Vicuñas are related to llamas and alpacas and are found high in the Peruvian Andes. (Wirestock Creators/Shutterstock)
In a nutshell
- Wild vicuñas in the Peruvian Andes create communal bathroom spots (latrines) that transform barren, post-glacier landscapes into nutrient-rich patches where new life can thrive – cutting the typical recovery time by over a century
- These latrine areas contain 62% organic matter (compared to 1.5% in surrounding areas) and maintain more stable temperatures, creating protected micro-environments that attract diverse wildlife – from microscopic organisms to large predators like pumas
- While this natural process helps some species adapt to glacier loss, it can’t keep pace with current climate change – glaciers are losing about 267 billion tons of ice annually, threatening water supplies for nearly a quarter of the world’s population
BOULDER, Colo. — High in the Peruvian Andes, where glaciers are retreating at an unprecedented rate, nature has devised an unexpected solution involving vicuñas and their bathroom habits. These wild relatives of llamas are inadvertently helping to jumpstart new ecosystems in barren, recently deglaciated landscapes—and they’re doing it one dung pile at a time.
Recent research published in Scientific Reports reveals that these cousins of llamas and alpacas are doing something remarkable in Peru’s Cordillera Vilcanota mountain range. When glaciers retreat, they typically leave behind what scientists describe as “a sea of rocks and gravel” where even the toughest plants struggle to survive. Under normal circumstances, these areas can remain plant-free for over a century. But vicuñas are changing this timeline dramatically through their distinctive bathroom habits.
“It’s interesting to see how a social behavior of these animals can transfer nutrients to a new ecosystem that is very nutrient poor,” says co-author Cliff Bueno de Mesquita, a research scientist at CU Boulder, in a statement.
Much like humans, these animals use designated spots as communal bathrooms, creating areas scientists call “latrines.” Over the past decade, researchers began noticing something intriguing. Patches of plants began emerging specifically from these vicuña dung piles in otherwise barren terrain.
Researchers studied these latrine sites at elevations up to 18,000 feet above sea level in the Peruvian Andes. They compared soil samples and various biological markers between latrine sites and nearby untouched areas to understand just how much impact these camelids were having on the landscape.
Results revealed that the soil in latrine areas contained an average of 62% organic matter, dramatically higher than the mere 1.5% found in deglaciated soil exposed for 85 years without latrines.
“It’s really hard for things to live, but that organic matter made it so that temperatures and moisture levels didn’t fluctuate nearly as much. The latrines created a different microclimate than the surrounding area,” adds Steven Schmidt, a professor from the University of Colorado Boulder.
These bathroom hotspots aren’t just about enriched soil; they’re bustling communities of microscopic life. The concentration of DNA in latrine soils was 37 times higher than in nearby untouched areas, indicating thriving communities of bacteria, fungi, and other microorganisms. Plant coverage was also significantly higher. It was like comparing a patchy lawn (42% coverage in latrine areas) to mostly bare dirt (8.6% in surrounding areas).
The impact extends beyond just plants and microbes. Camera footage has revealed these vegetated patches are attracting diverse wildlife, including rare species never before seen at such high elevations and even large carnivores like pumas. Interestingly, vicuñas themselves return to feed on the vegetation growing in their own latrines.
While this natural process offers hope, scientists caution that it may not be enough to keep pace with rapid glacier loss. Between 2000 and 2019, glaciers (excluding Greenland and Antarctic ice sheets) lost about 267 billion tons of ice annually. If warming continues, Earth could lose 68% of its glaciers, threatening water supplies for nearly a quarter of the world’s population.
“The vicuñas are probably helping some alpine organisms, but we can’t assume they’ll all be okay, because in Earth’s history, we’ve never seen climate change happen at this speed. Current anthropogenic climate change is probably the most severe crisis our planet and all living things have faced in the past 65 million years,” says Bueno de Mesquita.
As global glacier loss accelerates, understanding these natural adaptation mechanisms becomes increasingly crucial. While vicuña latrines alone won’t solve the challenges of climate change, they demonstrate how even the most basic animal behaviors can play a vital role in ecosystem resilience and recovery.
Summary Paper
Methodology
The researchers identified and studied vicuña latrines within glacial moraine soils exposed since the Little Ice Age maximum (around 1850-1900) in the Peruvian Andes, at elevations reaching 18,000 feet above sea level. They selected six focal latrines and paired control sites 5-15 meters away from each latrine. Their comprehensive approach included collecting soil samples, measuring organic matter content and moisture levels, monitoring soil temperatures, and analyzing DNA content and microbial communities. They tracked plant coverage and studied root colonization by various fungi. Additionally, they used camera footage to document wildlife activity around these vegetated patches, revealing unexpected visitors including rare species and large predators like pumas that had never been documented at such high elevations.
Results
The contrast between latrine and control sites was striking. Latrine soils contained 62% organic matter compared to just 1.5% in deglaciated soils exposed for 85 years without latrines. Soil moisture was dramatically higher in latrines (121% vs. 10%), as were DNA concentrations (23.2 vs. 0.62 µg DNA per gram of soil). Plant coverage showed a marked difference, with latrines having 42.3% coverage compared to 8.6% in control sites. The latrines created more stable microclimates, with maximum temperatures averaging 5°C cooler and minimum temperatures about 2°C warmer than control sites. These modified areas attracted diverse wildlife and created nuclei for new ecosystem development.
Limitations
While the study demonstrates the significant impact of vicuña latrines on ecosystem development, several limitations should be noted. The research was conducted in one specific region of Peru, so results might vary in other mountain ranges or with different camelid species. The study couldn’t definitively determine whether the organic matter in latrines came primarily from outside the glacier forefield or from redistribution within it. Most critically, even with these accelerated ecosystem developments, the pace of positive change still lags behind the rate of glacier loss. Between 2000 and 2019, glaciers worldwide lost about 267 billion tons of ice annually, and projections suggest Earth could lose 68% of its glaciers if warming continues at current rates.
Discussion and Takeaways
This research reveals a natural mechanism that could help ecosystems adapt to climate change, albeit not quickly enough to fully counteract its effects. The findings highlight the importance of maintaining healthy wild camelid populations for ecosystem resilience. The study has broader implications for water security, as shrinking glaciers and snow cover could affect water supplies for nearly a quarter of the world’s population. The research also suggests that understanding and protecting animal behaviors – even something as simple as bathroom habits – could be crucial for ecosystem adaptation strategies. However, as the researchers emphasize, while vicuñas are helping some alpine organisms adapt, the unprecedented speed of current climate change presents challenges that far exceed historical patterns of ecosystem adaptation.
Funding and Disclosures
The research was funded by NSF grants DEB-1457827, DEB-1258160, and DBI-2217840. The study involved collaboration between James Madison University, the University of Colorado Boulder, and other institutions. The authors declared no competing interests.
Publication Information
Published in Scientific Reports (2024), Volume 14, Article number 31913, titled “Wild Andean camelids promote rapid ecosystem development after glacier retreat” by Kelsey E. Reider, Clifton P. Bueno de Mesquita, et al. The study was released on December 30, 2023, and contributes to our understanding of how natural mechanisms might help ecosystems adapt to climate change.
