- The vicuña, a wild relative of the llama, could help reestablish plants in barren areas where glaciers have melted, according to a recent study in the high Andes of Peru.
- As vicuñas tend to poop in the same places, they establish communal latrines where soils have much higher moisture, organic matter, nutrients and microorganisms than surrounding areas formerly covered by ice.
- Researchers say they believe these more nutrient-rich soil patches can speed up plant colonization by as much as a century and provide refuge for plant species moving uphill as temperatures increase.
- Peru is losing its glaciers at a worrying speed, with research pointing out that in the Central Andes, between 84% and 98% of their glaciers might disappear by 2050.
The vicuña’s social habit of pooping in the same place could help Andean ecosystems adapt as glaciers rapidly retreat due to climate change. Researchers found that communal loos for vicuñas (Lama vicugna), a wild camelid relative of the llama, in barren and recently deglaciated areas in the high Andes in southeastern Peru are packed full of nutrients that encourage plant growth.
These latrines act as little islands of nutrients and biodiversity as a recently deglaciated landscape is mostly gravel and rock, barely constituting soil, says Clifton Bueno de Mesquita, a research scientist in the Department of Ecology and Evolutionary Biology at the University of Colorado Boulder, co-author of the study published in Nature Scientific Reports.
“That’s why the vicuña poop has such a large impact,” Bueno de Mesquita says. “They’re helping plants establish in these harsh environments much faster than they would otherwise.”
After sampling soils in the latrines and comparing them with nearby deglaciated areas, the researchers found that latrines have far higher levels of moisture and key nutrients, such as nitrogen and phosphorus, and were teeming with microorganisms. Soil in the latrines also had 62% organic matter, while deglaciated soils had as little as 1.5%. All in all, these conditions enable microbes and plants to thrive, according to the study, which focused on the Sibinacocha watershed in the Cordillera Vilcanota, in the department of Cusco, which is experiencing rapid glacier melting.
The pace of glacier loss in the region is staggering. A paper published in 2024 found that the Peruvian Central Andes could lose between 84% and 98% of their glaciers by the 2050s. In the case of the area covered by the Scientific Reports study, the nearby glacier has retreated by around 18 meters (59 feet) per year over the past two decades, says Kelsey Reider, a study co-author and an ecologist at James Madison University.
The study authors say the vicuña’s communal pooping practice could speed up the colonization process, or plant succession, in deglaciated areas by as much as a century. That could provide vital refuge for plant species retreating uphill in the face of climate change. They also found that a host of other wildlife, including pumas, visit these latrines.
“[This] paper provides compelling evidence that wild Andean camelids function as ecosystem engineers in proglacial landscapes, accelerating soil development and primary succession,” Anaïs Zimmer, a researcher at the Research Institute for Development who was not involved in the study, told Mongabay in an email. But she also notes the study is limited to one location and one group of animals.
“Future research should explore whether similar mechanisms occur in other glacial forefields across the Andes and assess the potential influence of domesticated camelids (e.g., llamas and alpacas) on ecosystem succession,” she says.
Keeping up with climate change
By creating these islands of biodiversity, vicuñas could help other alpine species adapt to new environments. The researchers found that as well as speeding up the colonization process of deglaciated areas by up to a century, the latrines form their own microclimate. This can help plant species buffer against the wide daily temperature variations that occur at such high altitudes.
That means they may become a refuge for some alpine plant species moving upland as lower altitude levels become less suitable due to increasing temperatures, Bueno de Mesquita says.
The pace of glacier loss makes it highly unlikely that vicuña poop alone can keep up with this rapidly changing environment, yet it does point to the importance of their conservation. Vicuñas were once on the brink of extinction across their range due to rampant poaching, but an international recovery effort restored populations.
“I don’t think we expect vicuñas to go and poop on the entire landscape,” Reider says. But given the research results, she says it is clear that the presence of this species is hugely important for ecosystem growth in previously glaciated areas. “I think that if the vicuñas had not been recovered, we would not have this as a potential nature-based, native species type of influence on the trajectory of primary succession in the high Andes.”
Based on the recent paper, protecting and reintroducing vicuñas to other areas of their former range could potentially aid climate adaptation and support local economies and livelihoods, Zimmer says, but that would have to include an assessment of any negative impacts.
Julia Monk, assistant professor in the Department of Environmental Studies at New York University, agrees the study does offer evidence of an important ecosystem service provided by vicuñas’ social behavior. But she is hesitant when it comes to stating that all reintroduced species or populations will guarantee plant colonization in deglaciated areas.
“You might need to build up many different missing pieces [in the ecosystem], not just this one species, but other interacting species to see sort of the same cascade of processes happen,” Monk, who was not involved in the research, tells Mongabay.
She also raises the concern that some vicuña populations face the threat of sarcoptic mange outbreaks. The highly infectious skin disease has already wiped out populations in Argentina where she works and is a pressing conservation challenge. “If the vicuña populations were to be totally lost, you could expect to see major changes to vegetation and soil conditions that would likely have many other sort of rippling effects throughout the ecosystem,” she says.
Delving deeper
The paper raises plenty of other questions with implications for climate adaptation. For now, the researchers aren’t entirely sure why vicuñas venture into the deglaciated areas in the first place. They do eat the vegetation that grows in their own latrines, but what drives them there before their formation isn’t certain. It could be part of a daily antipredator migration or for other currently unknown reasons, Reider says.
She explains that the study group is exploring numerous research topics, including whether vicuñas are also dispersing seeds as well as nutrients in these areas. Past research by Zimmer and her team showed that the vicuña’s close relative, the llama, does disperse seeds in latrines, indicating this may be the case, but it is still under investigation.
Researchers also plan to use drones and potentially satellite imagery to understand how the individual latrines grow over time and may eventually create larger patches or even meadows. “One of the unknowns here is how do those small, nutrient-rich patches and the plant and animal communities that become established or utilize those patches influence the broader ecosystem on a landscape scale?” Reider says.
“I think there’s going to be a lot of value in continuing to monitor these patches and see how they might expand, how they might connect, and how you go from a patch or multiple patches to an entire meadow,” Bueno de Mesquita says, adding that with climate change rapidly changing the landscapes of the high Andes, understanding its implications is vital. “These issues and these ecosystems are really important for biodiversity as well as humans, so they’re worth studying.”
Citations:
Reider, K. E., Bueno de Mesquita, C. P., Anderson, K., Pilco, R. Q., Luza Victorio, M. A., Gelona, A. R., & Schmidt, S. K. (2024). Wild Andean camelids promote rapid ecosystem development after glacier retreat. Scientific Reports, 14(1). doi:10.1038/s41598-024-83457-6
Arias, A., Núñez, N., Rau, P., & Venail, P. (2024). Development of a spatial projection map of glacial retreat based on vulnerability maps in the central cordillera, Peru. Journal of Water and Climate Change, 15(6), 2863-2884. doi:10.2166/wcc.2024.151
Acebes, P., Vargas, S., & Castillo, H. (2022). Sarcoptic mange outbreaks in vicunas (Cetartiodactyla: Camelidae): A scoping review and future prospects. Transboundary and Emerging Diseases, 69(5). doi:10.1111/tbed.14479
Zimmer, A., Beach, T., Riva Regalado, S., Salcedo Aliaga, J., Cruz Encarnación, R., & Anthelme, F. (2023). Llamas (Llama glama) enhance proglacial ecosystem development in cordillera Blanca, Peru. Scientific Reports, 13(1). doi:10.1038/s41598-023-41458-x
Banner image: A recent study shows that social behavior of the vicuña, a relative of the llama, can aid ecosystem adaptation as glaciers retreat due to climate change. Image courtesy of Lee Fitzgerald/ Texas A&M University.
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