Llamas Once Roamed North America. Could They Help Restore It Again?
Llamas helped rebuild soil and vegetation below a retreating glacier in Peru. Their deeper history makes the experiment even more interesting.
Most Americans think of llamas as South American animals.
They are. But that is only the recent part of their story.
Camelids evolved in North America. Their ancestors lived here for tens of millions of years before some crossed into Eurasia and others moved south when the Isthmus of Panama connected North and South America. The South American branch eventually produced llamas, alpacas, guanacos and vicuñas.
That history makes a recent experiment in the Peruvian Andes especially interesting.
Researchers working with local farmers placed llamas on newly exposed ground below the retreating Uruashraju glacier in Peru's Cordillera Blanca. The terrain was harsh: thin soils, sparse vegetation, low fertility and land that had been covered by ice only decades earlier.
Beginning in 2019, researchers established four llama plots and four control plots. Three llamas grazed each treatment plot for only three days each month. The experiment continued through 2022.
The result was measurable.
After three years, soils in the llama plots contained more organic carbon and nitrogen. The animals were also moving seeds into the area through their dung and potentially their coats and hooves.
Then the vegetation responded.
Between 2021 and 2022, average vascular plant cover in the llama plots increased 57 percent, from about 9 percent to nearly 14 percent. Researchers also documented four plant species in those plots that had not been present when the experiment began.
This was not simply a fertilizer experiment.
The animals were grazing. They were trampling. They were depositing manure. They were moving seeds. They were changing competition among plants and redistributing nutrients across the landscape.
In other words, the llamas were functioning as part of the ecosystem.
That distinction matters.
Land management often treats grazing as a disturbance that must be reduced or eliminated. But grazing animals can also perform ecological work. They remove vegetation, return nutrients to soil, transport seeds, disturb soil surfaces and create opportunities for different plants to establish.
Whether that influence is beneficial depends on the animal, the density, the timing, the landscape and the condition of the land.
The Peru study does not prove that llamas—or any other grazing animal—improve every landscape. The researchers themselves emphasize that longer-term study is needed.
What it does show is more interesting:
Even relatively modest animal impact can rapidly change ecological processes on extremely young and difficult ground.
The experiment also raises a larger question about how we think about "native" animals.
Llamas are commonly regarded in North America as exotic livestock. Yet camelids originated here. North America was the center of camel evolution before their descendants dispersed into Asia and South America.
That does not automatically make modern llamas appropriate everywhere their distant ancestors once lived.
But it should make us cautious about treating today's distribution of animals as if it were an ecological starting point.
Landscapes change. Species disappear. Others move. Humans accelerate some of those changes and attempt to reverse others.
The useful question is not simply:
Was this animal here recently?
It is also:
What ecological function does the animal perform, and what happens to the land when that function is restored?
At Pitchstone Waters, we have long argued that land, water, plants, wildlife and grazing animals should be considered together.
Healthy ecosystems were not created by protecting plants from animals. They evolved with animals—grazing, browsing, trampling, fertilizing, hunting, dying and moving across landscapes.
The Peruvian llama experiment offers a small but unusually clear demonstration of that principle.
Put animals back onto barren ground.
Measure what happens.
The soil changes.
Seeds move.
Plants respond.
And a landscape that appeared almost lifeless begins behaving like an ecosystem again.
That is worth studying far beyond the Andes.
Source
Anaïs Zimmer et al., Llamas (Llama glama) enhance proglacial ecosystem development in Cordillera Blanca, Peru, Scientific Reports 13, 15936 (2023).
Editorial note: This is a Pitchstone Waters institutional editorial developed with AI assistance under human direction. It draws on Chris Gill’s published work and Pitchstone’s documented principles, but it is not presented as a new article written by Chris.
