They killed 140,000 goats, and they said it was for ecological protection?

The gunmen on the two helicopters, armed with shotguns and semi-automatic rifles, began to clean up the ground. Areas with dense vegetation were not conducive to air combat, so the "ground guerrillas" equipped with hunting dogs and satellite positioning systems defeated them one by one...

Such a large-scale and professionally equipped operation had one goal: to kill goats.

Goats on Isabela Island | Galapagos Conservacy

This is Project Isabella, an ecological restoration project taking place in the Galapagos Islands. The main goal of this project is to eliminate all goats from the entire Galapagos Islands. But what did the goats do wrong?

Goat Removal Program

This was not a "random" killing plan.

The Galapagos Islands are located in the eastern Pacific Ocean, and Isabela Island is the largest of all the islands. The isolation of the ocean has given the Galapagos Islands a unique natural environment, which has evolved many unique species. When Darwin passed here on the Beagle, he was shocked by the biodiversity on the islands and rethought the origin of species. More than 100 years later, the Galapagos Islands were listed as the first World Heritage Site by UNESCO.

Galapagos sea lion (Zalophus wollebaeki), the smallest sea lion, on San Cristóbal Island | Diego Delso / Wikimedia Commons

The "killing plan" was also approved by the United Nations Development Programme and the United Nations Environment Programme.

In 1999, Project Isabela was launched to test the feasibility of goat eradication on Pinta Island, and later on Santiago and Isabela Islands.

The removal plan usually starts with hunting on the ground, followed by the aerial hunting phase described at the beginning of the article. However, during this long battle royale, the surviving goats became more and more alert and began to hide in caves and rugged magma cracks to escape pursuit. At this time, flying around in helicopters or using a large number of manpower to find those hidden goats was too "cost-effective". People thought of a more efficient method - releasing "Judas goats".

A Judas sheep wearing a radio collar. Judas sheep are a common method of removing goats in low-density populations, but the sound of gunfire and repeated "being left alone" may affect their mental health | pestsmart.org.au

Goats are gregarious animals. When they are separated from the group, they will actively look for companions. The "Judas sheep" method takes advantage of this characteristic of goats. The staff first selects a few "traitors", puts radio collars on them, and then releases them on the island. People only need to find the "Judas sheep" through the collars, and then they can follow the clues to find other sheep hiding in the corners. The "Judas sheep" who know nothing will be released back to the island, and continue to repeat the process of "being forced to betray their companions."

But that's not enough. A perfect "Judas sheep" should not only actively look for companions, but also automatically attract companions to its side. So scientists came up with a new method. In the Isabella Project, researchers sterilized some female goats and forced them to be in estrus for a long time by implanting hormones to lure hiding male goats. This special female individual is called "Mata Hari" goats, a name taken from the famous double-agent female spy during World War I.

Mata Hari, 1906｜Léopold-Émile Reutlinger

Ecological killer brought to the island

In 2006, the Isabela Project was basically completed. More than 140,000 wild goats were eliminated at a cost of more than 10 million US dollars. Pinta Island, Santiago Island and the northern part of Isabela Island were successively declared to be free of goats, with only some "Judas sheep" left on the islands for continued monitoring. In addition to goats, pigs and donkeys were also eliminated in this project - these animals are invasive animals to the Galapagos Islands.

Island ecosystems are unique but often more fragile, and invasive mammals are the main culprits for their collapse, with goats being one of the most destructive invaders.

Goats are very resilient | Josh Donlan

Goats are very non-picky herbivores. They not only eat leaves and a variety of herbs on trees, but also eat capsules that fall on the ground and even eat tree bark. Even when leaves contain substances that are unpalatable to other herbivores, goats can still enjoy them. By climbing and trampling, they also inhibit the regeneration of trees and grasslands.

Not only that, goats also have a high reproductive potential. Female goats reach sexual maturity at 6 months old, and without external control, the population can increase by 75% each year.

There were no goats in the Galapagos Islands originally. Whalers and pirates brought goats to the islands from the 17th to the 19th century. They had plenty of food and no natural enemies, so they reproduced quickly. By the 1990s, there were already 250,000 goats on the Galapagos Islands.

Goats rapidly multiplied after being brought to the Galapagos Islands | Huffington Post

The explosive growth of goat populations has completely destroyed forests and grasslands wherever they go, causing large-scale ecological degradation. Many endemic species on the Galapagos Islands are in danger. Life that has evolved in an isolated environment for tens of thousands of years is vulnerable to invasive species.

The Galapagos tortoise

The survival of the Galapagos tortoise is also at risk due to the invasion of goats.

The Galapagos tortoise is a unique and iconic animal of the Galapagos Islands. It belongs to the genus Tortoise and is the largest of the tortoises, weighing up to 400 kg. The average lifespan of wild individuals is over 100 years. In order to adapt to the environmental differences of different islands, the Galapagos tortoise has evolved into as many as 15 species, but 2 of them are extinct, and all the remaining species are still on the ICUN Red List of Endangered Species.

Lonesome George is a Pinta Island Galapagos tortoise (Geochelone nigra abingdoni) | Mike Weston / flickr

"Lonesome George" is probably the most famous tortoise. He is the last Pinta Island Galapagos tortoise in the world. Coincidentally, Pinta Island is the island where the goat removal program was first piloted. In 1971, zoologists discovered George on Pinta Island, at which time the vegetation on the island had been almost completely destroyed by goats. After the Isabela Project, the ecology on Pinta Island gradually recovered; but George, who was transferred to the research station for breeding, never left any offspring. In 2012, George died, and the Pinta Island tortoise species was declared extinct.

The impact of the goat disaster is most evident in the forest area south of the Alcedo Volcano on Isabela Island. When the dry season comes, thick, wet fog blows up along the outer edge of the volcano, settles on the epiphytes on the trees, and liquefies into water, which drips to the ground and forms shallow pools under the shade of the trees. The tortoises can only survive by gathering in this precious oasis under the shade. However, when the goats eat the epiphytes, the pools are difficult to form, and the tortoises no longer have a precious water source in the dry season.

A herd of goats gather around a giant tortoise in the Galapagos Islands in 2004. | Mark Moffett / Minden Pictures / Corbis

Before humans arrived in the Galapagos Islands, the population of giant tortoises reached 200,000 to 300,000, 10 times the current number. They were considered by whalers and sailors from the 17th to 19th centuries as an excellent source of fresh meat for long-distance voyages, and were also used to refine oil - although humans have long stopped doing so, as long as invasive species such as sheep, pigs, and donkeys are still there, the Galapagos giant tortoises will only go extinct day by day.

A protracted war

There had been goat culls in the Galapagos before Project Isabela, with the first recorded systematic culling taking place in 1971; over 30 years, goats were culled on 13 islands, with a total of about 200,000 goats killed, including Project Isabela.

However, removal does not mean the end: some local fishermen, dissatisfied with fishing restrictions in nearby waters, used goats as a "weapon" to threaten the government and the Galapagos National Park. At least nine deliberate reintroductions have been recorded, and according to 2009 data, it cost about $270,000 to remove these new populations again.

Local fishermen hold up signs during a protest in 2004, threatening to introduce goats to Fernandina Island (the only large island in the archipelago without a history of herbivore invasions) | References [1]

The restoration of the ecosystem is an extremely complex and difficult process, and the removal of invasive species is only the beginning. In order to restore the population of native species in the future, long-term and continuous conservation work is needed; in order to prevent the explosive growth of the tourism industry from bringing more invasive species and environmental damage, relevant policies need to be introduced; as the population of native residents in the Galapagos Islands increases, the pressure on local natural resources also increases. How to find a balance between ecological protection and economic development is a difficult problem facing environmental protection around the world.

In today's world where species are becoming extinct at an accelerated rate, we sometimes have to focus on which species still have hope of being saved. Fortunately, in 2021, the total population of Galapagos tortoises has recovered to about 60,000, and the native vegetation is also recovering - although it is far from the prosperity of the past, it is also an encouraging start.

Santiago Island before and after goat removal program | Marc Party & GNPD

One of the largest and most successful ecological restoration efforts in history, Project Isabella was achieved through the joint efforts of governments, local residents, biologists, social workers and educators, and was built on the bodies of hundreds of thousands of innocent invasive animals that had to be removed.

The war against invasive species continues in the Galapagos Islands. Although the cost is enormous, humans must take responsibility for our past and for future generations.

We cannot deprive future generations of their right to inherit our natural heritage.

Invasive species are one of the factors that threaten biodiversity. On the surface, the introduction of alien species seems to increase the species diversity of a region; however, once alien species adapt to the new environment and lack natural enemies, they may become "invasive species", occupying the survival resources of native species, and even eventually leading to a reduction in biodiversity and the collapse of the ecosystem.

In addition to invasive species, habitat reduction and fragmentation, overfishing, agricultural monoculture, genetic pollution, climate change and other factors also affect biodiversity. Protecting biodiversity not only retains more species, but also maintains the balance and stability of the ecosystem through the interconnectedness of these species.

As the theme of this year's "International Day for Biological Diversity" suggests, protecting biodiversity is "building a shared future for all life."

References

[1] Carrion V, Donlan CJ, Campbell KJ, Lavoie C, Cruz F (2011) Archipelago-Wide Island Restoration in the Galápagos Islands: Reducing Costs of Invasive Mammal Eradication Programs and Reinvasion Risk. PLoS ONE 6(5): e18835. https://doi.org/10.1371/journal.pone.0018835

[2]https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3092746/

[3] https://www.galapagos.org/conservation/our-work/ecosystem-restoration/project-isabela/

[4] https://www.galapagos.org/conservation/our-work/tortoise-restoration/restoring-existing-populations/

[5] https://www.worldwildlife.org/ecoregions/nt1307

[6] https://www.environment.nsw.gov.au/topics/animals-and-plants/threatened-species/nsw-threatened-species-scientific-committee/determinations/final-determinations/2004-2007/competition-and-habitat-degradation-by-feral-goats-capra-hircus-key-threatening-process-listing

[7] https://www.galapagos.org/conservation/our-work/tortoise-restoration/

[8]https://www.nationalgeographic.com/animals/reptiles/facts/galapagos-tortoise

[9] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5597199/

Author: Fufu Tea

Editor: Mai Mai

This article comes from the Species Calendar, welcome to forward

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