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Biodiversity Conservation in the Galápagos Islands, Ecuador:

Experiences, Lessons Learned, and Policy Implications

C. Josh Donlan, Victor Carrion, Karl J. Campbell, Christian Lavoie and Felipe Cruz

ABSTRACT Invasive alien mammals are the major driver of biodiversity loss and ecosystem degradation on

islands. Over the past three decades, invasive mammal eradication from islands has become one

of society’s most powerful tools for preventing extinctions of insular endemics and restoring

insular ecosystems. A number of innovative programs have recently taken place in the Americas

that have focused on restoring and protecting islands. Project Isabela in the Galapagos Islands is

the world’s largest island restoration program to date. It was the largest component of a holistic

approach to invasive alien species management in the Galápagos Islands. Project Isabela removed

>140,000 goats from Pinta, Santiago, and northern Isabela Islands (>500,000 ha) for a cost of

US$10.5 million. Leveraging the capacity built during Project Isabela, and given that goat

reintroductions have been common over the past decade, an archipelago-wide goat eradication

strategy was implemented. Feral goats remain on three islands in the archipelago, and removal

efforts are underway. Efforts on the Galápagos Islands demonstrate that for some species, island

size is no longer the limiting factor with respect to eradication. Rather, bureaucratic processes,

financing, political will, and stakeholder approval appear to be the new challenges. Eradication

efforts have delivered a suite of biodiversity benefits that are in the process of revealing

themselves. The costs of rectifying intentional reintroductions are high in terms of financial and

human resources. Reducing the archipelago-wide goat density to low levels is a technical

approach to reducing reintroduction risk in the short-term, and is being complemented with a

longer-term social approach focused on education and governance.

1. INTRODUCTION

Islands make up a small percentage of the Earth’s total area, yet they harbor a large percentage of

biodiversity including many threatened and endangered species (Donlan 2008). Invasive alien

mammals are overwhelmingly the major driver of biodiversity loss and ecosystem degradation on

islands. Invasive mammals exist on over 80 percent of the world’s island groups, and

consequently nearly half of the threatened mammal and bird species on the International Union

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for the Conservation of Nature’s Red List are island species (Atkinson 1985; Aguirre-Muñoz et

al. 2008). Non-native predators, such as rats (Rattus spp.) and cats (Felis silvestris catus), have

decimated endemic vertebrate populations and extirpated seabird colonies on islands around the

globe (Towns et al. 2006; Jones et al. 2008; Bonnaud et al. 2011). Non-native herbivores such as

goats (Capra hircus) have caused wholesale changes to insular plant communities, as well as

secondary impacts via habitat degradation (Campbell & Donlan 2005; Donlan et al. 2007). As

omnivores, feral pigs (Sus scrofa) are responsible for wholesale adverse effects on islands,

threatening native biodiversity and changing ecosystem dynamics (Cruz & Cruz 1987; Roemer et

al. 2002). Over the past three decades, however, invasive mammal eradication from islands has

become one of society’s most powerful tools for preventing extinction of insular endemics and

restoring insular ecosystems (Veitch & Clout 2002; Donlan & Wilcox 2008).

Starting in the 1970s, conservation practitioners in New Zealand and Australia were the

first to develop methodologies to restore island ecosystems by removing invasive mammals

(Towns & Broome 2003; Campbell & Donlan 2005; Howald et al. 2007). Those techniques have

drastically improved over the past four decades, and island restoration programs are now present

around the globe (Veitch et al. 2011). Currently, there have been over 780 successful invasive

alien vertebrate eradications from islands (Keitt et al. 2011). Invasive mammals are now being

removed from larger islands at a faster rate than ever before (Howald et al. 2007). Over the past

decade, a number of innovative programs have taken place in the Americas that have focused on

restoring and protecting islands (Ebbert & Byrd 2002; Tershy et al. 2002; Morrison et al. 2007;

Aguirre-Muñoz et al. 2008; Howald et al. 2010). Here, we reflect on a program in the Galápagos

Islands—Project Isabela—to explore lessons learned and policy implications for biodiversity

conservation on islands across the American continent. Project Isabela, which spanned over a

decade, is the world’s largest island restoration effort to date.

2. BACKGROUND

Biologists Alfred Russell Wallace and Charles Darwin both witnessed the destruction of St.

Helena Island in the Atlantic Ocean by goats in the 19th century. Introduced there in the 1200s,

goats are responsible for at least eleven plant extinctions; the real number is unknown since the

first botanical survey occurred 300 years after goats arrived. Unfortunately, goats also beat

Darwin to the Galápagos. They were eventually introduced onto thirteen islands causing

widespread habitat destruction in every case. While goats still roam the transformed landscape of

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St. Helena, many Galápagos islands are now recovering from non-native herbivory, and the entire

archipelago is on its way to becoming goat-free.

Feral goat management in the Galápagos Islands began over fifty years ago. Early

eradication campaigns were opportunistic and involved ground hunting without specialized

techniques. In 1961, goats were removed from the small island of Plaza Sur (0.12 km2). Between

then and 2003, the Galápagos National Park (GNP) and Charles Darwin Foundation (CDF)

successfully removed goat populations from six islands in the archipelago (Campbell & Donlan

2005) (Table 1).

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Table 1 Island in the Galápagos archipelago where goats have been removed.

Island

Size

(ha)

Goats Removed

(heads)

# Reintroductions (nº ; US$ of 2009)

Investment

(US$ of 2009)

Marielas Sur 1 5 Plaza Sur 12 5 Rábida 499 14 1 (unknown)

Santa Fe 2,413 3008 1 (unknown) Baltra 2,620 64

$9,515

Pinta 5,940 41,683 1 ($110,141) $83,949* Española 6,048 3,344

Marchena 12,996 497 5 ($124,064) Floreana 17,253 1,561

$643,705

San Cristobal 55,809 7,726

$680,251 Santiago 58,465 79,579 1 ($32,393) $6,349,326 Santa Cruz 98,555 1,481

$281,740

Isabela 458,812 62,868

$4,172,035

Total 719,410 201,825 9 ($266,598) $11,958,282 * Includes eradication efforts from 1999-2003; does not include prior control efforts. Goats have been removed from over 700,000 ha for a cost of $12 million. Cost data for earlier eradications are not available. Goats have been reintroduced to islands nine times, which has cost more than $266,000 to remove those new populations. Project Isabela removed goats from Pinta, Santiago, and northern Isabela Islands, along with pigs and donkeys from Santiago and donkeys from northern Isabela. Goats remain on the three islands in bold, where removal efforts are underway.

In 1997, GNP and CDF brought together local staff and 15 international experts to discuss

invasive mammal eradication and island restoration in the Galápagos archipelago (Figure 1).

Managers were particularly concerned about the rapidly increasing goat population on northern

Isabela Island that was having significant biodiversity impacts and wholesale ecosystem changes

due to overgrazing. Workshop participants concluded that goat eradication was possible for

northern Isabela at a cost of US$8.5 million over five years (Isabela Project 1997). The southern

section of the island, separated from the northern section by a 10+ km-long lava isthmus, was

considered too complex due to a small town and agricultural zone located on the southern end and

the presence of multiple invasive herbivores and plants (Figure 1). It was concluded that southern

Isabela was best targeted for restoration as a second phase to be planned and implemented

following goat eradication on northern Isabela. Following the workshop, GNP and CDF

developed a proposal to the Global Environment Facility (GEF) to eradicate feral goats and

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donkeys (Equus asinus) from the northern part of Isabela Island. The project would consist of

three phases:

1. Garner and build the necessary funding, resources, capacity, and governance, including

pilot feral goat eradication campaigns on smaller islands;

2. Eradicate goats (and donkeys) from northern Isabela; and

3. Monitor and manage the islands for goats, either individuals missed from the eradication

campaigns or new animals released illegally.

Figure 1

a) The Galápagos archipelago

b) Isabela Island.

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Southern Isabela is separated from the northern section by a 10+ km-long lava isthmus (Perry Isthmus). A small town, Puerto Villamil, is located at the southern shore of the Island.

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In 1998, GEF approved an initial funding application for a small project to demonstrate

capacity. After multiple eradication attempts prior to this, a revised goat eradication project was

planned on Pinta Island in 1999 to trial the Judas goat method and build capacity (Figure 1). In

2001, Ecuador received full funding from GEF for the project ECU/00/G31 Control of Invasive

Species in the Galápagos Archipelago. Project Isabela was part of this wider program.

3. ORGANIZATIONAL STRUCTURE AND FUNDING

Project Isabela was one of six outputs of ECU/00/G31 Control of Invasive Species in the

Galápagos Archipelago, and the largest component of a holistic approach to invasive alien

species management in the Galápagos Islands (Figure 2). The organizational structure of Project

Isabela fit within the overall structure of the GEF-funded Control of Invasive Species in the

Galápagos Archipelago (Figure 2). A blend of local and international expertise, along with

capacity building throughout the campaign, contributed to the success of Project Isabela. Project

Isabela was a bi-institutional project, managed by GNP and CDF. A manager from each

institution co-managed all aspects of the campaign; both managers were Galápagos natives. A

non-local managed field operations, including technical strategies. A Geographic Information

System (GIS) technician was present in the field throughout much of the campaign; this

facilitated an adaptive management strategy and constant reviews of hunting efficiencies and

escape rates (Lavoie et al. 2007b). A conservation scientist led efforts to strategically collect,

assimilate, and publish key data and outcomes from Project Isabela. Two to four group leaders

managed specialized aspects of the campaign (e.g., specific hunting trips and logistics). Constant

communication and coordination between the field manager and project managers was important

for success.

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Figure 2 Organizational structure of Project Isabela.

The project was one output (Output 3) of six of a larger program, Control of Invasive Species in the Galápagos Archipelago. A Program Management Unit that was overseen by the Ministry of Environment and United Nations Development Program (UNDP) managed the larger program. Two groups provided assistance to the Project Management Unit. Project Isabela was co-directed by Galápagos National Park (GDP) and Charles Darwin Foundation (CDF). The Project Management Unit and UNDP were directly responsible for the aerial contract; however, CDF and GNP co-directors oversaw its daily management. The field manager oversaw all operations on the ground, with continuous feedback from the co-directors.

A suite of agencies, institutions, and organizations funded Project Isabela. Major funding

included GEF through the United Nations Development Program, the Ecuadorian Government

through the Ministry of Environment and GNP, and through private donations to the CDF.1

1 Private donations included Charles Darwin Foundation Inc. (now Galápagos Conservancy), European Friends of Galápagos Organizations, Stewart Foundation, Merrill Foundation and Lindblad Expeditions (Galápagos Conservation Fund).

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4. CONSERVATION ACTIONS & OUTCOMES

The overall objective of Project Isabela was to restore and protect the biodiversity present in

northern Isabela Island by removing the major threat: non-native feral goats. A secondary

objective was to build capacity within the Galápagos National Park for invasive species

management that would persist beyond Project Isabela. We summarize the outputs and outcomes

here. Details on the methodologies of the eradication campaigns are published elsewhere

(Campbell et al. 2004; Campbell et al. 2005; Cruz et al. 2005; Campbell et al. 2007; Carrion et al.

2007; Lavoie et al. 2007a; Lavoie et al. 2007b; Cruz et al. 2009; Carrion et al. 2011)

Project Isabela was charged with four main outputs:

• Remove the remnant goat population from Pinta Island, where there had been multiple

eradication attempts;

• Remove pigs from Santiago Island, where an on-going control campaign was underway;

• Remove goats and donkeys from Santiago Island; and

• Remove goats and donkeys from northern Isabela Island.

Goats were removed from Pinta Island with an extensive hunting effort in 1999 (Campbell et

al. 2004). Prior to this effort the GNP had been conducting a 30-year intermittent eradication

campaign on Pinta Island. 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 and monitoring,

removed the final goats from the island.

Concurrent with the success on Pinta Island, pigs were removed from Santiago Island

(Cruz et al. 2005). After a decade of targeted pig control efforts in important breeding areas of

tortoises and sea turtles, revised techniques were implemented with the goal of eradication.

Between 1998 and 2000, a revised poisoning campaign was implemented. For the first time in

over 150 years, Santiago Island is now free of pigs. Over 18,000 pigs were removed from the

island, which is by far the world’s largest pig eradication to date.

Following on the success of the pig eradication, the Santiago Island (58,465 ha) goat

eradication campaign was mounted as an opportunistic capacity building exercise leading up to

goat eradication on northern Isabela Island. The Santiago goat eradication campaign was an

unprecedented advance in the ability to reverse biodiversity impacts by invasive species. In less

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than 4.5 years, 79,000 goats were removed from the island, at an approximate cost of US$6.3

million2 (Cruz et al. 2009). An eradication ethic combined with a suite of techniques and

technologies made eradication possible. A field-based GIS facilitated an adaptive management

strategy, including adjustment and integration of hunting methods (Lavoie et al. 2007b).

Specialized ground hunting techniques, with dogs, removed most of the goat population. Aerial

hunting by helicopter and Judas goat techniques were also critical. Judas goats are goats captured,

fitted with radio telemetry collars, and released (Taylor & Katahira 1988). Being gregarious,

Judas goats search out and associate with other goats (Rainbolt & Coblentz 1999). Judas goats

can be monitored and any associated feral goats killed (Taylor & Katahira 1988; Rainbolt &

Coblentz 1999). Mata Hari goats, sterilized female Judas goats induced into a long-term estrus,

removed males from the remnant feral population at an elevated rate, which likely decreased the

length and cost of the eradication campaign (Campbell et al. 2005; Campbell et al. 2007; Cruz et

al. 2009). The last 1,000 goats cost US$2.1 million to remove; an additional US$496,000 was

spent on monitoring to confirm eradication. Aerial hunting proved cost-effective even in a

country where labor is inexpensive. During the pig and goat eradication campaigns, donkeys were

also eradicated from Santiago Island (Carrion et al. 2007). The Santiago Island goat eradication

was by far the world’s largest goat eradication campaign.

Building on the success of the Santiago goat eradication, efforts were focused on

removing goats from northern Isabela starting in March 2004. In contrast to Santiago Island, the

majority of hunting efforts on Isabela were conducted aerially by helicopter. During the initial

phase (April 2004-May 2005), a total of 55,657 goats were killed. While we concentrated efforts

on northern Isabela, the southern part of the island was also hunted. A helicopter accident in June

2004 halted aerial hunting operations for four months. Ground hunting with dogs was limited to

seven trips, the majority of which took place in densely vegetated areas. Throughout the entire

campaign, only 2,637 goats were killed by ground hunters (Table 2).

2 All costs are in 2009 US$.

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Table 2. The Santiago and Isabela Island goat eradication campaigns during Project Isabela (2001-2006).

Santiago Isabela

Number of goats killed (% total): aerial hunting 12,192 (15%) 55,657 (89%) Number of goats killed (% total): ground hunting 66,213 (83%) 2,637 (4%) Number of goats killed (% total): Judas goat operations 1,174 (1%) 4,524 (7%) Total number of goats killed (cost) 79,579 ($6.4mm) 62,818 ($4.1mm) Duration (months) 64 24 Average $ per hectare $110 $9 Average $ per goat $81 $65 Figures do not include Judas goat operations on southern Isabela after March 2006.

Developed and demonstrated during the Santiago Island goat eradication campaign, Mata

Hari goats were a critical component of the northern Isabela goat eradication. By January 2005,

goats across all of Isabela Island were at low densities, which precipitated a switch of methods

from aerial hunting to Judas goats. Over the next three months over 700 Judas goats were

deployed throughout all of Isabela Island, including the southern portion of the island. In contrast

to Santiago Island, Judas goat monitoring was conducted exclusively by helicopter. Judas goats

were actively monitored on Isabela Island for 465 days. Over that time period, Judas goats were

checked 5,470 times; 3,439 feral goats were shot while associated with Judas goats, while 1,085

feral goats were shot during Judas goat operations but were not associated with Judas goats.

The last feral goat on northern Isabela was removed in December 2005. Monitoring

operations for Project Isabela ended in March 2006. A total of 62,818 goats were removed from

the island over 2 years for a cost of $4.1 million. Feral goats remained in low numbers on

southern Isabela. As a future monitoring tool, 266 Judas goats were left on Isabela Island. During

Project Isabela operations, donkeys were also eradicated from northern Isabela, but still persist in

small numbers on the southern section of the Island (Carrion et al. 2007).

All outputs were delivered with respect to Project Isabela. Project Isabela nearly doubled

the total area globally where goats have been removed from islands (567,000 ha) by removing

over 140,000 goats from 500,000+ ha in less than 10 years (Campbell & Donlan 2005). Some

biodiversity benefits and outcomes from Project Isabela have already been documented, while

others continue to reveal themselves and are being monitored. Additional biodiversity benefits

were also delivered post-Project Isabela, due to the institutional capacity developed (see below).

The endangered Galápagos rail (Laterallus spilonotus) has made a spectacular recovery on

multiple islands following vegetation recovery, including on Santiago and Floreana Islands, on

the latter island rails had not been documented since the late 1980s (Rosenberg 1990; Donlan et

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al. 2007). The native plant communities on Pinta, Santiago, Isabela and Floreana Islands are

recovering (Hamann 1979, 1993). Populations of eight endemic plant species listed as ‘Critically

Endangered’ or ‘Endangered’ by the International Union for the Conservation of Nature have

increased in both number of populations and individuals, including the endangered Scalesia

atractyloides that was feared extinct (Atkinson et al. 2008). The dramatic recovery of this

endemic tree following goat eradication on Santiago Island has led to a proposal to downgrade its

endangered status (Tye 2007).

Since invasive herbivore eradication is but one step in the restoration process, however,

other conservation challenges have presented themselves post-eradications. Despite concurrent

invasive plant control during Project Isabela (Cruz et al. 2009), blackberry (Rubus niveus) has

now become more common throughout the Galápagos. Some scientists suggest this may be partly

due to the release of herbivore pressure and the constant dispersal of seeds by native birds.

Systematic control and containment efforts are now being implemented and investigations to

identify bio-control agents are planned for blackberry by the Galápagos National Park.

5. ORGANIZATIONAL COORDINATION, PERFORMANCE, AND

CHALLENGES

Project Isabela was successfully co-managed by the GNP and the CDF. Aerial hunting aspects of

the campaign were contracted to a private company from New Zealand. Thus, many of the on-

the-ground management activities were managed under collaboration with a governmental

conservation agency (GNP), non-governmental organisation (CDF), and a for-profit enterprises

(private company from New Zealand, HeliPark). This structure provided a number of advantages

in navigating the many planning and implementation challenges of the project, particularly the

dynamic socio-politics. Project Isabela survived 10 Galápagos National Park Directors, several

Ministers of the Environment, and five Ecuadorian Presidents.

The project was embedded between two institutions (GNP and CDF), which provided it

some autonomy and two potential structures for decision-making. This structure allowed for

flexibility, drawing from opportunities and benefits from each of the institutions. For example,

CDF acted as a conduit for funding, and enjoyed greater flexibility in budgetary spending than

did GNP, allowing CDF to cover project costs when the GNP could not. For example, the

eradication campaign continued without breaks despite a lack of funding within the National Park

for hunters’ salaries at the start of each financial year. The non-profit and diplomatic status of

CDF also facilitated contracting outside of Ecuador and importation of firearms and

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ammunitions. Project Isabela’s formal affiliation with GNP offered distinct advantages as well,

including direct access to the Park’s infrastructure, which facilitated efficient logistics (e.g.,

access to boats, dog kennels, etc.).

There were also project advantages achieved by contracting out the aerial component of

the eradication campaign. Most importantly, highly skilled personnel and specialised equipment

could be efficiently folded into the program, which allowed additional focus and resources to be

spent on more experimental components of the project. An aerial hunting contract also provided

some risk sharing. While Project Isabela carried the risk of eradication failure, since the private

company was paid per unit of effort (i.e., helicopter hours and a mobilisation component),

operational delays and any associated financial risks were born on the private company as

opposed to Project Isabela.

Not surprisingly, a number of challenges also emerged from the government agency—

non-profit organization—for-profit enterprise partnership of Project Isabela as well. There was

added complexity in project planning, particularly the need for coordinating annual budgets.

Project Isabela was also vulnerable to potential crisis situations within either GNP or the CDF.

During the project, a large-scale oil spill and a large wildfire overwhelmed staff capacity, and

temporarily paralysed Project Isabela.

An intergovernmental agency, United Nations Development Program (UNDP), as a

partner in Project Isabela was a unique situation that has yet to be replicated in any other

eradication campaign. They provided a project advantage because of the ability to commit to

large cash outlays from a single source. The UNDP streamlined large contracts (e.g., helicopter

contracts), and provided high-level direction and pressure to keep the project a priority for the

various Ecuadorian government agencies. The UNDP also, however, brought a level of added

bureaucracy that was more focused on process as opposed to products. As a consequence,

commitment to timelines was difficult, which resulted in the consumption of funding while the

project awaited the release of additional funding.

6. ECONOMICS OF PROJECT ISABELA

Approximately $10.6 million was invested into Project Isabela.3 The majority of those funds were

spent during goat eradication efforts on Santiago and northern Isabela. Over the past decade,

3 The cost of the Santiago pig eradication program is unavailable. However, those costs are small relative to the overall investment into Project Isabela.

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removing goats from the Galápagos Islands has become more cost-effective (Table 2, Carrion et

al. 2011). Those savings stem from a variety of factors. First, the use of helicopters and aerial

hunting is more cost-effective at removing non-native herbivores compared to ground-based

hunting methods, even in countries where labor is relatively inexpensive (Cruz et al. 2009). For

example, the largely ground-based goat eradication campaign on Santiago Island cost $110 ha-1.

While a remnant goat population is still present on southern Isabela Island, the current per hectare

cost of the aerial-based Isabela campaign is $9 ha-1 – a magnitude cheaper. Second, later

eradications in the Galápagos were subsidized in the sense of capacity built. The skill level of

practitioners was already high, infrastructure existed, the efficiency of techniques had been

honed, and the institutional bureaucracy had been navigated. All of these factors resulted in cost

savings.

7. LONG-TERM CAPACITY BUILDING

Long-term capacity building during Project Isabela was particularly important because

investments in removing non-native species from islands must be weighed against the risk of

reinvasion. If there is substantial risk of reintroduction following a successful eradication,

investment in an eradication campaign is not justified. Mitigation strategies for reintroduction risk

include biosecurity programs and education (Russell et al. 2008). From an archipelago

perspective, an effective means to reduce reintroduction risk is to eradicate the target invasive

species from the entire archipelago and thus eliminate readily available sources. This approach is

valid in the Galápagos as goats are unlikely to come from continental sources and goat breeding

doesn’t occur on farms.

Contemporary feral goat introductions and reintroductions were common on the

Galápagos archipelago. Fishermen and crewmembers on boats travelling in the Marine Reserve

commonly introduce goats to islands as a food source, and more recently as a political tool and

malicious acts against the GNP to influence fishery-permitting processes in the Galápagos Marine

Reserve. The GNP manages the Marine Reserve, as well as fishing regulations within the

Reserve. Negotiations with fishermen regarding fishing seasons and catch limits have broken

down several times in the last ten years, with fisherman often leaving the negotiations with threats

of re-introducing goats to islands. At least nine intentional goat reintroductions have been

documented in the Galápagos following successful eradication programs (Table 1). These

reintroductions complicate island restoration efforts, and present a risk to conservation

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investments in the archipelago that is both difficult and expensive to mitigate. Thus, eradication

of goats from the entire Galápagos archipelago is desirable to protect the natural capital of the

islands, as well as the massive investment in restoring the islands.

Building on the capacity developed during Project Isabela, eradication campaigns were

mounted on the three inhabited islands were feral goat populations remained: Floreana, San

Cristóbal, and Santa Cruz (Figure 1, Table 1). Aerial Judas goat monitoring also continued on

southern Isabela; 50 goats and 125 donkeys were removed for a cost $318,000. Goats, cattle, and

donkeys were eradicated from Floreana Island with the use of aerial hunting, ground hunting with

dogs, and Judas goats: 1,561 goats and 380 donkeys were removed between 2006-2009. A total of

9,207 goats and 498 donkeys were removed from San Cristóbal and Santa Cruz Islands since

2006 using aerial hunting, ground hunting with dogs, and Judas goats. Feral goats currently

remain on three islands in the archipelago: a small remnant population on southern Isabela and

San Cristóbal Islands and a larger population on Santa Cruz Island. Since 2006, $1.0 million has

been spent on removing the remaining goats and donkeys on these islands. Judas goat monitoring

is continuing on Floreana, Santa Cruz, and San Cristóbal Islands.

In situations where there will be multiple programs under the same political unit and

institutions (i.e., GNP), explicitly building long-term capacity within a large project, such as

Project Isabela, is strategic. Capitalizing on that built capacity, GNP is now in the final stages of

removing feral goats from the entire archipelago. Helicopter contracts for aerial hunting are now

part of the Park’s annual budget, along with Judas goat operations. Due to the successes of

Project Isabela, the GNP now has access to the capacity, financing, and political capital to engage

in additional biodiversity conservation programs, including the removal of invasive rats from

islands and protecting their previous investments in goat eradication. While costs are not

available for earlier goat eradication campaigns, at least $12 million has been invested in

removing goats from islands in the Galápagos (Table 1).

8. CONCLUSIONS

Project Isabela demonstrated that for invasive mammalian herbivores, island size is no

longer the limiting factor with respect to eradication. Rather, costs, financing, and stakeholder

approval appear to be the new challenges. Massive investments in political and financial capital

for island restoration must be protected, including minimizing the potential for reintroductions

following eradication. Following the capacity developed during Project Isabela, GNP has

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implemented an archipelago-wide goat eradication approach that has been successful in removing

any readily available sources of goats for potential reintroduction by either eradication or

reducing remaining populations to low densities. The three remaining goat populations on Santa

Cruz, San Cristobal, and southern Isabela Islands are currently in the process of being removed.

The lessons learned from Project Isabela will prove useful as island restoration programs are

initiated in Chile, Argentina, Brazil, and elsewhere in the Americas. For example, a program is

underway to remove non-native beavers from Tierra del Fuego and surrounding islands, a

ambitious project of unprecedented size and scale (Parkes et al. 2008; Menvielle et al. 2010).

Many technical and political lessons learned from Project Isabela will be relevant to the removal

of beavers from Tierra del Fuego.

Feral goats were already present in the Galápagos when Charles Darwin arrived in 1835.

One hundred and seventy-six years later, the archipelago is quickly on its way to becoming goat-

free. At a cost that will likely be less than $20 per hectare, invasive mammal eradication from

islands is not only one of society’s most powerful tools for preventing extinction and restoring

ecosystems—but also one of the most cost-effective.

Acknowledgements

We express our gratitude to all the Galápagos National Park Service (GNPS) hunters and

helicopter pilots and crews who made this conservation action possible. We thank E. Cruz and R.

Bensted-Smith, Directors of GNPS and Charles Darwin Foundation (CDF) for putting together

the bi-institutional initiative Project Isabela (PI), and the directors after them for their continued

support. L. Cayot managed PI between 1997-8 and coordinated the 1997 international workshop

Feral Goat Eradication Program for Isla Isabela. The participants of the 1997 workshop

contributed greatly to the Plan for the protection of northern Isabela Island, Galápagos National

Park, Ecuador, from ecosystem damage caused by feral ungulates. M. Patry managed PI between

1998-2002. Additional technical support was provided by B. Coblentz, G. Halverson, C.

Harrison, R. Henderson, N. MacDonald, J. Parkes, H. Snell, R. Suber, University of New Mexico

and G. Woodhouse. Volunteers G. Banda, C. Hanson, T. Koester, R. Speed, M. Wedin, and C.

Zonfrillo contributed toward many facets of the campaign. Funding was provided by GNPS,

CDF, Charles Darwin Foundation Inc. (now Galápagos Conservancy), European Friends of

Galápagos Organizations, Galápagos Conservation Trust, Stewart Foundation, Merrill Foundation

and Lindblad Expeditions (Galápagos Conservation Fund) in collaboration with Project

ECU/00/G31 “Control of Invasive Species in the Galápagos Archipelago”, a donation from the

Global Environment Facility (GEF) to the Ecuadorian Government, represented by the Ministry

17

of Environment. The Project is implemented by the United Nations Development Program

(UNDP) and is executed by the GNPS, CDF, National Institute for Galápagos and Ecuadorian

Service for Agriculture and Livestock Sanitation – Galápagos. We thank TAME airline, Cornell

University, and Island Conservation for providing additional support. The opinions expressed

herein belong to the authors and do not necessarily reflect the opinions of GEF/UNDP.

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