On the Patagonian coast of Argentina, an unexpected wildlife conflict is taking place. Pumas are increasingly hunting Magellanic penguins, one of the region’s most recognizable animals. Pumas are large wild cats that have recently returned to an area where they once lived. A new scientific study has looked at whether this growing interaction could threaten the long-term survival of the penguin population.
The research was published in the Journal for Nature Conservation. It was carried out by scientists from Argentina together with researchers from the University of Oxford. The study focuses on Monte León National Park, a protected coastal region where both penguins and pumas now live side by side. Pumas once lived widely across southern Argentina. However, their numbers fell sharply during decades of cattle ranching. Predators were frequently killed to save livestock in those days. In the 1990s, many ranches in this region were abandoned. The closure allowed pumas to slowly return to their former habitat.
At the same time, Magellanic penguins moved their nesting colonies from offshore islands to the mainland. These mainland sites had been safe in the past because there were no large land predators. That situation changed when pumas returned to the area. Penguins have no natural defense against large carnivores, which makes them easy prey. Rangers and scientists working in Monte León National Park began finding large numbers of dead penguins. Many carcasses showed clear signs of puma attacks.
Researchers studied the penguin colony for four years, from 2007 to 2010, to understand the problem. During this time, they recorded thousands of adult penguins killed by pumas. Their results suggested that over four years, more than 7,000 adult penguins were killed. This was about 7.6% of the adult population, which numbered around 93,000 birds. What worried scientists most was that many penguins were not completely eaten. The results showed that pumas were killing more penguins than they needed for food. This behavior is called “surplus killing.” It usually happens when prey is simple to catch and plentiful. It is similar to how domestic cats sometimes hunt birds even when they are not hungry.
Despite the large number of deaths, the study found that puma predation alone is unlikely to destroy the penguin colony. Using population models, researchers showed that the colony’s survival depends much more on breeding success and on how many young penguins survive to adulthood. The models showed that the penguin population would only face extinction under extreme conditions.
These include very low chick production combined with poor survival of juvenile penguins. High levels of puma predation could make the situation worse, but they are not the main factor driving population decline.
This shifts attention to other major threats to penguins. These include food availability, ocean temperatures, and nutrient levels in the sea. Climate change strongly affects all these factors. They play a key role in penguin reproduction and chick survival. The researchers say their finding highlights a growing conservation challenge. It raises an important question: how should humans respond when a recovering predator threatens another vulnerable species? Human actions have impacted both protected animals, penguins and pumas, in the past.
Similar situations are occurring in other parts of the world. In the United States, feral pigs are destroying sea turtle nests along the Georgia coast. Coyotes are also moving onto coastal islands, where they are affecting bird populations.
Long-term monitoring is crucial, the authors say. It helps scientists spot population declines early and make better conservation choices. At Monte León National Park, authorities continue to closely watch both pumas and penguins. Their goal is to protect the balance of this recovering ecosystem.
As wild predators reclaim their former territories, new and unexpected interactions are becoming part of the natural environment. This reminds us that conservation is rarely simple. Effective solutions must consider entire ecosystems, not just individual species.
