Predators form an unusual coexistence in the central Chilean Andes

In the high plains of the central Chilean Andes, an ecosystem made up of just a few animal species is providing researchers with new insight into how predators coexist in nature.

“The puma and the culpeo fox are the only major predators in the Chilean Andes landscape,” said Professor Marcella Kelly, College of Natural Resources and Environment. “And there isn’t a wide range of prey species, in part because guanacos [closely related to llamas] are generally no longer found in these areas due to overhunting. With such a simplified ecosystem, we thought we could really figure out how two rival predators interact. “

Kelly worked with Christian Osorio, a doctoral student in the Department of Fish and Wildlife Conservation, and researchers from the Pontifical Catholic University of Chile to map the locations and potential interactions between pumas and foxes in the center of the Chile. They focused on three axes of interaction: spatial (where animals are in the landscape), temporal (the moment of specific activities on a given landscape) and diet (what each species eats).

To understand the interaction between pumas and foxes, the researchers deployed 50 camera stations at two sites in central Chile, one in the Rio Los Cipreses National Reserve and the other on private land where cattle and the horses are bred. They also collected excrement samples from both locations to analyze the feeding of the pumas and foxes.

The team’s findings, published in the journal The diversity, showed that while pumas and foxes overlapped significantly where they lived and what time they were active, there was little overlap in what they ate, with pumas’ diets mainly consisting of a large species of hare introduced to Europe, while culpeo foxes preferred smaller rabbits, rodents and seeds. The two predator species can successfully share a landscape and hunt for food during the same hours of the night, as they essentially order from different menus.

“It is likely that the foxes realized that when they try to hunt hares, they might have problems with the pumas,” Osorio explained. “If they hunt smaller mammals, pumas don’t care, but if foxes start targeting larger prey, pumas will react.”

How predator species interact is a crucial question for environmentalists trying to understand the dynamics that inform ecosystem balances. And while the cougar has been designated as the species of least concern, animal populations are in decline and continue to be watched by conservationists.

“Less worry doesn’t mean no worry,” Osorio noted. “We have laws in Chile that protect the species, but the data we have to make a conservation designation is very scattered. As we accumulate more consistent and reliable data, the puma may be reclassified as vulnerable or even endangered.

Hares, which make up about 70 percent of the biomass in the cougar’s diet, are a non-native species, introduced to the region by European settlers. The guanacos being absent from the landscape, the puma had to adapt its diet to survive.

With some land managers and conservationists campaigning for the removal of introduced hare species in order to restore the region’s native ecosystem, Kelly and Osorio note that it is important to understand that pumas would be significantly affected by a reduction in their size. main source of food.

Another concern, which the two are currently investigating, is the interaction between wildlife and humans. The national reserve is seeing more and more visitors keen to observe big cats and foxes in their natural environment, while the sheep and cattle industries increasingly use remote land for breeding.

“Cougars occasionally kill livestock, which is a challenge we’re looking at right now,” said Kelly, an affiliate of the Fralin Life Sciences Institute at Virginia Tech. “The government would like to preserve the puma, but there are competing challenges as to the type of threat it poses to livestock and the type of threat that cattle or sheep farming poses to them.

Understanding how two predatory species can coexist has the potential to provide conservationists and conservationists with better ideas about how humans and wildlife can share a landscape.