access are additional factors that make Isabela a difficult
island to work on.
Darwin volcano is a good example. Probably the driest of all,
it has around 64% of its area covered by volcanic rocks. Wolf with
its steep slopes and high altitude also offers a big challenge.
Alcedo presents probably the best conditions as well as having a
hut and water collector on the rim. The Linda Cayot hut is
accessible by a moderate climbing trail. The southern part of
Isabela, even though it has existing trails and a National Park hut,
offers a challenge, not only because of its size, but also because of
the huge lava fields.
For all these reasons, helicopters were chosen and have proven to
be the best hunting and monitoring tool for tackling Isabela Island.
Aerial hunting management
FACT BOX
Isabela: helicopter land
• Helicopter model: MD500D/MD500E
• Capacity: 1 pilot and up to 3 passengers
• Airspeed: Hover to 156 knots
• Range: 225 Nautical miles ~2.2 hours @110 knots
• Lifting capacity: 500kg
MANAGEMENT
& STRATEGY
19

MANAGEMENT
& STRATEGY
20
Judas goats management
Releasing Judas goats
Deploying Judas goats
Judas goats for Santiago were captured on Isabela and
underwent quarantine procedures before being transported
by boat to sites (Puerto Nuevo and La Bomba) for loading
into the helicopter. Quarantine is a common procedure
when traveling between islands to prevent foreign species
from being transported from one island to another, in this
case in particular seeds in the stomach, hair or hooves.
Deployments were conducted systematically by flying a
load of 10-12 Judas goats and deploying them at
predefined locations that were 2.25 km apart in vegetated
areas and 3 km apart in lava areas. Flight paths for
deploying each load of Judas goats were planned to
minimize flight time. The map of Santiago shows each
load of Judas goats in a different color, with the
helicopter’s GPS tracks. Each load of Judas goats took
around 30 minutes of flight time to deploy. On Isabela
Island, 700 Judas have been deployed on the northern and
southern parts at similar spacings, using the same
deployment strategy as Santiago.
FACT BOX
• >700 Judas deployed
• 33% males
• 33% females
• 33% Mata Haris
Making Judas goats more efficient
From feral to Judas: 9 steps
Project staff implemented new techniques to maximize the efficacy of their Judas goats.
Goats were sterilized, pregnancies were terminated by a hormone injection and Mata
Haris were females implanted with hormones to induce a prolonged estrus effect.
Sterilization techniques were selected to maintain normal hormone levels in males and
females to ensure no alteration in their behavior. Males were sterilized with a technique
similar to a vasectomy, while the fallopian tubes were tied in the females.
1. Capture 2. Injection to terminate pregnancy
3. Ferry to camp
4. Ear tagged & quarantine
(if going inter-island)
5. Sterilization procedures
6. Hormone implant for Mata Haris
7. Collared 8. Loaded
9. Deployed
FACT BOX
• 600 telemetry collars
• Frequency range: 170-174MHz, with transmitters
at 10KHz spacings
• Weight: ~400 g.
• Battery: Lithium with ~5 year life
• Activation: with magnet swipe over a reed switch
• Signal – line of sight: typically up to 6 km on ground,
and up to 50 km from helicopter
• Color: Day-glow orange
Maps: a daily tool for monitoring
Helicopter crews monitored Judas goats intensively. Maps with the last
position of each Judas goat were provided to crews and updated daily. Maps
indicated the unique ear tag number and collar frequency of each Judas goat
and allowed crews to effectively manage over 600 goats. Judas goats need to be
kept alone to maintain their searching behavior. When Judas goats were found
together (see Association potential situation), all goats apart from one were
captured and re-deployed (see Action Taken potential situation). Maps
identified areas that Judas goats had moved out of, providing an indication of
where to re-deploy captured Judas goats.
Event (or collected) information:
• Date
• Ear tag
• Geographical position (GPS)
• Association (see box)
• Action taken (see box)
• # Goats removed
Judas goats management
Monitoring Judas goats
ASSOCIATION
with ferals & Judas, with Judas, with ferals, alone
ACTION TAKEN
Kill, Freed, Capture/translocated, Found dead, Escape/Not found
MANAGEMENT
& STRATEGY
21

RESULTS & EFFORT
What has been done
RESULTS & EFFORT
Before & after: Santiago 24
Santiago 25
- Ground hunting phase
- Aerial hunting phase
- Judas phase
Isabela 29
- Aerial hunting phase
- Ground hunting phase
- Judas phase
Judas goats´ movements 33
- An example
Before & after: Isabela 34
23

24
Before & after: Santiago
Vegetation recovery in the highlands
March 1999
March 2005
Tremendous ground hunting effort was invested on Santiago Island between
December 2001 and June 2004. The northern side of the island shows the high
numbers of goats that have been eradicated. Added to this are the results obtained doing
mustering and corrals which were not included in the final block results.
Despite the fact that the spatial dimension has always been taken into account for work
planning, early data were not gathered using a methodology that could be integrated in
the GIS and thus are not on the map; a lesson learnt throughout the project.
Not on map:
• 22,732 goats
• 21,221 mustering hours
FACT BOX
Approximate distance walked
by hunters
• Total hunting: 26,725 km
- 2001: 880 km
- 2002: 7,656 km
- 2003: 12,100 km
- 2004: 6,089 km
Time worked
• Total hunting: 44,207 hrs
- 2001: 7,060 hrs
- 2002: 12,844 hrs
- 2003: 16,927 hrs
- 2004: 7,376 hrs
Santiago: ground hunting phase
Yearly results per method
Learning while eradicating
Mustering & corrals:
1 : 2,600 goats, 238 hrs
2 : 1,224 goats, 224 hrs
3 : 3,000 goats, 420 hrs
4 : 290 goats, 168 hrs
5 : 40 goats, ~300 hrs
6 : 2,500 goats, 420 hrs
7 : 235 goats, 60 hrs
8 : 1,500 goats, 1071 hrs
Hunters walked the equivalent of 67% of the earth’s
circumference during the hunting phase.
25
RESULTS & EFFORT

RESULTS & EFFORT
26
Santiago: aerial hunting phase
Hunting effort
Interpreting helicopter movements on Santiago
The GPS track from helicopter operations on Santiago during the hunting phase shows where effort was focused. Goats were
easily detected and frequented the edges of lava flows; these areas were regularly flown and many goats were eliminated. Other
landscape features that goats frequent, such as hills and lines of caves, can also be seen as concentrations of hunting activity.
FACT BOX
Hunting km flown
• 19,687 km total (Quito to Kuala Lumpur, Malaysia)
- 18,708 km in 2004
- 979 km in 2005
Hunting hrs flown
• 271.8 hrs total (11.3 days non-stop)
- 262.6 hrs in 2004
- 9.2 hrs in 2005
Tracking down the machine!
The helicopter’s GPS was programmed to log
a point every 20 seconds, from which the
flight track is constructed. After downloading
GPS data these points are joined together in
their time sequence to provide a track,
represented as a line on a map.
Helicopters at work!
Pin-pointing the goats
Santiago: aerial hunting phase
Hunting results
On Santiago, two helicopters were used intensively. Within two months nearly 13,000 goats were removed. A combination of
ground hunters with dogs working the densely vegetated southern slope and the simultaneous use of helicopters working the
remainder of the island was highly effective. With combinations of methods such as these, the population was quickly driven
to zero. As goat numbers decreased, Judas goats were introduced to increase the efficiency of ground and aerial hunters
because of reduced search time.
FACT BOX
Period: February to March 2004
• 12,912 goats eradicated
• 15% of total goats eradicated
• 94% eradicated 0-500 m. alt.
• 6% eradicated >500 m. alt.
Highest densities of goats were
encountered in dry open and scrub areas.
Each helicopter and ground hunter had a GPS to allow managers to see that all areas of the
island had been covered and where goats had been killed or escaped. This spatial information
was used in determining when changes in methods were required. The dots on the map show
GPS waypoints where groups of goats were shot by aerial hunting crews. Manual counters were
used by shooters to record the number of goats shot, allowing us to later calculate the number of
goats killed per waypoint.
27
RESULTS & EFFORT

RESULTS & EFFORT
28
Santiago: Judas phase
Judas goats strategy outcomes
FACT BOX
Helicopter facts
• 13,390 km flown of which:
- 2%(2004), 97%(2005), 1%(2006)
• 9.6 days non-stop equivalent
Ground facts
• August 2004 to July 2005
• 14 trips
General facts
• 913 Judas released on checks
• 284 Captured & translocated
Judas goats on Santiago
Judas goats were monitored by ground and aerial
hunting crews on Santiago about 1,400 times.
Ground hunters invested 5,010 hours and dogs
7,720 hours, while 231 helicopter hours were
flown. Kills in this phase accounted for 1% of all
goats killed on Santiago. Some 617 goats were
killed associated with Judas goats; 319 and 298
were killed by aerial and ground checks respectively.
A further 557 goats were killed unassociated with
Judas goats; 97 and 460 were killed by aerial and
ground checks respectively. On average, ground
hunter checks were nine times more expensive than
helicopter checks. However, as dogs detected more
goats that were not associated with Judas goats, the
final costs per goat killed during this phase were
almost identical for helicopter and ground crews.
Group sizes of goats killed during the Judas goat
phase on Santiago. Purple dots indicate feral goats
killed that were not associated with Judas goats. Pink
dots are feral goats that were shot while associated
with Judas goats.
Ideal helicopter country
Isabela: aerial hunting phase
FACT BOX
Hunting results
On Isabela, helicopter crews removed 98% of all goats; the terrain and vegetation was, in general, ideal for aerial hunting.
Goats were shot on all volcanoes, with the highest densities occurring on Alcedo, Darwin and Wolf. Aerial hunting was
extremely efficient and allowed areas to be covered that would have been near impossible to cover by foot. One area
proved difficult to hunt from the air. Dense vegetation on the southern slopes of Alcedo was hunted intensively but many
animals still remained. Goats altered their behavior, becoming motionless and hiding under vegetation where they were
generally safe from detection by aerial crews. Methods were switched after aerial hunting had removed all the animals
possible (read further p.30).
Period: May, June & December 2004 + January
to March 2005
• 56,657 goats eradicated
• 98% of total goats eradicated
• 46,664 in 2004 & 9,993 in 2005
• 54% eradicated 0-500 m. alt.
• 33% eradicated 500-1000 m. alt.
• 13% eradicated > 1000 m. alt. & inside craters
* Unlike on Santiago Island, no black goats were seen
on Isabela Island
Hunting km flown
• 72.761 km total (1.8 times the earth’s circumference)
• 43,957 km in 2004
• 27,533 km in 2005
• 1,271 km in 2006
Hunting hrs flown
• 1,258 hrs total (52.4 days non-stop)
• 930 hrs in 2004
• 312 hrs in 2005
• 16 hrs in 2006
Tracking on down Isabela
With Santiago’s recent experience fresh in their
minds, the helicopter crews were well prepared
when they arrived on Isabela. After a general
orientation flight aimed at identifying some of the
goat’s living areas, the hunting phase was
launched. A whole month based on volcano Wolf
enabled them to work the northern part of Isabela
thoroughly, flying more and spending more time
than originally planned due to the unexpected
high number of goats.
After being based at a temporary camp
on northern Isabela, the group then
moved to the permanent camp where
they were based until the end of March
2006; Cowley base in Alfaro Point, on
the eastern side of Isabela. From there,
work was targeted on Alcedo and
Darwin. Alcedo stands out as the
problematic volcano as it had the
largest goat population. Hunting flying
time and kilometers flown are on a
different magnitude than any previous
job! The flying tracks on the map show
how all of Alcedo area is suitable for
goats, as opposed to any other volcano
where more lava areas restrict the
populations into the smaller reduced
vegetated regions.
29
RESULTS & EFFORT

RESULTS & EFFORT
30
Isabela: ground hunting phase
Ground hunters to the rescue
A strategy for dense vegetation
Aerial hunting removed 6,077 animals from Alcedo’s densely vegetated southern slope (see zone of interest in the map). The
remaining goats had become wary of this method and kill rates dropped to 1.5-2 goats per flight hour. In anticipation, ten
water catchments were set up at 3 km intervals throughout this zone. Groups of 2-3 hunters and their dogs were based at
water catchments for 12 days for three consecutive trips.
Hunters´ tracks Goats killed
First trip in January 2005: 3.6 goats per hunter day
Second trip in February 2005: 0.7 goats per hunter day
The images below show hunters’ GPS tracks and positions of goats killed. The second and third trips killed approximately
one-tenth the number killed the previous trip. Aerial hunting was simultaneously conducted around this zone, removing
goats attempting to flee the area. At the end of the third trip Judas goats were deployed in this area.
“Water catchments”
Hunters´ tracks Goats killed
Third trip in June 2005: 0.07 goats per hunter day
31
RESULTS & EFFORT

RESULTS & EFFORT
32
Isabela: Judas phase
Judas goats strategy outcomes
Judas goats on Isabela
After having refined their techniques on Santiago for Judas goat capture, sterilization, deployment and tracking, Isabela,
although much larger was in many ways simpler, as teams knew their roles and were highly efficient. Prior to Santiago the
world’s largest Judas goat operation involved around 30 Judas goats, and this was the Judas goat facilitated eradication on
Pinta. The scale at which the campaign was now being conducted was by all standards massive. A database specifically
designed for keeping track of Judas goats kept our GIS specialist and one data entry person occupied; daily entries of more
than 60 Judas goat checks, associated kill and GPS data were not uncommon (see p.21 for information collected in Event
information box). Aerial crews were also busy, often daily capturing and re-deploying more than 10 Judas goats, with a
maximum of 38 in one day. In total 591 Judas goats were checked 5470 times; 3439 goats were shot associated with these
Judas goats, while 1085 were shot but not associated with a Judas. A high proportion of the last goats removed were females
with juvenile kids. Some females will go solitary to give birth and then remain alone with their kids until they become
sexually active again. These females and their kids will typically not be detected by Judas goats until these kids are sexually
mature. Judas goat campaigns must incorporate this factor into their planning. Mata Haris associated with more feral males
than female or male Judas goats (see graph). However, overall there was no statistical difference in the overall number of
goats that each of the three types associated with. In future
campaigns the intensive use of Mata Haris may assist in removing
males at a fast enough rate so that breeding does not occur with the
last females, as was seen on Santiago.
FACT BOX
Helicopter facts
• 78,311 km flown of which:
- 20%(2005) and 80%(2006)
• 38 days non-stop equivalent
Group sizes of goats killed during the Judas goat phase on Isabela. Blue dots indicate feral
goats killed that were not associated with Judas goats. Red dots are feral goats that were
shot when associated with Judas goats.
Mata Hari JGs performed ~1.5 times better than female or male JGs
at detecting feral males, while there was no difference in the
probability of any JG type detecting females.
Walking the distance!
Judas goats´ movements
An example
Monitoring Judas goats gave crews and managers detailed insight into the movements, preferred location and abilities of
goats. The original plan to eradicate goats from northern Isabela assumed that the Perry Isthmus could be used as a barrier
to immigration from the south. Monitoring Judas goats on Isabela soon dispelled that idea; some goats repeatedly traveled
45 km from the north of Wolf volcano to Alcedo, typically in 10-12 days. The majority of Judas goats averaged 3.6 km
movements between checks; only 8% of movements were greater than 10 km. Notice that these linear distances between
checks don’t take into account the sinuosity of JG movements. Judas goats provided a worst case scenario that couldn’t be
ignored. To compensate for the wrong assumption that goats could be held at the Perry Isthmus, it was decided to expend as
much extra effort as possible in driving the southern goat population towards zero. Ever-dwindling helicopter hours were
finely balanced between checking Judas goats on northern Isabela and Santiago, moving ground hunters and extending
hunting and Judas goat zones into the remainder of southern Isabela. The buffer zone (Perry Isthmus south of Alcedo
volcano) that had been assumed could prevent immigration from the south, turned into an intensive aerial hunting zone,
followed by the deploying and monitoring of Judas goats in the few months left. The population was driven to extremely low
levels but eradication in this short time was unlikely. However, the measure was primarily carried out as a way of
maintaining the results achieved in the north.
Perry Isthmus
33
RESULTS & EFFORT

34
Isabela before...
Already reversing the situation!
Volcano
1977
1997
... and Isabela after
Already reversing the situation!
Alcedo
2006
2006
35

EFFICIENCY & COSTS
Investing time and $
Efficiency of operations 38
- Aerial hunting
- Aerial monitoring
- Comparison of phases
Costs of operations 43
- Aerial hunting
- Aerial monitoring
- Ground monitoring
EFFICIENCY & COSTS
37

EFFICIENCY & COSTS
38
Efficiency of operations
Aerial hunting phase
The maps on these pages (38-39-40-41) show spatially where effort has been invested, where goats were removed
and how much effort it took to remove each goat (refer to titles). The blocks shown here were used by managers to
delineate hunting units for aerial hunting crews. Color coding shows these values; white represents the average value,
cold colors (blues, purple and light green) represent below-average values while warm colors (reds and oranges) show
above-average values. Grey areas indicate where there are no values. Standard deviation (STD) values from each data
set are the increments used to guide each color or value change. Pages 38 and 39 show the aerial hunting phase. The
following pages (40 and 41) present the aerial monitoring phase. All data sets values are normalized to the size of the
hunting blocks (ex.: Effort = time flown/ha or Animals removed = animals/ha).
EFFORT
ANIMALS REMOVED
Cowley Camp
Cowley Camp
La Bomba
La Bomba
Effort
This map shows where flight hours were invested.
The presence of helicopter base camps at La Bomba and
Cowley show high flying hours due to ferry time over those
blocks to get to any other block.
Animals removed
Alcedo had high densities of goats removed, while vegetated
areas on Darwin and Wolf volcanoes had medium densities.
On Santiago, arid areas had medium densities, while the lava
field and dense vegetation had lower numbers removed by
aerial hunting. Areas of dense vegetation on Santiago were
primarily searched by ground hunters with dogs, and the
animals removed from there are obvioulsy not shown on these
maps for aerial hunting.
Goats per unit effort
As a measure of efficiency we refer to animals removed per unit effort. This is calculated by dividing the number of animals
removed by the number of hours invested.
This map shows the relative number of animals removed per unit of effort (e.g. per hour of aerial hunting). Note that areas
where camps were based have lower values (blue), this is an artifact of helicopter ferry time over these areas to reach other
blocks. Some areas had few goats; effort invested searching for them produces dark blue areas, as seen on the majority of
Cerro Azul in south-western Isabela. Areas where high densities of goats were removed with little effort that weren’t in flight
paths (between camps or to other hunting areas) are shown in red. These areas often coincide with vegetation that was
open, allowing for aerial hunting to be highly efficient in detecting and removing animals.
GOATS PER UNIT EFFORT
Cowley Camp
La Bomba
39
EFFICIENCY & COSTS

EFFICIENCY & COSTS
40
Efficiency of operations
Aerial monitoring phase
EFFORT
ANIMALS REMOVED
Cowley Camp
Cowley Camp
La Bomba
La Bomba
Effort
Helicopter flying time expended was influenced by two
primary factors; the number of Judas goats present in that area
and the frequency at which they were checked. These factors
were influenced to some degree by the density of remnant
animals; managers concentrated more effort in areas with
higher densities of goats.
The Cowley base camp block has an inflated effort due to
ferry time. On Santiago, Puerto Nuevo acted as a refueling
site during this phase, influencing the amount of effort
expended there.
Animals removed
Management actions, such as not hunting intensively on the
western slopes of Alcedo during the aerial hunting phase to
facilitate later capture of Judas goats, influence the number of
animals removed during monitoring phase. On southern
Isabela, little aerial hunting was conducted prior to the
monitoring phase. Other areas with refuges, such as networks
of caves and lava tubes, allowed goats to remain at higher
densities during the aerial hunting phase; these animals were
then detected and removed during the monitoring phase.
Goats per unit effort
Goat per unit effort shows where remnant goats survived the initial knockdown phase, or reflect the management regimes.
For example, on the western slopes of Alcedo goats were not hunted intensively during the initial aerial hunting phase so that
this area could provide a later source of Judas goats. All of southern Isabela was hunted during the monitoring phase; kills
shown reflect the entire population rather than remnant populations. Due to management decisions, relatively large numbers
of animals were removed from the rest of Alcedo and a lowland section of Sierra Negra in southern Isabela in this phase (see
Results & effort section, p32).
GOATS PER UNIT EFFORT
Cowley Camp
La Bomba
41
EFFICIENCY & COSTS

EFFICIENCY & COSTS
42
Efficiency per phase
Aerial efficiency ratios
When should methods change? When
one method becomes inefficient or is
resulting in unnecessary escapes then
methods need to be modified or
changed. The map to the left compares
aerial efficiency (kills/flight hour) during
various phases of the campaign: aerial
hunting phase (broken down in three
stages: first 2 hours, last 2 hours and
overall) and Judas phase. Efficiency
clearly goes down from the first 2 hours,
to the last 2 and finally to the Judas
phase. The yellow line indicates 20
goats/hour, a point used to provide a
rough indication that Judas goats may
soon need to be released. Note that the
2 last aerial hunting hours refer to the
hours before changing to Judas phase
and thus are always around the 20
kills/hour mark. Ground hunting was
conducted again when goats were below
this level.
In blue: efficiency ratio between the
beginning and the end of the aerial hunting
phase. A longer bar expresses how much
more efficient (in terms of animals killed per
hour) were the first hours of the hunting
phase versus the last hours during the same
phase.
In red: efficiency ratio between aerial
hunting phase and Judas phase.
A longer bar expresses how much more
efficient (in terms of animals killed per hour)
was the hunting phase versus the Judas
phase.
The graphs confirm a ratio that had
been anticipated.
Yellow line: a visual mark that represents a
4-fold magnitude in the ratio scale, shown
to help comprehension of the graphs.
Costs of operations
Overall budget
The Santiago and Isabela campaigns were conducted together. Santiago was a training ground where methods were
refined, dogs were trained and experimental approaches taken. Overall efficiency there was lower, giving elevated costs
for that campaign and lower costs for the Isabela campaign. Once teams reached Isabela they were highly experienced,
efficient and were dealing with naive animals. By combining both campaigns we benefited from economies of scale.
Santiago Judas, 8%
Isabela Ground, 6%
Project Isabela´s overall allocation of expenditures
Isabela Judas, 17%
Santiago Corrals, 3%
Santiago Aerial, 4%
Isabela Aerial, 15%
Santiago Ground, 47%
43
EFFICIENCY & COSTS

EFFICIENCY & COSTS
44
Costs of operations
Aerial hunting phase
The following maps use 150 ha polygons, within which effort (i.e. the number of animals removed and the number of
animals removed per unit effort) is shown. Effort is expressed in $ which is calculated from known costs per helicopter
flying hour. These blocks were not used by management to delineate hunting areas, but are shown in this form to remove
biases in block size and management boundaries. Aerial hunting was conducted intensively throughout areas with highmedium
goat densities. Santiago had high densities of goats with a large number of caves and dense vegetation patches in
which they would take refuge; costs were on average 2.3 times higher per hectare for Santiago. Some areas that were
suspected to have no goats, such as south-western Isabela, had no aerial hunting activities conducted; monitoring with Judas
goats was the first method employed in these areas.
Spatial repartition of aerial hunting $ spent
FACT BOX
Cost per helicopter flight hour: $1,252
• Santiago
- Aerial hunting cost: $360,954
(7% of Santiago operation)
- Aerial hunting cost per ha: $6.17
• Isabela
- Aerial hunting cost: $1,212,572
(35% of Isabela operation)
- Aerial hunting cost per ha: $2.64
Some areas were flown that resulted in no kills (magenta areas) but these were
essential to provide effective coverage of the island during this phase.
Cheap or expensive goats?
Costs of operations
Aerial hunting phase
FACT BOX
• Santiago
- Aerial hunting cost per goat: $30*
• Isabela
- Aerial hunting cost per goat: $20*
* aerial operation cost / # goats
Results have been compiled on the basis of and homogenous
matrix of 150 ha hexagons to show a more realistic situation.
Compilation of the helicopter managing blocks would not have
provided the same visual effect (see managing blocks page 19).
45
EFFICIENCY & COSTS

EFFICIENCY & COSTS
Costs of operations
Aerial monitoring of Judas
These maps show where helicopter effort was expended and translate this effort into dollars. On the left the cost of
checking Judas goats is shown spatially; grey areas had Judas goats deployed in or near-by, and although no monitoring
events were conducted there, this ensured complete coverage of the island. The map on the right provides cost per kill for
feral goats removed that were associated with Judas goats, providing a function of cost expended and the number of feral
goats removed. Although many polygons indicate that no goats associated with Judas goats, these checks are required to
ensure systematic and complete coverage of the islands.
FACT BOX
• Santiago
- Cost per Judas check: $207.52
- Average cost per feral: $569
• Isabela
- Cost per Judas check: $191.37
- Average cost per feral: $308
Costs of operations
Ground monitoring of Judas
Ground hunters were also used to check Judas goats on Santiago. Costs per Judas goat check were nine times higher for
ground hunters than for checks by helicopter. However, ground hunters removed significantly more goats unassociated
with Judas goats between checks; when this is taken into consideration then cost per goat removed between the two methods
is comparable. Additionally, ground hunters would take more than a month to check all Judas goats on Santiago, while a
helicopter would check all Judas goats in 2-3 days. The speed at which Judas goats can be checked influences how many
goats can be removed and thus affects the potential reproductive capacity of the remnant population. By removing goats
faster, the end result is that there are fewer animals to be removed. Cost/goat removed does not take these factors into account.
46 47
FACT BOX
• Santiago
- Cost per Judas check: $1798.77
- Cost per feral: $595
EFFICIENCY & COSTS

CONFIRMING ERADICATION &
ECOLOGICAL EXTINCTION
Achieving our goals!
CONFIRMING ERADICATION
& ECOLOGICAL EXTINCTION
Santiago 50
Isabela 52
49

CONFIRMING ERADICATION
& ECOLOGICAL EXTINCTION
50
Santiago: searching for the last goats
Systematic monitoring
Monitoring Santiago
In August 2005 few goats were thought to remain on the island and ground hunters initiated systematic rastrillo sweeps of all
vegetated areas of the island. Twelve trips were conducted with up to 26 hunters and 64 dogs per trip. Nearly 12,000 hunter
hours were invested covering around 10,000 km. Three complete sweeps of the island were conducted; areas where goats
were shot on the first and second sweeps were covered several times. To maintain hunter morale, increase efficiency and to
increase the speed at which the island could be covered, ground hunters and dogs were moved daily by helicopter.
Aerial support of ground hunters
Helicopter logistical support of ground hunters,
for moving hunter and dog food, water and
equipment, dramatically increased hunter morale
and efficiency.
In the last nine months of the Santiago campaign,
ground hunters were ferried daily to or from
work sites. The helicopter’s GPS tracks show
where hunters were camped and where they
were deployed or picked up. Moving hunters by
helicopter allowed them to nearly double the
number of kilometers invested in hunting instead
of spending time traveling on trails to and from
work sites. Hunters typically logged 80 km of
GPS track in a 10 day period. Distance covered
was limited by weather. In summer dogs could
not work past 10AM as scent would burn off the
ground and also dogs would overheat. As
helicopter support was limited to daylight hours,
hunters were limited in the number of effective
hours they could work per day.
FACT BOX
Ground work:
• 9 months of systematic
island monitoring
• 12 trips
• 10,121 km walked
Aerial work:
• 7 months of logistic support (LS)
• Nearly 220 hours flown in LS
• Nearly 19,000 km flown in LS
Feral FREE!
Santiago: last goats & last Judas
Confirming eradication
The last four goats were shot on Santiago by ground hunters working in rastrillo hunting system. They were found in dense
vegetation on the southern slope of the island on November 25th 2005. All were adult females, and none was pregnant. The
last adult feral male had been removed four months earlier. Throughout the last year of the campaign we estimated the age of
kids and measured fetuses in any pregnant females shot, to determine when they had conceived. As male Judas goats were
sterile, kill records of when we had removed feral males provided an indication as to whether males were still present on the
island. After the last rastrillo sweep in March 2006 with no goats or sign of goats found, we determined that the island was
free of goats. Twenty Judas goats were then deployed to be monitored annually for re-introductions. If goats are detected in
the future, DNA samples from goat populations around the archipelago will enable managers to determine from where they
were introduced or whether they were remnants that had escaped detection.
FACT BOX
Systematic monitoring period
• 23 goats eradicated in total
• 16 last goats found in highlands
JG situation
• 12 female Judas goats left on Santiago
• 8 male Judas goats left on Santiago
CONFIRMING ERADICATION
& ECOLOGICAL EXTINCTION
51

CONFIRMING ERADICATION
& ECOLOGICAL EXTINCTION
52
Isabela: last goats & last Judas
Ecological extinction
The status of Isabela
Months of monitoring Judas goats on the northern volcanoes allows us to confidently declare northern Isabela goat-free. The
last group shot on the north was at the edge of the Perry Isthmus in early December 2005. Southern Isabela’s goat population
has been reduced to extremely low levels; 20-30 individuals may remain, maybe less. The sex ratio of this remnant
population is likely highly skewed towards females as Mata Haris facilitated the detection and removal of males and there is
a good chance that this scattered population may not recover. Alternatively, to remove the remaining animals and confirm
eradication in the south would involve many hundreds of thousands of dollars. With a high re-introduction risk potential this
is a poor investment; the island is so large that annual monitoring for re-introductions is very expensive. A revised strategy
involves eradicating goats from the three other, smaller islands in the archipelago, to eliminate the potential supply of goats
and then return to Isabela to mop-up and confirm eradication.
Some 266 Judas goats have been left on Isabela. As they are sterile
there is no risk of them reproducing, and due to the high costs
involved with removing them, the decision was taken to leave them as
they may assist with mop-up and confirmation of eradication in the
south in the future.
FACT BOX
• 266 Judas goats left on Isabela
- 5 on Ecuador volcano
- 42 on Wolf volcano
- 31 on Darwin volcano
- 86 on Alcedo volcano
- 102 on Southern Isabela volcanoes
FACT BOX
Results from aerial activities
Total donkeys killed: 1235
Per Island
• Total donkeys killed Santiago: 23
• Total donkeys killed Isabela: 1212
- Total donkeys killed South Isabela: 1100
- Total donkeys killed Alcedo: 112
Per Year
• Total donkeys killed 2004: 155
• Total donkeys killed 2005: 966
• Total donkeys killed 2006: 114
Killing 2 “birds” with one stone!
Eradicating donkeys
Donkeys were first recorded on the Galapagos archipelago in 1834 on Floreana Island, introduced from the coast of
Ecuador. Oil seekers moved donkeys around the archipelago for transporting kegs of tortoise oil to ships and
settlements. By 1875 large numbers of donkeys roamed Santiago, and in the 1880s donkeys were recorded as
numerous on Isabela, San Cristobal, Floreana and Santa Cruz Islands.
As a “by-product” of the Project Isabela effort in removing goats, donkey eradication has proven to be very successful.
After decades of sporadic control programs on Santiago Island and Alcedo volcano, Isabela Island, donkey populations
were removed from both areas, concurrent with our goat eradication program. Both ground and aerial hunting
programs were utilized. The latter method was highly efficient; donkeys were removed from Santiago Island with less
than 80 hours of aerial hunting and from Alcedo with 517 hours of aerial hunting. Given the clear impacts of
introduced herbivores on islands worldwide, feral donkey populations should be routinely removed from islands.
53

BENEFITS BENEFITS
Broader considerations
So, was it worth it? 56
Rail recovery on Santiago 57
55

BENEFITS
56
So, was it worth it?
As of today (2PM Galapagos time, March 30th 2006),
we have closed down all field activities on Santiago and Isabela Islands.
The structure and facilities at Cowley camp are gone and all the other smaller camps
have been evacuated and all the personnel and dogs are safely back home. The helicopter
is in the process of being packed in a container to go home too! All the objectives and
challenges planned many years ago have been fulfilled and proudly we can report that
we have gone beyond what was planned and expected! Therefore, I would like to say that
we have done what the World believed was impossible! Pigs, goats and donkeys are part
of Santiago´s history as well as from the whole of northern Isabela!! THANK YOU ALL.
Why did we need to do this?
(Felipe Cruz´s message to Project Isabela´s Team on Final Day)
These hungry mouths had been putting severe and unnatural pressure on the native vegetation, reducing lush forested
ecosystems to dry and degraded grasslands. This had severe consequences on food and water availability for the giant
tortoises and land iguanas, and nesting habitat for the native birds. In addition, several endemic plant species were reduced
to only a handful of individuals in rocky areas out of reach of the herbivores.
What has the eradication achieved?
We will need to be patient for full vegetation recovery on the islands, but we have every reason to be optimistic that the
eradications of goats and donkeys will have a dramatic effect. Before we even thought it might be possible to carry out
eradications, several areas of native vegetation were fenced. Within five to ten years it became obvious that the native forest
was recovering within the fenced areas and that these areas were being favored by native birds, insects and land snails.
Several of the rarest plant species were also fenced, which helped their survival.
Following the eradications, we can already see a similar process beginning throughout the islands. Seedlings are coming up
in the grasslands created by goats in the highlands of Santiago. In time these seedlings will once again produce the extensive
forests that the goats destroyed. Our regular monitoring of the rarest plant species will undoubtedly tell us of similar success
stories for these species too.
We are also seeing some exciting effects amongst the animals, Galapagos rails, thought to be heading towards extinction in
1986 on Santiago, are today very common in the highlands. In time we also hope to see an increase on Isabela of the
archipelago’s largest population of giant tortoises and land iguanas.
Was it worth all those $ millions?
The root cause of the ecosystem degradation on these islands was overgrazing by mammalian herbivores. Until they were
eradicated we had been trying to avoid complete disaster by addressing the symptoms, rather than the cause.
Project Isabela provided us with a one-off investment of $93.79/ha on Santiago and $6.56/ha on Isabela and has set
hundreds of species free from the effects of overgrazing. We will not need to invest in expensive single-species recovery
programs or small-scale and unsustainable restoration plots anymore. Instead, we only need to monitor and help direct the
dynamic ecological processes of ecosystem recovery as the islands return to normal.
Ecosystems are more than a sum of their parts – the individual components are dependent upon each other, for food, shelter,
reproduction, pollination and seed dispersal. These interactions are an important driving force behind the evolutionary
processes that have made the Galapagos famous. With the completion of the eradications, the natural ecological and
evolutionary processes can resume.
So, was it worth it? YES
See amazing vegetation recovery examples of Santiago (p.24) and Alcedo volcano on Isabela (p.34) in this document.
Rail recovery on Santiago
Charles Darwin visited the highlands of Santiago in 1835 and noted in his diary that a small water rail
could be found in very high numbers. Goats and donkeys devastated their highland habitat and pigs
preyed directly on rails and their eggs. By the mid 1980s it was estimated that less than 100 individuals
remained on the island and that the population would be extinct within several years if pigs, goats and
donkeys remained. Those threats have been removed and the Galapagos rail has dramatically increased
in numbers. Current densities appear comparable to Darwin’s description. Many other species have also
benefited from restoration efforts.
(Rosenberg, D.K. (1990) The impact of introduced herbivores on the Galapagos rail (Laterallus spilonotus). Monographs in
Systematic Botany from Missouri Botanical Gardens, 32, 169-178.)
BENEFITS
57

58
PUBLICATIONS
BY PROJECT ISABELA
Campbell, K. (2000). Update - Ecuador: Galapagos Judas goats. Aliens 10, 18.
Campbell, K. J. (2002a). Advances in Judas goat methodology in the Galapagos Islands: manipulating the animals. In ‘Judas
Workshop 2002.’ (Eds. Gregory, J., Kyle, B., Simmons, M.). pp. 70-77. (New Zealand Department of Conservation, Otago
Conservancy: Dunedin, New Zealand.)
Campbell, K. J. (2002b). Annotated bibliography of Judas goat and related literature. In ‘Judas Workshop 2002.’ (Eds. Gregory,
J., Kyle, B., Simmons, M.). pp. 125-128. (New Zealand Department of Conservation, Otago Conservancy: Dunedin.)
Campbell, K. J. (2007). Manipulation of the reproductive system of feral goats (Capra hircus) to increase the efficacy of Judas
goats: field methods utilising tubal sterilisation, abortion, hormone implants and epididymectomy. PhD Thesis,
University of Queensland, Gatton.
Campbell, K. J., Baxter, G. S., Murray, P. J., Coblentz, B. E., Donlan, C. J. (2007). Development of a prolonged estrus effect
for use in Judas goats. Applied Animal Behaviour Science 102, 12-23.
Campbell, K. J., Baxter, G. S., Murray, P. J., Coblentz, B. E., Donlan, C. J., Carrion G., V. (2005). Increasing the efficacy of Judas
goats by sterilisation and pregnancy termination. Wildlife Research 32, 737-743.
Campbell, K. J., Donlan, C. J. (2005). Feral goat eradications on islands. Conservation Biology 19, 1362-1374.
Campbell, K. J., Donlan, C. J., Cruz, F., Carrion, V. (2004). Eradication of feral goats (Capra hircus) from Pinta Island,
Galapagos, Ecuador. Oryx 38, 1-6.
Carrion, V., Donlan, C. J., Campbell, K., Lavoie, C., Cruz, F. (2007). Feral donkey (Equus asinus) eradications in the Galapagos.
Biodiversity and Conservation 16, 437-445.
Cruz, F., Donlan, C. J., Campbell, K., Carrion, V. (2005). Conservation action in the Galapagos: Feral pig (Sus scrofa)
eradication from Santiago Island. Biological Conservation 121, 473-478.
Donlan, C. J., Tershy, B. R., Campbell, K. J., Cruz, F. (2003). Research for requiems: the need for more collaborative action
in eradication of invasive species. Conservation Biology 17, 1-2.
Donlan, C. J., Campbell, K., Cabrera, W., Lavoie, C., Carrion G., V., Cruz, F. (in review). Recovery of the Galapagos Rail
(Laterallus spilonotus) following the removal of invasive mammals. Conservation Biology.
Donlan, C. J., Campbell, K., Carrion G., V., Lavoie, C., Cruz, F. (2005). Project Isabela: Update on introduced herbivore
eradications in the Galapagos Islands. Aliens (IUCN SSC Invasive Species Specialist Group) Newsletter 21, 8.
Lavoie, C., C. J. Donlan, K. Campbell, F. Cruz, V. Carrion. 2007. Geographic tools for eradication programs of insular nonnative
mammals. Biological Invasions. 9: 139-148.
Project Isabela. (1997). ‘Plan for the protection of northern Isabela Island, Galapagos National Park, Ecuador, from ecosystem
damage caused by feral ungulates.’ Charles Darwin Research Station/Galapagos National Park Service.
Project Isabela. (2001). ‘Hunting dog training manual.’ Charles Darwin Foundation / Galapagos National Park Service.
THE PROJECT ISABELA TEAM

ISBN-10: ISBN-9978
ISBN-13: ISBN-978-9978-53-027-6
Author registration number: 026102
Acronyms
©2007, Charles Darwin Foundation (CDF) / Galapagos National Park Service (GNPS).
Total or partial reproduction of the document is permitted if referenced.
PI : Project Isabela
GEF : Global Environmental Facility
GNP : Galapagos National Park
GNPS : Galapagos National Park Service
CDF : Charles Darwin Foundation
GIS : Geographical Information System
GPS : Global Positioning System
JG : Judas Goat
Lavoie, C., Cruz, F., Carrion, G. V., Campbell, K., Donlan, C. J., Harcourt, S., Moya, M. (2007). The Thematic Atlas of Project
Isabela: An illustrative document describing, step-by-step, the biggest successful goat eradication project on the Galapagos
Islands, 1998-2006. Puerto Ayora, Galapagos: Charles Darwin Foundation. 60 pp.
This document is printed on Fox River Sundance Felt Ultra White, 50% recycled, 30% post consumer.

The work reported here was realized with the support of the Project ECU/00/G31
“Control of Invasive Species in the Galapagos Archipelago”, a donation from the Global Environment Facility (GEF)
to the Ecuadorian Government, represented by the Ministry of Environment.
Project ECU/00/G31 is implemented by the United Nations Development Program (UNDP)
and is executed by the GNPS, CDF, National Institute for Galapagos (INGALA) and Ecuadorian Service for Agriculture
and Livestock Sanitation – Galapagos (SESAGalápagos).
The opinions expressed in the document are the sole responsibility of the authors
and do not necessarily reflect GEF / UNDP´s opinion.