What is a judas goat

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Traitors in the Herd

Judas goats may not be as common today, but they used to be found in many livestock operations. Aptly named, Judas goats lead their herd mates to slaughter, escaping death themselves. They have been very useful in recent history as well. The Galapagos Islands used Judas goats to help save multiple endangered species.

Judas goats are named as a Biblical reference to Judas Iscariot betraying Jesus for twenty pieces of silver. The reward for Judas goats? They get to continue living.

In the past, Judas goats were commonly used in sheep and cattle herds. The goat, usually a wether, would be trained to lead the sheep to certain pastures for grazing. Eventually, that same herd was led back to where they would be slaughtered for meat production. Year after year, this Judas goat would lead a fresh group of sheep until their demise. Cattle herds sometimes used a Judas steer instead of a goat, but the concept is the same.

We have record of three goats being released on the small island of Pinta in 1959, and by the 1970s those three goats had reproduced into over 40,000.

In the Galapagos Islands, there live many animals not found anywhere else in the world. However, in the past few centuries, the arrival and settlement of people has shown us how delicate their ecosystem can be. Invasive species began to disrupt life cycles and use the resources needed by the indigenous wildlife. While these invasive species may not have been a problem where they came from, they usually don’t have the same predators to keep populations under control if they are introduced elsewhere. This was the story of the goats on the islands.

Goats had been brought and released to be hunted as a source of food when the need arose. We have record of three goats being released on the small island of Pinta in 1959, and by the 1970s those three goats had reproduced into over 40,000. Goats were released on the various islands throughout the 19th and 20th centuries. Because goats had no natural predators on the Galapagos Islands and can reproduce rapidly, the population quickly grew out of control.

When faced with overpopulation, the goats in the islands essentially ate everything in sight. This caused erosion in some places and lack of natural food sources for many of the local wildlife, especially the tortoises. In the late 1900s, the population of giant tortoises was tanking, and quick action needed to be taken. In came Project Isabela.

Project Isabela was a plan to eradicate the invasive feral goats (plus the pigs and donkeys on Santiago Island) from the Galapagos Islands. At first, herds of goats were simply rounded up and humanely killed. However, the more goats that were killed, the harder it became to find the rest. Next was hunting by helicopter done by professional marksmen. In the same pattern, goats became harder and harder to find, and so the next step of Project Isabela was to bring in Judas goats.

The Judas goats used in the Galapagos Islands were fitted with radio collars and released onto the islands. Being herd animals, the lone Judas goats quickly sought out their own kind. The marksmen would then fly in by helicopter and eliminate the herd of feral goats, leaving only the Judas goat to find another herd. Near the end of Project Isabela, the female Judas goats were sterilized and put in a chemically induced heat to attract the few remaining male goats on the island. These were called Mata Hari goats.

Those behind the project to eradicate over 200,000 goats were not numb to the deaths. It was difficult to see all the goat bodies, but preserving the rare species found on the Galapagos Islands was more important. There were simply too many goats to relocate, and the cost to attempt a relocation would have dwarfed the 6 million spent to kill them. The bodies of the goats were left on the land to replenish the soil as they decomposed. The goats had taken so much from the islands that nutrients were severely depleted. It was natural that their death not only stopped the destruction but began the reversal of the damage.

While that price was necessary to preserve the islands (goats can be found elsewhere, many Galapagos species cannot), that price could have been avoided long ago by not introducing them.

This is not the only instance of goat eradication on islands where they are invasive. San Clemente Island goats are critically endangered because of their eradication. Hawaii has also brought in a feral goat hunting season on the island of Kauai.

It is hard to learn of so much death of an animal that we love. The goats did not choose to be brought to islands that could not support them, and yet they paid the price. While that price was necessary to preserve the islands (goats can be found elsewhere, many Galapagos species cannot), that price could have been avoided long ago by not introducing them. Of course, centuries ago, we did not understand the threat of invasive species. The main concern was a guaranteed food source of which they were familiar.

This brings up a topic that is pertinent today. Domestic goats should never be released to the wild. Who would do that, right? If your goats can escape their enclosures, they can enter country where they are neither safe nor welcome. Wildlife conservancy agencies absolutely do not want any contact between your domestic livestock and wild animals. Disease transfer is the top concern because the wild populations may be more susceptible to regular diseases of your goats. It is not just goat-to-goat either. The Big Horn Sheep Foundation greatly fears the transfer of m. ovi from goats to big horn sheep. Deer are closely related to goats and thus diseases can transfer between them as well (yes, to your goats as well as from). If you backpack with your goats, do not allow them to socialize with wild animals.

While the idea of Judas goats leading their herds to certain death can be tough to swallow, wash it down with the knowledge that at least in the Galapagos Islands, it was done to save other species. You can help prevent the need of future Judas goats by keeping your goats safe and enclosed. Transport them wisely and know how to secure them if you are backpacking with goats. The prevention of mass death is on all of us.

References

Cruz, F., Carrion, V., Campbell, K. J., Lavoie, C., & Donlan, C. J. (2010). Bio-Economics of Large-Scale Eradication of Feral Goats From Santiago Island, Galápagos. The Journal of Wildlife Management, 191-200.

Galapagos Conservancy. (n.d.). Project Isabela. Retrieved from Galapagos Conservancy: https://www.galapagos.org/conservation/our-work/ecosystem-restoration/project-isabela/

Originally published in the January/February 2022 issue of Goat Journal and regularly vetted for accuracy.

A goat trained to lead other goats to a place of slaughter.

A goat trained to find feral goats.